A Case Series of Breast Metastases from Different Extramammary Malignancies and Their Literature Review

Abstract

Metastasis to the breast from all other primary sites is unusual. Twelve patients were diagnosed between 2007 and 2017 at National Cancer Institute, Mexico. Solitary or multiple masses, round or oval, and hypoechoic and solid lesions with posterior acoustic shadowing were patterns commonly reported in these patients; other arrangements include diffuse involvement of the breast simulating an inflammatory carcinoma. The development of a breast metastasis is revealed, in our experience, as a negative prognostic factor. Thus, the radiologist should know about the varied appearance of metastatic breast lesions and provide radiopathological correlations when available.

Metastatic breast tumors from extramammary malignancies: a case series

“…indicated that metastatic breast tumors might have different imaging features depending on how primary malignant tumors metastasize, hematogenously or lymphatically [ 7 ]. According to the report, hematogenously metastasized tumors, typically head and neck cancers such as thyroid cancer [ 3 ], often form well-defined masses under the skin or near the parenchyma of the mammary gland, where blood flow is abundant. On the other hand, lymphatically metastasized tumors, typically gastrointestinal and gynecological cancers [ 3 ], appear with unclear boundaries.…”

“…According to the report, hematogenously metastasized tumors, typically head and neck cancers such as thyroid cancer [ 3 ], often form well-defined masses under the skin or near the parenchyma of the mammary gland, where blood flow is abundant. On the other hand, lymphatically metastasized tumors, typically gastrointestinal and gynecological cancers [ 3 ], appear with unclear boundaries. Our first two cases were consistent with these reports, in terms of image findings, although more cases should be accumulated to draw conclusions.…”

“…Most of these tumors are metastasized from the contralateral breast cancer, indicating cases metastasized from extramammary malignant tumors are even rarer. Metastasis to the breast might occur via both lymphatic and hematogenous [ 2 , 3 ], but in any case, breast is the organ which is unlikely to metastasize. As primary tumors metastasizing to the breast, malignant melanoma, lung, ovarian, renal, and thyroid cancers are reportedly known [ 4 ].…”

Breast Metastasis of Gastric Signet Ring Cell Carcinoma: A Case Report and Literature Review

“…The mass is usually round, well defined, and in some cases presenting with calcifications. It may also resemble a benign breast lesion [13, 23, 24]. Ultrasound results including skin thickening and breast nodules, indistinguishable from those of primary breast cancer, were unassociated with overall survival time ( p > 0.05), which suggests that it is difficult to diagnose metastatic breast cancer by clinical presentation or diagnostic imaging [1].…”

“…The most reported stains show positivity for carcinoembryonic antigen, CK7, and CK20, and the absence of markers such as hormone receptors and GCDFP15 (gross cystic disease fluid protein-15) [1, 12, 14]. Nevertheless, cytokeratins alone are not sufficient to make the differential diagnosis of primary metastatic tumors [11, 23-28], while special stains particularly for hormonal receptors (estrogen and progestin receptors) and GCDFP15 are considered specific for metastatic breast carcinomas [11, 24]. The presence of signet ring cells in a breast specimen forces one to rule out a primary gastric tumor as the origin [10], although the possibility of a primary breast tumor with signet ring cells is possible [21].…”