stages because of its location in the mucosal and submucosal glands sur-
rounding the urethra. The main gland is sensitive to androgens, whereas the
periurethral glands are sensitive to androgens and estrogens. Acid phos-
phatase and prostatic-specific antigen (PSA) levels are used in the diagnosis
of prostatic carcinoma and its metastasis.
Carcinoma of the breast occurs in about 1 of 10 females in the United
States. By definition, a carcinoma is ductal in origin (answers a and e).
Carcinoma of the breast metastasizes to the brain, lungs, and bones. The
easy access of tumor cells to the extensive axillary blood supply and lym-
phatic drainage facilitates the spread of the cancer into the blood and
lymph supplies. Self-examination and mammography are urged in an
attempt to increase early diagnosis, which has reduced mortality of this
disease.
Germ cell tumors (answer d)of the testes (testicular neoplasms) are
classified as seminomas (germinomas) of pure germ cells and more hetero-
geneous cell types (e.g., teratomas and embryonal carcinomas).
241.The answer is c.(Rubin, pp 942–943.)To a minor extent, the uterine
cervical stroma changes during each reproductive cycle; however, during
pregnancy (especially parturition) there is a thinning of the uterine stroma.
This results in eversions (mistakenly called “erosions”), which are sites of
exposed uterine columnar epithelium in the acidic, vaginal milieu. These
sites often become reepithelialized as stratified epithelium (squamous
metaplasia) and are believed to be the location of cancerous transformation
in the cervix. As part of the process of reepithelialization, the openings of
cervical mucous glands are obliterated, which results in the formation of
nabothian cysts.
242.The answer is c.(Young, pp 337–339. Junqueira, pp 429, 431.)The
organ shown in the light micrograph is the seminal vesicle that produces
fructose, ascorbic acid, prostaglandins, and proteins responsible for semen
coagulation. The seminal vesicle produces about 50% of the seminal fluid
on a volume basis and comprises most of the ejaculate. The wall consists of
smooth muscle and the mucosa of anastomosing “villus-like” folds. In
comparison, the prostate (answers a and d)is composed of 15 to 30 tubu-
loalveolar glands surrounded by fibromuscular tissue with concretions in
the lumina. The prostate secretes a thin, opalescent fluid that contributes
376 Anatomy, Histology, and Cell Biology