PB2018 MANTLE CELL LYMPHOMA (MCL): A SINGLE CENTRE EXPERIENCE ON THE OUTCOME OF MCL BEFORE AND AFTER THE EMERGENCE OF NOVEL THERAPIES.

Abstract

Background: Mantle cell lymphoma (MCL) is a B cell malignancy accounting for 3-10% of all Non-Hodgkin Lymphomas and arises mainly in older adults with a male predominance (McKey et al). Historically, median survival was 4–5 years (Herrmann et al, 2009) however this is now in the order of 8–12 years in younger fitter patients who are able to tolerate intensive therapies (Eskelund et al, 2016). The current standard treatment is chemoimmunotherapy with or without autologous stem cell transplantation (ASCT). Although intensive therapy can achieve durable responses most patients eventually succumb to their disease. Novel therapeutic agents have shown efficacy in relapsed/refractory disease and are now being tested as frontline treatment (Sharma et al., 2018). Aims: We report a single centre experience of MCL and its treatment. Methods: Retrospective data was collected on all patients diagnosed with MCL at Ipswich Hospital NHS Trust over a nine year period between January 2010 and January 2019. Results: Forty-two patients were included in the analysis. Median age was 68yrs with a male to female ratio of 5:1. Eastern Co-operative Oncology Group (ECOG) performance status ranged from 0-1 in 66%, ≥2 in 14% and 19% had no status documented. Twenty-four patients (57%) received a non-intensive chemoimmunotherapy regimen; rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or rituximab-bendamustine (BR) as first line treatment with twenty of these patients receiving rituximab maintenance. Thirteen patients (31%) were fit enough to receive an intensive chemoimmunotherapy regimen with all but one consolidated with an ASCT. Of those transplanted five went on to receive rituximab maintenance. The remaining 12% of patients received either R-Chlorambucil, palliative radiotherapy, FCR or supportive care. The median Kaplan-Meier overall survival (OS) for all patients had not been reached. Median progression free survival (PFS) was 48 months. Comparing first line therapies, the median OS for those that received RCHOP/BR was 60 months with a median PFS of 35 months vs. not reached for both OS and PFS with intensive chemoimmunotherapy followed by ASCT. Eighteen patients had relapsed during the nine year period. There was no standard second line treatment. Eight patients received further chemoimmunotherapy including BR, R-cytarabine and FCR, one PEP-C, three ibrutinib, four palliative radiotherapy and two received supportive care only. After first relapse median PFS was 6 months and median OS was only 10 months. Nine patients received a third line treatment, of which 3 received ibrutinib and one venetoclax and the median OS was 9 months. The six relapsed/refractory patients that received Ibrutinib at either first or second relapse had a median OS of 8 months vs. 12 months in those that received other forms of therapy. Summary/Conclusion: As expected the best outcomes were with high intensity regimens consolidated by ASCT. Our data period was not long enough to show the continuous pattern of relapse despite durable responses that have now been shown by long term follow up data (Eskelund et al, 2016). The outlook was poor for relapsed/refractory disease with a median OS of 10 months. Rule et al analysed data from 370 patients receiving ibrutinib for relapsed/refractory MCL, enrolled across three different studies (PCYC-1104, SPARK, and RAY), and demonstrated an excellent outcome, with a median PFS of 13 months and median OS of 26.7 months. We did not see a beneficial effect on OS with the use of novel therapies in our patients (8 months vs. 12 months) although our study numbers were small.