It is believed that continuous exposure to toxic substances in upper respiratory tract and GIT have been underlined as the cause for majority of esophagus cancer cases. However, other cases that pre-dispose people to esophagus cancer is infection coupled with immune-depression. This has been seen in many patients with the human papilloma virus (HPV) infection.Some studies have traced genes from human papilloma virus (HPV) and have been found in up to one-third of esophagus cancer tumors in some patients.The human papilloma virus is a group of more than 90 viruses of various types and is called papilloma viruses because they possess warts-like growth called a papilloma. Infection with some types of human papilloma virus is linked to various cancerous diseases that include throat cancer, cervical and anal cancer.People who have been exposed more frequently to esophagus cancer are those with immune-depression as seen in advanced HIV/Aids infection. Patients with immune-depression from HIV/Aids tend to suffer from esophagus cancer because of reduced resistance from oral flora and infections. Other cancers linked to esophagus cancer include mouth and throat cancer.For esophagus cancer, there are other risk factors to consider that predispose people to many chances of getting esophagus cancer. This is because different cancers have different risk factors. Various risk factors predispose people to the benign cancer of the esophagus ‘the adenocarcinoma’ whereas others are predisposed to the malignant type of the squamous cell carcinoma of the esophagus.It should be noted that having one or many risk factors does not necessarily mean that a person will suffer from the disease. For the disease to develop, it might take longer than expected or can emerge due to other associated factors.In Rwanda, esophagus cancer is more common in men and has been seen in men above 60 years of age. For many cases of esophagus cancer that has no other underlying chronic illness, tobacco and alcoholism have been noted as most predisposing factor. These risk factors create the difference of occurrence between men and women of the same age bracket.The use of tobacco products such as cigarettes, cigars, pipes, and chewing tobacco predispose people to esophageal cancer. The frequency of use is considered. For example, the longevity of use leads to higher cancer risks. Someone who smokes a pack of cigarettes a day or more has at least twice the chance of getting the squamous cell or adenocarcinoma of the esophagus than a person who does not smoke.Drinking alcohol also increases the risk of esophageal cancer. The chance of getting esophageal cancer goes up with higher intake of alcohol. Alcohol affects the risk of the squamous cell type more than the risk of adenocarcinoma. Alcohol and tobacco contain toxic substances that constantly irritate and inflame the esophagus inner lining to cause cancer. A combination of both factors further increases the risk of esophageal cancer.Gastric acid reflux has been found to cause the esophagus cancer due to continuous irritations and inflammatory reactions caused by the stomach acid.This has been seen in patients with the Barrett disease and gastro-esophageal reflux disease. In the Barrette disease, the reflux of stomach acid into the lower esophagus normally occurs over a prolonged period of time that damages the lining of the esophagus. Barrett’s esophagus increases the risk of adenocarcinoma of the esophagus. This is because the gland cells in Barrett’s esophagus that replace the normal lining of esophagus cells because of acid erosion can become more abnormal over time. If the abnormality occurs, then it leads to dysplasia, a pre-cancerous condition. It is usually graded by how abnormal the cells look under the microscope. High-grade dysplasia is the most abnormal and is linked to the highest risk of cancer.In the gastro-esophageal reflux disease, people normally present with heartburn sensation and persistent chest pains caused by irritations from the acid. Persistent hiccups have also been seen in people with this problem.People with both the barrettes disease and gastro-esophageal reflux tend to have high risks of developing esophagus cancer in advanced age of life.Dr Joseph Kamugisha is a resident oncologist in Jerusalem, Israel