Epidemiological data show that the risk of adenocarcinoma and colorectal cancer is influenced by many factors, including age, familial genetic factors, obesity, exercise, race, metabolic syndrome, and alcohol abuse. In addition to this, there are gender differences in the development of colorectal cancer. A growing number of studies have shown that men develop adenoma and colorectal cancer at an earlier age and at a higher rate than women. Using animal models, U.S. researchers have revealed that differences in sex hormones between the sexes contribute to different cancer risks. The researchers verified this gender difference in cancer risk in an ApcPirc/+ (Pirc) rat model of early-stage colon cancer: male rats developed adenomas twice as much as females. Analysis of large data sets also showed that ApcMin/+ rats also showed a higher susceptibility to adenocarcinoma in males, but only in the colon. In addition, wild mice injected with the carcinogen, azoxymethane (AOM), showed an increase in the number of males developing colonic adenomas. The researchers further explored the effect of hormones on these phenomena. It was found that the incidence of adenomas in female mice was not altered after removal of estrogen or replacement of one or all of the estrogens using ovariectomy. In contrast, removal of androgens from male mice using orchiectomy (castration) significantly prevented the development of adenocarcinoma in Pirc mice, while testosterone supplementation reversed this protective effect. These findings were similarly validated in the AOM mouse model. In addition, androgen receptors were not found in colon cancer or adenomas; therefore, testosterone may act indirectly on tumors. The results of this study suggest that the indirect pro-carcinogenic effect of testosterone may explain the variability in colon adenoma development between the sexes. Other causes of colon adenocarcinoma? 1. Genetic factors: If a person has a first-degree relative such as a parent who has had colon cancer, the risk of developing this disease is 8 times higher than normal and is a common cause of colon cancer. About 1/4 of new cases have a family history of colon cancer. Familial colon polyposis is an autosomal dominant disease with a prevalence rate of up to 50% in the family, and without treatment, there is a possibility of colon cancer after the age of 10. 2, colorectal adenoma: autopsy material research found that the incidence of colorectal adenoma is basically the same as colorectal cancer, and is also a common cause of colon cancer. According to statistics, the incidence of colorectal cancer is 5 times higher in patients with single adenoma than in those without adenoma, and 1 times higher in those with multiple adenomas than in those with single adenoma. Choroidal adenoma-like polyps are prone to develop into cancer, with a malignancy rate of about 25 percent, and tubular adenoma-like polyps have a malignancy rate of 1 to 5 percent. 3.Environmental factors: It has been proved that among various environmental factors, dietary factors are the most important, and the incidence of colon cancer is positively related to the high fat consumption in food. In addition, the etiology of colon cancer may also be related to the lack of trace elements and change of living habits. 4.Chronic inflammation of colon: It is reported that the prevalence of intestinal cancer is positively correlated with the endemic area of schistosomiasis, and it is generally believed that inflammatory changes in the intestine due to schistosomes, some of which will become cancerous. Other chronic inflammatory conditions of the intestine also have the potential to become cancerous, such as patients with Crohn’s disease or ulcerative colitis have 30 times the risk of developing colon cancer than the norm. This is one of the more common causes of colon cancer.