Pancreatic cancer: causes

The causes of the development and pathogenesis of pancreatic cancer, like cancer in general, have not been elucidated. However, it is noted that such factors as chronic pancreatitis, cysts and pancreatic injuries, chronic diseases of bile ducts, alcoholism, addiction to very fatty and spicy food, diabetes, radioactive irradiation (in case of violation of occupational safety and in case of emergencies) , some chemical hazards, among which benzidine, beta-naphthylamine are most often mentioned, contribute to the increase in the incidence of cancer.

Pathomorphology of pancreatic cancer. The tumor can be localized in any part of the pancreas or germinate entirely, but usually in 70-75% of cases submitted to different authors, localized in the head of the pancreas, in 20-25% of cases - in the body of it and about 10% - in the region of the tail . Macroscopically represents a bounded gray-white node; can be of different density. The cancer develops from the epithelium of the excretory ducts, or, more rarely, from the parenchyma of the gland. Even less often the tumor develops from the epithelium of pancreatic islets. Adenocarcinomas - the most common type of pancreatic cancer - have a fairly mild consistency and usually relatively rapid growth. Another, also frequent, form of cancer is the scirrus, consisting of small, predominantly polygonal cells with abundant proliferation of connective tissue. Less common are other forms of cancer. Cancers of the pancreas head in most cases are not large, in contrast to the cancerous tumors of her body and tail. The tumor, located in the head of the pancreas, can squeeze the common bile duct, sprout into the duodenum, stomach, liver. Tumors of the body and tail of the gland sprout into the left kidney, spleen, spread along the peritoneum. Pancreatic cancer gives metastases to regional lymph nodes, liver, lungs, adrenal glands, bones, and rarely to other organs. Tumors localized at the tail of the pancreas are more prone to generalized metastasis.

Histologically distinguish cancer in situ, adenocarcinoma, epidermoid cancer, adenoacanthoma and anaplastic cancer. Cancer in situ in the ducts is more common. The most typical for the pancreas is adenocarcinoma, with its predominant scirrhosis variants. There may be sites that have the structure of colloid cancer.

Epidermoid pancreatic cancer is rare, the so-called adenoacanthomes, in which epidermoid structures alternate with areas of glandular cancer, are more frequent. Among the anaplastic crayfish, we can distinguish between the round-celled, spindle cell and polymorphous cell variants. Recently, to clarify the histogenesis of pancreatic cancer, immunohistochemical markers are increasingly used: cancer-embryonic antigen and cancer antigen 19-9.

In the pancreas metastatic cancer, however, is relatively rare (metastases from the stomach and other internal organs). On the other hand, tumors of neighboring organs - the stomach, bile ducts, large intestine - can sprout in the pancreas.

Classification of pancreatic cancer. Usually, four stages of cancer development are distinguished: I and II depending on the size of the tumor (but in the absence of metastases), III and IV with proximal and distant metastases.

• Stage I - tumor diameter does not exceed 3 cm;
• II stage - a tumor more than 3 cm in diameter, but does not go beyond the limits of the organ;
• III А stage - infiltrative growth of a tumor in surrounding tissues (duodenum, bile duct, mesentery, vessels, portal vein);
• III B stage tumor metastasis in regional lymph nodes;
• Stage IV - distant metastases.

There are other classifications of cancer of this localization.

[1], [2], [3], [4], [5], [6], [7], [8], [9]