Spontaneous Regression Of High-grade B-cell Lymphoma With Myc And Bcl2 Rearrangements: Case Report And Literature Review

Abstract

Background High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements is an aggressive lymphoma, mostly occurring in elderly patients, that frequently has poor response to therapy. We report a unique case of MYC/BCL2 double-hit lymphoma (DHL) in a 35-year-old male that spontaneously regressed without therapy. Methods Biopsy specimen was evaluated morphologically, by immunohistochemistry, fluorescence in situ hybridization (FISH), and next generation sequencing (NGS). Spontaneous regression was assessed with sequential positron emission tomography (PET)/computed tomography (CT) scans. Results Morphologically, lymphoma cells showed a diffuse, “starry-sky” pattern and were intermediate-sized with finely dispersed chromatin and several nucleoli. By immunohistochemistry, they were positive for CD20, CD10, BCL6, BCL2, C-MYC (60-70%), and Ki67 (80%). FISH study showed MYC and IGH/BCL2 rearrangements. NGS showed mutations of MYC, BCL2, and KMT2D, among others, in keeping with mutational profile of MYC/BCL2 DHL. PET/CT scans, performed at diagnosis, as well as 1 month and 7 months after diagnosis, demonstrated complete spontaneous regression of this lymphoma. Patient remains in remission 28 months after diagnosis. Conclusions Spontaneous regression of a higher grade B-cell lymphoma is a rare occurrence, and the reasons for it are unclear. Our case is a first documented MYC/BCL2 DHL that spontaneously regressed without therapy.