Where Does Diffuse Large B-Cell Lymphoma Relapse?

This study aimed to investigate the anatomic pattern of disease spread at first disease relapse compared with baseline in diffuse large B-cell lymphoma (DLBCL).

All patients who were newly diagnosed as having DLBCL between January 2004 and June 2014 who initially achieved complete remission but who eventually developed relapsed disease during follow-up were retrospectively identified. Available histological and imaging data were used to determine which nodal regions and extranodal locations were involved at relapse.

A total of 21 patients with relapsed DLBCL were included, of whom 8 (38.1%) presented with disease relapse at previously involved sites only, 7 (33.3%) presented with disease relapse at both previously involved and new sites, and 6 (28.6%) presented with disease relapse at new sites only. A total of 57 nodal stations and 34 extranodal locations were involved in all 21 relapsed DLBCL patients. Of these 57 involved nodal regions, 47 (82.5%) were also involved at baseline, whereas 10 (17.5%) were not involved at baseline. Of the 34 involved extranodal locations, 17 (50.0%) were also involved at baseline, whereas 17 (50.0%) were not involved at baseline.

Relapsed DLBCL generally tends to affect previously involved sites, although close to one third of patients seem to have disease recurrence exclusively in previously uninvolved sites. The great majority of involved nodal stations at relapse are also involved at baseline, whereas only one half of involved extranodal locations at relapse are involved at baseline.