Non-mammary metastases to the breast and axilla: a study of 85 cases

Abstract

Non-mammary metastases to the breast and axilla are rare occurrences. However, they are important diagnostic considerations as their treatment and prognosis differ significantly from primary breast cancer. Between 1990 and 2010, we identified a total of 85 patients, 72 women and 13 men, with non-mammary malignancies involving the breast, axilla, or both. The tumor types consisted of carcinoma (58%), melanoma (22%) and sarcoma (20%). Ovary was the most common site of origin for carcinoma, and metastatic high-grade ovarian serous carcinoma was most frequently misdiagnosed as a primary breast carcinoma. Melanoma was the single most common non-carcinomatous tumor type to involve the breast and/or axilla, and uterine leiomyosarcoma was the most common type of sarcoma. Most patients (77%) had other metastases at the time of diagnosis of the tumor, but in 11% the breast or axillary lesion was the first presentation. Without a clinical history, non-mammary metastases were difficult to diagnose because the majority of cases presented with a solitary nodule and lacked pathognomonic pathologic features. There were, however, certain recurrent histological findings identified, such as the often relatively well-circumscribed growth pattern of the metastatic lesion surrounded by a fibrous pseudocapsule, and the absence of an in situ carcinoma. Overall, these patients had poor survival; 96% of patients with follow-up available are dead of disease, with a median survival of 15 months after the diagnosis of the breast or axillary lesion. This finding emphasizes the need to accurately identify these tumors as metastases in order to avoid unnecessary procedures and treatments in these patients. Keywords: axilla; breast; extramammary Metastases to the breast and axilla are rare and account for approximately 2% of all mammary malignancies. 1,2 The most common metastatic lesion to involve the breast is a metastasis from a contralateral mammary cancer. 1,2 If hematologic malignancies are also excluded, the number of non-mammary metastases drops to well below 1%. 1,3 Owing to the frequency of primary breast cancers and the rarity of non-mammary tumors involving the breast, a newly discovered lesion in the breast or axilla is usually presumed to be a primary or metastatic breast carcinoma. However, the recognition of non-mammary metastases to the breast and axilla is very important, as both the treatment and prognosis differ significantly. Materials and methodsAfter obtaining approval by our Institutional Review Board, we searched the pathology database of Memorial Sloan-Kettering Cancer Center between the years 1990-2010 for patients with non-mammary metastases to the breast and axilla. Hematologic malignancies were excluded, as they are systemic diseases. The medical records and pathology slides, when available, were reviewed and the clinicopathologic characteristics were recorded. Patient age, gender, primary tumor site, the presence of other metastases, laterality, number of lesions, interval from primary tumor diagnosis to breast/ a...

Comparison of metastatic neuroendocrine neoplasms to the breast and primary invasive mammary carcinomas with neuroendocrine differentiation

“…Since metastatic neuroendocrine neoplasms to the breast are very rare, we also included eight additional recently published cases of metastatic neuroendocrine neoplasms to the breast from the anatomic pathology database of Memorial Sloan-Kettering Cancer Center (New York, NY, USA). 4 The clinical histories, including results of imaging studies and prior pathology reports, were reviewed in detail to ascertain the site of origin of metastatic neuroendocrine neoplasms to the breast. Cases for which a definite primary site of origin could not be determined with certainty were excluded from the study.…”

“…Metastases to the breast are unusual, comprising less than 1% of all malignant neoplasms of the breast. [1][2][3][4][5] The majority of the metastatic lesions originate from the contralateral breast or hematopoietic malignancies. 1,2,5 Stomach, kidney, ovary, lung, and skin are the other common primary sites.…”

“…1,2,5 Stomach, kidney, ovary, lung, and skin are the other common primary sites. [1][2][3][4][5] Metastatic neuroendocrine neoplasms to the breast are rare and comprise only 1-2% of all metastatic tumors to the breast. To the best of our knowledge, less than 50 cases have been described to date, primarily in the form of isolated case reports and rare case series.…”

Unilateral breast edema due to subclavian vein compression

“…In general, they do not cause cutaneous nor papillary retraction and tend to be more frequently multiple or bilateral in relation to primary breast neoplasms. The radiographic appearance is of one or more round and well-defined nodules, without microcalcifications in the subcutaneous tissue -except for rare exception, as in cases of ovarian cancer 1,3,6,7 . Mastitis usually occurs among young women and breastfed infants, but may also affect immunosuppressed women.…”

Metastatic melanoma in breast imaging: A case report

“…[16,17] S100 is expressed in 95% of melanomas but is not specific as it is present in 50% of breast cancers; [15] for this reason, the IHC panel normally includes HMB45…”