Abstract: PURPOSE: To discuss the diagnosis and prognosis of progressively transformed germinal center and emphasize the necessity of long term follow-up after treatment. METHODS: Three patients were diagnosed as progressively transformed germinal center (PTGC) from 2010 to 2012. The clinical characteristics, histological features, differential diagnosis, prognosis were analyzed with review of literatures. RESULTS: Among 3 cases, 2 were found around parotid gland, one was in the neck. All patients were young male adults, who received excisional biopsy and regular histopathological examination. They were followed up for 8 months to 2.5 years, no relapse was found. CONCLUSIONS: PTGC occurs more commonly in young male adults. It always appears as an isolated and painless enlarged lymph node, which responses poorly to antibiotics. The final diagnosis is relied on histopathological and immunocytochemical examinations. Close follow-up is necessary, and attention should be paid to nodular lymphocyte predominant Hodgkin’s disease although there is no clear evidence about their relationship of development.

Key words: Progressively transformed germinal center, Reactive follicular hyperplasia, Nodular lymphocyte predominant Hodgkin’s disease, Follicular lymphoma