Breast implant-associated squamous cell carcinoma (BIA-SCC): Clinicopathologic analysis of two cases with radiologic-pathologic correlation and a review of the literature.

Breast implant-associated squamous cell carcinoma (BIA-SCC) is an exceptionally rare and poorly characterized malignancy that arises from the fibrous capsule surrounding breast implants. Due to its rarity, the clinicopathologic features and optimal diagnostic strategies remain incompletely defined. This report presents two cases of BIA-SCC, correlating clinical, radiologic, cytologic, pathologic, and outcome findings with the existing literature. Both patients presented in their 50s, one to two decades after initial silicone breast implantation, exhibiting breast pain and swelling. Although both initially received silicone implants, implant exchange procedures had occurred during the intervening years. Imaging revealed a peri-implant fluid collection (seroma) with/without parenchymal breast mass. In one case, cytologic analysis of seroma fluid identified squamous cells, a finding consistent with previous reports and supporting the utility of aspiration cytology for triaging suspicious peri-implant lesions. Clinical outcomes varied significantly: one patient developed locally aggressive disease with multiple recurrences within months, necessitating adjuvant radiation therapy and chemotherapy, while the second patient remains free of locoregional recurrence following standard-of-care complete capsulectomy. Given the potentially aggressive behavior of BIA-SCC, in cases of late-onset peri-implant seroma or capsular mass, the presence of squamous cells on aspirate cytology may facilitate early recognition. However, definitive diagnosis requires clinicoradiologic correlation and histopathologic confirmation of invasive squamous cell carcinoma originating from the breast capsule. Increased awareness of BIA-SCC may enable earlier diagnosis and appropriate multidisciplinary management.