Myofibroblastoma Arising in Mammary Hamartoma: A Case Report

Abstract

Myofibroblastoma (MFB) is a rare mesenchymal tumor arising in breast's soft tissue with a great variety of microscopic features that can be mistaken with a wide variety of biphasic lesions. The authors report a rare case of myofibroblastoma of the breast arising in a mammary hamartoma (MH), present a review of the clinicopathological features of these lesions, and make some diagnostic considerations. The tumour consisted of a well-circumscribed nodule. MFB component comprised about fifty percent of the lesion and was made up of bipolar spindle cells arranged in fascicular clusters separated by bands of hyalinized collagen. There were fat cells and several residual hamartoma glands intermingled and distorted in MFB area. MFB component was positive for Desmin, CD34, bcl-2, and Calponin. To the best of our knowledge, MFB has not been reported in MH, neither has any of the reports described mammary glands joined within MFB.

Male Breast Cellular Myofibroblastoma With a Rich Reticulinic Network

“…All the reported cases revealed a characteristic expression of vimentin, CD34, and desmin (Desrosiers et al, 2007;Lee et al, 2010;Sagar et al, 2011;Uchôa et al, 2010). Some tumor cells expressed SMA and calponin, and caldesmon is present in 50% of the cases reported (Magro et al, 2003).…”

“…Association of cartilaginous or smooth muscle areas and giant cells components were also reported (Miller, Levine, & Simmons, 1997). Sometimes, myofibroblastoma may arise in a mammary hamartoma and may present interspersed epithelial structures, which may increase the difficulty of diagnosis (Uchôa et al, 2010). Also described were cases with infiltrating patterns and calcifications seen on mammography (Kobayashi et al, 1996) or collision tumors (Wei & Zhu, 2011), which may lead to an incorrect diagnosis.…”

“…Some tumor cells expressed SMA and calponin, and caldesmon is present in 50% of the cases reported (Magro et al, 2003). At the same time, they are negative for cytokeratin, factor VIII-related antigen, and S-100 protein (Lee et al, 2010;Uchôa et al, 2010) and may be negative or positive for bcl-2 (Desrosiers et al, 2007;Uchôa et al, 2010). Although in most of the cases tumor cells are negative for CD10 and CD99 (Uchôa et al, 2010), in some cases they can be positive (Magro, Caltabiano, Di Cataldo, & Puzzo, 2007;Tavassoli & Soares, 2003).…”

“…At the same time, they are negative for cytokeratin, factor VIII-related antigen, and S-100 protein (Lee et al, 2010;Uchôa et al, 2010) and may be negative or positive for bcl-2 (Desrosiers et al, 2007;Uchôa et al, 2010). Although in most of the cases tumor cells are negative for CD10 and CD99 (Uchôa et al, 2010), in some cases they can be positive (Magro, Caltabiano, Di Cataldo, & Puzzo, 2007;Tavassoli & Soares, 2003). Sometimes, myofibroblastoma may express androgen, estrogen, or progesterone receptors (Desrosiers et al, 2007;Magro et al, 2007) and may associate gynecomastia, as in our case.…”

Masq U Erading Mammary Hamartomas

“…However invasive ductal carcinoma and myofibroblastoma are some tumors known to arise from mammary hamartomas. [15,16,17] CONCLUSION: Due to nonspecific diagnostic histological features, the diagnosis of hamartoma is challenging. Macroscopic examination of lumpectomy specimens should be performed with caution.…”