First Reported Case of Extramedullary Plasmacytoma of the Appendix

Abstract

An extramedullary plasmacytoma involving the gastrointestinal tract is extremely rare. We report an appendiceal extramedullary plasmacytoma in a 35-year-old man who presented to the emergency department because of upper abdominal pain. Computed tomography (CT) imaging revealed an incidental mass (3.7 × 1.9 × 1.6 cm) at the tip of the appendix. Microscopically, the appendix, periappendiceal soft tissue, and nearby lymph nodes were diffusely infiltrated by plasma cells that were kappa light chain restricted. Subsequent workup included an unremarkable bone marrow biopsy, as well as urine and serum electrophoresis. A diagnosis of kappa-restricted solitary extramedullary plasmacytoma was made. To our knowledge, this is the first case reported of an appendiceal extramedullary plasmacytoma in the medical literature.

Acute Gangrenous Appendicitis in A 70-Year-Old Patient with Multiple Myeloma

“…It is worth noting that another phenomenon is observed in the rest of the appendiceal tumors, where a further decision is made, following the histopathological results and imagistic findings. However, plasmacytoma, as well as, the rest of the appendiceal tumors present the same clinical image on patients, this of a right lower quadrant pain, and even with the clinical mage of acute appendicitis [14,15].…”

“…Thinking about the imaging part and the finding, we notice that computed tomography the plasmacytes, appear as soft tissue tumors [14,15], while in the necrotic enterocolitis or cecitis, the point findings are the distention of the intestine with mucosal lesion and the increased wall thickness [7]. Likewise, the appendix in the case of patients with neutropenia, appears enlarged with increased thickness of the wall accompanied by mucosal damage [10].…”

“…Taking this into consideration, the decision for surgical invasion will be based on the clinical appearence, as well as, the imaging finding (free intraperitoneal air, intraperitoneal fluid diffusion, inflammation of the cecal base) [7]. Furthermore, it is essential to mention that in multiple myeloma the physician-surgeon, must take into consideration the possibility of extramedullary localization of the disease, even if, according to the data the gastrointestinal occurrence is rare, especially in the appendix [14,15]. The extramedullary localization of the disease constitutes approximately 3% of the entire plasmacyte's neoplasias category [16].…”

“…Of those 80% are tumors observed on the head and neck and only 5% are composed of gastrointestinal solid tumors as extramedullary localization [17] [18]. Talking about localization, it is impoortant to mention some of the most extremely rare anatomical areas of identification, the large intestine, as well as, the rectum, especially the iileocecal area [19,20] and the appendix [15].…”