PF313 NEW TREATMENT FOR DOUBLE/TRIPLE HIT LYMPHOMA WITH DOSE INTENSE PROTOCOL: RITUXIMAB,DOXORUBICIN,ETOPOSIDE,PREDNISOLONE/GEMCITABINE+OXALIPLATIN SHAWING BETTER SURVIVAL RATE

Abstract

Background:unclassifiable B‐cell lymphoma with features between diffuse large B‐cell and Burkitt, Burkitt‐like with a complex karyotype involving MYC and BCL‐2 genes (double hit) and BCL‐6 gene (triple hit). This kind of lymphoma shows high mitotic rates and an aggressive course for which no definitive treatment have been established so far.Aims:the study is aiming at evaluating a new dose intense chemotherapy in patients with double/triple hit lymphoma with end points including progression free and overall survival at 5 years.Methods:this is a multicenter study with Al Bairouni university cancer center in Damascus, Syria as the main investigator performed between 2014 and 2018 where we recruited 66 patients with ages between 18 and 65 years having double/triple hit lymphoma confirmed by immuno‐histochemistry as well as FISH technique. Patients received a dose intense protocol as follows: (Rituximab 375 mg/m2 with Doxorubicin 75 mg/m2, Cyclophosphamide 1200 mg/m2, Etopdside 300 mg/m2 and Prednisolone 1 mg/kg for 5 days) repeated every 21 days for 6 cycles with 5 days G‐csf support. Then partial and complete responders were given (Gemcitabine 1gr/m2+ Oxaliplatin 85 mg/m2) for 6 cycles repeated every 14 days. End‐points were progression free survival and overall survival at 5 years.Results:overall response rate (ORR) was documented in 58 patients (87.8%) (42 complete responders and 16 partial responders). 12 patients progressed at different stages of follow up with a progression free survival (PFS) of 82% (95% CI 77–88). However, 51 patients were found to still alive at 5 years with an overall survival (OS) rate of 77.2(95% CI 71–82). Survival was shorter in those presented with synchronous central nervous system and abdominal localizations (P value 0.02). The most frequent toxicities were, neutropenia and thromcytopenia of different grades, tumorlysis syndrome in few patients and different degrees of mucositis and peripheral neuropathy, however, no documented death was attributed to toxicity profile.Summary/Conclusion:double/triple hit lymphoma is a new subtype of lymphoma involving a 2–3 genes abnormalities which increase the aggressiveness course of disease with most patients resisting the old standards. Recently, patients were responding to the classical R‐CHOP as well as to R‐EPOCH in both young and elderly patients, however, survival rates were not exceeding 65% at 5 years. That is why we have developed this protocol with high dose chemotherapy in order to overcome resistance and consolidate the primary response. Compared with studies published in the literature, our protocol confers better progression free and overall survival rates, however, bigger trials should be performed to validate our results