Types of Non-colorectal Gastrointestinal Cancers

Introduction

Non-colorectal gastrointestinal cancer are malignancies affecting parts of gastrointestinal organs other than the intestines. It includes the pancreas, gastric (stomach) region, esophagus, and hepatic organs like the liver or gallbladder. The symptoms vary depending on the organ affected and the severity of the cancer. The ideal treatment procedure for cancer is chemotherapy, radiation, or surgical intervention. However, the sequence and choice of treatment procedures depend upon the severity of the malignancy.

What Are the Different Types of Non-colorectal Gastrointestinal Cancers?

There are different types of non-colorectal gastrointestinal cancers affecting various internal organs. This includes:

Pancreatic Cancers

The cancers affect the pancreas and lead to uncontrolled growth of cells and tissues. The most common type of pancreatic cancer is pancreatic adenocarcinoma, and the least common is pancreatic neuroendocrine tumors. Some other pancreatic cancers are squamous cell carcinoma, signet cell carcinoma, and ampullary cancers.

• Pancreatic Adenocarcinoma: It is also known as ductal carcinoma. It accounts for approximately 90 % of pancreatic cancer cases, thus considered the most common type of pancreatic cancer. Cancer affects the lining of the pancreatic ducts or the enzyme-secreting cells of the pancreas (acinar cell carcinoma). The symptoms include nausea, abdominal pain, and weight loss. Due to an increase in enzyme concentration, some patients may have skin rashes and joint pains. Jaundice is not a very common symptom in such cases.

• Squamous Cell Carcinoma: A very rare non-endocrine cancer of the pancreatic ducts, made up of only squamous cells. The malignancy is rare because the squamous cells are not seen frequently in the pancreas. The prognosis is often very poor because the lesion is diagnosed after metastasis.

• Adenosquamous Carcinoma: Although a rare malignancy, but more aggressive than adenocarcinoma with a poor prognosis. These cancers show characteristics of both squamous cell carcinoma and adenocarcinoma.

• Colloid Carcinoma: It is a rare type of exocrine pancreatic cancer comprising only 1% to 3% of total exocrine cancers. The tumor is formed from a benign cyst known as IPMN (intraductal papillary mucinous neoplasm). Colloid carcinoma is easy to treat and does not spread as compared to other cancers because the malignant float in a gelatinous substance known as mucin. It possesses a better prognosis than other malignant conditions.

• Neuroendocrine Pancreatic Cancer: NETs (neuroendocrine tumors) develop from the cells of the pancreas, which secrete hormones like insulin and glucagon to regulate blood sugar levels. These are also called endocrine or Islet cell tumors.

Stomach Cancers

The cancers affect the stomach gradually over many years.

Types of stomach cancers are:

• Adenocarcinoma: It comprises almost 90 % of cancers of the stomach. These develop from the glands' cells present in the stomach's innermost lining. There are two major types of stomach adenocarcinomas:

1. Intestinal types of cancers have a better prognosis.

2. Diffuse types of cancers grow very rapidly and are harder to treat.

• Gastrointestinal Stromal Tumors (GISTs): The rare type of tumor that forms in the interstitial cells of Cajal. These gastrointestinal stromal tumors have the tendency to grow into other areas and gradually spread to other parts of the body. The GISTs can start proliferating anywhere in the digestive tract but often in the stomach.

• Neuroendocrine Tumors: These tumors include carcinoids. Neuroendocrine tumors grow in the cells of the stomach and other digestive organs, which act like nerve cells and hormone-secreting cells. These tumors grow slowly and often do not spread to other organs.

• Lymphomas: Cancers affecting the lymphocytes. Generally, it starts in other organs but can also initiate in the walls of the stomach.

• Some other rare cancers of the stomach are leiomyosarcomas, squamous cell carcinoma, or small cell carcinomas.

Esophageal Cancers

Malignancy affects the esophagus causing uncontrolled growth of the lining of the esophagus. Generally, cancer starts in the inner layer of the esophagus wall and grows outwards through other outer layers.

Types of esophageal cancers are:

• Squamous Cell Carcinoma: Squamous cells line the inner layer of the esophagus. The uncontrolled growth of squamous cells causes this carcinoma. The most common site of squamous cell carcinoma is the cervical esophagus (neck region) and the chest cavity's upper two-third region (middle and upper thoracic esophagus).

• Adenocarcinoma: Cancers in the gland cells of the esophagus are called adenocarcinomas. It generally affects the lower third of the esophagus (lower thoracic esophagus).

• Gastroesophageal Junction Tumors: Adenocarcinomas originate in the esophagus and stomach junction.

• Some rare cancers of the esophagus are melanomas, sarcomas, and lymphomas.

Liver Cancers

Cancer in the liver cells. Some of the liver cancers are:

• Hepatocellular Carcinoma: It is the most common form of liver cancer in adults. It has two patterns of growth:

1. Some tumors begin as a single tumor that grows larger and spreads to other parts of the liver.

2. Several small nodules are spread throughout the liver. This type of cancer is often seen in people with cirrhosis.

• Intrahepatic Cholangiocarcinoma (Bile Duct Cancer): It accounts for about 10% to 20% of hepatic cancers. These types of cancers start in the small bile duct within the liver.

• Angiosarcoma and Hemangiosarcoma: Cancers originate in the cells lining the liver's blood vessels. Populations exposed to vinyl chloride or thorium dioxide are more prone to such cancers.

• Hepatoblastoma: A very rare kind of cancer affecting children below the age of four years. The cells of hepatoblastoma are very similar to fetal liver cells.

• Secondary Liver Cancer: When cancer spreads into the liver from other sources of origin, it is known as secondary liver cancer.

Conclusion:

The malignancies affect parts of the digestive system except for the intestines as non-colorectal cancers. It can affect the pancreas, stomach, esophagus, and liver. The symptoms vary depending on the affected organ, but treating the condition on time is important as it may become fatal. Malignancy in any part of the digestive system can affect the entire process of digestion.