Case Reports in Pathology最新文献

Mammary Paget's disease (MPD) is a rare histological condition, accounting for 1-4% of female breast cancers, which may appear either independently (1.4-13% of the cases), or in association with an in situ or invasive ductal carcinoma (approximately 90% of the cases). The purpose of this article is to highlight the histopathological challenges related to the microscopical polymorphism of this disease and the utmost importance of immunohistochemistry in the thorough process of Paget's disease differential diagnosis. Moreover, the primary objective of this review of literature was to corroborate the existing data concerning the potential peculiar immunohistochemical profile that mammary Paget's disease might express. We report the case of a 44-year-old female patient, histopathologically diagnosed with HER2-negative MPD accompanying an invasive mammary carcinoma. The histopathological and immunohistochemical approach is derived from the exigency of excluding the possibility of synchronous tumors-a mammary invasive carcinoma, accompanied by another component with MPD phenotypic mimicry. The unexpected negative HER2 reaction is conducted to a primary focus on excluding a malignant melanoma in situ. The absence of MelanA and S100 immunoexpression and lack of pigmentation and clinical aspects infirmed it. Bowen's disease was invalidated by its rare presentation in the breast cutaneous tissue and the absence of individual risk factors suggestive of an existing immunosuppressive status. In the case of similar morphoimmunohistochemical aspects, significant expression of Ki-67 signals MPD, an immunoreactivity that helped distinguish the cellular population from Toker cells. The great similarity of MPD with other benign and malignant cutaneous tumors might determine delay or misdiagnosis. Thus, the utmost importance of immunohistochemistry is reflected in its prognostic significance and geared towards extending the therapeutic arsenal.

Granular cell tumor (GCT) is a benign neuroectodermal tumor typically in the dermis or subcutis, although deep soft tissues and organs are occasionally involved. Multifocal GCTs are estimated to occur as many as 10% of patients. A 40-year-old female presented with multiple GCTs asynchronously involving various body sites including gastrointestinal, gynecologic, breast, urinary, and soft tissue systems. Pathologic examinations suggested benign GCTs. TruSight Tumor 170 next-generation sequencing (NGS) analysis performed on four resected tumors revealed subclonal mutation of PIK3CA p.H1047R identified in the esophageal GCT but not in the right vulva or the two cecal GCTs, suggesting that each is a primary tumor with a distinct genetic profile, rather than metastasis. PIK3CA p.H1047R is a common mutation in many cancers. Our benign GCT case demonstrates PIK3CA mutation with a low mutant allele frequency of 7%, which may represent an evolving subclone and might confer a more aggressive behavior.

Tailgut cysts are congenital cysts arising in the retrorectal space. They are thought to be benign with variable malignancy risks. We report a case with previous surgical intervention decades prior that had undergone a tailgut cyst excision with surgical complications leading to carcinomatosis. An elderly female (70s) presented with tailbone/pelvic pain. She underwent cyst excision that was complicated by an intraoperative rupture. The cyst was pathologically proven to be a tailgut cyst with adenocarcinoma. She presented 13 months postoperatively to the emergency department with worsening abdominal pain. Imaging was concerning for diffuse omental nodules and narrowing of the proximal sigmoid colon. She was not deemed to be a surgical candidate and was transitioned to hospice care, where she passed away shortly afterward. This case report highlights the utility of complete excision of tailgut cysts and possible complications.