I'm using PVs as a healthier replacement for cigarettes at the moment but in the future I will stop using nicotine altogether. Since nicotine has been linked to increased risk for pancreatic cancer I can't justify using PVs forever even though I would like to.
1: BMC Cancer. 2009 Jul 29;9:256
The relation between smokeless tobacco and cancer in Northern Europe and North America. A commentary on differences between the conclusions reached by two recent reviews.
BACKGROUND: Smokeless tobacco is an alternative for smokers who want to quit but require nicotine. Reliable evidence on its effects is needed. Boffetta et al. and ourselves recently reviewed the evidence on cancer, based on Scandinavian and US studies. Boffetta et al. claimed a significant 60-80% increase for oropharyngeal, oesophageal and pancreatic cancer, and a non-significant 20% increase for lung cancer, data for other cancers being "too sparse". We found increases less than 15% for oesophageal, pancreatic and lung cancer, and a significant 36% increase for oropharyngeal cancer, which disappeared in recent studies. We found no association with stomach, bladder and all cancers combined, using data as extensive as that for oesophageal, pancreatic and lung cancer.
CONCLUSION: When conducting meta-analyses, all relevant data should be used, with clear rules governing the choice between alternative estimates. A systematic meta-analysis using pre-defined procedures and all relevant data gives a lower estimate of cancer risk from smokeless tobacco (probably 1-2% of that from smoking) than does the previous review by Boffetta et al.
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Now this is for smokeless tobacco. The nicotine in E-cigs should provide a risk-profile comparable to NRT products. I couldn't find anything on PubMed that implicated non-tobacco nicotine products in pancreatic cancer.
There is one study where they used injected nicotine on pregnant female rats, and found some damage to pancreatic cells in the offspring, but I don't think you can extrapolate from this study a significant increase in the risk for pancreatic cancer in humans who use non-injected nicotine.
From what I have read, being diagnosed with diabetes after age 50 significantly raises odds of pancreatic cancer. There is a non-significant increase in incidence among ever-smokers.
The following table gives the estimated numbers of new cases and deaths for each common cancer type:
Cancer TypeEstimated New CasesEstimated DeathsBladder70,98014,330Breast (Female - Male)192,370 - 1,91040,170 - 440 Colon and Rectal (Combined)146,97049,920Endometrial42,1607,780Kidney (Renal Cell) Cancer 49,096 11,033 Leukemia (All)44,79021,870Lung (Including Bronchus)219,440159,390Melanoma68,7208,650Non-Hodgkin Lymphoma65,98019,500Pancreatic42,47035,240Prostate192,28027,360Skin (Nonmelanoma)>1,000,000<1,000Thyroid37,2001,630
Common Cancer Types - National Cancer Institute