Mammary Endocrine Ductal Carcinoma in Situ: A Case Report

Endocrine differentiation represents a pathway of neoplastic development available to a range of breast cancers. This pattern occurs in tumors with different morphological appearances as ductal carcinoma in situ (DOS), mucinous carcinoma, a variant of lobular carcinoma, and low-grade invasive ductal carcinoma. Endocrine ductal carcinoma in situ is an uncommon entity. It occurs in older women with a mean age of 70 years. Histologically it shows expansile intraductal growth forming solid sheets and festoons transversed by delicate fibrovascular septa. Conventional microscopy permits the diagnosis in most cases. Specialized techniques such as immunohistochemistry and electron microscopy can serve as the basis of diagnosis in the absence of the appropriate morphological features. We present a 68-year-old female with a 1.5-cm firm mobile nodule of the left breast. Mammography and ultrasounds showed a 15 x 15-mm circumscribed solid lobulated nodule. The mass was excised and pathology was positive for endocrine DCIS. Although endocrine DCIS has a biologic marker profile similar to that of well-differentiated or noncomedo DCIS it may constitute a different histogenetic pathway of carcinogenesis in the breast. The tumor may exhibit the invasive characteristics of a neuroendocrine neoplasm. Larger studies and longer follow-up are needed for the determination of the clinical behavior.

Primary neuroendocrine tumor of the breast

Adult neuroendocrine tumors may present with a wide range of clinical symptoms that share specific ultrastructural and biochemical features. A 63-year-old post-menopausal female patient was admitted to the hospital with a mass in her right breast and the diagnosis was primary neuroendocrine tumor of the breast. Although neuroendocrine tumors can originate in various parts of the body and breast carcinoma with neuroendocrine differentiation has been described, primary neuroendocrine tumor of the breast is very unusual. This case is now presented and the current literature is reviewed.

Endocrine ductal carcinoma in situ (E-DCIS) of the breast: a form of low-grade DCIS with distinctive clinicopathologic and biologic characteristics

Endocrine ductal carcinoma in situ (E-DCIS), first characterized by Cross et al. in 1985, is an uncommon entity, and there is little information on its pathobiologic features and natural history in the literature. This report describes the largest series of 34 cases: 14 cases were pure in situ (group A), and 20 were accompanied by an invasive component (group B). All except three patients were over the age of 60 years, with the mean being 69.5 years for group A and 72.6 years for group B. Except for six patients in group A who had nipple discharge, all had a breast mass. On follow-up, one of five group A patients developed local recurrence 5 years after mastectomy, and two of seven group B patients developed another invasive primary in the contralateral breast. Histologically, E-DCIS showed expansile intraductal growths forming solid sheets and festoons traversed by delicate fibrovascular septa. Accumulation of basophilic mucin might be found within the growth and the fibrovascular septa. There were variable degrees of stromal sclerosis. In some cases, the solid intraductal cellular proliferations were focally punctuated by microglandular spaces and rosettes. Comedo necrosis was absent. Intraductal papillomas were found in the immediate vicinity of the tumors in 18 cases and invariably showed pagetoid involvement by E-DCIS. Pagetoid spread into the adjacent ducts and ductules was also a common feature (17 cases). The tumor cells were polygonal, oval, or spindly, often with eccentrically placed, bland-looking, ovoid nuclei and abundant eosinophilic granular cytoplasm. Intracellular mucin was commonly demonstrable. Immunostaining for myoepithelium using muscle-specific actin antibody confirmed the in situ nature of the E-DCIS component. The majority of tumor cells showed strong staining with the neuroendocrine markers chromogranin, synaptophysin, and neuron-specific enolase (monoclonal). Immunostaining also dramatically highlighted the pagetoid spread into the papillomas and ductules by outlining the tumor cells between the negatively stained residual ductal epithelium and myoepithelium. All cases were immunoreactive for estrogen and progesterone receptor, but not p53 and c-erbB2. The Ki-67 index was < 5%. Ultrastructural studies on four cases showed many dense-core neurosecretory granules and larger mucigen granules. In group B cases, the invasive component, which comprised 5-95% of the tumor, included colloid carcinoma, 12; "carcinoid" tumor, 3; mixed "carcinoid"/colloid carcinoma, 4; and small cell neuroendocrine carcinoma, 1. Neuroendocrine markers were also consistently demonstrable in the invasive component. In conclusion, E-DCIS is predominantly a disease of older women that is frequently accompanied by papillomas in the vicinity and may present as nipple discharge (an uncommon presentation in the usual forms of DCIS). It can mimic epitheliosis histologically, but the pagetoid spread is a helpful clue to its neoplastic nature. The bland nuclear morphology, lack of necrosis, and biologic marker profile suggest that E-DCIS is a form of low-grade DCIS despite its solid growth pattern. The invasive carcinomas associated with E-DCIS are also neuroendocrine programmed rather than the usual types of ductal carcinomas, suggesting that E-DCIS represents a biologically distinctive category of DCIS.