Safety And Efficacy Of SBRT And Particle Therapy For Pancreatic Cancer:A Systematic And Meta-analysis

ObjectiveTo evaluate the safety and efficacy of SBRT and particle therapy for pancreatic cancer(PC).MethodsThe databases were electronically searched to collect the studies about the SBRT and particle therapy for PC from inception to June 2019.Two reviewers independently screened literature and extracted data.Primary outcome measures:Overall survival(OS),local control(LC),freedom from local progression(FFLP),progression-free survival(PFS)and incidence of adverse reactions(gastrointestinal ulcers and gastrointestinal reactions,etc.).A Meta-analysis was performed by STATA12.0 and MetaAnalyst Beta 3.13 software.Descriptive analysis was used for outcome measures that could not be combined.Results1.A total of 35 studies involving 2141 PC patients were included in the Meta analysis of SBRT for pancreatic cancer.The incidence of grade 2,3,4,and 5gastrointestinal(GI)ulcer toxicities in PC patients treated with SBRT were 4%,2%,2% and 0.The incidence of grade 2,3,and 3 gastrointestinal reactions were 21%,5%and 5%.No patients developed grade 2 or higher radiation dermatitis,anorexia.The1-and 2-year OS rates were 54% and 25%.The 1-year FFLP was 88%.and the 1-year and 2-year PFS were 40% and 11%,respectively.2.A total of 8 studies involving 368 PC patients were included.The incidence of grade 2,3,and 5 GI ulcer toxicities in PC patients treated with carbon ion/proton therapy were 7%,2% and 0.The incidence of grade 2,3,and 3 gastrointestinal reactions were 11%,7% and 7%.The incidence of grade 2,3 and 4 anorexia toxicities were 6%,3% and 0,respectively.The 1-and 2-year OS rates were 77% and 45%.The2-year LC,1-year FFLP and 1-year LR rates were 81%,88% and 15%,respectively.The incidence of grade 2,3 GI ulcer toxicities in carbon ion and proton therapy for PCwere 7%,2% and 4%,8%(P>0.05);and the 1-and 2-year OS were 77%,44% and78%,50%(P>0.05).ConclusionsParticle and SBRT are safe and effective to treat pancreatic cancer(PC).Both methods are significantly effective in improving the LC and OS of PC,with low radioactivity and less toxic and side effects,providing patients of PC with time to systemic treatment,and avoiding delay of optimal time to systemic treatment due to a long cycle of radiotherapy.As an emerging radiotherapy technology/pattern,particle and SBRT in the treatment of PC has obvious advantages,which may bring revolutionary changes for the treatment and overcome of PC.Compared with SBRT,particle can prolong OS without increasing toxic reaction.So far,the particle used in the clinical setting is dominated by carbon ion and proton.By comparison,carbon ion and proton have similar safety and efficacy in the treatment of PC.However,limited by the quantity and quality included in the present study,it is necessary to fully evaluate the benefit-risk ratio in different therapeutic settings before popularizing carbon ion/proton therapy for PC globally.