Discuss clinical and pathologic findings that are useful in the diagnosis and treatment of a patient with breast cancer. (<250 words)
Since breast cancer will affect at least one woman in 10 in the U.S., it is important to recognize this disease. Most breast "lumps" are benign, with fibrocystic disease being the most common, but about 10% of lumps turn out to be cancer, so early detection is important. Risk factors for cancer that would prompt thorough investigation include age >25, history of breast cancer in a maternal close relative, nulliparity, atypical epithelial hyperplasia with fibrocystic disease, early menarche and/or late menopause, and obesity. Physical examination findings that suggest a carcinoma include a firm, hard, non-movable mass, skin dimpling or retraction, nipple eczematoid appearance with Paget's disease, inflammatory changes with reddened and roughened skin, and enlarged, firm axillary lymph nodes. Discreet, freely movable masses are likely to be benign, such as a fibroadenoma.
Once a carcinoma is suspected, mammography can help to localize a lesion and substantiate possible malignancy from the appearance of an irregular density with calcifications. Fine needle aspiration cytology and/or biopsy can then be done. The histologic findings of atypical, hyperchromatic cells with increased N/C ratio are consistent with carcinoma. Most breast cancers are ductal (90%), while only 10% are lobular in origin. If the carcinoma is still in situ, then the prognosis is better. Ductal carcinomas are likely to become invasive if not treated early. Lobular carcinomas are often bilateral. The tumor tissue should be analyzed for the presence of estrogen receptors that indicate responsiveness to hormonal manipulation.
Discuss the demographics, risk factors, histologic patterns, and prognostic features of breast cancer in women. (<300 words) Breast cancer is more common in American women than in Japan or developing nations. About 1 in 10 American women will develop breast cancer, which accounts for 20% of all cancer deaths in women. Risk factors for development of breast cancer include a family history (mother, sister, aunt) of breast cancer, early menarche with late menopause, nulliparity, age over 30 with first child, age greater than 25, increased exogenous or endogenous estrogen, previous breast cancer or endometrial carcinoma, and fibrocystic disease with atypical epithelial hyperplasia. Histologically, most breast cancers are carcinomas. About 90% arise from ductular epithelium while 10% arise from lobular epithelium. These carcinomas can be further subdivided into in-situ and invasive types. The former include intraductal carcinoma, lobular carcinoma in-situ, and intraductal papillary carcinoma. Invasive carcinomas include infiltrating (invasive) ductal carcinoma or lobular carcinoma, medullary carcinoma, colloid carcinoma, and tubular carcinoma. In addition, Paget's disease of nipple is a form of ductal carcinoma that extends to the dermis. Sarcomas of the breast are uncommon and include cystosarcoma phyllodes which has stromal and epithelial components, either or both of which are malignant. Features of breast cancers that imply a worse prognosis include lack of estrogen receptors, extension of tumor to dermal lymphatics of overlying breast skin to produce an "inflammatory" carcinoma, axillary lymph node metastases, distant hematogenous metastases, and increased nuclear anaplasia that can be measured by increased proliferative rate and aneuploidy with flow cytometry. A lobular carcinoma in-situ implies at least a 50% chance of bilaterality and a 20% chance of a subsequent invasive carcinoma. Clinical findings of more advanced carcinomas include a larger tumor size, a rock-hard and non-mobile mass, skin retraction or dimpling or ulceration or "orange peel" appearance, lymphedema, and palpable lymph nodes. |