Wednesday, November 15, 2017

CANCER AT SELECTED SITES IN THE BODY

cancer effects on the body
A second and more familiar way to describe cancer is on the basis of the organ site at which it occurs.  A lack of space, in combination with the wide array of human cancers, limits the number of specific malignancies that can be described.  Remember, also, that regular screening procedures can lead to early identification of cancer at these sites.
Lung cancer
Lung cancer is one of the most lethal and frequently diagnosed forms of cancer.  Primarily because of the advanced stage of the stage of the disease at the time symptoms first appear, only 15% of all people with lung cancer (all stages) survive 5 years beyond diagnosis.  By the time a person is sufficiently concerned about having a persistent cough, blood-streaked sputum, and chest pain, it is often too late for treatment to be effective.  This failure to be able to diagnose lung cancer in its earlier stages could, however, begin to change.  Currently the National Cancer Institute is studying the efficacy of spiral CT scans in  detecting lung tumors earlier than can be done by conventional chest x-rays.  However, an initial assessment of the technology questions its cost-effectiveness and potential for excessive false-positive findings.
Risk Factors
Today it is known that a genetic predisposition is important in the development of lung cancer.  Perhaps, in fact, the majority of people who develop this form of cancer have an inherited “head start.”  When people who are genetically at risk also have smoke, their level of risk for developing lung cancer is significantly greater than it is for nonsmokers.  Of particular interest at this time are multiple genes on chromosome 3.  Damage to three tumor suppressors on this chromosome is found in virtually every case of small-cell lung cancer and 90% of nonsmall-cell lung cancer.  Most of the remaining lung cancer cases appear in people who smoke but are not genetically predisposed.
Cigarette smoking is unquestionably the single most important behavioral factor in the development of lung cancer.  For men who smoke, the rate of lung cancer is twenty-three times higher than for men who do not smoke.  For women who smoke, the rate is eleven times higher than for women who do not smoke.  Smokers account for the vast majority of all reported cases of lung cancer, and lung cancer itself produces at least 30% of all cancer-caused deaths.
Since 1987, lung cancer has exceeded breast cancer as the leading cause of cancer deaths in women.  This incidence of lung cancer has shown an encouraging decline in men that parallels their declining use of tobacco products, although it remains the leading cause of cancer deaths in men as well.  Environmental agents, such as radon, asbestos, and air polluntants, make a smaller contribution to the development of lung cancer.  Radon along may be the principle causative agent in most lung cancer found in nonsmokers.
Prevention
The preceding information clearly suggests that not smoking or quitting smoking and avoidance of environmental tobacco smoke are the most important factors in the prevention lung cancer.  In addition, place of residence, particularly as it relates to air pollution, is a long-suspected risk factor for lung cancer.  Nonsmokers who are considering living with a smoker or working in a confined area where environmental tobacco smoke is prevalent should carefully consider the risk of developing lung cancer.  A recent study does, however, lessen concern over moderate alcohol use and the risk of developing lung cancer.
Treatment
The prognosis for surviving lung cancer remains extremely guarded.  Depending on the type of lung cancer, its extent, and factors related to the patient’s overall health, various combinations of surgery, radiation, and chemotherapy remain the physicians’ primary approach to treatment.  Today, for persons with early stage lung cancer, chemotherapy, following surgery, has increased survivability slightly.  Additionally, new medications that primarily shrink tumors are also available.  Although these newer therapies have improved short-term survival, full recovery remains unlikely in all but a small percentage of cases.
Breast Cancer
Surpassed only by lung cancer, breast cancer is the second leading cause of death from cancer I women.  It is the third leading cause of cancer deaths overall.  Nearly one in eight women will develop breast cancer in her lifetime, resulting in an estimated 211,300 new invasive cases and 40,200 deaths in 2003.  In men, an estimated 1,300 new cases and 400 deaths occurred in 2003.  As they age, women’s risk of developing breast cancer increases.  Early detection is the key to complete recovery.  Ninety-seven percent of women who discover their breast cancer before it has spread (metastasized) will survive more than 5 years.
Risk Factors
Although all men and women are at some risk of developing breast cancer, the following groups of women have a higher risk.
·         Women whose menstrual periods began at an early age, or whose menopause occurred late (although the former may be more powerful than the latter)
·         Women who had no children, had their first child later in life, or did not nurse.
·         Women who have used hormone replacement therapy
·         Women whose diets are high in saturated fats, those who are sedentary, and those with excessive central body cavity fat
·         Women with a family history of breast cancer
As presented in the bulleted list, significant concerns exist regarding the long-term use of hormone replacement therapy and the development of breast cancer in post-menopausal women.  In fact, in a government-sponsored study (Women’s Health Initiative Study) the link appeared so strongly and early that the study was terminated much earlier than had been planned.  Researchers found that tumor development in women taking HRT versus those on a placebo was more common, that tumors were larger at diagnosis, and that tumors were more often invasive.  Physicians are now advising that HRT be used only on a very short-term basis to relieve the symptoms of menopause, rather than the much longer period of time previously deemed appropriate.
The effects of environmental pollutants and regional influences have also been investigated as causative factors in the development of breast cancer.  Environmental pollutants vary from region to region and a influenced by a number of factors, including the type of industrial and agricultural activity in a particular area.  A wide array of regional factors may be involved, including genetic background of people in a given area and lifestyle differences involving diet, alcohol consumption, and exercise patterns.
The role of genetic predisposition in the development of breast cancer has also received considerable attention.  For example, a small percentage (perhaps 5%) of women with breast cancer have inherited or developed mutations on one or both of two tumor suppressor genes (proto-oncogenes), BRCA1 and BRCA2.  Discovered in 1994 and 1995, respectively, and currently the focus of extensive research, more than two hundred mutations in these genes have been identified.  In a recent study involving 5,000 Ashkenazi Jews (Jews of Central and Eastern European descent) living in the Washington, D.C., area, mutation in the BRCA1 gene resulted in a 56% greater chance of developing breast cancer by age 70 (versus a 13% greater risk for people without a mutated version of the gene).  A more recent study suggests a role not only for mutations to BRCA1 but not genetic material nearby on the same chromosome.  A mutation in the BRCA2 gene has been found to be less likely to foster the development of breast cancer than the BRCA1 mutation.  Both of these genes are also associated with increased risk of developing ovarian cancer and, perhaps, prostate cancer in men.
Other genetic links to breast cancer have been identified.  For example, one involves an increased risk for breast cancer development in black women.  The gene in question is BPI, a gene that, if shut off, allows cancer cells to establish cellular immortality.  Factors that influence this gene to become dysfunctional have not been identified.
Prevention
As already discussed, a variety of risk factors are thought to be important in the development of most cases of breast cancer.  Accordingly, some degree of prevention is possible when factors such as diet; alcohol use; physical activity level; decision about contraception, pregnancy, and breastfeeding; occupational exposure to toxins; and even place of residence are considered.
For women who have a primary family history of breast cancer (sisters, mothers or grandmothers with the disease) and who have been found to carry one or both of the mutated suppressor genes discussed, an extreme form of prevention is also possible – prophylactic mastectomy.  In this surgical procedure, both noncancerous breasts are removed, in an attempt to eliminate the possibility of future cancer development.  When carefully planned, breast reconstruction surgery can be undertaken immediately, with satisfactory results.  A high level of satisfaction was found among women who had undergone this procedure.
At the present time pharmacological prevention represents the newest approach to reducing the incidence of breast cancer.  Two medications, Evista, or raloxifene (a drug developed for use in osteoporosis prevention), and tamoxifen (an estrogen-receptor blocker developed for use in the treatment of cancer) have been found to be effective in lowering the risk of cancer in high-risk women.  However, a warning (August 2000) from the FDA reminds physicians that tamoxifen can have serious side effects, including the development of uterine cancer and potentially fatal blood clots.
Early Detection: Breast Self-Examination
For several decade a fundamental component of early detection of breast cancer has been breast self-examination (BSE).  Generally recommended for women 20 years of age and older, the procedure was to be performed during the menstrual period or during the day immediately following the end of the menstrual period, when estrogen levels are at their lowest and cystic activity in breast tissue in minimal (or on the same day of each month by postmenopausal women).  Although breast self-examination is an easily learned technique, today its value is being strongly challenged by researchers in both this country and in China.  It has, in fact, become the contention of some that teaching BSE to another generation of women is a misuse of time and money that could be better spent on other screening techniques.  Others, however, feel that women who know the technique should not be discouraged from using BSE, but they also should not be regularly reminded of its significant limitations in finding tumors.  In 2003, the American Cancer Society revised its recommendation for breast cancer screening to better address the doubts regarding BSE’s limitations.  Specific to BSE the following statement summarizes the ACS’s current position.
Previously, the guidelines (BSE) recommended women perform breast self-exam every month.  Now, (we) recommend that, beginning in their 20s, women should be told about the benefits and limitations of BSE, and that it is acceptable for women to choose not to do BSE, or to do it occasionally.  The importance of promptly reporting changes to a physician is emphasized.
The reason for this change is that research has shown that BSE plays a very small role in detecting breast cancer compared with self-awareness.
Regardless, monthly BSE can be viewed as an adjunct to regularly scheduled breast examination conducted by a physician and to the routine use of mammography.
Early Detection: Mammography
Although researchers once disagreed about the age at which women should begin routine mammography and the extent to which mammography is effective in finding masses in dense breast tissue, today mammograms are physicians’ best tool for early detection of breast cancer.  Accordingly, the American Cancer Society recommends that mammography begin at age 40.
Whether women begin routine mammography at 40, as advised by the ACS, or as early as 35 years of age, particularly for women with earlier symptoms or a family history of breast disease, women should continue these examinations on an annual basis.  Recommendations regarding mammography for older women (65+) are, however, a bit more individually determined and should be discussed annually status and expectations for reaching a normal life expectancy will be weighed relative to the lowering cost-effectiveness of mammography.
Because of the important role routine mammography plays in the early identification of breast lesions, the Mammography Quality Standards Act (MQSA), formulated by the FDA (April 1998), is a valuable step toward ensuring that mammography is performed by experienced technicians, using correctly calibrated equipment, and interpreted by skilled radiologists.  Every woman should be certain that her mammography is being performed in a MQSA-certified facility.
Treatment
Regardless of the method of detection, if a lump is found, a breast biopsy can determine whether the lump is cancerous.  If the lump is cancerous but localized, treatment is highly effective, with cure rates at nearly 100 percent.  The most frequently used treatments are lumpectomy combined with radiation, lumpectomy without radiation, and mastectomy.  The use of chemotherapy following surgery is strongly advocated as well.
When drug therapy is deemed desirable in treating breast cancer, oncologists may consider two drugs that have been redefined.  The first, tamoxifen, discussed earlier in terms of breast cancer prevention, is a hormonelike drug that prevents estrogen from stimulating cancer cell growth.  The use of tamoxifen has proven highly effective in women who have the type of breast cancer stimulated by the presence of estrogen.
The second drug, Herceptin, is an antibodylike agent used in combination with other chemotherapeutic drugs in highly advanced breast cancer.  This newly approved drug interferes with the activity of a protein produced by the HER-2 oncogene that normally fosters tumor cell division.
Cervical Cancer
 In 2003 an estimated 12,200 new cases of cancer of the cervix (the anatomical neck of the uterus) occurred in the United States.  Fortunately, the death rate from cervical cancer has dropped greatly since 1950, largely because of the Pap test.  This test screens for precancerous cellular changes (called cervical intraepithelial neoplasia, or CIN) and malignant cells.  If malignant cells are found, it is hoped that they represent only cancer in situ (at the site of origin), rather than a more advanced invasive stage of the disease.  Unfortunately, this simple and relatively inexpensive screening test is still underused, particularly in women over age 60, the group in which cervical cancer is most frequently found.
Risk Factors
Because of the clear association between sexually transmitted infections and cervical cancer, risk factors for this form of cancer include early age of first intercourse, large number of sexual partners, history of infertility (which may indicate chronic pelvic inflammatory disease), and clinical evidence of human papillomavirus infections.  For patients with previous HPV infections or whose sexual history suggests a higher risk of HPV, a ThinPrep Pap test has been effective in detecting the DNA from four HPVs that are known to be cancer causing, while being as easy to use as the more widely used Pap smear.  Today the test is only approved for identifying HPV infection, but it is also capable of detecting both chlamydia and gonorrhea.  At the time of writing, human trials (stage 1) are underway on a vaccine designed to protect against some HPV infections.  Initial human studies have been highly effective in preventing effections from the most virulent of the HPVs, type 16.  Cigarette smoking and socioeconomic factors are also risk factors for cervical cancer.  The latter most likely relates to less frequent medical assessment, including infrequent Pap tests.
Prevention
Sexual abstinence would be the most effective way of reducing the risk of developing cervical cancer (fro example, Catholic nuns have extremely low rates of cervical cancer).  However, since this is unlikely to be the choice for most women, other alternatives include fewer sexual partners, more careful selection of partners to minimize those at high risk, the use of condoms, and the use of spermicides.  In addition, of course, regular medical assessment, including annual Pap tests (and the ThinPrep Pap test), represents prevention through early detection.  Of course, when widely available, the HPV vaccine will further increase prevention.
Early Detection
At this time, the importance of women having Pap tests for cervical cancer performed on a regular basis cannot be overemphasized.  However, the specific scheduling of cervical screening is undergoing adjustment.  For young sexually active women, initial screening using the Pap smear (preferably in combination with the ThinPrep) should be undertaken within 3 years of first exposure.  For young women not sexually at risk, oe for women who have had a hysterectomy, the initial screening with the Pap smear can be determined in consultation with health care providers.  Once initiated, however, following three consecutive annual negative tests, the interval between tests may be increased upon discussion with health care providers.  The American Cancer Society estimates that cervical cancer claimed the lives of 4,100 women in 2002.
The Pap test is not perfect, however.  When tests are read in laboratories highly experienced in interpreting Pap slides, about 7% will be false negatives, resulting in a 93% accuracy rate.  In less-experienced laboratories, false negatives may be as high as 20%.  In addition, not all women whose test results are accurately assessed as abnormal receive adequate follow-up care, nor do they have subsequent Pap tests regularly enough.
In addition to changes discovered by a Pap test, symptoms that suggest potential cervical cancer include abnormal vaginal bleeding between periods and frequent spotting.

Treatment
Should precancerous cellular changes (CIN) be identified, treatment can include one of several alternatives.  Physicians can destroy areas of abnormal cellular change using cryotherapy (freezing), electrocoagulation, laser destruction, or surgical removal of abnormal tissue.  More advanced (invasive) cancer of the cervix can be treated with a hysterectomy combined with other established cancer therapies.  A combination of radiation and chemotherapy is the most effective treatment for cervical cancer.
Uterine (Endometrial) Cancer
The American Cancer Society estimates that in 2003, 40,100 cases of uterine cancer (cancer within the inner wall of the body of the uterus, rather than within the cervix or neck of the uterus) were diagnosed in American women.  In addition, 6,600 women died of the disease.  Although African Americans have a lower incidence of uterine cancer than white women, their death rate is nearly twice as high.
Risk Factors
Unlike cervical cancer, in which a strong viral link has been identified, the principle risk factor related to the development of endometrial cancer is a high estrogen level.  Accordingly, the following factors are related to higher levels of estrogen and, thus, to the development of endometrial cancer:
·         Early menarche (early onset of menstruation)
·         Late menopause
·         Lack of ovulation
·         Never having given birth
·         Estrogen replacement therapy (ERT not moderated with progesterone)
·         Use of tamoxifen (a drug used in breast cancer therapy)
To some degree, endometrial cancer is seen more frequently in people who are diabetic, obese, or hypertensive or who have gallbladder disease, or a family history of colon cancer.
Prevention
The risk factors associated with high levels of estrogen are areas in which prevention might be targeted.  In addition, the need regular gynecological care that includes pelvic examination is a principle factor in minimizing the risk of uterine cancer.  Pregnancy and the use of oral contraceptives both provide some protection from endometrial cancer.
Early Detection
Compared with cervical cancer, which is routinely identified through Pap tests, endometrial cancer is much more likely to be suspected on the basis of symptoms (irregular or postmenopausal bleeding) and confirmed by biopsy.  Although more invasive, biopsy is a more effective method than ultrasound to diagnose uterine cancer.
Treatment
The treatment for early or localized endometrial cancer is generally surgical removal of uterus (hysterectomy).  Other therapies, such as radiation, chemotherapy, and hormonal therapy, may then be added to the treatment regimen.  However, in terms of hormone replacement therapy (HRT), in which estrogen is combined with a synthetic progesterone, the FDA, The National Institute on Aging, and various medical associations now advise that no women 65 or older should take HRT due to several concerns, including an increased risk for endometrial cancer.  For women who are undergoing menopause and experiencing troublesome symptoms such as night sweats and hot flashes, HRT should be used in the smallest doses that provide relief and for the shortest duration of time possible.
Ovarian Cancer
Since the death in 1989 of actress Gilda Radner, a star in the early years of Saturday Night Live, public awareness of ovarian cancer has increased in the United States.  The American Cancer Society estimates that in 2003, there were 25,400 new cases diagnosed and 14,300 women died of the disease.  Most cases develop in women over age 40 who have not had children or began menstruation at an early age.  The highest rate is in women over age 60.  Today ovarian cancer causes more deaths than any other form of female reproductive system cancer.
For relatedly small percentage of all women (10%), the inheritance of either the BRCA1 or BRCA2 suppressor gene mutation significantly increases the risk of developing both breast and ovarian cancer.  Today it is estimated that about 20% of all cases of ovarian cancer stem from these genetic mutations.
Beyond the 20% of cases attributed to genetic mutations, what might account for the majority of ovarian cancers? Today accumulated evidence points to the several decades during which millions of menopausal and post-menopausal women were placed on estrogen replacement therapy (ERT), often for years to counter the symptoms of menopause, maintain bone mass, and continue hormonal protection from cardiovascular disease.  As mentioned in conjuction with endometrial cancer, today hormone replacement therapy (HRT) is used, and then for only the briefest period of time.
Prevention
Methods of preventing or lowering the risk of developing ovarian cancer are very similar to those recommended for breast cancer.  These include using oral contraceptives, giving birth and breastfeeding (for at least three months), reducing dietary fat intake, abstaining from alcohol use, and performing regular physical activity.
For the small group of women with a strong family history of ovarian cancer, a prophylactic oophorectomy should be seriously considered.  In this surgical procedure, both ovaries are removed.  Carefully monitored hormone replacement therapy is then used to provide the protective advantages of estrogen in maintaining cardiovascular health and bone density.
Early Detection
Because of its vague symptoms, ovarian cancer has been referred to as a silent cancer.  Women in whom ovarian cancer has been diagnosed often report that the only symptoms of their cancer’s presence were digestive disturbances, gas, and stomach distention.  For this reason, annual pelvic examinations are important.
For women with a strong family history of ovarian cancer (four primary family members who have had breast or ovarian cancer, with two or more cases occurring before age 50) or women of Ashkenazi Jewish descent, genetic screening and transvaginal ultrasound screening are likely to be recommended.  These women may also be referred for participation in one of several prevention trials now under way.
Treatment
At this time, treatment of ovarian cancer requires surgical removal of the ovary, followed by aggressive use of chemotherapy.  Use of the chemotherapeutic drug Taxol, obtained from the bark and needles of the Pacific yew tree, results in a 50% survival rate 19 months after the completion of therapy.  Most recently, use of an experimental three-drug combination has resulted in a 70% survival rate 22 months after chemotherapy.
Prostate Cancer
If the names Bob Dole, General Norman Schwarzkopf, Colin Powell, and Rudy Giuliani are familiar, then you know four older men who have been diagnosed with and treated for prostate cancer.  In fact, prostate cancer is so common that in 2003 an estimated 220,900 new cases were diagnosed and 28,900 men died of the disease.  Prostate cancer is the second leading cause of cancer deaths in Americans men, exceeded only by lung cancer deaths.  Cancer of the prostate is the third most common form of cancer in men and a leading cause of death from cancer in older men.
The prostate gland is a walnut-size gland located near the base of the penis.  It surrounds the neck of the bladder and the urethra.  The prostate secretes a number of components of semen, such as nutrients used to fuel sperm motility.
Risk Factors
Compared with other cancers, the risk factors for prostate cancer are less clearly defined.  The most predictable risk factor is age.  Nearly 80% of all prostate cancer cases are diagnosed in men over 65 years of age, while cases in men and men with a family history of prostate cancer are at greater risk of developing this form of cancer.  A link between prostate cancer and dietary fat intake, including excessive red meat and dairy product consumption, has also been suggested.  With the discovery of the BRCA1 and BRCA2 genes related to breast and ovarian cancer, a genetic link with prostate cancer was also established.  Men with one of these genetic mutations have an increases risk of developing prostate cancer.
 Prevention
Although the American Cancer Society does not specifically address prevention of prostate cancer, prevention is not an unrealistic goal.  Clearly, moderation of dietary fat intake is a preventive step.  Increased dietary intake levels of vitamin E and the micronutrient selenium have been shown to play a preventive role in prostate cancer.  In addition, effective treatment of benign prostatic hyperplasia (BPH) (prostate enlargement) with the drug Proscar (finasteride) has proven effective in preventing low-grade tumors in clinical trials.
Early Detection
A physician should be consulted if any of these symptoms appear, particularly in men aged 50 or older.  Screening for prostate cancer should begin by age 40.  This screening consists of an annual rectal examination performed by a physician and a blood test, the prostate-specific antigen (PSA) test, administered every 2 years.  Another version of the PSA test has also been developed.  This test can identify the “free” antigen most closely associated with the more aggressive forms of prostate cancer, thus cutting down on the false positives and extensive use of biopsies.  In addition, an ultrasound rectal examination is used in men whose PSA scores are abnormally high.  In spite of the important contribution made by the PSA test, there is some concern about the possibility of overtreating 30 of men in the 60 to 84 age group, particularly in light of the side effects of treatment described below.
Treatment
Today prostate cancer is treated surgically, or through the use of external radiation or the implantation of radioactive seeds (brachytherapy) into the gland.  Of course, each form of treatment carries the potential for side effects, including an 80% chance of impotence over a 10-year period; incontinence with surgery; diarrhea and tiredness with external radiation; and some anal discomfort in association with the implantation of radioactive seeds into the prostate with internal radiation.  The latter form of radiation therapy is highly effective for early-stage disease.  One form of prostate cancer grows so slowly that men whose cancer is of this type, whose tumors are very localized, and whose life expectancy is less than 10 years at the time of diagnosis will not receive treatment but rather will be closely monitored for any progression of the cancer.  For men who have the more aggressive form of the cancer, or whose tumor is no longer localized, physicians can employ a range of therapies, including surgery, radiation, chemotherapy, and hormonal therapy.  In addition, an experimental vaccine has recently been tested on humans.
Testicular Cancer
Cancer of the testicle is among the least common forms of cancer; however, it is the most common solid tumor in men ages 15 to 34.  Awareness of this type of cancer was raised in 1996 and 1997, when five-time winner of the tour de France Lance Armstrong and champion figure skater Scott Hamilton were diagnosed with testicular cancer.  In both men, chronic fatigue and abdominal discomfort were the first symptoms of the disease.  The American Cancer Society estimates that in 2003 testicular cancer was diagnosed in 7,600 men and caused the deaths of 400.
Risk Factors
Risk factors for testicular cancer are variable, ranging from family history to environmental factors.  The disease is more frequently seen in African Americans and in men whose testicles were undescended during childhood.  Additional risk factors, such as difficulty during the mother’s pregnancy, elevated temperature in the groin, and mumps during childhood, have been reported.  The incidence of this cancer has been increasing in recent decades, while a corresponding drop in sperm levels has also been observed.  Although no single explanation can be given for these changes, environmental factors such as agricultural pesticide toxicity may be involved.  Once pesticides are concentrated in the tissues of the human body, during pregnancy they mimic estrogen.  This, in turn, leads to testicular dysgenesis syndrome, or the failure of the testicles to develop normally.
Testicular cancer is more frequently seen among white-collar workers than among people in blue-collar occupations.  The suspicion that testicular cancer is linked to vasectomies appears to be unfounded.
Prevention
Because risk factors for testicular cancer are so variable, prevention is limited to regular self-examination of the testicles.  Symptoms such as fatigue, abdominal discomfort, and enlargement of the testicle should be reported to a physician, since this can be associated with other disease processes.  A male infant with one or both testicles in the undescended position (resulting in an empty scrotum) should be seen promptly by a physician so that corrective procedures can be undertaken.
Early Detection
In addition to the fatigue and abdominal distress reported by both Armstrong and Hamilton, other symptoms of testicular cancer include a small,  painless lump on the side or near the front of the testicle, a swollen or enlarged testicle, and a heaviness or dragging sensation in the groin or scrotum.  The importance of testicular self-examination, as well as early diagnosis and prompt treatment, cannot be overemphasized for men in the at-risk age group of 15 to 34 years.
Treatment
Depending on the type, stage, and degree of localization of the tumor, surgical intervention generally includes removal of the testicle, spermatic cord, and regional lymph nodes.  Chemotherapy and radiation might also be used.  Today, treatment is very effective, with 95% of all testicular cancer patients surviving 5 years and 99% surviving 5 years when the cancer was localized at the time of diagnosis.  It should be noted, however, that concern exists regarding the development of other forms of cancer, such as leukemia, later in life.
Colorectal Cancer
Cancer of the colon and rectum (colorectal cancer) has a death rate second only to that of lung cancer.  In the most general sense, two types of tumors, carcinoma and lymphoma, can be found in both colon and rectum.  However, even within the most common form of colorectal cancer, there may subtle difference in type of tumors (or their origins) which influence the degree of potential spread and, thus, the nature of treatment itself.  Fortunately, when diagnosed in a localized state, colorectal cancer has a relatively high survival rate (90% when localized and 65% for all stages).
Risk Factors
Underlying the development of colorectal cancer are at least two potentially important areas of risk: genetic susceptibility and dietary patterns.  Genes have recently been discovered that lead to familial colon cancer and familial polyposis (abnormal tissue growth that occurs before the formation of cancer) and are believed to be responsible for the tendency of colorectal cancer to run in families.  Dietary risk factors include diets that are high in saturated fat from red meat and low in fruits and vegetables, which contain antioxidant vitamins and fiber.  In regard to fiber’s ability to prevent colorectal cancer, however, the ability of dietary fiber, when taken in supplement form, is in question.  In addition, an association between colorectal polyps and smoking has been identified.
Prevention
Small outpouching in the lower intestinal tract wall, called polyps, are frequently important in the eventual development of colorectal cancer.  Prompt removal of polyps has been shown to lower the risk of colorectal cancer.  Further, some evidence indicates that the development of colorectal cancer may be prevented or slowed through regular exercise, the regular use of aspirin, an increase in dietary calcium intake, and long-term folic acid supplementation.  Additionally, oral contraceptive use may be protective for women.
Again, routine screening for colorectal cancer should be considered a form of prevention, much as PSA testing is for prostate cancer and mammography is for breast cancer.
Early Detection
Symptoms of colorectal cancer including bleeding from the rectum, blood in the stool, and a change in the bowel habits.  In addition, a family history of inflammatory bowel disease, polyp formation, or colorectal cancer should make one more to symptoms.  In people over age 50, any sudden change in bowel habits that lasts 10 days or longer should be evaluated by a physician.  The American Cancer Society recommends preventive health care include digital (manual) rectal examination after age 40, a stool blood test after age 50, and sigmoidoscopy every 3 to 5 years and colonoscopy every 10 years after age 50.  At this time some experts are questioning the advisability of using sigmoidoscopy as the routine screening procedure for colorectal cancer in comparison to using colonoscopy, which can more effectively find distal (higher up in the colon) cancerous changes.
Although colonoscopy is currently the “gold standard” in the screening for colorectal cancer, new technologies are on the horizon.  Three alternatives include the PreGen-Plus test that identifies cancer-indicating DNA mutations appearing in stool samples; a yet-named blood test capable of identifying “loss of imprinting” (LOI) factor associated with a high risk for colorectal cancer; and CT colonography (CTC) that uses serial tomography to visualize the colon, thus eliminating the need to scope the colon.
Treatment
When  one or more of these screening procedures suggests the possibility of disease within the lower intestinal tract, a careful visual evaluation of the entire length of the colon will be undertaken.  During colonoscopy, areas of concern can be biopsied and the presence of a malignancy confirmed.  Upon diagnosis, a localized and noninvasive, malignancy will be removed surgically.  When an invasive tumor is identified, supportive treatment with radiation or chemotherapy is necessary.   Metastatic cancer requires chemotherapy.
Pancreatic Cancer
Pancreatic cancer is one of the most lethal forms of cancer, with a survival rate of only 4% 5 years after diagnosis.  Because of this gland’s important functions in both digestion and metabolic processes related to glucose utilization, its destruction by a malignancy leaves the body in a state incompatible with living.
In 2003 an estimated 30,700 new cases of pancreatic cancer were diagnosed and 30,000 deaths occurred.
Risk factors
Pancreatic cancer is more common in men than women, occurs more frequently with age, and develops most often in African American men.  Smoking is clearly a risk factor for this form of cancer, with smokers more than twice as likely to develop the disease.  Other risk factors have been tentatively suggested, such as chronic inflammation of the pancreas (pancreatitis), diabetes mellitus, alcohol-induced liver deterioration (cirrhosis), obesity, and high-fat diets.  Relatively little else is known about risk factors and, thus, prevention.
Prevention
Not smoking and abstaining from alcohol use are the most effective steps toward preventing this form of cancer.  Further, reducing the risk of type 2 diabetes mellitus, through weight loss and exercise, would also make an important contribution to prevention.  Annual medical examinations are, of course, associated with overall cancer prevention.
Early Detection
Early detection of this cancer is difficulty because of the absence of symptoms until late in its course.  Perhaps for people with a history of chronic pancreatitis, physicians might consider routine ultrasound assessment or computerized axial tomography scans (CAT scans).  Once symptoms appear, a biopsy will be performed.
Treatment
At this time there is not effective treatment for pancreatic cancer.  Surgical removal of malignant sites within the gland, in addition to radiation and chemotherapy, is usually tried.  Certainly, if a particular patient with pancreatic cancer qualifies, enrollment in a clinical trial would be worth consideration.
Lymphatic Cancer
An estimated 61,000 new cases of lymphoma (7,600 cases of Hodgkin’s disease and 53,400 cases of non-Hodgkin’s lymphoma) were diagnosed in 2003.  The number of deaths from both forms of lymphoma was near 31,900.  The incidence of Hodgkin’s disease has declined over the last 25 years, while the incidence of non-Hodgkin’s disease has nearly doubled.
Risk Factors
Risk factors for lymphoma are difficulty to determine.  Some possible factors are a general reduction in immune protection, exposure to toxic environmental chemicals such as pesticides and herbicides, and viral infections.  The virus that causes AIDS (HIV) is a leukemia/lymphoma virus that was initially called HTLV-III (human T-cell leukemia/lymphoma virus-type III).  A related leukemia/lymphoma virus, HTLV-I, is also suspected in the development of lymphatic cancer.
Prevention
Beyond limiting exposure to toxic chemicals and sexually transmitted viruses, few recommendations can be made about prevention.  Again, early detection and diagnosis can serve as a form of prevention, since early-stage cancer is more survivable than advanced disease.
Early Detection
Unlike other cancers, the early symptoms of lymphoma are diverse and similar to symptoms of other illnesses, most of which are not serious.  These symptoms include enlarged lymph nodes (frequently a sign of any infection that the immune system is fighting), fever, itching, weight loss, and anemia.
Treatment
Although surgery (beyond a biopsy) is usually not associated with the treatment of lymphoma, a variety of other therapies are employed.  Depending on the stage and type of lymphoma, therapy may involve only radiation treatment of localized lymph nodes, as is seen in non-Hodgkin’s lymphoma.  Radiation combined with chemotherapy is generally used in the treatment late-stage non-Hodgkin’s lymphoma.  More recently, other therapies, including more aggressive chemotherapy, monoclonal antibody therapy, and bone marrow and stem cell transplantation, have been employed.
After completion of therapy, one-year survival rates for Hodgkin’s disease are near 95% and near 77% for non-Hodgkin’s lymphoma.  By the end of 5 years, these rates have dropped to 84% and 55%, respectively.  Lower rates of survival are seen at 10 years and beyond.
Skin Cancer
Thanks largely to our desire for a fashionable tan, many teens and adults have spent more time in the sun (and in tanning booths) than their skin can tolerate.  As a result, skin cancer, once common only among people who had to work in the sun, is occurring with alarming frequency.  In 2003, nearly 1.3 million Americans developed basal or squamous cell skin cancer and 54,200 cases of highly dangerous malignant melanoma were diagnosed.
Deaths from skin cancer do occur, with 9,600 estimated in 2002.  More than 80% of these deaths were the result of malignant melanoma.
Risk Factors
Severe sunburning during childhood and chronic sun exposure during adolescenes and younger adulthood are largely responsible for the “epidemic” of skin cancer being reported.  The current emphasis on screening for skin cancer may also be increasing the incidence of early-stage cancer being reported.  Occupational exposure to some hydrocarbon compounds can also cause skin cancer.
Prevention
Prevention of skin cancer should be a high priority for people who enjoy the sun or must work outdoors.  The use of sunscreen with an a sun protection factor (SPF) of 15 or greater is very important.  In addition, parents can help their children prevent skin cancer later in life by restricting their outdoor play from 11:00 A.M to 2:00 P.M., requiring them to wear hats that shade their faces, and applying a sunscreen with an SPF of 15 on them regardless of skin tone.  A recent evaluation of sunscreen effectiveness studies by Sloan-Kettering Cancer Center, however, suggests that sunscreen provide little protection against the deeply penetrating UV-A rays associated with the development of melanoma in susceptible people, and less protection than once thought against the UV-B rays associated with burning and wrinkling of the skin.  Practicing dermatologists nonetheless continue to recommend their use.  Regardless of the extent to which sunscreens provide protection, users are reminded that the level of protection provided is not doubled by simply doubling the SPF – for example, a sunscreen carrying an SPF of 30 does not provide twice the protection provided by a product with an SPF of 15.  Therefore, the compliant use of a SPF-15 product is deemed not only appropriate, but may also save money over the more expensive products with a higher SPF rating.
Early Detection
Although many doctors do not emphasize this point enough, the key to the successful treatment of skin cancer is early detection.  For basal cell or squamous cell cancer, a pale, waxlike, pearly nodule or red, scaly patch may be the first symptom.  Other types of skin cancer may be indicated by a gradual change in the appearance of an existing mole.  A physician should be consulted if such a change is noted.  Melanoma usually begin as a small, molelike growth that increases progressively in size, changes color, ulcerates, and bleeds easily.  To help detect melanoma, the American Cancer Society recommends using the guidelines below:
A is for asymmetry.
B is for border irregularity.
C is for color (change).
D is for a diameter greater than 6 mm.
E is for elevation (raised margins).
Most recently, a relationship between the presence of abnormal moles, called dysplastic nevi (flat, irregularly shaped, mottled in color, with irregular edges), and the risk of developing malignant melanoma has been established.  By counting these “indicator moles,” physicians can judge the relative risk of developing this serious form of skin cancer before it first appears.
Treatment
When nonmelanoma skin cancer is found, an almost 100% cure rate can be expected.  Treatment of these skin cancers can involve surgical removal by burning or freezing, or destruction using x-ray therapy.  When the more serious melanomas are found at an early stage, a high cure rate (95%) is accomplished using the same techniques.  However, when malignant melanomas are more advanced, extensive surgery and chemotherapy will be necessary.  The 5 year survival rate for regionalized forms of the disease drops to 60%, and unfortunately, long-term disease recovery is uncommon (14%).
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