Outcome of childhood ALK-positive anaplastic large cell lymphoma relapses: Real-life experience of the French Society of Pediatric Oncology (SFCE) cohort of 75 French children.

Abstract

To describe treatments and outcomes of French children treated for relapsed/refractory anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK+ ALCL). We conducted the analysis of a series of 75 French children treated for a first relapsed/refractory ALK+ ALCL between 1999 and 2017. The median time to first relapse was 8.1months from initial diagnosis (2.9 after end of treatment), with 12 relapses during frontline treatment or within 1month of the end of treatment. Treatment of the first relapse varied according to the period of time and risk factors: 48 received multiagent chemotherapy, including 21 and 19 consolidated with allogeneic stem cell transplantation (SCT) and autologous-SCT, respectively. Twenty-one patients received weekly vinblastine, and six received ALK inhibitors (ALKi). Overall, 64/75 patients reached a second complete remission (CR2). Eight out of 11 patients who did not reach CR2 died and the other three were rescued with ALKi, vinblastine, and nivolumab. With a median follow-up of 8.2years, 60 patients are alive, 43 in CR2, 15 in CR3, two in CR4; and 15 patients died, six from toxicity and nine from disease progression. The 5-year event-free survival and overall survival after first relapse were 51.7% (95% confidence interval [CI]: 39.6%-62.6%) and 80.7% (95% CI: 69.6%-88.1%), respectively. Time to relapse greater than 12months from initial diagnosis was proven to be a prognostic factor in relapsed/refractory ALK+ ALCL. In relapsed ALK+ ALCL, high survival rate can be reached with various therapeutic strategies. The main challenge remains to prevent subsequent relapses, and to lower long-term morbidity.