Early progression and transformation of a splenic diffuse red pulp small B-cell lymphoma with NOTCH1, ARID2, CREBBP, and TNFRSF14 gene mutations.

Splenic diffuse red pulp small B-cell lymphoma (SDRPL) is a rare entity. Diagnosis is typically achieved with splenectomy and most patients remain in remission after this intervention. Hemoglobin value less than 10 g/dL and NOTCH1, TP53, and MAP2K1 gene mutations at diagnosis have been associated with worse outcome. Progression after splenectomy of SDRPL is possible, although transformation to aggressive lymphoma has rarely been reported. We herein report the case of a patient formerly diagnosed with SDRPL with gene mutations involving CREBBP, NOTCH1, ARID2, and TNFRSF14 who transformed to diffuse large B-cell lymphoma six months after splenectomy.