Concurrent breast stroma sarcoma and breast carcinoma: a case report

Area of Science:

• Oncology
• Pathology

Background:

• Breast cancer is a significant global health concern affecting numerous women worldwide.
• Bilateral breast cancer, occurring in both breasts, is uncommon and typically involves tumors of the same histological type.
• Concurrent bilateral breast cancer with distinct histological types is exceptionally rare.

Purpose of the Study:

• To report a rare case of simultaneous bilateral breast cancer with two different histological types: invasive mammary carcinoma and breast sarcoma.
• To describe the diagnostic and treatment approach for this unique clinical presentation.

Main Methods:

• A 42-year-old woman presented with distinct breast nodules, diagnosed via biopsy as invasive mammary carcinoma (right breast) and sarcoma (left breast).
• The patient underwent bilateral modified radical mastectomy, followed by chemotherapy (5-fluorouracil, epirubicin, cyclophosphamide) and radiotherapy.
• Hormone receptor-positive invasive mammary carcinoma was treated with tamoxifen and subsequently letrozole.

Main Results:

• Histological examination confirmed invasive mammary carcinoma (grade II lobular pleomorphic type) with axillary lymph node involvement in the right breast.
• A mammary stroma sarcoma, negative for epithelial biomarkers and positive for vimentin, was identified in the left breast.
• The patient completed treatment with no signs of disease progression at the last follow-up.

Conclusions:

• The annual risk of bilateral breast cancer is approximately 1%, with a higher incidence in lobular histology.
• This case underscores the occurrence of simultaneous, histologically distinct bilateral breast tumors, representing a rare clinical scenario.