A multi-institutional and case-matched control study on treatment outcomes of consolidative radiotherapy after a full course of R-CHOP compared with R-CHOP alone in Stage I–II diffuse large B-cell lymphoma (KROG 17-02)

• Published in: Journal of radiation research 2019-10, Vol.60 (5), p.677-684
• Main Authors: Chung, Mi Joo, Cho, Won Kyung, Oh, Dongryul, Eom, Keun-Yong, Kim, Jin Hee, Kim, Woo Chul, Lee, Jong Hoon
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Cancer; Care and treatment; Case-Control Studies; Chemotherapy; Cyclophosphamide - therapeutic use; Development and progression; Disease-Free Survival; Doxorubicin - therapeutic use; Humans; Lymphoma, Large B-Cell, Diffuse - drug therapy; Lymphoma, Large B-Cell, Diffuse - pathology; Lymphoma, Large B-Cell, Diffuse - radiotherapy; Lymphomas; Methods; Middle Aged; Multivariate Analysis; Neoplasm Staging; Patient outcomes; Prednisone - therapeutic use; Radiotherapy; Regular Papers; Rituximab - therapeutic use; Treatment Outcome; Vincristine - therapeutic use; Young Adult
• ISSN: 0449-3060; 1349-9157
• DOI: 10.1093/jrr/rrz043

Abstract We compared treatment outcomes between rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy alone with R-CHOP followed by consolidative radiation therapy (RT) in diffuse large B-cell lymphoma (DLBCL). We analyzed 404 patients with Stage I–II DLBCL who received six to eight cycles of R-CHOP and achieved a good response after a full course of chemotherapy. Propensity-score matching was used to assess the role of consolidative RT. The R-CHOP alone group (n = 184) was matched in a 1:2 ratio with the R-CHOP plus RT group (n = 92). Twenty-four (13.0%) of 184 patients receiving R-CHOP alone and 8 (8.7%) of 92 patients receiving R-CHOP plus RT had bulky diseases (>7.5 cm). A Deauville score of 1–2 was achieved for 159 (86.4%) of 184 patients receiving R-CHOP alone and 84 (91.3%) of 92 patients receiving R-CHOP plus RT. After a median follow-up time of 42 months, the recurrence-free survival (RFS) rate (86.7% vs 93.0%, P = 0.464) and overall survival rate (88.3% vs 95.1%, P = 0.295) at 5 years did not differ significantly between the R-CHOP alone and R-CHOP plus RT arms. In the additional multivariate analyses, large tumor size (>7.5 cm) was significantly associated with decreased RFS (hazard ratio, 2.368 and confidence interval, 1.837–6.697; P = 0.048). Consolidative radiation was not a significant factor for RFS (P = 0.563). Tumor size was a significant factor for RFS in the rituximab era. The outcome of omitting consolidative RT for good responders after six to eight cycles of R-CHOP chemotherapy was acceptable in early-stage DLBCL without a bulky disease.