Real-life study on the use of response adapted therapy in patients with Hodgkin Lymphoma: Results from a multicenter experience.

Few data are known regarding the use of interim positron emission tomography (iPET) after the first two cycles (iPET2) of chemotherapy in treatment-naïve classical Hodgkin lymphoma (cHL) in routine clinical practice, and about the real-life adoption of intensification strategies for iPET positive patients. We conducted a multicenter retrospective study on cHL to investigate the use of iPET in the real-life setting, its prognostic role and outcomes of patients early shifted to intensification. Six hundreds and forty-one patients were enrolled (62% had advanced stage). iPET2 was positive in 89 patients (14%) including 8.7% and 17% early and advanced stage patients, respectively (p = 0.003). Among iPET 2 positive cases treatment was immediately modified in 19 cases; in 14 cases treatment was modified after an additional positive iPET4. Overall 56 iPET2 positive patients never received intensified therapies. Most frequently used intensified therapy was autologous stem cell transplantation followed by BEACOPP. After a median follow-up of 72 months, the 5-year progression-free survival (PFS) was 82% with iPET2 positive patients showing a worse PFS compared with iPET2 negative cases: 31% versus 85%. Focusing on advanced stage patients with a positive iPET2, the 5-year PFS was 59% for patients shifted to intensified therapy at any time point versus 61% for patients who never received intensified therapy. Our study confirmed the higher curability of naïve cHL patients in a real-world setting, and the prognostic role of iPET2 in this setting. A poor adherence to response-adapted strategy which however did not translate into a difference in patient outcomes.