Intramucosal carcinoma

Intramucosal carcinoma describes an early stage of cancer where abnormal cells are still limited to a thin layer of tissue called the mucosa. Cancers treated at this stage are less likely to spread to other body parts.

Is intramucosal carcinoma a type of cancer?

Yes, intramucosal carcinoma is a type of cancer, but it is considered very early-stage. Because the cancer cells remain confined to the mucosa, the risk of these cells spreading to other body parts is very low. Intramucosal carcinoma is recognized as a highly treatable form of early-stage cancer.

What are the symptoms of intramucosal carcinoma?

Many people with intramucosal carcinoma do not have any symptoms. When symptoms do occur, they usually depend on which organ is affected. For example, intramucosal carcinoma of the stomach may cause mild indigestion or stomach pain, while intramucosal carcinoma of the colon might cause slight bleeding or changes in bowel habits. Often, it is found incidentally during routine screening tests.

What causes intramucosal carcinoma?

The cause of intramucosal carcinoma depends on the area of the body involved. For example, intramucosal carcinoma of the stomach may be caused by chronic inflammation due to infection with Helicobacter pylori bacteria. In the colon, it often arises from precancerous growths called polyps, which may develop due to diet, genetic factors, or chronic inflammation. In the esophagus, chronic acid reflux or Barrett’s esophagus may lead to intramucosal carcinoma. Although certain risk factors are known, the exact cause in some cases remains unclear.

What stage is intramucosal carcinoma?

Intramucosal carcinoma is an early-stage cancer. It differs from carcinoma in situ, when cancer cells are still limited to the epithelium, the most superficial layer of the mucosa. Intramucosal carcinoma means that cancer cells have spread deeper, specifically into the lamina propria layer of the mucosa, but have not yet invaded through the muscularis mucosae, which separates the mucosa from deeper tissue layers. The stage assigned to intramucosal carcinoma depends on the organ involved but typically remains at an early and highly treatable stage.

Is intramucosal carcinoma the same as high grade dysplasia?

Intramucosal carcinoma is not the same as high grade dysplasia. High grade dysplasia refers to precancerous changes where cells show severe abnormalities but remain within the epithelium (surface layer). Intramucosal carcinoma is a step further, where cancer cells have moved beyond the epithelium into the lamina propria, making it an early form of invasive cancer. Although both conditions are considered early stages with excellent prognosis, intramucosal carcinoma indicates a slightly more advanced disease compared to high grade dysplasia.

How is this diagnosis made?

The diagnosis of intramucosal carcinoma is usually made by examining a biopsy (small tissue sample) under a microscope. The biopsy is taken during a procedure such as an endoscopy or colonoscopy, depending on the location of the abnormal tissue. A pathologist will examine the biopsy sample closely to determine whether the abnormal cells are confined within the mucosa or have begun to invade deeper layers. Additional tests, such as imaging or further biopsies, may be recommended to confirm the extent of the disease.