Pediatric follicular lymphoma in Japan.

Follicular lymphoma (FL) is quite rare in children. There have been only two major reports on pediatric FL. The present retrospective study on pediatric FL in Japan, including FL with diffuse large B cell lymphoma (DLBCL), analyzed data from 1991 to 2014. Twenty-two patients with pediatric FL were analyzed. Sixteen patients were boys and six were girls. Median age of onset was 9 years (range 4-17 years). In 11 patients, DLBCL co-existed with FL. The initial lesions involved cervical lesions in 16 patients, and the abdomen in six. With regard to stage of disease at diagnosis, 17 patients were at stage I or II, four were at stage III, and one was at stage IV. Chemotherapy was administered in 18 patients, and only resection was performed in four patients. Mature B lymphoma regimens were selected for 17 patients who received chemotherapy. Although two patients relapsed, all patients are currently alive and disease free. The median follow-up period was 54.5 months (range 6-126 months). Patients having FL with DLBCL were younger compared with those having FL, and this disease was more frequently observed in female patients. Our data revealed that FL in Japanese children is a tumor with good prognosis, as in reports from the United States and Europe.