Synchronous Bilateral In Situ Solid Papillary Carcinoma of the Breast: A Report of a Rare Case.

Solid papillary carcinoma is a rare breast neoplasm characterized by neuroendocrine differentiation, a circumscribed solid growth pattern, and delicate interspersed fibrovascular cores. It typically exhibits low to intermediate nuclear atypia and generally carries an excellent prognosis, even when invasion is present. Most cases are unilateral, with bilateral occurrences being exceptionally uncommon. Here, we describe a very rare case of bilateral in situ solid papillary carcinomas of the breast in a 67-year-old woman.