Metaplastic Carcinoma and Invasive Lobular Carcinoma of Breast: Rare Collision Tumor of Breast With Review of Recent Literature

摘要

Collision tumors are type of tumors where two histologically distinct type of tumors occur at thesame anatomic location. Breast collision tumors comprising carcinoma and lymphoma or invasive ductalcarcinoma with invasive lobular carcinoma are relatively common. However, a collision tumor betweenmetaplastic breast carcinoma (MBC) and invasive lobular carcinoma (ILC) is extremely rare. Here, we reporta case of collision tumor in breast comprising MBC and ILC. A 60-year-old female patient presented inoutdoor department with palpable painless firm mass in left breast. FNAC diagnosis of class V smears wasmade. Wide local excision was done and specimen sent for frozen section analysis. On frozen section,diagnosis of malignant neoplasm was made and suspicion of malignant phyllodes and MBC was raised. Allmargins were reported free as free of the tumor. Further sectioning revealed another tumor, 0.1 cm away frommain tumor. Sections from this tumor showed a malignant neoplasm arranged in cords with tumor cellshaving eccentric nuclei and moderate amount of cytoplasm. Immunohistochemical (IHC) analysis showedspindle cell tumor with profile favoring MBC while IHC analysis of second tumor was consistent with thediagnosis of ILC. Final diagnosis of collision tumor was made.