When a patient starts experiencing colon cancer symptoms, they must immediately see a doctor for a proper evaluation. The doctor may begin with a physical examination and medical history assessment before any test in order to understand the causes of the symptoms.
If the colon cancer diagnosis is confirmed, the doctor may further proceed with staging. Upon obtaining crucial information like the type of colon cancer, its stage, its grade, its exact location, and the patient’s overall health status, the doctor, along with their team, will devise a personalized colon cancer treatment plan.
Oncologists are often asked about how to detect colon cancer at home or through self-tests. It is not possible to detect colon cancer at home, as it requires a battery of specialized tests to be diagnosed accurately. The following are the most recommended tests for colon cancer diagnosis:
The doctor may advise the patients to undergo fecal occult blood tests to determine the presence of blood in the stool. This is because the blood vessels in the cancerous tumor are generally fragile and easily damaged during stool passage.
The test is also called a multi-targeted stool DNA test. It allows the doctors to determine the abnormalities in the DNA of the cancerous cells. The test also identifies the hidden blood in the stools.
This test is performed with the assistance of a colonoscope. The colonoscope comprises a thin, long tube for easy insertion into the anus, with a camera and light source to view the internal tissues of the colon.
Colonoscopy is a method to visualize the internal tissues of the colon with a colonoscope to detect the presence of abnormal cells or polyps. However, in some cases, the doctors may need to collect the samples after visualizing the abnormal tissues or polyps for further examination (biopsy). In such cases, specialized instruments are inserted through the colonoscope to obtain the samples.
Sigmoidoscopy is a colon cancer test performed with the help of a sigmoidoscope. It is similar to a colonoscope (a thin tube with a camera at the tip). Unlike colonoscopy, which involves the examination of the entire colon, sigmoidoscopy examines only the lower colon.
This test is useful for patients who do not wish to undergo more uncomfortable procedures for colon examination, such as colonoscopy. Virtual colonoscopy involves using computed tomography to detect polyps or abnormal areas of the colon. Further, a colonoscopy is required after a virtual colonoscopy to obtain the tissue samples.
A CT scan is an imaging technique employed to develop high-quality images of the colon with the help of X-rays. Apart from detecting abnormal cells in the colon, the test also determines the spread of cancer to nearby lymph nodes or distant organs, such as the lungs or liver.
Magnetic resonance imaging gives clear images of the colon using strong magnets and radio waves. The doctor may inject a contrast agent, such as gadolinium, to get clearer images before the MRI. MRI may also detect the spread of colon cancer to distant organs, e.g., the liver, brain, or spinal cord.
Unlike other imaging techniques, such as CT and MRI, that provide morphological and anatomical structures of the target site, a PET scan gives detailed information about the metabolism of the tumor. It assists oncologists in differentiating between malignant and benign tumors. The PET scan also helps in staging colon cancer by determining the spread of the tumor to nearby and distant areas.
Once the diagnosis is confirmed, the disease has to be staged to understand the extent of its spread. Based on the information obtained through staging, the doctors devise a customized treatment plan for each case. While staging, various factors, such as tumor size, depth of invasion into the colon wall, lymph node involvement, and the presence of distant metastases, are taken into consideration. Stage 0, stage 1, stage 2, stage 3, and stage 4 are the different stages of colon cancer.
Samples obtained through colonoscopy are sent for a comprehensive laboratory examination. The tissue samples are analyzed under the microscope to determine the presence of cancerous cells.
Genetic testing is also performed on the samples obtained during the biopsy. Genetic testing helps determine the type of gene mutation that has led to the formation of cancer. It is often recommended for patients with advanced colon cancer to identify specific gene mutations to determine their eligibility for targeted therapy.
Once the screening or diagnostic testing is complete, the doctor consults with the patient and provides an appropriate treatment plan. If the patient is diagnosed with polyps, usually no medication is prescribed.
However, the patient may be advised to undergo scheduled monitoring to constantly check if the polyps have developed into colon cancer.
The colon cancer treatment plan is created after considering a myriad of factors, starting from the type of cancer, its stage, and grade to the overall health of the patient. Some of the colon cancer treatment options include:
Surgery is the preferred treatment for early-stage colon cancer. The primary goal of surgery is to remove the tumor. Colon cancer surgery may or may not be followed by other treatments like chemotherapy and radiation therapy.
Polypectomy is a type of colon cancer surgery to remove early-stage colon cancer (stage 1 colon cancer treatment) and polyps. Polypectomy involves the removal of the polyps from the base of the polyps by inserting a wire loop into the colonoscope and passing an electric current through the wire.
Laparoscopic surgery for colon cancer is a minimally invasive procedure for removing the cancerous tissues from the colon. Unlike conventional open colon cancer surgery, laparoscopic surgery involves making small incisions in the abdomen to remove the cancerous tissues. During laparoscopic surgery, the surgeon may also obtain samples of nearby lymph nodes to detect the spread of cancer outside the colon.
Colectomy involves the removal of the colon, partially or completely. If the colon is removed partially, the procedure is known as a partial colectomy, hemicolectomy, or segmental resection. If the colon is completely removed, the procedure is known as a total colectomy. Colectomy is considered an effective cure for colon cancer if the disease is limited to the colon.
Sometimes, the surgeon may remove the nearby lymph nodes to check for cancer. It will help in staging the disease and narrowing the optimal treatment options.
A colostomy is a procedure to form an opening of the colon onto the abdomen to pass stool. It is done when there is a need for intestinal removal, such as in colon, rectal, or anal cancer. An ileostomy is a procedure that involves opening the ileum into the abdomen.
Chemotherapy for colon cancer involves using medications that kill rapidly dividing cells, including colon cancer cells. Chemotherapy is usually prescribed as a combination of various drugs. The delivery of drugs is through the oral or injectable route. Chemotherapy may be administered before the surgery (neoadjuvant chemotherapy) or after the surgery (adjuvant chemotherapy).
Targeted therapy is one of the newer colon cancer treatments. Certain cellular components and pathways are specific to cancer cells, and they are vital for the growth, division, and spread of cancer. Targeted therapy targets those specific molecules and cellular pathways and interferes with the growth, cell division, and proliferation of cancerous cells.
Immunotherapy delivers the drugs that stimulate the immune system to damage the cancerous cells. Drugs delivered under immunotherapy interfere with the processes through which the cancer cells hide from the immune system, thus making them more vulnerable to being attacked by the immune cells.
In radiation therapy for colon cancer, specialists guide high-energy radiation toward the tumor, damaging the cancerous cells. Radiation therapy is usually used in combination with chemotherapy or surgery.
Adjuvant therapy for colon cancer may also be prescribed. As an adjuvant therapy, chemotherapy destroys residual cancer cells after surgery. Another adjuvant therapy for colon cancer is embolization or ablation of the cancer.
Palliative care is recommended for patients with advanced-stage colon cancer. Palliative care aims to manage cancer symptoms and improve the patient's quality of life.
Patients who do not show a desirable response to the standard colon cancer treatments may register themselves in clinical trials where they can access new drugs and treatments whose efficacy is yet to be understood.
Patients must know that the clinical trial team prioritizes patient safety and that they are closely monitored throughout the study.
Lastly, clinical trials are not suitable for all patients. The eligibility criteria may vary depending on the objective of the trial and other parameters. Those patients who are interested in enrolling in clinical trials should have a detailed discussion with their expert team.
HCG is one of the leading comprehensive cancer treatment hospitals in India, with all the facilities available for effectively diagnosing and treating colon cancer. The center is equipped with advanced diagnostic facilities that assist oncologists with accurate colon cancer diagnoses. As one of the best colon cancer treatment hospitals in India, HCG houses advanced treatment facilities to administer modern treatments like immunotherapy, targeted therapy, and minimally invasive surgeries as a part of colon cancer treatment.
Several screening and diagnostic tests are available for colon cancer diagnosis. Those who already have polyps will need monitoring, as these tend to become cancerous over time. Those identified as high-risk individuals need to pay extra attention to their health and opt for regular screening to reduce their overall colon cancer risk.
As far as treatment is concerned, oncologists devise colon cancer treatment based on stage, grade, the exact location of the tumor, and the overall health status of the patient. While early-stage cancers can be treated effectively with less complex treatment plans, stage 2 colon cancer treatment, stage 3 colon cancer treatment, and stage 4 colon cancer treatment include a combination of various treatments.