Role of Positron-Emission Tomography in Prognosis of Outcomes of High-Dose Chemotherapy with Autologous Hematopoietic Stem Cell Transplantation in Hodgkin’s Lymphoma

Abstract

Aim. To perform a comparative analysis of the prognostic significance of positron-emission tomography (PET) with other prognostic factors of the efficacy of high-dose chemotherapy (HDCT) with autologous hematopoietic stem cell transplantation (auto-HSCT) in patients with Hodgkin's lymphoma. Methods. Data on 84 patients with Hodgkin's lymphoma receiving treatment over the period from October 2007 till November 2015 were analyzed. The median age was 26.6 years (range: 10-62). The median follow-up was 25 months (range: 1-81 months). The prognostic significance of sex, response to the initial chemotherapy, time to relapse, second-line chemotherapy regimen type, B-symptoms, tumor size (>5 cm in cases of relapse prior to the HDCT), serum LDH and albumin levels, CT findings, the number of chemotherapy lines, conditioning regimen before the auto-HSCT, and the metabolic activity before the HDCT (PET1, n = 82) and after auto-HSCT (PET2, n = 57) was analyzed. Results. The two-year overall (OS) and event-free (EFS) survival rates were 70.6 % and 58.7%, respectively. Prognosis was the worst in patients with CT-confirmed lymphoma progression by the initiation of HDCT. In the presence of a CT-response, the PET status of lymphoma has a prognostic significance. The 2-year OS and EFS rates of PET1-negative and PET1-positive patients were 82 % vs. 62 % (p = 0.056) and 74 % vs. 44 % (p = 0.003), respectively. In PET2-negative and PET2-positive patients, the OS and EFS rates were 90 % vs. 65 % (p = 0.013) and 72 % vs. 52 % (p = 0.014), respectively. From the prognostic point of view, PET2 findings prevailed over PET1 findings. The multivariate analysis confirmed only PET2 significance for OS prediction. Conclusion. The tumor sensitivity to the chemotherapy assessed by the CT is the most important prognostic factor. In case of a positive CT dynamics, the achievement of PET1 or PET2 negativity before or after HDCT/auto-HSCT is a favorable prognostic factor. The worst prognosis was observed in patients with tumor metabolic activity before or after HDCT/ auto-HSCT.