Diffuse large B-cell lymphoma with perianal mass pain as the initial presentation: a case report and literature review

［Abstract］ Diffuse large B-cell lymphoma is an aggressive tumor originating from mature B cells, typically presenting as generalized lymphadenopathy. However, the occurrence of extranodal lymphoma in perianal soft tissue is exceedingly rare. Due to the lack of specific clinical manifestations and imaging modalities, its clinical diagnosis is difficult and misdiagnosis rate is high. This article reports the diagnosis and treatment of a case of diffuse large B-cell lymphoma with perianal mass pain as the first manifestation, and reviews the relevant in order to improve the clinician’s understanding of this condition, avoid misdiagnosis and missed diagnosis.