The rectum and appendix are the two major sites of well-differentiated endocrine neoplasms (carcinoid tumors) in the lower gastrointestinal tract. Previously, we reported the consistent expression of peripherin in rectal well-differentiated endocrine neoplasms without metastases. However, its expression has not as yet been examined in appendiceal well-differentiated endocrine neoplasms. The aim...

Appendiceal neoplasms include a heterogeneous group of epithelial and nonepithelial tumors that exhibit varying malignant potential. This review article summarizes current diagnostic criteria, classification systems, optimal therapeutic strategies for the five main histopathologic subtypes appendiceal neoplasms. In particular, management has evolved. Although their treatment historically been e...

Mucinous neoplasms of the appendix are a heterogeneous group of neoplasms ranging from simple mucoceles to complex pseudomyxoma peritonei. Considerable controversy exists on their pathologic classification and nomenclature. Clear understanding of the histopathologic diversity of these neoplasms helps in establishing proper communication between the radiologist, the pathologist and the surgeon. ...

Mucinous lesions of the appendix and ovary are commonly encountered in routine practice. There are several published classification schemes for appendiceal mucinous neoplasms with resultant inconsistent use of terms and clinical doubt. While nomenclature is more settled with regards to ovarian mucinous neoplasms, the difficulty here lies with distinguishing primary from secondary mucinous tumou...

Heterotopic bone formation is a very rare event in the gastrointestinal tract including in the appendix. Here we report three cases of heterotopic ossification in appendiceal mucinous neoplasms, one occurring in an appendiceal mucinous cystadenoma, another in a low-grade appendiceal mucinous neoplasm, and the third occurring in an appendiceal mucinous adenocarcinoma. The clinicopathologic chara...

To cite: Rouzbahman M, Chetty R. J Clin Pathol 2014;67:193–197. ABSTRACT Mucinous lesions of the appendix and ovary are commonly encountered in routine practice. There are several published classification schemes for appendiceal mucinous neoplasms with resultant inconsistent use of terms and clinical doubt. While nomenclature is more settled with regards to ovarian mucinous neoplasms, the diffi...

background: diseases and tumors of the appendix vermiformis are very rare, except acute appendicitis. objectives: this retrospective study was conducted to document the unusual findings in appendectomy specimens. patients and methods: data of 1466 adult patients were gathered retrospectively. appendectomy was performed in 1169 and in 297 patients following a diagnosis of acute appendicitis and ...

Appendiceal tumors are rare, late diagnosed neoplasms that may not be differentiated from adnexal masses even by advanced imaging methods and other diagnostic procedures. They may be asymptomatic and remain undiagnosed until surgery. We report a case of an 80-year-old postmenopausal woman presenting with a pelvic mass and a history of weight loss. The patient underwent laparotomy which revealed...

We report the case of a patient with appendiceal adenocarcinoma with mucinous peritoneal carcinomatosis who was treated with trametinib upon identification of a GNAS R201H mutation by comprehensive genomic profiling. The molecular pathology of appendiceal neoplasms is reviewed, and the mechanistic basis underlying the clinical benefit as well as the subsequent course on trametinib that were obs...