Not everything is as it seems: a rare form of metastatic breast cancer

Cutaneous metastasis of occult breast cancer: a case report

Occult breast cancer (OBC) is characterized by metastatic presentation of undetectable breast tumor on imaging exams. OBC is a rare disease (accounting for 0.3% to 1.0% of all breast cancers) that represents a major diagnostic challenge. The aim of this study was to report a case of OBC with primary presentation of multiple cutaneous metastases with subsequent emergence of bone metastasis. A 70-year female patient had multiple cutaneous metastatic lesions in the left cervical region, left breast, left axillary region, left subscapular region, in three chirodactylus of the right hand and three chirodactylus of the left hand. Imaging tests (mammogram, ultrasonography and magnetic resonance imaging of the breast) did not show alterations. Biopsy, histology sections and immunohistochemistry of the left cervical cutaneous lesion were compatible with OBC. After two years of anastrozole treatment (1mg/day), there was regression of all cutaneous lesions and stabilization of bone metastasis. OBC has a better prognosis. It may exhibit spontaneous regression or respond to less aggressive treatment strategies, as described in this case.

Adipose Tissue from Lean and Obese Mice Induces a Mesenchymal to Epithelial Transition-Like Effect in Triple Negative Breast Cancers Cells Grown in 3-Dimensional Culture

Breast cancer is the second leading cause of cancer-related mortality among women globally with obesity being one risk factor. Obese breast cancer patients have at least a 30% increased risk of death from breast cancer compared to non-obese breast cancer patients because they present with larger tumors and generally have increased rates of metastasis. Moreover, obese breast cancer patients respond more poorly to treatment compared to non-obese patients, particularly pre-menopausal women diagnosed with triple negative breast cancer (TNBC). To help understand the molecular mechanisms underlying the increased metastasis associated with obesity, we previously established a three-dimensional culture system that permits the co-culture of adipocytes and TNBC cells in a manner that mimics an in vivo milieu. Using this system, we demonstrate that white adipose tissue from both lean and obese mice can induce a partial mesenchymal-to-epithelial transition (MET). Triple negative breast cancer cells adopt an epithelial morphology and have an increased expression of some epithelial markers, but they maintain the expression of mesenchymal markers, furnishing the breast cancer cells with hybrid properties that are associated with more aggressive tumors. Thus, these data suggest that adipose tissue has the potential to promote secondary tumor formation in lean and obese women. Further work is needed to determine if targeting the partial MET induced by adipose tissue could reduce metastasis.