This study, conducted in Germany, also indicated a dose-dependent increase in cancer risk: 10 units of insulin glargine increased the risk by 9% whereas 50 units increased it by 31%. As a result of these findings, studies were also conducted in databases from Sweden, Scotland, and the United Kingdom. The Swedish study found that compared with patients on other forms of insulin, patients receiving Glargine alone had a two-fold increased risk for breast cancer. The Scottish study found a nonsignificant increased risk for breast cancer whereas the UK study found no link between insulin glargine and any type of cancer.

“The studies are conflicting and loose. Cancer is a multifactorial disease, one of the major reasons is obesity which makes diabetics more prone to the process. These are all observational studies and need more research,” said Anoop Misra, head of Diabetes and Metabolism at the Fortis Hospital in Delhi.

Others agree. “We get about 30 to 40 calls daily from panic-stricken patients. These are small observational studies. Doctors in India have given statements saying that they won’t stop prescribing the drugs. The drug does act on the growth-promoting cells but not substantial enough to cause cancer,” said S K Wangnoo, Senior Endocrinologist at Indraprastha Apollo Hospital, Delhi.