242节默克诊疗学第十八章妇科与产科对照版本

During puberty, enlargement of the male breast is normal and is usually transient. Similar changes may occur during senescence. Gynecomastia in both sexes may be caused by various diseases (especially of the liver), by drug therapy (eg, estrogens, reserpine, digitalis, isoniazid, spironolactone, Ca channel blockers, ketoconazole, theophylline, cimetidine, metronidazole, methadone, antineoplastic drugs), by marijuana use, and, less commonly, by endocrine disorders. Ultrasonography of the testis can detect estrogen-secreting testicular tumors, and CT or MRI of the abdomen can detect estrogen-secreting adrenal tumors.
These benign tumors usually develop in young women, often in teenagers, and may be mistaken for cancer. However, they tend to be more circumscribed and mobile and, when palpated, may feel like small, slippery marbles. Fibroadenomas can usually be excised using a local anesthetic, but they frequently recur. After a patient has had several fibroadenomas established as benign, she may decide against having subsequent ones excised. Other benign solid breast masses include fat necrosis and sclerosing adenosis, which can be diagnosed only by biopsy.
In some cases, the cancer or benign tumor causing the discharge can be palpated. In other cases, routine or contrast ductographic mammography can help locate the tumor. If these examinations do not detect breast cancer, the cause of the discharge is probably benign, and a nipple-flap duct resection, usually performed as an outpatient procedure using a local anesthetic, can eradicate the symptom and relieve the patient's anxiety. A milky discharge (galactorrhea) in a woman who has not just given birth should prompt an endocrine evaluation Galactorrhea underAnterior Lobe DisordersinCh.7).
Other causes of mastalgia are thought to be primarily hormonal. Restricting intake of methylxanthine-containing substances (eg, coffee) is ineffective. For most patients, mastalgia remits spontaneously after months or years. Danazol (an attenuated androgen with usually mild androgenic adverse effects) 100 to 400 mg/day po for3 to 6mo or tamoxifen (an antiestrogen with very few adverse effects) 10 mg bid po for3 to 6mo can relieve mastalgia. Because these drugs have long-term adverse effects, their use should be limited to a short course in patients with unusually severe symptoms; tamoxifen can probably be given safely, especially to postmenopausal women, for up to 5 yr. Any unexplained bleeding must be investigated to check for endometrial cancer.
Breast infections are extremely rare except during the postpartum period or after trauma. If infection occurs under other circumstances, an underlying disorder, such as cancer, should be sought promptly.
Nipple discharge is not necessarily abnormal, even among postmenopausal women. Cancer is the cause in < 10% of patients (seePaget's Disease,below). The gross appearance of the discharge is of little help in diagnosing an underlying cancer; in one study, only guaiac-positive secretions were associated with breast cancer. The most common cause of a bloody discharge is an underlying intraductal papilloma.
(See alsoChs. 142,143,and144.)
In situ carcinomais contained entirely within the breast duct, with no invasion of adjacent normal tissues. Once fairly uncommon, it now accounts for > 15% of all breast cancers diagnosed in theUSA, and the proportion is much higher in younger age groups. This increase is the result of better screening.
Mastalgia is the most common benign breast disorder. In premenopausal women, pain may occur with the menstrual cycle as a more intense variation of premenstrual discomfort. In some cases, the pain is associated with easily palpated cysts and can be relieved by aspirating the cyst with a fine-gauge needle. The aspirated fluid need not be examined cytologically in women < 30 yr, but the color, volume, and disappearance or recurrence of the cyst after aspiration should be recorded. Cancer in the wall of a cyst, although extremely rare, may be suspected if the fluid is bloody or reaccumulates rapidly (within 12 wk) after aspiration. In such cases, the entire cyst should be excised.
Gynecomastia may be unilateral or bilateral. Most of the argement is usually due to proliferation of stroma, not of breast ducts. The patient may experience some tenderness, which is generally associated with benign causes. In most cases, no specific treatment is needed because gynecomastia remits or disappears after the drug is withdrawn or the underlying disorder is treated. Hormonal therapies have not been validated. Surgical removal of the excess breast tissue (eg, suction lipectomy alone or with cosmetic surgery) is occasionally the only effective treatment.