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Colorectal cancer is a disease where cells in the colon or rectum grow uncontrollably, forming a tumor. The colon is the longest part of the large intestine and helps absorb water and nutrients from food while turning waste into stool. The rectum is the last section of the large intestine, where stool is stored before leaving the body. Cancer can develop in either area, so the term “colorectal cancer” covers both colon cancer and rectal cancer.
Most colorectal cancers begin as small growths called polyps on the inner lining of the colon or rectum. While most polyps are not cancerous, some can change over time and become cancer. Finding and removing polyps early through screening can prevent colorectal cancer from developing.
Colorectal cancer is important because it can grow silently without symptoms in early stages. Regular screening is key to catching it early or preventing it by removing polyps. Early detection often means treatment can be more effective. Risk factors like age, family history, certain inherited genetic conditions, lifestyle habits such as smoking or heavy alcohol use, and chronic bowel diseases increase the chance of developing colorectal cancer.
Early colorectal cancer often causes no symptoms. When symptoms do appear, they may include changes in bowel habits lasting more than a few days, such as diarrhea, constipation, or feeling that the bowel does not empty completely. Blood in the stool, which can be bright red or very dark, abdominal pain or cramps, unexplained weight loss, and fatigue are other possible signs. However, these symptoms can also be caused by other conditions, so testing is needed to confirm a diagnosis.
Doctors may use several tests to diagnose colorectal cancer. A physical exam and a digital rectal exam can check for abnormalities. Screening tests like colonoscopy allow doctors to look inside the colon and rectum using a thin, flexible tube with a camera. Polyps or suspicious areas can be removed or biopsied during this procedure. Other tests may include stool tests, blood tests, and imaging scans.
Treatment depends on the cancer’s stage, location, and the patient’s overall health. Surgery is often used to remove cancerous tissue. Other treatments may include chemotherapy, radiation therapy, targeted therapy, or procedures like radiofrequency ablation or cryosurgery to destroy cancer cells. The care team will discuss the best options based on individual circumstances.
The term “colorectal cancer” can be confusing because it covers cancers in two different parts of the large intestine. It does not mean the same thing for every person, as the type, stage, and treatment can vary widely. Patients and caregivers can ask their care team about the exact location of the cancer, its stage, treatment options, and recommended screening tests. Understanding these details helps clarify what the diagnosis means for each individual.
This information is educational and cannot replace personalized medical advice. If you have concerns about colorectal cancer, screening, or symptoms, the best next step is to talk with your healthcare provider. They can guide you on screening tests, diagnosis, and treatment options tailored to your needs. Regular screening starting at age 45 is recommended for most people, and those with higher risk factors may need to start earlier.
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