Burden of cancers in the valley of Kashmir: 5 year epidemiological study reveals a different scenario

Cancer is a major burden worldwide but there are marked geographical variations in frequency and incidence overall. The aim of this study was to find the frequency and distribution of commonly occurring cancers in Kashmir, with particular emphasis on urinary bladder cancer. A total of 4,407 cases of histologically confirmed new cancer cases were registered at the Medical Records Department (MRD) of SKIMS from a period between January, 2005 and April 2010. Among 4407 cancers, 2,457 (55.7 %) were men and 1,950 (44.3 %) were women. Stomach cancer is the leading one with an average frequency of 19.2 % followed by esophagus and lung as 16.5 % and 14.6 %, respectively. Stomach (23 %) and lung (21 %) are the leading cancers in men while as esophageal cancer tops (18.3 %) in women followed by breast cancer (16.6 %). This distribution of cancer types is strikingly different from that in the rest of India where oropharyngeal cancer is most common form. Among urinogenital cancers, bladder cancer was observed to primarily affect Kashmiri population (5.9 %) followed by prostate cancer (2.1 %) and renal carcinoma (1.1 %). We conclude that Kashmir is a very high risk area of most commonly occurring cancers particularly cancers of gastrointestinal tract which comprise more than half the frequency of all the cancers.

HRAS T81C polymorphism modulates risk of urinary bladder cancer and predicts advanced tumors in ethnic Kashmiri population

OBJECTIVE

Specific acquired HRAS mutations have been found to predominate in bladder cancer, and HRAS T81C polymorphism has been determined to contribute the risk of various cancers, including bladder cancer.

MATERIALS AND METHODS

We screened the exon 1and 2 of HRAS and frequently detected polymorphism at nucleotide 81T to C (exon 1). A case-control study was conducted using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to test the genotype distribution of 140 bladder cancer patients in comparison with 160 cancer-free controls from a Kashmiri population.

RESULTS

In HRAS T81C SNP, frequencies of TT, TC, and CC genotypes among controls were 84.4%, 15.6%, and 0.0%, while in cases allele frequencies were 64.3%, 30%, and 5.7%, respectively. A significant differences was observed between the control and cases with odds ratio (OR) = 3.0 and 95% confidence interval (CI) = 1.74-5.20 (P = 0.000). Interestingly, combined TC and CC genotype abundantly presented in high grade (OR = 5.4 and 95% CI = 2.8-10.2; P < 0.00) and in advanced tumors (OR = 3.3, 95% CI = 1.71-6.30; P < 0.05). A significant association of the variant allele (TC+CC) was found with male subjects (≥50) and ever smokers (P = 0.001).

CONCLUSION

It is evident from our study that HRAS T81C SNP moderately increases bladder cancer risk, and rare allele is a predictive marker of advanced bladder tumors.