Positron Emission Tomography-Based Assessment of Metabolic Tumor Volume Predicts Survival after Autologous Hematopoietic Cell Transplantation for Hodgkin Lymphoma

Autologous hematopoietic cell transplantation (AHCT) is curative for 60% of patients with relapsed or refractory Hodgkin lymphoma (R/R HL). A more precise assessment of the depth of remission before AHCT may help to identify patients likely to benefit from AHCT. We aimed to determine whether positron emission tomography (PET)-based quantitative parameters of total metabolic tumor volume (TMTV), total lesion glycolysis (TLG), and maximal standardized uptake volume (SUVmax) measured before AHCT predict progression-free survival (PFS) after transplant. Pretransplant PET/computed tomography images of 96 consecutive patients with R/R HL were analyzed. Median TMTV, TLG, and SUVmax were 7.97 cm3 (range, 1.3 to 102.1), 23.7 (range, 4.0 to 813.1), and 5.23 (range, 2.7 to 23.2). Two-year PFS in patients with high TMTV (TMTVhigh; more than median; n = 17) was only 12% (95% CI, 1% to 38%) compared with 53% (95% CI, 28% to 73%; P = .05) in patients with TMTVlow (lower or equal to median; n = 17) and 63% (95% CI, 50% to 74%) in 61 patients with no metabolically active tumor (TMTV0; P > .01). In concordance, high TLG (>19) and SUVmax (>4.9) predicted inferior 2-year PFS. In multivariate analysis patients with TMTVhigh had a 3.5-fold higher risk of treatment failure compared with TMTV0/TMTVlow (HR, 3.49; 95% CI, 1.75 to 6.93; P < .01). Deauville (D)-scores of 4 to 5 before AHCT predicted worse PFS compared with D-scores of 1 to 3 (HR, 3.7; 95% CI, 1.92 to 7.28; P < .01). Yet, TMTV and D-scores were disconcordant in 12 subjects; 9 patients in the D4 group with TMTVlow had 2-year PFS of 44% (95% CI, 14% to 72%), which was 2-fold higher than predicted by D4 score. In conclusion, in patients with R/R HL and PET-positive residual disease, TMTVhigh can identify very poor AHCT responders. Patients with TMTVlow, TLG, and SUVmax before AHCT have similar outcomes to those without metabolically active disease.