Wed, 22 Nov 2000

Diagnosing and treating colorectal cancer: Is there hope?

By Teoh Tiong Ann

This health column is jointly run by The Jakarta Post and Singapore-based Parkway Group Healthcare. Readers are encouraged to e-mail their questions to features@thejakartapost.com.

SINGAPORE (JP): Colorectal cancer is the most treatable form of cancer with an almost 100 percent cure rate in the earlier stages.

Colorectal cancer does not discriminate between the sexes, while in other cancers some are found more frequently in one gender than another. For both men and women, colorectal cancer is the most frequently diagnosed cancer, and, in the United States and many parts of the world -- according to the American Cancer Society -- it is the third leading cause of cancer deaths.

When colon cancer is found while it is still localized, the survival rate is 92 percent. When the cancer is detected later, the survival rate drops to 64 percent. Sadly, only 37 percent of cancer cases are diagnosed at an early stage.

For people with possible colorectal cancer, the most important factor in saving lives is to obtain a colorectal screening.

With colorectal cancer, everyone is potentially at risk. You are, however, considered to be in the "high risk" group if you have a personal history of polyps and/or tumors in the colon- rectum pathway. You are also at risk if you have a family history of relatives that have been diagnosed with polyps, chronic inflammatory bowel disease or colorectal cancer.

Little is known about the exact cause of this type of cancer. Studies are leaning towards a connection between diet, lifestyle and colorectal cancer.

For patients who are tested positive, the main treatment for colorectal cancer is surgery. Chemotherapy and radiotherapy may be necessary depending on the extent and stage of tumor. Many, if not most, colorectal cancers can be treated.

For many years, surgery has been directed mainly at achieving the best chance of a "cure" of the disease. Today, the primary intent of surgery has not changed, with "cure" still being the primary concern. However, there is additional attention to improve functional outcome after surgery. This serves to reduce the discomfort and change that one has to undergo after undergoing major colorectal surgery.

One of the greatest concerns of a patient undergoing surgery for colorectal cancer is the possibility of having a colostomy. With newer techniques and technology, the numbers of permanent colostomies that have to be created have been substantially reduced. Most mid and even some lower rectal cancers can be resected and reanastomosed without a permanent colostomy.

Morbidity rates have also decreased over the years. Thus, for most patients the outcome of surgery is favorable.

Depending on the stage of tumor, adjuvant chemotherapy and/or radiotherapy may be required. This has helped to improve survival, and decrease local recurrence rates. With newer chemotherapeutic agents, even patients with advances disease, derive some benefit from chemotherapy.

Thus treatment for colorectal cancer has become better, safer and improved results are obtained over the years.

Laparoscopy

Dr. T. Ravintharan, a consultant surgeon at the Mount Elizabeth Hospital, suggests patients with colorectal cancer undergo laparoscopy treatment.

Many surgical procedures are now being done by laparoscopy or Minimal Access Surgery (MAS). New and better equipment allows a magnified visual field, safe dissection and division of tissues and control of blood vessels. The technology has improved to the point that major open abdominal procedures like adrelectomy, splenectomy, fundoplication, gastrectomy and colorectal surgery can be carried out laparoscopically. This coupled with surgeons who are specially trained for laparoscopic surgery has enabled such major procedures to be done by MAS.

The advantages of MAS to the patient are in the faster recovery, shorter hospital stay and less pain.

The cost of surgery is the same or slightly higher than open surgery depending on the equipment used but is offset by the earlier hospital discharge and return to work. Cosmetically it is far better. Wound complications polyps, inflammatory bowel disease, sigmoid or caecal volvulus, rectal prolapse can all be treated with MAS. The surgery can be carried out with a small incision to remove the resected colon thus avoiding large abdominal incisions and its setbacks.

In the field of colorectal conditions, there is some concern about seeding the tumor when performing laparoscopic surgery. As the understanding of tumor cell biology and dissemination has improved, it has over the years been proven to be less of a problem. It has now been realized that handling of tumor under any situation including open procedures needs to be done in a careful manner and this decreases the incidence of implantation. Recent studies have shown that laparoscopic surgery for colorectal cancer can result in as complete excision as in open surgery and this includes the lymph nodes. As such the benefits of laparoscopic surgery are now been extended to patients with colorectal cancers in various stages.

Laparoscopic procedures like Right and Left-Helmi-colectomy, Sigmold or Anterior Resection and Abdominc-Perineal Resection have all been done. In certain instances, where the cancer is widespread and not suitable for resection, palliative bypass procedures or colostomy can be done without resorting to laparotomy. All this avoids the debilitating effects to patients of a large open incision, especially those with advanced cancers who have a limited lifespan, and allows them to recover quickly.

New advances and understanding of MAS in cancer surgery have now enabled trained laparoscopic surgeons to perform colorectal surgery with minimal morbidity and with as good a resection as that achieved in open procedures. This has brought the benefits of MAS to many patients with colorectal diseases, as is the case of patients who undergo gallstone surgery.

The writer is a consultant colorectal and general surgeon at Mount Elizabeth Medical Center in Singapore