Synchronous primary diffuse large B Cell lymphoma and rectal adenocarcinoma: a case report

Abstract

Diffuse large B cell lymphoma (DLBCL) synchronous with rectal adenocarcinoma is extremely rare. We know of only a few cases reported in the literature. Multiple primary tumors are diagnostically and therapeutically challenging cases, as two malignant neoplasms are detected simultaneously. We describe the case of a patient with synchronous DLBCL and rectal adenocarcinoma. A 48-year-old male presented with hematochezia for 3 months with palpable lumps in the neck and axilla. The patient had previously been diagnosed with Non-Hodgkin lymphoma (NHL) and had completed 6 cycles of CHOP chemotherapy. Abdominal MRI and colonoscopy revealed a rectal mass, and histopathological examination confirmed adenocarcinoma. Biopsies of the cervical and axillary lymph nodes showed features consistent with DLBCL, confirmed from histopathology and immunohistochemistry. A multidisciplinary team conducted a comprehensive evaluation to determine the patient’s individualized treatment plan. The diagnosis of multiple primary cancers was based on the Warren and Gates criteria, which were met in this case as confirmed by histopathology, immunohistochemistry, and abdominal MRI. The patient was classified as stage III DLBCL and clinical stage IIIC rectal adenocarcinoma. There are not many reports of double malignancy cases such as this. DLBCL is an aggressive and rapidly progressive type of NHL, making it a priority for treatment. Once NHL is controlled or in partial remission, attention can be turned to the management of rectal adenocarcinoma. Patients with DLBCL and rectal adenocarcinoma highlight the importance of a multidisciplinary team approach and comprehensive evaluation to determine individual therapeutic strategies.