Treating Colorectal Cancer
Virginia Mason's Interdisciplinary Approach
Virginia Mason's team of specialists in Seattle includes physicians in general gastrointestinal surgery, gastroenterology, radiology, pathology, medical oncology and radiation therapy. Patients also receive support from a team of skilled nurses, social workers, psychologists, dietitians and enterostomal therapists, all of whom have advanced education in caring for patients with cancer.
These specialists work together to ensure coordinated care, good communication and an aggressive but individualized approach to treatment.
Advances in Chemotherapy for Colorectal Cancer
Over the last decade, there have been major advances in the effectiveness of chemotherapy for patients with colorectal cancer. Multiple studies have demonstrated improved survival and improved quality of life in patients using newer chemotherapy agents and protocol. Studies are ongoing to further improve treatment for these patients.
Surgery for Colorectal Cancer
The majority of patients with colon cancer undergo surgery with removal of the tumor and anastomosis or reconnection of the colon as the first step of their treatment. Few patients are treated before surgery with chemotherapy or radiation therapy. If the tumor has ruptured or blocked the intestines at the time of presentation, emergency surgery and a temporary colostomy may be necessary. Also, the Gastrointestinal Cancer Team at Virginia Mason now has technology which permits "stenting" of obstructing tumors, thus making emergency surgery for obstructing colon cancers very infrequent.
The sequencing of treatments in patients with rectal cancers is complex and largely determined by the preoperative staging of the tumor. Large tumors or tumors with cancer in the lymph nodes should receive radiation and chemotherapy before surgery, so-called "neoadjuvant" treatment. Primary surgery is either a low anterior resection or an abdominal-perineal resection. Abdominal-perineal resection, or APR, is used for cancers located close to the anus and involves removal of the rectum from both an abdominal incision as well as an incision around the anus. Since the anus and the anal sphincters are removed, a permanent colostomy is required.
Tumors of the mid- or upper rectum can be removed through an abdominal incision and the colon attached to the lower rectum or anus as a "low anterior resection" or a colo-anal anastomosis (see below). On rare occasions, very early cancers near the anus can be removed through the anus without a skin incision.
The fear of every patient with rectal cancer is the possibility of a permanent stoma or colostomy. The traditional operation for most patients with mid- and low-rectal cancers was abdominal-perineal resection, or APR. This operation provides good local control of the cancer but results in a colostomy. Operations that remove rectal cancers without affecting the anal sphincter, thus preserving fecal continence and maintaining normal bowel function, are called "Sphincter-Preservation" procedures. Advances in surgical techniques utilized at Virginia Mason have enhanced our surgeons' ability to achieve sphincter-preservation in most of our rectal cancer patients. The traditional colo-rectal anastomosis can be achieved 4-6 cm's from the anus. However, rectal cancer patients at Virginia Mason can now be treated with a colo-anal anastomosis at the anal canal, thus removing the entire rectum and increasing the chances of sphincter-preservation.
Another key element of sphincter preservation techniques utilized at Virginia Mason is the use of Colonic J-Pouches (see figure). A crucial factor in fecal continence is compliance of the rectum. For example, patients with radiation to the rectum lose compliance and frequently complain of fecal soilage. The sigmoid colon is non-compliant. Thus, sigmoid colon to low-rectum or anal anastomoses may result in poor bowel function. The use of colon pouches, as illustrated, will enhance compliance of the new rectum, resulting in improved continence and decreased stool frequency.
Our surgeons are on the cutting edge of the development of technical advances that are producing enhanced local control rates and quality of life. Appreciation of the importance of total mesorectal excision and nerve-sparing techniques are resulting in higher cure rates and decreased chances of sexual impotency, respectively.
In summary, few patients with rectal cancer treated at Virginia Mason will require permanent colostomies. New surgical techniques facilitate sphincter preservation, enhance local cancer control rates and improve bowel and sexual function.
Total Mesorectal Excision (TME)
The lymph nodes of the rectum may contain metastatic deposits of cancer cells. Total mesorectal excision (TME) is a surgical technique that improves the surgeon's ability to remove all of the rectal lymph nodes at risk for containing cancer cells. Several studies have shown that the risk of rectal cancer recurring after surgery is lower if the surgeon performs a TME. Surgeons at Virginia Mason are experts performing the total mesorectal excision or TME in patients with rectal cancer.
Sexual Potency and Nerve Preservation
Damage to the nerves controlling erection or sexual potency is common after surgery for rectal cancer. Together with the development of Total Mesorectal Excision (see TME above), surgeons have developed techniques to preserve the nerves that control sexual potency. The surgical team at Virginia Mason is trained in these nerve preservation techniques. Therefore, the majority of our patients with rectal cancer who undergo surgery for rectal cancer maintain sexual potency.