Plasmablastic Lymphoma Presenting With Rectosigmoid Perforation in a Human Immunodeficiency Virus-Positive Patient

Abstract

Plasmablastic lymphoma (PBL) is a rare variant of diffuse large B-cell lymphoma (DLBCL) associated with human immunodeficiency virus (HIV)-positive patients. It accounts for only 2% of all acquired immune deficiency syndrome (AIDS)-related lymphomas (ARLs). We present the case of a 45-year-old male who presented to the emergency department (ED) with a three-month history of abdominal pain, diarrhea, and unintentional 50-lb weight loss. On an earlier presentation to the ED three months prior, the patient was diagnosed with norovirus and Helicobacter pylori infection and received outpatient treatment without resolution of his symptoms. This prompted further investigation with a CT of the abdomen and pelvis with IV contrast that revealed severe sigmoid colitis with pneumoperitoneum and a pericolonic air-containing fluid collection, consistent with a contained perforation with abscess formation. He was admitted, resuscitated, and initially treated with antibiotics and parenteral nutrition. The patient underwent a laparoscopic converted to open anterior resection with end colostomy. Pathology revealed HIV-related PBL. He was subsequently treated with dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab (DA-EPOCH-R) chemotherapy regimen and an autologous stem cell transplant. Despite its rare association with HIV, PBL should be considered a differential diagnosis for HIV-positive patients who present with gastrointestinal (GI) pathology, and additional investigations should be conducted if symptoms do not resolve despite appropriate medical management at the time.

Keywords: hiv; open anterior resection; perforation; plasmablastic lymphoma; stem cell transplant.

Figure 1. (A) Severe wall thickening and pericolonic inflammatory changes in the sigmoid colon (arrow). (B) Pericolonic extraluminal air and fluid (arrow). (C) Air-containing fluid collection, consistent with contained perforation with abscess formation (arrow).

Figure 2. (A) Focus of high FDG avidity adjacent to the left common iliac artery, suspicious for metastatic disease (arrow). (B) Focus of high FDG avidity within the rectum, suspicious for malignancy (arrow).

Figure 3. Sigmoid and proximal rectum segmentectomy. (A) A tan-brown thickened colonic mucosa with a transmural perforation site. (B) Cross section of the sigmoid colon revealing a soft, pink, hemorrhagic area below the thickened mucosa with diffuse fibrosis of the colonic wall.

Figure 4. Immunohistochemical phenotype. (A) High magnification of hematoxylin and eosin (H&E) staining of the atypical lymphoid infiltrates demonstrating immunopositivity for (B) CD79a and (C) MUM-1. (D) In situ hybridization demonstrating EBER RNA expression. The atypical lymphoid infiltrates also demonstrate (E) >90% proliferation index by Ki67 immunostaining and (F) lack of immunoreactivity to CD138.