Handbook of Psychology

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268 Psychosocial Oncology


“nger -like projections from a cancer that is reminiscent of
a crab.
Although cancer is often thought of as being a single dis-
ease, it is actually a term used to describe in excess of 200
different diseases. The differing types of cancers can be clas-
si“ed into “ve major groups: carcinoma(a cancerous tumor,
or malignant neoplasm, that originates in the surface tissue of
body organs), sarcoma(a cancerous tumor originating in the
bone, cartilage, muscle, “brous connective tissue, or fatty
tissue);myeloma(a malignant neoplasm originating in the
plasma cells of the bone marrow), lymphoma(a cancerous
tumor originating in the lymph system), and leukemia(cancer
originating in the blood-forming tissue).
All types of cancer have one characteristic in common„
the uncontrollable growth and accumulation of abnormal
cells. Normal cells behave according to preprogrammed
genetic rules unique to a particular cell type (e.g., skin,
blood, brain). They divide, mature, die, and are replaced ac-
cording to this systematic plan. Cancer cells, on the other
hand, do not follow biological rules„they divide more
rapidly than usual, grow in a disorderly fashion, and do not
properly mature.
Immortal cells are those cancer cells that are not
•programmedŽ to know when to stop dividing or die. They
can destroy normal surrounding tissue and have a propensity
to spread throughout the body. This abnormal process of
malignancy leads to the accumulation of cancer cells that
eventually form a mass or tumor. If the proliferation of this
cancerous growth is not halted, the abnormal cells can extend
to surrounding areas and metastasize or spread to form tu-
mors in other parts of the body. Eventually, the organs and
body systems that are affected cannot perform their proper
functions which can lead to death.


Cancer Statistics


All of the statistics provided in this section were obtained
from the American Cancer Society (2000) and Greenlee,
Murray, Bolden, and Wingo (2000). During the year 2000,
over 1.2 million new cases of invasive cancer are expected to
have been diagnosed in the United States. This estimate does
not include noninvasive cancers such as basal and squamous
cell skin cancers, of which 1.3 million new cases will be di-
agnosed during this year. Since 1990, approximately 13 mil-
lion new cancer cases have been diagnosed. More than 1,500
people are expected to die each day from cancer this year. It
is the second leading cause of death in the United States, sur-
passed only by heart disease„1 of every 4 deaths in the
United States is cancer-related.


Gender

Rates for the year 2000 indicate similar levels of incidence for
men and women across all cancer types, the major difference
being the incidence of breast cancer. For men, the most com-
mon cancers are expected to be cancers of the prostate, lung
and bronchus, and colon and rectum. Accounting for 29% of
the new cancer cases (i.e., 180,400 new cases), prostate can-
cer is the leading site for cancer incidence among men.
Among women, the three most commonly diagnosed
cancers are breast, lung and bronchus, and colon and rectum.
Collectively, these three sites will account for over 50% of all
new cases of cancer in women. However, by itself, breast
cancer is expected to account for over 180,000 new cancer
cases (30%) in the year 2000.

Race

The incidence of cancer varies widely among differing racial
and ethnic groups in the United States. In general, cancer
incidence rates are highest among African Americans. For ex-
ample, they are approximately 60% more likely to develop
cancer as compared to Hispanics and Asian Americans/Paci“c
Islanders and twice as likely to develop cancer than among
American Indians. African American men are also about 33%
more likely to die from cancer than are Whites and twice as
likely to die of cancer as compared to Asian Americans/Paci“c
Islanders, Hispanics, and American Indians.
The incidence of female breast cancer is highest among
White women and lowest among American Indian women.
However, African American women are more likely to die of
breast cancer (as well as colon and rectum cancer) than are
women of any other racial and ethnic group.

Improvement in Survival Rates

Approximately 8.4 million Americans who have a history of
cancer are alive today. Some of these individuals are consid-
ered to be •cured,Ž whereas the others continue to show evi-
dence of cancer. Although there has been an increase in the
mortality rates in the United States during the second half of
the twentieth century, this is largely due to the increase in
lung cancer. When deaths attributed to this cancer type are
excluded, cancer mortality actually shows a decrease of ap-
proximately 16% since 1950.
More important as an indicator that there is signi“cant
progress in the •war on cancerŽ is the improvement in sur-
vival rates. Early in the twentieth century, few patients diag-
nosed with cancer were expected to live. In the 1930s, the
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