Influence of UGT1A1 *6/*28 Polymorphisms on Irinotecan-Related Toxicity and Survival in Pediatric Patients with Relapsed/Refractory Solid Tumors Treated with the VIT Regimen

Abstract

Xiaoqin Zhu,1,2,* Jia Zhu,1,2,* Feifei Sun,1,2,* Zijun Zhen,1,2 Dalei Zhou,1,3 Suying Lu,1,2 Junting Huang,1,2 Yi Que,1,2 Lian Zhang,1,2 Ruiqing Cai,1,2 Juan Wang,1,2 Yizhuo Zhang1,2 1State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, People’s Republic of China; 2Department of Pediatric Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, People’s Republic of China; 3Department of Molecular Diagnostics, Sun Yat-Sen University Cancer Center, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yizhuo Zhang; Juan Wang Email [email protected]; [email protected]: The association between UGT1A1*6/*28 polymorphisms and treatment outcomes of irinotecan in children remains unknown. This retrospective study investigated the influence of UGT1A1*6/*28 polymorphisms on irinotecan toxicity and survival of pediatric patients with relapsed/refractory solid tumors.Methods: The present study enrolled a total of 44 patients aged younger than 18 years at Sun Yat-sen University Cancer Center between 2014 and 2017.Results: There were 26 boys and 18 girls; the median age at first VIT course was six years (range: 1– 18 years). The tumor types included neuroblastoma (n = 25), rhabdomyosarcoma (n = 11), Wilm’s tumor (n = 4), medulloblastoma (n = 2), and desmoplastic small round cell tumor (n = 2). Overall, 203 courses of VIT regimens were prescribed. Neither UGT1A1*6 nor *28 polymorphisms were associated with the incidence rates of severe (grade III–IV) irinotecan-related toxicities, but tended to reduce the patient overall survival (UGT1A1*6, P = 0.146; UGT1A1*28, P = 0.195). Moreover, patients with mutant UGT1A1*6 genotypes were more likely to develop grade I–IV irinotecan-related diarrhea (P = 0.043) and anemia (P = 0.002). Overall, the UGT1A1*28 polymorphism may play a protective role against irinotecan-related diarrhea and abdominal pain.Conclusion: In relapsed/refractory pediatric solid tumors, the UGT1A1*6 polymorphism was a risk factor of irinotecan-related diarrhea and anemia. The UGT1A1*28 polymorphism may serve a protective role in irinotecan-related abdominal pain and diarrhea. Both mutations had a tendency to be risk factors for survival. Nevertheless, prospective studies are required to verify such conclusions.Keywords: UGT1A1 *6/*28 polymorphism, irinotecan toxicity, pediatric, relapsed/refractory solid tumors

Keywords

• ugt1a1 *6/*28 polymorphism
• irinotecan toxicity
• pediatric
• relapsed/refractory solid tumors