Breast neoplasm with distinct histological subtypes: A case report

Abstract

Introduction: Breast cancer is a heterogeneous disease, divided into many subtypes, the most common being invasive
ductal. Breast tumors can be derived from epithelial tissue or mesenchymal cells. Most malignant breast tumors are made
up of a single type of tumor. Cases where there are two or more types of malignant tumors occurring at the same time
are rare. We report a case with different types of malignancies, i.e., non-special invasive ductal carcinoma, metaplastic
carcinoma, and squamous cell carcinoma occurred together. Case report: A woman, 56 years old, with no family history of gynecological neoplasia, sought care referring to a painful and erythematous nodule in her left breast for about
25 days. On physical examination, a 15×11 cm, slightly mobile nodule with irregular borders was noticed in the left breast
and palpable axillary lymph nodes. The mammogram showed an isodense nodule with internal calcifications, measuring
10.2×9.4×7.2 cm, in the superolateral quadrant (QSL) of the left breast (ME) — BI-RADS V. The central biopsy showed nonspecial invasive breast carcinoma (NOS), triple-negative, and KI67 30%. She underwent neoadjuvant chemotherapy, and
5 months after the start, she showed evidence of tumor progression. The tumor was ulcerated and occupying the entire
QSL of ME and on palpation of the armpit, multiple hardened lymph nodes on the left. Left radical mastectomy with axillary lymphadenectomy was performed. The anatomopathological examination of the specific specimen revealed different
tumor types: ulcerated and moderately differentiated squamous cell carcinoma, invasive metaplastic breast carcinoma,
with a negative immunohistochemical profile for RP, ER, and HER2, positive cytokeratin 7, and 70% Ki67. Two months
after the mastectomy, she had tumor recurrence and underwent a new surgical approach. Plastron histopathology showed
squamous cell carcinoma infiltrating skin, negative estrogen and progesterone receptors, and positive p63. She underwent
radiotherapy and is currently being followed up, with no signs of recurrence.