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%).
