The Relationship Between Esophageal Cancer and Various Risk Factors

Esophageal cancer is a serious disease that threatens human health. This article aims to explore the relationship between esophageal cancer and various risk factors, including esophageal stenosis, hot tea consumption, fern consumption, plant irritants, and fungal infections.

　　I. Relationship Between Esophageal Stenosis and Esophageal Cancer

The esophagus is the passage for food and liquids entering the body. It may be damaged by substances passing through, leading to cancer. Esophageal cancer is associated with stenosis, especially stenosis caused by corrosive damage. Research shows that in 63 cases of esophageal cancer caused by alkali burns, the average latency period was 41 years. Dunbarm's study found that esophageal narrowing had a significant impact on the induction of esophageal cancer in hamsters by benzo(a)pyrene. Papillomas and cancer lesions occurred earlier and more severely near the proximal end of the narrowing.

　　II. Relationship Between Hot Tea Consumption and Esophageal Cancer

Drinking hot tea may have an impact on the occurrence of esophageal cancer. The Guryev region and Aktubinsk province in Kazakhstan, as well as some other high-incidence areas such as northeastern Iran, Puerto Rico, and the Chaoshan area in Guangdong province, have residents who drink large amounts of hot tea daily. However, a paired case-control study of 301 esophageal cancer cases did not find significant differences. In Linxian, a high-incidence area of esophageal cancer, dietary habits of eating hot, hard, coarse, and fast food may be related to the occurrence of esophageal cancer.

　　III. Relationship Between Fern Consumption and Bladder Cancer, and Tannins and Cancer

There have been reports that consuming ferns is associated with chronic endemic hematuria in animals and bladder cancer in cattle. Ferns can induce intestinal cancer, bladder cancer, and other tumors in experimental animals, indicating that they may contain chemical carcinogens. However, Morino et al. did not find any carcinogenic effects of quercitin or rutin in animal experiments. Tannins are complex polymers with different chemical properties in different plants. Subcutaneous injection of different tannin extracts can induce tumors in rats and mice. In Curacao, an island with a high incidence of esophageal cancer, local residents take plant tannins as tea or medicine, which may be related to the occurrence of esophageal cancer on the island.

　　IV. Relationship Between Plant Irritants and Esophageal Cancer

Plant irritants in food, such as plant stones, spines, and thorns, may be related to the occurrence of esophageal cancer in the Transkei region. Most plants can absorb silica from the soil and deposit it in the form of opal on the surface layer of leaves to strengthen plant stems and thorns. These silica particles have a certain shape and diameter of 15 - 20 microns, known as plant stones. It is speculated that these sharp objects in food boluses can scratch the narrow esophagus. Corn contains many quartz particles after being ground by stone tools, and there is a lot of chaff in the air. Silicosis has been found in young women in the Transkei region, which is believed to be related to the two processing methods. These irritants have a chronic damaging effect on the esophagus and may be one of the reasons for the occurrence of esophageal cancer in the Transkei region.

　　V. Relationship Between Fungal Infection and Esophageal Cancer

Certain fungal infections and invasion of esophageal tissues may cause inflammation, epithelial hyperplasia, metaplasia, and even canceration through local irritation. Xia Qiujie et al. examined 155 human esophageal biopsy specimens collected from Linxian and other regions, including 30 cases of early cancer and cardia cancer. The results showed that hyperplastic epithelium, early cancer tissue, and hyperplastic epithelium next to early cancer all had varying degrees of fungal infection. Fungal infection, especially Candida albicans, may be related to the hyperplastic growth of esophageal epithelium. They speculate that fungal infection and invasion of esophageal tissues may be related to the occurrence of esophageal cancer.

In conclusion, esophageal cancer is related to multiple factors. Further research is needed to better understand the mechanisms of these factors in the occurrence of esophageal cancer and to provide scientific basis for prevention and treatment.