Invasive Carcinoma (% of

Carcinomas)

Average Size of Invasive

Carcinomas

Carcinomas with Lymph

Node Metastases

DCIS (% of

Carcinomas)

LCIS (% of

Carcinomas)

Palpable mass 94% 2.4 cm 58% •2% 4%

Mammographic density 94% 1.1 cm 14% •4% 2%

Mammographic calcifications 26% 0.6 cm •6% 71% 3%

Based on the results of 235 carcinomas diagnosed in 914 women undergoing diagnostic biopsies at Brigham and Women's Hospital over a 6-month period in 2001.

Mammographic lesions were nonpalpable.

DCIS, ductal carcinoma in situ; LCIS, lobular carcinoma in situ.

compared to 60% of masses in women over age 50 ( Fig. 23-4 ). The most commonly encountered lesions are invasive carcinomas, fibroadenomas, and cysts. Approximately 50% of

carcinomas arise in the upper outer quadrant, 10% in each of the remaining quadrants, and about 20% in the central or subareolar region.

Nipple discharge is a less common presenting symptom but is of concern when it is spontaneous and unilateral. A discharge produced by manipulating the breast is normal and unlikely to

be associated with a pathologic lesion. A milky discharge (galactorrhea) is associated with increased production of prolactin (e.g., by a pituitary adenoma), hypothyroidism, or endocrine

anovulatory syndromes. It can also occur in patients taking oral contraceptives, tricyclic antidepressants, methyldopa, or phenothiazines. Repeated nipple stimulation can also induce

lactation (e.g., this method is sometimes used by women who wish to breast-feed adopted infants). Milky discharge has not been associated with malignancy. Bloody or serous discharges

are most commonly associated with benign lesions but, rarely, can be due to a malignancy. A normal bloody discharge can also occur during pregnancy, possibly due to the rapid formation

of new lobules. The risk of malignancy with discharge increases with age. Discharge is associated with carcinoma in 7% of women younger than 60 years and in 30% of women older than

60 years. The most common etiologies for discharge are a solitary large duct papilloma, cysts, or carcinoma ( Fig. 23-4 ). Carcinomas presenting as nipple discharge not associated with a

palpable mass are equally divided between invasive and in situ carcinomas.[10] There is considerable interest in developing the cytologic examination of induced nipple discharge into a

screening test for breast cancer.

Mammographic screening was introduced in the 1980s as a means to detect small, nonpalpable breast carcinomas not associated with breast symptoms. The sensitivity and specificity of

mammography increase with age. As the dense, fibrous interlobular tissue of the young woman is replaced by the fatty tissue of the older woman, it becomes easier to detect small masses

and calcifications. Also, with increasing age, benign lesions become less frequent and malignant lesions become more frequent. Screening is generally recommended to start at age 40.

Younger women usually undergo mammography only if they are at high risk for developing carcinoma, owing either to a prior palpable cancer or to a strong family history. Despite the

screening of women at high risk of breast cancer, only 12% of mammographic lesions in women

Figure 23-4Frequency of benign and malignant breast lesions diagnosed after biopsy by clinical presentation and age. (Based on 914 women who underwent diagnostic breast surgery at

Brigham and Women's Hospital, Boston, from January to June 2001.)

Figure 23-5Recurrent subareolar abscess. When squamous metaplasia extends deep into a duct, keratin becomes trapped and accumulates. If the duct ruptures, the ensuing intense

inflammatory response to keratin results in an erythematous painful mass. A fistula tract may burrow beneath the smooth muscle of the nipple to open at the edge of the areola.

Figure 23-6Mammary duct ectasia. Chronic inflammation and fibrosis surround an ectatic duct filled with inspissated debris. The fibrotic response can mimic the irregular shape of

malignant carcinomas on palpation or mammogram.

Figure 23-7Apocrine cysts. Cells with round nuclei and abundant granular eosinophilic cytoplasm, resembling the cells of normal apocrine sweat glands, line the walls of a cluster of

small cysts. Secretory debris, frequently with calcifications, is often present. Groups of cysts are common findings associated with clustered mammographic calcifications.

Figure 23-8 A, Normal. A normal duct or acinus has a single basally located myoepithelial cell layer (cells with dark, compact nuclei and scant cytoplasm) and a single luminal cell layer

(cells with larger open nuclei, small nucleoli, and more abundant cytoplasm). B, Epithelial hyperplasia. The lumen is filled with a heterogeneous population of cells of different

morphologies, often including both luminal and myoepithelial cell types. Irregular slitlike fenestrations are prominent at the periphary.

Figure 23-9Sclerosing adenosis. The involved terminal duct lobular unit is enlarged, and the acini are compressed and distorted by the surrounding dense stroma. Calcifications are often

present within the lumens. Although this lesion is frequently mistaken for an invasive carcinoma, unlike carcinomas, the acini are arranged in a swirling pattern, and the outer border is

usually well circumscribed.

Figure 23-10Complex sclerosing lesion (radial scar). There is a central nidus consisting of small tubules entrapped in a densely fibrotic stroma surrounded by radiating arms of epithelium

with varying degrees of cyst formation and hyperplasia. These lesions typically present as an irregular mammographic density and closely mimic an invasive carcinoma.

Figure 23-11Intraductal papilloma. A central fibrovascular core extends from the wall of a duct. The papillae arborize within the lumen and are lined by myoepithelial and luminal cells.

Figure 23-12 A, Atypical ductal hyperplasia. A duct is filled with a mixed population of cells consisting of oriented columnar cells at the periphery and more rounded cells within the

central portion. Although some of the spaces are round and regular, the peripheral spaces are irregular and slitlike. These features are highly atypical but fall short of a diagnosis of DCIS.

B, Atypical lobular hyperplasia. A population of monomorphic small, rounded, loosely cohesive cells partially fill a lobule. Some intracellular lumina can be seen. Although the cells are

morphologically identical to the cells of LCIS, the extent of involvement is not sufficient for this diagnosis.

TABLE 23-2-- Breast Lesions and Relative Risk of Developing Invasive Carcinoma

Pathologic Lesion

Date: 2016-04-22; view: 626