What is colorectal cancer?
It is also known as colon cancer or rectal cancer. It refers to any cancer found in the colon. It occurs when cells lining the inside of the colon become abnormal and grow uncontrollably. It begins with when small tissue growths, called polyps, appear and develop into cancerous lesions unless detected and treated in a timely manner.
A portion of patients develop colorectal cancer sporadically, without any previous family history of cancer. However, there is a strong hereditary predisposition for individuals whose parents had colon cancer to develop the disease at earlier ages.
What are the symptoms?
A large number of patients with colorectal cancer do not experience any symptoms in the early stages of the disease. In fact, it often goes unnoticed until it has reached advanced stages. For this reason, routine screening and awareness of risk factors are extremely important. Because many of the symptoms of colon cancer also appear in a variety of other colon diseases, it is important to consult a specialist in endoscopy to conduct studies and achieve timely detection.
Some symptoms can appear in isolation or together, and they include:
- Blood in feces
- Diarrhea not resulting from disease or diet
- Long-term constipation
- Abdominal pain or cramps
- Changes in bowel movements
- Persistent decrease in the size of feces
- Frequent sensation of bloating
- Weight loss with no known cause
In its initial phases, patients tend to present no symptoms.
How is the diagnosis made? The ideal form of detection is to undergo a colonoscopy. Arising lesions found during the examination can be removed at that moment. In previous times, rectal exam and a search for blood in feces were performed as part of diagnosis; however, these may present an incomplete picture, particularly in patients who may present no symptoms until late stages of the disease.
What is a colonoscopy?
It is an visual examination of the rectum and colon performed by introducing a flexible tube with a special camera attached to the end through the anus. This allows the physician to observe the interior of the colon to search for abnormalities and identify any polyps or rising cancer.
The patient must undergo special preparation comprised of a liquid diet, enema, and laxatives to allow for a clean colon and good visibility at the time of examination. Any polyps found can be removed without the need of surgery. In case of finding a tumor, a biopsy can be obtained and removed through the working channel of the colonoscope, allowing the physician to obtain a small tissue sample of the area for further examination under the microscope. Generally the procedure is performed at an outpatient clinic with the use of a sedative. Patients sleep during the procedure and feel little to no discomfort. Occasionally, air that is introduced into the colon during the procedure may cause cramps temporarily at the end.
How is colorectal cancer prevented?
The only way of preventing this fatal disease is by performing a screening colonoscopy that may lead to detection of polyps. International guidelines recommend that all individuals over the age of 50 should undergo a screening colonoscopy. Our experience has allowed us to find polyps in patients as young as 45. Sons or daughters of individuals with colon cancer should undergo the examination at earlier ages.
How is colorectal cancer treated?
Resection of benign or malign polyps during colonoscopy: Polyps can be removed at the time of the screening procedure through a technique called polypectomy.
Once the polyp is extracted, it is sent to be examined under the microscope to determine it malignancy or the presence of cancer. It is possible to remove a malignant polyp and leave behind only healthy tissue, effectively avoiding a possible cancer from spreading.
Endoscopic Submucosal Dissection (ESD):
In case of finding flat cancerous lesions with minimum depth and no invasion to deep layers of the colon, it is possible to perform a minimally invasive surgery called Endoscopic Submucosal Dissection. With the use of electrosurgical tools and high-quality accessories, it is possible to remove the lesions without the need for invasive surgeries, minimizing the length of hospital stay and recovery periods.
The purpose is to completely eliminate the invasive cancer, relieve the symptoms, and offer a better opportunity of healing. Candidates for surgery undergo preparatory examinations to discard the possibility of invasion to other organs, which include barium opaque enema, endoscopic ultrasound (EUS), CT scan, x-rays, and blood work testing for specific cancer antigens, depending on the location of the tumor. It’s important to note that earlier detection least to less invasive treatments and higher chance of definitive cure.