Rectal Cancer

What is Rectal Cancer?

Rectal Cancer is a malignant tumor arising from the lowest 15 centimeters of the intestines, lying within the pelvis, and connecting the colon to the anus. Rectal cancer, unlike colon cancer, has a tendency to recur locally within the pelvis in the other organs near the colon and has a worse outcome. Local recurrence of rectal cancer is common (15-45%) after standard surgery and is often catastrophic. It is difficult to cure, and the associated symptoms are debilitating. Accordingly, preventing local recurrence is one of the main treatment goals with rectal cancer. Roughly one third of all colorectal cases involve the rectum.

 

How does one know if one has rectal cancer?

Rectal cancer can cause many symptoms that require a person to seek medical care. However, rectal cancer may also be present without any symptoms, hence it is important to have routine health screening check up. Symptoms to be aware of include the following:

• Bleeding

-          Seeing blood mixed with stool is an urgent sign. Although many people bleed due to hemorrhoids, a doctor should still be notified in the event of any rectal bleeding. It is a sad fact that many patients with rectal cancer attribute their symptoms to hemorrhoids, causing them to delay consultation.

-          Prolonged rectal bleeding (perhaps in small quantities that is not seen in the stool) may lead to anemia, causing fatigue, shortness of breath, light-headedness, or a fast heartbeat.

• Obstruction

-          A rectal mass may grow so large that it prevents the normal passage of stool. This blockage may lead to the feeling of severe constipation or pain when having a bowel movement. In addition, abdominal pain or cramping may occur due to the blockage.

-          The stool size may appear narrow so that it can be passed around the rectal mass. Therefore, pencil-thin stool may be another sign of an obstruction from rectal cancer.

-          A person with rectal cancer may have a sensation that the stool cannot be completely evacuated after a bowel movement, requiring frequent trips back to the bathroom.

• Weight loss, usually unexplained.

 

 

Who are at risk/what are the risk factors?

The actual cause of rectal cancer is unclear. However, the following are risk factors for developing rectal cancer:

• Increasing age
• Smoking
• High-fat diet and/or diet mostly from animal sources
• Personal or family history of polyps or colorectal cancer
• Lack of screening for colorectal cancer

 

What happens when you have rectal cancer?

Rectal cancer usually develops over several years, first growing as a benign precancerous growth called a polyp. Some of these polyps will eventually turn into cancer and begin to grow and penetrate the wall of the rectum, after which they spread into the lymph nodes and reach other organs like the liver and lungs.

 

How is rectal cancer diagnosed? When / who do you consult?

Screening for colorectal cancer is the only way to prevent this disease. Screening tests for rectal cancer include the following:

• Fecal occult blood test (FOBT)
• Endoscopy, wherein a doctor inserts a scope through the anus. The scope may be rigid, as in proctosigmoidoscopy, or flexible and connected to a video camera, as in colonoscopy (which views the lower half of the colon).

If a rectal tumor is found on endoscopy, a biopsy is performed. If the biopsy confirms that it is rectal cancer, the next important phase in management is accurate staging of the disease, which will determine the appropriate treatment. Stage 1 patients can be treated by surgery alone, while Stage 2 and 3 patients will require radiochemotherapy prior to surgery. The treatment for Stage 4 patients is best individualized. The tests to stage rectal include:

• Endorectal ultrasound is a special test available at TMC where a special ultrasound probe is inserted into the anus, has grown into the rectal wall; whether there is spread to the lymph nodes around the area; and whether there is invasion into the anal muscles.
• CT scan and MRI to evaluate the tumor in relation to the pelvis, as well as check for spread to the liver.
• Chest x-ray or CT scan of the lungs
• CEA blood test 

 

What are the available treatment options?

The standard surgical procedure is called wide or total mesorectal excision. Preoperative chemoradiotherapy has been found to reduce the risk of local recurrence and to cause fewer long-term toxic effects than if the chemoradiotherapy is given postoperatively. At five years, the overall survival among patients with locally advanced rectal cancer, irrespective of whether they have had preoperative or postoperative chemoradiotherapy, is about 75%.

A common concern among patients with rectal cancer is possibility of a permanent colostomy, where the anus is removed and feces is made to come out of an opening in the abdominal wall. Thankfully, with the appropriate use of preoperative chemoradiotherapy and the surgical technique of total mesorectal excision, surgeons are now more able to preserve the anus during rectal cancer surgery. However, these highly complex operations usually will necessitate the creation of a temporary colostomy in order to prevent the passage of feces into the freshly reconstructed anus. This temporary colostomy is then closed in a separate operation later, when the anus is completely healed.

At present, a permanent removal of the anus, with the creation of a colostomy, is only performed if there is evidence on endorectal ultrasound that the anal muscles are involved. This situation is uncommon, and occurs in less than 20% of the cases.

 

What are the outcomes of rectal cancer?

The outlook for recovery from rectal cancer is unique for each individual. Many factors are involved when considering the chance of survival after rectal cancer treatment. Long-term survival generally depends upon the stage of the cancer at the time of diagnosis and treatment.  

Treatment of colon cancer depends on the stage, or extent, of disease.

According to stage, the following approximations of the likelihood of survival 5 years after treatment are as follows:

• Stage I: The cancer is in the inner layers of the rectum, and the probability of being alive in 5 years is approximately 70-80%.
• Stage II: The cancer has spread through the muscle wall of the rectum, sometimes invading adjacent organs like the urinary bladder, vagina or prostate. The probability of being alive in 5 years is approximately 50-60%.
• Stage III: The cancer has spread to the lymph nodes, and the probability of being alive in 5 years is approximately 30-40%.
• Stage IV: The cancer has spread to other organs far from the rectum, like the liver and lungs. The probability of being alive in 5 years is less than 10%.

 

In The Medical City, what are the related services available?

• Screening

1. Fecal occult blood yearly with flexible sigmoidoscopy every 3 years
2. Colonoscopy every 5 to 10 years
3. Virtual CT Colonography every 3 to 5 years

• Prevention

1. Colonoscopic Polypectomy

• Comprehensive Rectal Cancer Treatment Program

-          State-of-the-art Staging Modalities

1. Endorectal Ultrasound
2. Triphasic CT scan
3. MRI

-          Multidisciplinary Treatment Planning

-          Neo-adjuvant (Pre-operative) Chemoradiotherapy

-          State-of-the-art Surgery

1. Total Mesorectal Excision
2. Sphincter-preservation, avoiding permanent colostomies
3. Pelvic Nerve preservation
4. Minimally invasive surgery

Note: This information is not intended to be used as a substitute for professional medical advise, diagnosis or treatment.   If you or someone you know have any of the symptoms mentioned above, it is advisable to seek professional help.

Sources:

1. Http://www.medicinenet.com
2. http://emedicinehealth.com
3. Philippine Cancer Facts and Estimates
4. The Medical City Cancer Center

For more information, please call:

 

CANCER CENTER

Tel. no. (632) 988-1000 / (632) 988-7000 ext. 6214

 

CENTER FOR PATIENT PARTNERSHIP

Tel. no. (632) 988-1000 / (632) 988-7000 ext. 6444