Diagnosis and natural history of extramammary tumors metastatic to the breast

Abstract

Background: In patients with known extramammary malignancies, metastatic disease should be considered in the differential diagnosis of a breast mass.

Study design: Retrospective review.

Results: From January 1, 1980 to December 31, 1992, nine women (ages 25 to 67 years) were identified with breast masses, the biopsies of which proved to be metastatic from other sites. All patients presented with palpable breast masses. Mammograms were obtained in five patients; all demonstrated the palpable abnormality. Two of three mammograms showing multiple nodules were evaluated as suggestive of benign disease. In three patients, breast metastases were the presenting symptom of an occult primary tumor. The remaining six patients were diagnosed with metastatic disease in the breast from ten months to 15 years after the initial diagnosis (mean of 5.5 years) of an extramammary malignancy. One-half of the patients presented five or more years after the initial diagnosis. Breast metastases were associated with disseminated metastatic disease in eight of the nine patients. Six patients died after a mean interval of 8.2 months (range of 3.5 to 35 months) from diagnosis of breast metastases. One patient was unavailable for follow-up evaluation and is presumed dead.

Conclusions: Metastatic disease should be considered in the differential diagnosis of a palpable breast mass, particularly if there is a history of extramammary malignancy. The presence of multiple or bilateral well-circumscribed nodules may suggest a benign process on mammography. Breast metastasis is usually indicative of diffuse metastatic disease and a poor prognosis. Biopsy and careful review of previous pathologic material assures prompt treatment and avoids an unnecessary radical operation.