[Clinicopathological features of long-term tumor-free survival of patients with untreated primary tonsillar diffuse large B-cell lymphoma].

Objective To investigate the clinicopathological features of long-term tumor-free survival in patients with untreated primary diffuse large B-cell lymphoma (DLBCL) of the tonsil. Methods The study included 80 consultation cases of primary tonsillar DLBCL from April 2006 to July 2017 in the Department of Pathology, Beijing Friendship Hospital, Capital Medical University. The patients were divided into two groups: experimental groups of 10 untreated patients with long-term tumor-free survival, and 70 patients who had been treated (control group). The clinical data, histopathological features, immunohistochemical staining, and molecular biology test results of the patients were analyzed retrospectively. Results Patients who had long-term tumor-free survival with untreated primary diffuse large B-cell lymphoma had the disease mostly confined to the tonsil. Biopsy showed that the tonsil structure was only partially effaced and the lesions were relatively "fresh". EBER and FISH test for t (14;18) results were negative. Gene rearrangement detection showed monoclonality. There was statistically significant difference between the age, bcl-2 expression, CMYC protein expression and co-expression of CMYC and bcl-2 between the untreated group and the treated group(P 0.05); The median overall survival of the untreated group and treated group was 81 months and 20 months, respectively, and the difference was not statistically significant (P>0.05).In patients younger than 40 years of age, the untreated group had a statistically significant difference in primary site and CMYC protein expression compared with the treated group (P<0.05), and there was no statistical significance in other aspects. Conclusions Long-term tumor-free survival patients with untreated tonsillar primary DLBCL have relatively unique clinical characteristics. There is no significant difference in the prognosis between the untreated and treated groups, indicating radiotherapy and chemotherapy may not be required and therefore, avoiding related side effects. Key words: Tonsillar neoplasms; Lymphoma, large B-cell, diffuse; Pathology, clinical