OBJECTIVETo explore the correlation between UGT1A1 (*28, *60 and * 93) polymorphism and the adverse reactions in small cell lung cancer patients after irinotecan chemotherapy.

METHODSClinical data of 58 small cell lung cancer patients in extensive stage treated in our hospital were retrospectively analyzed. Polymerase chain reaction was used to amplify the UTG, and direct sequencing was performed to determine the UGT polymorphism. The adverse reactions ≥ grade 3 after irinotecan chemotherapy in patients with different UGT genotype were analyzed.

RESULTSAmongthe 58 patients with extensive stage small cell lung cancer, there were 45 (77.6%) cases of wild type UGT1A1*28, 40 (69.0%) cases of wild type UGT1A1* 93, 38 (65.5%) cases of wild type UGT1A1*60, 18 cases of mutation in UGT1A1* 93 and 20 cases of mutation in UGT1A1*60. In UGT1A1 promoter position 28, there were 8 (13.8%) cases of TA5 mutation and 5 (8.6%) cases of TA7 mutation. Among the patients with TA5 mutation, 5 cases had ≥ grade 3 diarrhea, 3 cases had ≥ grade 3 leucopenia and 3 cases had ≥ grade 3 neutropenia, while among the patients with UGT1A1 * 93 mutation, 7 cases had ≥ grade 3 diarrhea, 6 cases had ≥ grade 3 leucopenia and 4 cases had ≥ grade 3 neutropenia.

CONCLUSIONSTA5 and UGT1A1* 93 mutation increase the risk of diarrhea and ≥ grade 3 leukopenia and neutropenia, however, wild type UGT1A1 (*28, * 93, *60) and mutant UGT1A1*60 do not increase those risks. Further prospective study in a larger number of patients is needed to clarify the association between UGT1A1*28, UGT1A1* 93 and UGT1A1*60 polymorphism and adverse reactions of irinotecan, and to help clinicians in choosing a better therapeutic modality for personalized chemotherapy to improve curative effect and reduce adverse reactions.