The large intestine contains two parts, the rectum, and the colon. The rectum forms a connection between colon and anus. It is present in the last six inches of the large intestine. Rectal cancer occurs when cells of the area grow abnormally.
The lack of proper registration systems often makes it difficult to analyse separate demographics data of rectal cancer. Most of the researches combines rectal and colon cancer. However, according to a research study over five years, few statistical figures were obtained. In Nigeria, which is one of the largest countries in Africa, 24 patients of colorectal cancer are diagnosed every year. Females have a higher chance of developing the disease. The ration between males and females was 1: 1.14. About 71.7% of patients have rectal cancer. Patients above the age of 40 years have a higher chance of rectum cancer. About 24% of the patient was below forty years of age.
Types of Rectal cancer
The majority of the people who have rectal cancer usually have adenocarcinoma. There are other rare types of rectal cancer as well. These rare types may be treated differently from adenocarcinomas.
Adenocarcinomas
It is the most common type of rectal cancer. Adenocarcinoma exists in the cells that are present on the inner lining of the rectum.
Carcinoid tumours
This type of rectal cancer exists in the cells responsible for producing hormones.
Gastrointestinal Stromal Tumours
Gastrointestinal stromal tumours affect the soft tissues of the rectum. It is found in different locations of the gastrointestinal tract. These tumors start from the blood vessels in the rectum.
Lymphoma
As the name indicates, lymphoma is a type of rectal cancer that is present in the lymph nodes of the region.
Hereditary Rectal Cancer
This type of rectal cancer exists in 5 to 10% of the population. The mutation of the genes is the primary causative factor in such cases. Certain tests may help to identify whether a person has hereditary genes of rectal cancer.
Symptoms of Rectal Cancer
The majority of the rectal cancers have no symptoms, which is why it remains undetected during routine physical examinations. However, certain alarming signs may indicate the progression of rectal cancer. This is as follows;
- The patient may suffer from changes in bowel habits. Furthermore, the patient can suffer either from diarrhea or from constipation.
- There may be blood in the stool. The color of the blood is usually dark red.
- There may be the presence of mucus in stool. This may only be visible in the stool examination test.
- There may be a change in the consistency of stool as well, which means that there may be loose or narrow stools.
- Some patients may suffer from constant pain in the abdomen. This pain may even occur when passing stool.
- The patients may also suffer from iron–deficient anemia.
- Weight loss occurs without any reason.
- The patient may feel weak.
- Some patients feel that the bowel is not empty.
Causes/Risk factors of Rectal cancer
The primary reason for the development of rectal cancer is the abnormality in the genes. However, these abnormalities are still not clear. Some of the probable causes of rectal cancer are as follows;
Inherited Gene Mutations
Gene mutations usually run in the family history. If a person in the family has rectal cancer, then this increases the chance.
Hereditary nonpolyposis colorectal cancer (HNPCC)
Lynch syndrome is the other name of Hereditarynonpolyposis colorectal cancer. This disease increases the risk of developing rectal cancer. People who suffer from this disease have rectal cancer before the age of 50.
Familial adenomatous polyposis (FAP)
This is a rare disorder of the polyps. In such cases, polyps develop abnormally in thousands of numbers in the rectum. People who do not treat FAP have a higher chance of developing rectal cancer before 40.
Diagnosis
Doctors usually identify rectal cancer after the identification of symptoms. However, people who have early-stage of rectal cancer. That’s why doctors recommend regular screening tests. People with an early diagnosis have a better outcome of the disease.
Physical examination and Familial history
The doctor may start by examining your symptoms. Familial history is also an essential aspect of diagnosis. It helps to establish if the patient has a chance of developing rectal cancer. After this initial step, a series of diagnostics tests may follow.
Colonoscopy and biopsy
A doctor suggests colonoscopy if he suspects a chance of developing rectal cancer. In a colonoscopy, a camera is inserted in the large intestine. The instruments remove a portion of the large intestine tissue. A lab analyses this tissue sample microscopically.
Diagnostic Imaging Tests
CT and MRI are the two diagnostic imaging tests. These help to identify if cancer has spread to other parts of the body.
Genetic Testing
This testing helps to identify genetic mutations. Furthermore, it helps to identify predisposition towards rectal cancer.
Complete Blood Count (CBC)
Anaemia is a symptom of Rectal cancer. A complete analysis of the blood helps to identify if the person is suffering from anemia. Furthermore, a high level of white blood cell helps to identify if the person has a tumor growth.
Staging
Diagnostic tests help to figure out the stage of rectal cancer. These stages are from 0 to 4. Details of the stages of rectal cancer are as follows
Stage 0
This is the initial stage of rectal cancer. Cancer of this stage does not spread far from the lining of the stomach.
Stage 1
At this stage, the tumors extend to the mucosal lining of the rectum. In some cases, it may penetrate the wall of the rectum.
Stage 2
At this stage, the tumor extends in the wall of the rectum. It may progress towards the tissues of the rectum.
Stage 3
At this stage, the rectum invades the lymph nodes. Furthermore, it may invade the structure and the tissues around the wall of the rectum.
Stage 4
The most advanced stage of rectum cancer. At this stage, the tumor spread to nearby organs near the rectum.
Treatment
If the clinicians diagnose and treat this cancer early, then it is completely treatable. With the progression of the stage, it may become difficult to treat it. In such cases, a combination of treatments helps to provide a progressive approach.
Surgical Approaches
It is the most treatment approach in most cases of rectal cancer. Doctors may combine it with radiation or chemotherapy to help shrink the tumor. However, this may not be suitable if cancer spreads to other regions.
Radiation Therapy
Radiation therapy helps to shrink the tumor. The doctors may perform radiation therapy before surgery. It helps in easy removal of the tumor.
Chemotherapy
Chemotherapy is often used in combination with radiation therapy or surgery. In this treatment method, the doctors inject chemotherapeutic drugs into the body. It helps to destroy the mutated cells. However, these have some serious side effects.
Palliative Care
This care helps the patient and provides them comfort. It helps in relieving pain. Furthermore, it also helps to relieve blockages in the rectum. It helps to improve the outlook of the surgery.
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