Patient selection

The pharmacy and medical records of all patients who underwent an AuSCT for RRHL between November 2007 and October 2021 were reviewed. All patients who received lenalidomide with or without dexamethasone for relapsed (recurrence of HL after a previous complete remission) or progressive disease (disease progression without a previous complete remission) post AuSCT were included in this single-center retrospective analysis. The choice of treatment for post AuSCT relapse was at the discretion of the treating clinician, and no specific policy was followed for selecting patients for lenalidomide-based therapy. It may be noted that, checkpoint inhibitors were not available for a large part of the study period, and anti-CD30 therapies such as brentuximab were unavailable for the entire study period. Therefore, patients with post AuSCT relapse did not have significant treatment options available. Those who received lenalidomide as a maintenance strategy were excluded. Data were updated until November 30, 2021. The study was approved by the institutional ethics committee (IEC-III) of Tata Memorial Centre (protocol number 900946) and was carried out in accordance with the principles in the Declaration of Helsinki. The need for an informed consent was waived off, considering the nature of the study.