Background: PET2-adapted approach after 2 cycles of ABVD reduced treatment intensity in the majority of patients with early stages of classical Hodgkin lymphoma (cHL) according to EORTC H10 trial. GHSG HD17 enabled omission of radiotherapy in PET4-negative early unfavorable HL treated with 2 cycles of BEACOPP escalated and 2 cycles of ABVD (2+2 chemotherapy). We compared PET2-adapted approach with 2+2 chemotherapy followed by 30 Gy of involved-node radiotherapy (INRT) regardless of interim PET in patients with early unfavorable cHL assessed according to the GHSG risk factors.
Methods: Overall, 224 patients with early unfavorable cHL (aged 18-60 years) prospectively observed in the Czech Hodgkin Lymphoma Study Group Registry between 2003-2021 were analyzed. Patients in clinical stage IIB with massive mediastinal tumor and/or with extranodal disease were excluded. Overall, 194 patients received 2+2+INRT chemotherapy and 30 patients were treated with PET2-adapted approach: 29 PET2-negative patients received 4 cycles of ABVD and 30 Gy of INRT and one PET2-positive patient was treated with 2 cycles of ABVD plus 2 cycles of BEACOPP escalated and 30 Gy INRT.
Results: Median age at the time of cHL diagnosis was 32 (range 18-59) years. Median follow-up was longer in the 2+2+INRT group (98.9, range 6.2-211.7) months compared to the PET2-adapted approach (30.8, range 9.8-90.4) months. The 2-year progression-free survival and 2-year overall survival did not differ between two groups (99.5% [95% CI 98.5%-100%]) and 100% [95% CI 100%-100%]), respectively. The rate of patients with neutropenia grade 3 and anemia grade 3 did not differ significantly between both groups (p=0.09 and p=0.60, respectively). Thrombocytopenia was more frequent in the 2+2+INRT group (p0.001). Grade 3 non-hematological toxicity occurred in 3 patients in the 2+2+INRT group (2 infections, 1 deep vein thrombosis).
Conclusion: This retrospective analysis indicates that there is no superiority in progression-free survival and overall survival when comparing 2+2 chemotherapy and INRT to PET2-adapted approach. The toxicity is higher in the 2+2+INRT group.
This work was supported by the following grants: AZV NU22-03-00182 from the Ministry of Health of the Czech Republic and Cooperatio Program awarded by the Charles University in Prague in the Czech Republic.