After a few months of treatment with azaserine, some damaged cells began to divide faster than surrounding cells. They can be distinguished from others under the mobile number list microscope. These so-called foci are known as tumor precursors. Certain nitrosamines induce pancreatic tumors in hamsters.

Injection of this nitrosamine can cause abnormal cells to appear in the drainage channel from the pancreas to the intestine. These cells eventually grow into tumors. Pancreatic tumors in humans usually have a tubular structure and also appear to originate from the cells of the draining tubes. The effects of brake nutrients are not easy to study. Often another substance throws a wrench at work The question remains unanswered.