Rectal Cancer

Overview

Rectal cancer is a kind of cancer that is found in the rectum of the large intestine. It begins as polyps that may turn cancerous at some time in future without chemotherapy. Some of the most common signs are faecal bleeding, alterations of bowel movement, and stomach aches. It can happen because of age, family history, inflammatory bowel diseases and consumption of red and processed meats.

Screening examinations such as colonoscopies are vital in early identification that will increase survival rates. The most common remedies used for treating the disease are surgery, radiation therapy or chemotherapy, depending on the stage. When the disease is detected early and adequate measures are taken it is possible to successfully treat rectal cancer.

What is Rectal Cancer?

Rectal cancer is a cancer that occurs in the rectum, the last section of the large intestine. It starts with abnormal growths known as polyps and may turn malignant later in life. One will find blood in the stool, changes in bowel habits, pain and cramping, and loss of weight as prominent signs of rectal cancer.

Risk factors of colon cancer include age, family history, inflammatory bowel disease, and a diet that includes red and processed meat. Furthermore, screening tests like colonoscopy if done for early advanced-stage diseases have better chances of being cured. Surgical operation, radiotherapy, chemotherapy and molecular targeted therapy are the treatments offered depending on the cancer stage and location.

Types of Rectal Cancer

The two main ways in which rectal cancer is staged are based on the originating cell type and the location within the rectum. The most common types include:

Adenocarcinoma

Adenocarcinoma is the most frequent histological diagnosis of rectal cancer and constitutes approximately 95% of the cases. It begins in the epithelial tissue of the rectum and secretes mucus which is characteristic of gland cells. Moreover, they are usually slow-growing and can easily metastasise to other organs of the body if diagnosed late.

Neuroendocrine Tumours

Neuroendocrine tumours (NETs) are rare and arise from hormone-secreting cells of the rectosigmoid colon. This can be either noncancerous or cancerous with the latter possibly forming in other organs. Most of the time the symptoms are pretty much like in many other diseases related to digestion, this is why they are so easy to overlook.

Squamous Cell Carcinoma

This type of cancer starts in the flat cells that line the rectum and is a rare form of cancer. Squamous cell carcinoma is pretty common in those who develop some specific risk factors. These factors include chronic inflammation, HPV infection or immunosuppression.

Gastrointestinal Stromal Tumors (GISTs)

GISTs are a rare histological type of rectal cancer originating from the interstitial cells of the gastrointestinal tract. Most of them are not cancerous but sometimes, can turn invasive and spread to other parts of the body and hence needs specific treatment methods.

Symptoms of Rectal Cancer

The signs of rectal cancer can be ambiguous and may be related to tumour size, cancer stage, and location. It can be asymptomatic in the early stages and therefore it is advisable to undergo a colonoscopy after consulting with a doctor. Moreover, some of the symptoms arise when the cancer is in its advanced stage. They include the passing of blood in stool and blood-stained toilet paper. Diarrhoea, constipation or the feeling that the bowel has not been emptied adequately is also present frequently.

Other symptoms include loss of appetite, continuous stomach ache, tiredness, and exhaustion. However, some people may develop a sensation of fullness and pressure in the rectum which is a sign of bowel obstruction. When cancer has reached the later stages, then the individual has symptoms such as pale skin and shortness of breath due to anaemia. These symptoms must be brought to the immediate attention of a healthcare provider as they could be a sign of rectal cancer or other colorectal complications. Moreover, if there are signs of the disease at a preliminary stage it is easier to cure it.

Causes of Rectal Cancer

The causes of rectal cancer itself have not been determined completely but there are some factors which can be considered as causes of this disease. This makes age one of the biggest risk factors because most people who develop this condition are above 50 years of age. Furthermore, significant genetic history is very important as the genetic component shows that if any first-degree relative of the person has colorectal cancer, the risk is high. There are many primary acquired risk factors some of which include Lynch syndrome and Familial Adenomatous Polyposis (FAP).

Since inflammations in the rectum are long-term inflammations brought by conditions such as ulcerative colitis or Crohn’s disease, people diagnosed with these conditions are at a higher risk of receiving the ingredient. Also, consuming high-red or processed meat and low-fibre diets may cause cancer because the colon’s cells are modified. Some other risk factors include being obese, smoking, and heavy drinking of alcohol. Furthermore, the lack of physical activity like sitting for long periods is also causing the incidence to rise.

Rectal Cancer Diagnosis and Tests

When a person is suspected to have rectal cancer some immediate tests need to be carried out. The first test is a Digital Rectal Examination (DRE) in which a doctor feels for any lumps or changes in the rectal area. When such investigations are completed, a colonoscopy is normally recommended for the patient. In a colonoscopy, a thin tube with a camera is passed through the rectum and into the colon to look for signs of cancer and small samples of the tissue lining may be taken for a biopsy.

If a colonoscopy cannot be done, a flexible sigmoidoscopy can be used to look only at the colon and rectum. A CT scan, MRI or PET scan involve imaging to evaluate the size and location of the cancer. Also, for the tumour markers, there are blood tests like the Carcinoembryonic Antigen (CEA) test. Screening with these techniques should be done as early as possible to factor in treatment.

Rectal Cancer Management and Treatment

The medical therapy for rectal cancer is different for individuals and depends on the stage of cancer, its location, and the overall health of the patient. The conventional forms of treatment encompass operation, radiation therapy, chemotherapy, and new way therapies. Initial treatment can be surgical, using options from simple tumour removal to total mesorectal excision. This procedure involves the complete removal of the rectum and its surrounding tissue. In the more severe Stage 4 cancers, targeted therapies, or immunotherapies are often used. These therapies target specific mechanisms of cancer cells or the use of the body’s immune system to contain the cancer.

Preventive Measures of Rectal Cancer

The prevention of rectal cancer includes changing specific behaviours and practising early screening. One of the main preventive measures includes maintaining a proper diet, especially consuming foods containing fruits, vegetables and whole-starch foods that contain fibre. Also, reducing the consumption of red and processed meats is recommended since they are associated with colorectal cancer. It may also help to avoid being physically inactive and to keep to a healthy weight.

Tobacco should not be consumed and stopped altogether. Also, alcohol intake should be limited because it is identified as a risk factor for rectal cancer. People with other risks for getting the disease like a family history of colorectal cancer or Lynch syndrome are encouraged to seek genetic counselling and get colonoscopies more often and at a younger age.

Myths and Facts Related to Rectal Cancer

Here are some of the most common myths and facts related to rectal cancer:

Myth 1: Rectal Cancer is Only Seen in Older Individuals
Fact: Age is one of the strongest indicators, but rectal cancer can develop in millennials. This is because they can have a family history or other inherited conditions, such as Lynch syndrome.

Myth 2: If You Have No Symptoms of Rectal Cancer No Screening is Required
Fact: In some cases, rectal cancer in its early stage does not manifest any signs and symptoms. Therefore, screenings that include a colonoscopy are important for all people over the age of 50. That is why recognising the disease in its early stage is very effective in treatment.

Myth 3: Dietary Fibres Possess the Ability to Cure Rectal Cancer
Fact: Although people whose diet is high in fibre are less likely to develop rectal cancer, a fibre-packed diet does not cure this disease. The usual approach to most cancers is surgical, with subsequent chemotherapy, and at times radiation.