Development of follicular lymphoma after treatment of diffuse large B-cell lymphoma: two case reports with review of literature.

Diffuse large B-cell lymphoma (DLBCL) is one of the most frequent subtypes of aggressive lymphomas, which can be transformed lymphoma that mostly develops from other types of lymphoma. Cases of DLBCL arising developing after the initial diagnosis of follicular lymphoma (FL) have been reported. However, until now, little few studies have been reported were conducted on the patients with DLBCL and with subsequent development of FL in patients with DLBCL. Here we presented this study with two rare cases of, namely, FL and Composite concurrently occurs with DLBCL and FL developing after the initial diagnosis of DLBCL. In order to investigate the clinical and molecular features of patients with DLBCL and FL, we also reviewed the literature on FL patients with FL developing DLBCL, and patients with composite FL and DLBCL.