Rectal cancer is frequently mistaken for colon cancer because both conditions develop in neighboring sections of the large intestine and share several similarities in symptoms, diagnosis, and treatment approaches. However, despite their proximity within the digestive tract, rectal cancer presents unique challenges that distinguish it from colon cancer.
Rectal cancer originates in the final several inches of the large intestine, known as the rectum, which connects the colon to the anus. This area is located deep within the pelvis and surrounded by complex structures such as the bladder, reproductive organs, and nerves responsible for bowel control. Because of this close anatomical relationship, surgical treatment for rectal cancer tends to be more technically demanding than for colon cancer, requiring precise techniques to remove the tumor while preserving critical functions.
Another important difference is the higher risk of recurrence associated with rectal cancer. The confined space of the pelvic region makes it more difficult to achieve clear surgical margins, which can lead to cancer returning in the same area after treatment. For this reason, rectal cancer is often treated with a combination of therapies, including surgery, chemotherapy, and radiation therapy, to minimize the risk of recurrence and improve long-term outcomes.
Recognizing the early warning signs such as rectal bleeding, changes in bowel habits, unexplained weight loss, and persistent fatigue is vital for early diagnosis and effective treatment. Understanding how rectal cancer differs from colon cancer helps patients and caregivers make more informed decisions about screening, management, and follow-up care.
What is Rectal Cancer?
Rectal cancer is the development of cancerous cells in the rectum, which, along with the colon, forms part of the digestive system. Because of this close relationship, rectal and colon cancers are often collectively called colorectal cancer. As with most cancers, early detection and treatment are critical for better outcomes.
Causes and Risk Factors
The exact cause of rectal cancer remains unknown, but it generally involves the uncontrolled growth of abnormal cells that can invade and damage healthy tissue. Several factors may increase the risk of developing rectal cancer, including inherited genetic mutations such as hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome) and familial adenomatous polyposis (FAP). HNPCC significantly increases the risk of colon and other cancers, sometimes leading to preventive removal of the colon. FAP is a rare condition that causes numerous polyps in the colon and rectum, which can become cancerous. Additional risk factors include prior radiation therapy to the abdomen, as well as other medical conditions and lifestyle choices.
Symptoms of Rectal Cancer
Rectal cancer may not cause symptoms in its early stages, but as it advances, common signs can include rectal bleeding, changes in bowel habits, a persistent feeling of incomplete bowel emptying, pain during bowel movements, diarrhea or constipation, blood or mucus in the stool, unintentional weight loss, unexplained fatigue, and abdominal discomfort, gas, cramps, or pain. Additionally, iron-deficiency anemia often caused by chronic blood loss”can also indicate rectal cancer.
Diagnosis of Rectal Cancer
Diagnosing rectal cancer usually involves multiple approaches, including physical examinations, screening procedures, colonoscopy, blood tests, and imaging studies. A physical exam may include a rectal examination to detect lumps or abnormalities. Screening tests, such as a fecal immunochemical test (FIT) or sigmoidoscopy, can help identify signs of cancer early. Blood tests may be used to check for anemia or tumor markers. Imaging techniques like endorectal ultrasound, CT scans, PET scans, and MRI are essential to determine the extent and stage of the cancer.
Stages of Rectal Cancer
Rectal cancer is staged based on how far it has spread and the progression of the disease. Staging helps determine the most appropriate treatment options depending on how far the disease has spread. The stages of rectal cancer include:
- Stage 0 (carcinoma in situ): Abnormal cells are found only in the innermost layer of the rectum wall.
- Stage 1: Cancer cells have spread beyond the innermost layer but have not reached the lymph nodes.
- Stage 2: Cancer cells have spread into or through the outer muscle layer of the rectum wall but not to
lymph nodes. In stage 2B, the cancer may have spread into the abdominal lining. - Stage 3: Cancer cells have spread through the outermost muscle layer of the rectum and to one or more lymph nodes. Stage 3 is further subdivided into substages based on the extent of lymph node involvement.
- Stage 4: Cancer cells have spread to distant sites, such as the liver or lungs.
Treatment Methods
Treatment for rectal cancer is tailored to several factors, including tumor size, cancer stage, patient age, and overall health. Common treatment options include surgery, radiation therapy, chemotherapy, targeted therapies, cryosurgery, radiofrequency ablation, stent placement, and palliative care to enhance quality of life. The choice of therapy varies by stage”for instance, stage 0 may only require removal of suspicious tissue during a colonoscopy, while stages 2 and 3 typically need a combination of surgery, radiation, and chemotherapy. Stage 4 treatment may involve multiple surgeries, radiation, chemotherapy, and targeted therapies. Participation in clinical trials is also an option, offering access to new and emerging treatments while contributing to scientific research.
* Liv Hospital Editorial Board has contributed to the publication of this content .
* Contents of this page is for informational purposes only. Please consult your doctor for diagnosis and treatment. The content of this page does not include information on medicinal health care at Liv Hospital .
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Frequently Asked Questions
What are the early symptoms of rectal cancer?
Early signs include rectal bleeding, blood in the stool, changes in bowel habits, abdominal discomfort, fatigue, and unexplained weight loss.
How is rectal cancer diagnosed?
Diagnosis involves a rectal exam, colonoscopy, biopsy, and imaging tests like MRI, CT, or PET scans to determine the stage and extent of the disease.
Is rectal cancer different from colon cancer?
Yes. Though both are part of colorectal cancer, rectal cancer occurs in the last part of the intestine and often requires more complex surgery due to its position in the pelvis.
What are the stages of rectal cancer?
Rectal cancer has five stages, from stage 0 (limited to the inner lining) to stage 4 (spread to distant organs such as the liver or lungs).
How is rectal cancer treated?
Treatment may include surgery, chemotherapy, radiation therapy, or targeted therapy. The choice depends on the stage, tumor size, and patient health.
What is the survival rate for rectal cancer?
When diagnosed early, rectal cancer is highly treatable, and survival rates are significantly higher compared to advanced stages.
Can rectal cancer return after treatment?
Yes. Rectal cancer has a higher chance of recurrence due to its location, which is why follow-up imaging and monitoring are crucial.
How can rectal cancer be prevented?
A healthy diet rich in fiber, regular screenings, maintaining a healthy weight, exercising, and avoiding smoking or excessive alcohol help lower risk.
Why choose Liv Hospital for rectal cancer treatment?
Liv Hospital in Turkey offers advanced diagnostic imaging, expert oncologists, and personalized treatment plans with a multidisciplinary approach for optimal care.