SIGNIFICANCE OF TUMOR SIZE AND RADIATION-DOSE TO LOCAL-CONTROL IN STAGE I-III DIFFUSE LARGE-CELL LYMPHOMA TREATED WITH CHOP-BLEO AND RADIATION

Purpose: The purpose of this study was to evaluate the possible effect of adjunctive involved field (IF) radiotherapy on long-term local con trol for patients with Ann Arbor Stage I-III diffuse large cell lympho ma (DLCL) who achieved a complete remission on a combined modality pro gram which included cyclophosphamide, doxorubicin, vincristine, predni sone, and Bleomycin (CHOP-Bleo). Methods and Materials: One hundred an d ninety patients with Ann Arbor Stage I-III DLCL were treated with CH OP-Bleo and radiotherapy. Analyses were undertaken to determine (a) re sponse to treatment according to stage, extent of maximum local diseas e, and irradiation dose either < 40 Gy or greater than or equal to 40 Gy and (b) relapse patterns. Results: A complete remission (CR) was ac hieved in 162 patients. Among patients who achieved a CR, local contro l was better for those who received tumor doses of greater than or equ al to 40 Gy (97%) than for those who received < 40 Gy (83%) (p = 0.002 .) Among those with extensive local disease, the corresponding control rates were 88% and 71%, respectively. A study of distant relapse patt erns following a CR showed that the first relapse usually involved an extranodal site. Conclusion: Radiotherapy was an effective adjunctive treatment to CHOP-Bleo for patients with stage I-III DLCL who achieved a CR. Patterns of relapse suggested that total nodal irradiation (TNI ) possibly could have benefited a small subset of patients.