Gastrointestinal Cancer

Overview

The gastrointestinal tract (GI tract) begins with the esophagus (the tube that transports food from the mouth to the stomach) and ends with the anus (where waste exits the body). Primary GI cancer begins in the GI tract. Metastatic gastrointestinal malignancies begin in the gastrointestinal tract but spread to other regions of the body.

What is Gastrointestinal Cancer?

Gastrointestinal (GI) cancer refers to malignancies that affect the digestive system. This encompasses all of the cancers listed below.

• Esophageal Cancer
• Liver Cancer
• Stomach Cancer
• Gallbladder & Biliary Tract Cancer
• Pancreatic Cancer
• Gastro-Intestinal Stromal Tumor (GIST)
• Neuroendocrine Tumors (NETs)
• Colorectal Cancer
• Small Bowel Cancer
• Anal Cancer

The most frequent type of cancer, affecting both men and women, is gastrointestinal cancer. Every year, around 33,200 Australians are diagnosed with it, and 37 Australians die from it.

Esophageal Cancer (Carcinoma)

The esophagus is the tube that links the mouth, throat, and stomach ("food pipe"). When a person swallows, the muscular wall of the esophagus contracts, assisting in the movement of food down to the stomach. The esophagus can be affected by one of two forms of cancer. Squamous cell carcinoma is more typically found in the upper or intermediate esophagus. Adenocarcinoma develops in the lower esophagus.

Symptoms of Esophageal Cancer

Early-stage very tiny tumors do not usually produce symptoms. As the tumor becomes bigger and the esophagus narrows, patients frequently have trouble swallowing. Most people have difficulty swallowing solid things like meat, bread, or raw vegetables at first. As the tumor develops, the esophagus narrows, making it difficult to swallow even liquids. Indigestion, heartburn, vomiting, and choking can all be indications of esophageal cancer. Patients may also have coughing and hoarseness of voice. Weight loss that is not voluntary is also prevalent. Patients may vomit blood in rare cases.

Causes/Risk Factors

In most cases, the doctor will begin by obtaining a thorough history and completing a physical examination. Routine blood tests may detect anemia. Endoscopy is a procedure in which a thin flexible lit tool with a camera at the end is inserted via the mouth into the esophagus. The doctor may see the inner layer of the esophagus using this scope. If necessary, biopsies might be obtained during this process and sent to a pathologist for analysis under a microscope to detect cancer cells.

Diagnosis for Esophageal Cancer

In most cases, the doctor will begin by obtaining a thorough history and completing a physical examination. A barium swallow, commonly known as an esophagram, is a sequence of x-rays of the esophagus. The patient is given a barium solution to consume, which covers the interior of the esophagus. Following that, many x-rays are taken to examine for changes in the shape of the esophagus.

Endoscopy is a procedure in which a thin flexible lit tool with a camera at the end is inserted via the mouth into the esophagus. The doctor may see the inner layer of the esophagus using this scope. If necessary, biopsies might be obtained during this process and sent to a pathologist for analysis under a microscope to detect cancer cells.

A CT scan of the neck, chest, and abdomen may help establish if the cancer has spread to other organs in the body, allowing the doctor to select the best course of treatment.

Endoscopic ultrasonography is a method that may be used to determine the depth of a tumor as well as the involvement of nearby lymph nodes. This tool is identical to the endoscope, except that it has ultrasonic imbedded at the tip. Any questionable lymph nodes can be aspirated using a fine needle under ultrasound supervision.

Esophageal Cancer Treatment

Depending on the stage of the cancer, the patient may require surgery, radiation, and/or chemotherapy. Many individuals with esophageal cancer are treated with a combination of surgery, radiation, and chemotherapy.

Some patients with extremely early esophageal cancer may benefit from endoscopic resection without surgery, such as endoscopic mucosal resection or endoscopic submucosal dissection.

When the cancer cannot be entirely treated, alternative techniques to relieve symptoms may be used, such as stretching or dilatation, tube prosthesis (stent), and radiation or laser treatment to diminish the size of the tumor. Doctors are continually researching innovative drugs and therapy procedures in order to enhance treatment results and decrease adverse effects.

Stomach Cancer (Gastric Cancer)

The stomach is a digestive organ that links the esophagus to the small intestine. When food enters the stomach, the muscles of the stomach use a motion called peristalsis to help mix and mash the food. Stomach cancer can begin in any portion of the stomach and spread to other organs such as the small intestines, lymph nodes, liver, pancreas, and colon.

Gastric Cancer Symptoms

Patients may not have any symptoms in the early stages, and the diagnosis is frequently confirmed after the disease has progressed. The following are the most prevalent symptoms:

• Pain or discomfort in the abdomen
• Nausea and vomiting
• Loss of appetite
• Fatigue or weakness
• Bleeding (vomiting blood or passing blood in stools)
• Weight loss
• Early satiety (cannot eat a complete meal because of a “full feeling”)

Causes/Risk Factors

No one knows for certain what causes stomach cancer. Researchers have discovered that certain risk factors are linked to the development of stomach cancer. People over the age of 55 are more prone to get stomach cancer. Men are afflicted twice as often as women, and African Americans are more frequently impacted than Caucasians.

Screening/Diagnosis

Your doctor may do one or more of the following tests in addition to getting a comprehensive history and completing a physical exam:

• Upper GI series – The patient is instructed to consume a barium solution. Following that, x-rays of the stomach are taken. The barium outlines the inside of the stomach, revealing any abnormal spots that might be cancerous. This test is utilized less often than it once was, and patients are now more likely to have endoscopy first.
• Endoscopy – An endoscope is a lighted, flexible tube with a camera that is put from the mouth into the esophagus and subsequently into the stomach. Sedation is administered prior to the insertion of the endoscope. Biopsies (tissue samples) can be obtained and studied under a microscope if an abnormal region is discovered.

If cancer is discovered, the doctor may order more staging tests to see if the disease has spread. A CT scan can help establish whether cancer has progressed to the liver, pancreas, lungs, or other organs around the stomach.

Endoscopic ultrasonography can also be used for gastric cancer staging. Endoscopic ultrasonography can assist detect the depth of the tumor's progress into the stomach wall and the involvement of surrounding organs, as well as any enlarged lymph nodes that may be infiltrated with cancer cells.

Gastric Cancer Treatment

Treatment plans may differ based on the tumor's size, location, and extent, as well as the patient's general health. Surgery, chemotherapy, and/or radiation therapy are all options for treatment.

The most frequent therapy is surgery. The surgeon might remove a portion of the stomach or the complete stomach (gastrectomy). During surgery, lymph nodes around the tumor are usually removed to be examined for cancer cells.

Chemotherapy is being studied before surgery to help decrease the tumor and after surgery to help kill leftover tumor cells. Chemotherapy is administered in cycles that last several weeks depending on the medications employed.

Radiation treatment is the use of high-energy radiation to destroy cancer cells and prevent their growth. Radiation only kills cancer cells in the treated region.

Some individuals with extremely early stomach cancer that only affects the superficial layers of the stomach wall may benefit from endoscopic excision of the malignancy without surgery utilizing procedures such as endoscopic mucosal resection or endoscopic submucosal dissection.

Doctors are experimenting with several combinations of surgery, chemotherapy, and radiation therapy to discover which one will be most effective.

Liver Cancer (Hepatocellular Carcinoma)

The liver is one of the body's major organs, located in the upper right quadrant of the belly. The liver performs several vital activities, including removing toxins from the blood, metabolizing medications, producing blood proteins, and producing bile, which aids digestion. Hepatocellular carcinoma is a kind of cancer that develops in the liver. Hepatoma is another term for primary liver cancer. Hepatocellular Carcinoma (HCC) is the world's fifth most frequent cancer.

HCC is growing more frequent in the United States. The source of this increase is likely to be chronic hepatitis C, an illness that can lead to HCC. The majority of malignancies identified in the liver in the United States spread or metastasis from other organs. These are not HCC malignancies, as HCC cancers develop in the cells of the liver. The most prevalent cancers to metastasis to the liver include colon, pancreatic, lung, and breast cancer.

Liver Cancer Symptoms

The most frequent symptom of HCC is abdominal discomfort, which generally occurs when the tumor is quite big or has progressed. In people with cirrhosis, unexplained weight loss or fevers are warning indications. Acute abdominal swelling (ascites), yellow coloring of the eyes and skin (jaundice), or muscular atrophy all point to HCC.

Causes/Risk Factors

Individuals infected with the hepatitis B and/or hepatitis C viruses are at a higher risk of developing HCC. Alcohol-related liver illness is another risk factor for HCC development.

Certain substances have been linked to liver cancer, including aflatoxin B1, vinyl chloride, and thorotrast. Aflatoxin is produced by the mold Aspergillus flavus and can be found in foods including peanuts, rice, soybeans, corn, and wheat. In addition, thorotrast is no longer utilized in radiologic testing, and vinyl chloride is a chemical present in plastics.

Hemochromatosis, a disorder characterized by improper iron metabolism, is closely linked to liver cancer. Cirrhosis from any cause, including the hepatitis virus, hemochromatosis, and alpha-1-antitrypsin deficiency, increases the likelihood of developing HCC.

Screening/Diagnosis

Routine blood tests cannot be used to diagnose HCC. A blood test for the tumor marker alpha-fetoprotein (AFP) and radiological imaging are required. In order to detect tiny HCC, some clinicians recommend measuring AFP and imaging every 6 to 12 months in patients with cirrhosis. Sixty percent of HCC patients will have increased AFP levels, whereas the balance may have normal AFP levels. As a result, a normal AFP level does not rule out HCC.

Ultrasound, CT scan MRI, and angiography are all examples of radiological imaging investigations that are highly essential.

If HCC is suspected, an ultrasound examination of the liver is routinely performed. In the United States, CT scans are commonly used to diagnose liver tumors. A multi-phase CT scan with oral and IV contrast is the best investigation. MRI may offer cross-sectional pictures of the body in various planes. MRI can really recreate pictures of the biliary tree as well as the liver's arteries and veins.

Angiography is a test that involves injecting contrast material into a major artery in the groin. The arterial blood flow to the liver is then assessed using X-ray images. If the patient has HCC, the newly generated aberrant tiny blood arteries that feed the tumor create a distinct pattern.

In individuals with a risk factor for HCC and increased AFP, a biopsy may not be necessary. Biopsy can be conducted if the diagnosis of HCC is in doubt or if the clinician believes the biopsy results will influence the course of treatment.

Liver Cancer Treatment

The prognosis is determined on the tumor's stage and the severity of the underlying liver illness. Certain indicators indicate a poor outcome. These are some examples:

• Demographics: male gender, older age, alcohol consumption
• Symptoms: weight loss, decreased appetite
• Signs of impaired liver function: jaundice, ascites or mental confusion related to liver disease (encephalopathy)
• Blood tests: elevated liver tests, low albumin, high AFP, low sodium, high blood urea nitrogen
• Staging of tumor: tumor over 3 cm, multiple tumors, tumor invasion of local blood vessels, tumor spread outside of liver.

Chemotherapy:

This might entail injecting anti-cancer drugs into the body via a vein or chemoembolization. Chemoembolization is a method in which chemotherapy medications are injected directly into the blood arteries that supply the tumor and tiny blood vessels are closed to keep the drug within the tumor. Chemotherapy might alleviate symptoms and perhaps reduce tumor growth (in 50% of patients), but it is not curative.

Ablation:

Other therapeutic possibilities include ablation (tissue destruction) therapy utilizing radiofrequency waves, alcohol injection into the tumor, or proton beam radiation to the tumor location. There is no evidence that one of these treatments is superior to another.

Surgery:

Only individuals with excellent liver function and tumors smaller than 3-5 cm in size that are confined to the liver are candidates for surgery. If the procedure is successful, the patient's five-year survival rate is 30-40%. Many people may develop HCC in another area of the liver.

Liver Transplantation:

Patients with end-stage liver disease and minor HCC may benefit from liver transplantation. However, there is a major donor shortage in the United States.

Pancreatic Cancer

The pancreas produces pancreatic secretions, which aid in digestion in the small intestines, as well as hormones such as insulin. It is placed in the rear of the abdomen, behind the stomach. The pancreatic duct enters the first segment of the small intestine (called the duodenum) via a nipple-like hole called the ampulla.

Pancreatic Cancer Symptoms

Because early pancreatic cancer seldom causes symptoms, it is regarded as the "silent" illness. As the tumor grows in size, the patient may experience one or more of the following symptoms:

• Jaundice – If the tumor covers the bile ducts (the main bile duct runs via the pancreas), the patient may develop jaundice, a disease in which the skin and eyes get yellow and the urine turns black.
• Abdominal pain – As the cancer grows, the patient may have pain in the abdomen which may radiate to the back. Pain may increase with eating or lying down.
• Nausea
• Decreased appetite
• Weight loss

Causes/Risk Factors

It is unknown why some people get pancreatic cancer. According to research, some risk factors enhance the likelihood of developing pancreatic cancer. Tobacco use is a risk factor. Alcohol use, a high-fat diet, and chronic pancreatitis may also be risk factors. People who have hereditary pancreatitis are also more likely to get pancreatic cancer. A family history of pancreatic cancer, as well as some hereditary and genetic disorders, are all crucial risk factors.

Screening/Diagnosis

The doctor may do endoscopic and radiologic tests such as a CT scan, MRI, or ultrasound in addition to collecting a comprehensive history and completing a physical examination. Endoscopic ultrasonography can also be used. This test may aid in the detection of tiny cancers that are less than 2-3 cm in size (one inch). In some situations, a biopsy of an aberrant region of the pancreas may be done by introducing a needle into the pancreatic under ultrasonic guidance.

A unique x-ray scan of the pancreatic duct and the common bile duct, known as an endoscopic retrograde cholangiopancreatogram (ERCP), may also be utilized to make the diagnosis. A flexible tube with a light and camera at the end is introduced via the mouth into the stomach and then the small intestines for this test. Sedation is administered. A dye is then injected into the pancreatic and bile ducts to examine for aberrant filling or tumor occlusion of these channels. Biopsies can be obtained using a brush placed into the bile duct during this operation. After that, the biopsy specimens are analyzed under a microscope for cancer cells.

Pancreatic Cancer Treatment

Pancreatic cancer is only treatable if discovered in its early stages. Treatment options include surgery, radiation, and chemotherapy. If necessary, surgery may be performed to remove all or part of the pancreas and surrounding structures. Radiation treatment can be used to destroy cancer cells and stop their growth. Radiation may be administered after surgery in certain trials to help eliminate any leftover cancer cells. 

Although chemotherapy will not cure pancreatic cancer, it may decrease the tumor's development or enhance the patient's quality of life. Many novel medications are being researched for pancreatic cancer chemotherapy, and individuals with this condition may be able to participate in one of the research studies for pancreatic cancer chemotherapeutic treatment.

Pain management may be problematic in pancreatic cancer patients. Patients may be given pain medication or sent for a nerve block, which is performed by injecting alcohol into the bundle of nerves around the pancreas to reduce pain signals from the pancreatic cancer to the brain.

Colon cancer

Colon cancer develops when abnormal cells in the large intestine wall proliferate uncontrollably. Any cancer that begins in the large intestine is referred to as bowel cancer. Depending on where it is diagnosed in the gut, it is also known as colon cancer, rectal cancer, or colorectal cancer.

How does Bowel Cancer develop?

Bowel cancer is caused by gene mutations that cause large intestine cells to proliferate abnormally and develop polyps. Most intestinal polyps are not malignant, however if left untreated, certain polyps might develop into tumors.

Colorectal cancer most usually occurs in the lower descending colon, also known as the sigmoid colon or rectum. A sign is a visual or tactile display that may be seen or felt by others. In certain circumstances, bowel cancer manifests as a tumor or lump in the belly or rectum, which can be identified during a doctor's examination.

What are the common general signs and symptoms of Bowel Cancer?

It is crucial to remember that many of the signs and symptoms of bowel cancer are also linked with other illnesses and disorders and may not necessarily suggest bowel cancer. Early bowel cancer may not cause any symptoms. As the tumor develops or multiplies, it may cause one or more of the following symptoms.

• Rectal bleeding or blood in the stool
• Change in bowel habits, either having more bowel, smaller movements; more constipation (Any noticeable change from what is normal and regular)
• A change in stool appearance or consistency such mucus in the stools or narrower stools
• Diarrhea or constipation that lasts more than several days
• Gas, bloating or cramps in the bowel or rectum
• A feeling of fullness in the bowel even after a bowel movement
• A pain or lump in the rectum or bowel

Fatigue, weakness, and unintentional weight loss are possible symptoms. Many of the symptoms associated with colon cancer might also be caused by other disorders, such as IBS. Some of these symptoms can also be caused by certain drugs and diets. Any changes or symptoms should be discussed with a doctor.

Bowel Cancer treatment

Treatment is determined by the size of the tumor, the depth to which the cancer has entered the layers of the colon or rectum, and if the cancer has spread to other organs such as the liver or lymph nodes. If the cancer is restricted to a polyp, a colonoscopy to remove it may be enough to cure the condition.

If surgery is required, the following therapies are available, depending on the stage and location of the cancer:

• Neo-adjuvant radiation and/or chemotherapy: This treatment is frequently administered prior to surgery. It causes cancer cells to shrink and die, making surgical treatments easier and more likely to succeed.
• Adjuvant chemotherapy and/or radiotherapy: Treatment administered following surgery to eliminate any leftover cancer cells in the body.

If the cancer has advanced to the colon, a surgeon may do a hemi-colectomy, which involves removing a piece of the bowel as well as adjacent lymph nodes. Because of developments in laparoscopic technology and fiber optics, surgeons may often conduct treatments with minimal incisions, reducing patient suffering and recovery time.

Surgery may be more difficult if the malignancy is in the rectum. Just like a lumpectomy for breast cancer removes as little good breast tissue as possible, tiny tumours in the rectum may be treated locally if they haven't grown through the gut wall. If the cancer has progressed to the lymph nodes or has grown through the rectum wall, more invasive surgery may be necessary.

Conclusion 

Cancer that originates along the GI system is known as gastrointestinal cancer (also called the digestive tract). The type of cancer, the stage of development, and other health issues will all influence treatment. Surgery, chemotherapy, and radiation therapy are popular treatments.