Clinical Characteristics and Prognosis of 56 Lymphoma Patients with Mediastinal Masses

OBJECTIVE: To analyze the incidence, clinical characteristics, treatment efficacy and prognosis of lymphoma patients with mediastinal masses. METHODS: The clinical data of 56 lymphoma patients with mediastinal masses treated in our hospital from February 2007 to January 2018 were collected, and the clinical characteristics, typing, staging, treatment efficacy as well as prognosis analyzed retrospectively. RESULTS: Among the 56 patients, male and female were 25 (45%) cases and 31(55%) cases, respectively. The median age was 31 (17-72) years old, out of them 48 (86%) patients aged below 40 years old. According to pathological classification, 9 (16.1%) cases were diffuse large B cell lymphoma, not otherwise specified (DLBCL-NOS), 26(46.4%) cases were primary mediastinal large B cell lymphoma (PMBCL), 17 (30.4%) cases were classical Hodgkin's lymphoma (cHL), and 4 (7.1%) cases were primary mediastinal grey zone lymphoma (MGZL). All the patients were treated with chemotherapy or immuno-chemotherapy.The median follow-up time was 54.5(11-149) months. In cHL group, 10 cases received involved field radiotherapy (IFRT), 10 (58.8%) cases achieved complete remission (CR), 2 (11.8%) cases achieved partial remisson (PR), and 5 (29.4%) patients experienced progressive disease (PD) , 6 patients with relapsed/refractory disease received autologous hematopoietic stem cell transplantation (auto-HSCT), the 1, 2, and 5 year overall survival (OS) rates of cHL group were 94.1%, 88.2%, and 67.2%, respectively. In MGZL group, 3 cases combined with IFRT, 1 case with auto-HSCT, 2 (50%) cases achieved CR, 2 (50%) cases experienced PD, the 1, 2, 5 year OS rates of MGZL group were 66.7%, 66.7%, and 33.3%, respectively. In PMBCL group, 8 cases combined with IFRT, 7 cases with auto-HSCT, 22 (84.0%) cases achieved CR, 2 (8.0%) cases achieved PR, 1 (4.0%) case was stable disease (SD) and 1 (4.0%) case experienced PD, the 1, 2 year OS rates of PMBCL group were both 100%, and 5 year OS rate was 95.7%. In DLBCL-NOS group, 3 cases combined with IFRT, 2 cases with auto-HSCT, 4 (44.5%) cases achieved CR, 2 (22.2%) cases achieved PR, 1 (11.1%) case was stable disease (SD) and 2 (22.2%) cases experienced PD, the 1 year OS rate of DLBCL-NOS cohort was 100%, 2, and 5 year OS rates were both 77.8%. There was a significant difference of OS rate among these 4 group (P0.05). In intra-group comparison, OS rate in PMBCL group were significantly longer than both MGZL group (P0.01) and cHL group(P0.05), and showed no significant difference from DLBCL-NOS group (P0.05). CONCLUSION: Mediastinal masses are characterized by unique clinical features due to their unique anatomical location. Several B cell originated lymphomas including cHL,MGZL,PMBCL and DLBCL-NOS, manifested primary or secondary mediastina involvement, tend to occur in young adults and have similar clinical features. However, their therapeutic response was significantly different. The prognosis of PMBCL is prior to MGZL and cHL.