Post-ABVD/pre-radiotherapy (18)F-FDG-PET provides additional prognostic information for early-stage Hodgkin lymphoma: a retrospective analysis on 165 patients

Abstract

Objective: To evaluate the prognostic role of both interim fluorine-18 fludeoxyglucose positron emission tomography (i-(18)F-FDG-PET) and end-of-chemotherapy fluorine-18 fludeoxyglucose positron emission tomography (eoc-(18)F-FDG-PET) in patients with early-stage Hodgkin lymphoma (HL).

Methods: We screened 257 patients with early-stage HL treated with combined modality therapy between March 2003 and July 2011. All were staged using fluorine-18 fludeoxyglucose positron emission tomography ((18)F-FDG-PET) before chemotherapy and after two doxorubicin, bleomycin, vinblastine and dacarbazine cycles (i-(18)F-FDG-PET); 165 patients were also evaluated by (18)F-FDG-PET at the end of chemotherapy (eoc-(18)F-FDG-PET).

Results: After revision, 85% of patients were negative for i-(18)F-FDG-PET and 15% were positive. After eoc-(18)F-FDG-PET revision, 23 patients had a positive scan. The median follow-up was 56 months. The 5-year overall survival (OS) and progression-free survival (PFS) for the whole cohort were 97.5% and 95.6%, respectively. For i-(18)F-FDG-PET-negative and i-(18)F-FDG-PET-positive patients, the 5-year PFS rates were 98% and 84%, respectively; for eoc-(18)F-FDG-PET-negative and eoc-(18)F-FDG-PET-positive patients, the 5-year PFS rates were 97% and 78%, respectively. Combining the i-(18)F-FDG-PET and eoc-(18)F-FDG-PET results, the 5-year PFS were 97%, 100% and 82% in negative/negative, positive/negative and positive/positive groups, respectively. The 5-year OS rates were 98% and 83% in eoc-(18)F-FDG-PET-negative and eoc-(18)F-FDG-PET-positive patients, respectively; the 5-year OS was 98%, 100% and 83% in negative/negative, positive/negative and positive/positive groups, respectively.

Conclusion: This study provides additional information on the prognostic role of i-(18)F-FDG-PET and eoc-(18)F-FDG-PET in early-stage HL. As data are accumulating and the clinical scenario is rapidly evolving, we might need to rethink the use of (18)F-FDG-PET as a prognostic marker for early-stage HL in the near future.

Advances in knowledge: This study provides additional information on the prognostic role of i-(18)F-FDG-PET and eoc-(18)F-FDG-PET in early-stage HL. On the basis of the present data, we may suggest to use eoc-(18)F-FDG-PET as a strong prognostic marker, especially for patients with i-(18)F-FDG-PET positivity.

Figure 1.

Treatment details and outcomes according to both interim fluorine-18 fludeoxyglucose positron emission tomography and end-of-chemotherapy fluorine-18 fludeoxyglucose positron emission tomography. ABVD, doxorubicin, bleomycin, vinblastine and dacarbazine; ASCT, autologous stem cell transplantation; eotPET, positron emission tomography response at the end of treatment; HL, Hodgkin lymphoma; IFRT, involved fields radiotherapy; iPET, positron emission tomography response at interim.

Figure 2.

(a) Kaplan–Meier projections of progression-free survival, stratified by end-of-chemotherapy fluorine-18 fludeoxyglucose positron emission tomography (eoc-¹⁸F-FDG-PET) positivity. Log-rank, p = 0.0001. (b) Kaplan–Meier projections of overall survival, stratified by eoc-¹⁸F-FDG-PET positivity. Log-rank p = 0.0001. eocPET, positron emission tomography response at the end of chemotherapy.

Figure 3.

(a) Kaplan–Meier projections of progression-free survival, stratified by positron emission tomography (PET) response at interim (iPET) or at the end of chemotherapy (eocPET). Log-rank p < 0.0001. (b) Kaplan–Meier projections of overall survival, stratified by fluorine-18 fludeoxyglucose (¹⁸F-FDG)-PET response during and after chemotherapy. Log-rank p = 0.00005.