Rare Mucinous Adenocarcinoma of the Appendix Undergoing Multiple Recurrent Surgical Interventions.

Primary appendiceal carcinomas are rare and often found incidentally when the appendix is surgically removed. Adenocarcinoma predominates the histological types of malignancies, with mucinous adenocarcinoma being the most prevalent of the various subtypes. Pseudomyxoma peritonei (PMP), a complication seen in mucinous adenocarcinoma of the appendix (MAA), is the collection of mucinous ascites in the intra-abdominal cavity and the thickening of the surrounding viscera by mucin-producing tumor cells. PMP initially presents with increased abdominal discomfort and girth and, in later stages, presents with obstructive abdomen symptoms. These symptoms are nonspecific and can be a challenge to pinpoint. Such was the case for our patient, in this case report, who initially presented with dyspepsia and later demonstrated compressive symptoms and weight loss, raising concern for malignancy. An appendiceal pathology was of concern when his right lower quadrant pain acutely worsened during an abdominal ultrasound, and imaging and biopsy confirmed MAA with PMP. The aim of this report is to shed light on the management of recurrent MAA. Our patient's recurrent MAA was managed with debulking procedures and three rounds of hyperthermic intraperitoneal chemotherapy (HIPEC) and was managed postoperatively with folinic acid, fluorouracil, and irinotecan (FOLFIRI) and bevacizumab, which in its totality helped achieve a progression-free survival of more than two years. We believe that cytoreduction and intraoperative chemotherapy prolong survival in patients with recurrent disease, as was the case with our patients. Our patient also demonstrated benefit as his disease stabilized after starting bevacizumab; however, more studies need to be performed at a larger scale to show a consistent relationship.

The Role of Avapritinib for the Treatment of Systemic Mastocytosis.

Systemic mastocytosis is a rare hematologic disorder characterized by the clonal proliferation of mast cells in extra-cutaneous organs. This disease can be further subdivided into five different phenotypes: indolent systemic mastocytosis (ISM), smoldering systemic mastocytosis (SSM), aggressive systemic mastocytosis (ASM), systemic mastocytosis with an associated hematological neoplasm (SM-AHN) and mast cell leukemia (MCL). The tyrosine kinase inhibitor (and also potent KIT D816V inhibitor) avapritinib, initially approved for the treatment of gastrointestinal stromal tumors (GISTs) bearing a PDGFRA exon 18 mutation, also showed great promise in patients with systemic mastocytosis, a disease known to be driven by a mutation in KIT (D816V). We present an overview of this rare disorder, including a review of the current understanding of the genetic mechanisms which lead to the disease state, the action of the tyrosine kinase inhibitors, as well as the latest clinical trial data which led to the current recommendations for the use of avapritinib.