Title: Association of polymorphism of Enzyme Thiopurine Methyl Transferase in Head & Neck Squamous Cell Cancer and treatment response to Concurrent Chemo Radiotherapy

Authors: Sandip Barik, Sudhir Singh, Seema Gupta, Naseem Jamal, Devendra Parmar, Ankur Dhawan, MLB Bhatt

 DOI:  https://dx.doi.org/10.18535/jmscr/v5i4.177

Abstract

Objectives: The aim of the present study was to determine the frequency of the functional TPMT polymorphisms and their association with the treatment outcome in patients of HNSCC receiving cisplatin based chemoradiation.

Methods: 100 patients of locally advanced head & neck squamous cell carcinoma and 100 controls frequently matched with cases were enrolled in the study. Allelic variant of TPMT gene was done with the help of RFLP PCR analysis. All patients received radiation 70 Gy with concurrent cisplatin 35 mg/mevery weekly. Response assessment was done with help of World Health Organization (W.H.O.).

Results: Majority of Indian population had TPMT*3B wild genotype. The patients carrying the wild type genotype of all four alleles responded to Chemoradiation, while TPMT*3B heterotypes and TPMT *3C homozygous mutant form were found among the non responder patients.

Conclusion: Genotyping of TPMT helps us to identify responders and non responders to standard treatment and enhances the precision regarding selection of treatment modality.

Keywords: Head and Neck Cancer, Thiopurine Methyltransferase gene, Treatment Response, Polymorphism.

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Corresponding Author

Dr Sandip Barik

Consultant Radiation Oncology, HCG Regency Cancer Center,

A4 Sarvodaya Nagar, Kanpur-208005, Uttar Pradesh

Email: This email address is being protected from spambots. You need JavaScript enabled to view it., Mobile no-09450381454