According to a recent article published in the Annals of Surgery, preoperative radiation may improve survival in patients with stage II rectal cancer that has not spread to any nearby organs or structures.
The rectum comprises approximately the last 10 inches of the colon, or large intestine. Stage II rectal cancer refers to cancer that has spread from the rectum to nearby tissues and/or nearby organs or structures and does not invade local lymph nodes. Stage III rectal cancer refers to cancer that may have spread to nearby tissues and/or nearby organs or structures and has spread to local lymph nodes. Patients with rectal cancer that has not spread to distant sites in the body may be cured through the complete surgical removal (resection) of their cancer. Recently, clinical studies have been evaluating and comparing radiation therapy in addition to surgery versus surgery alone.
The concept behind the use of pre-operative radiation is to shrink cancer and kill undetectable cancer cells that may exist directly outside the site of cancer origin. Current detection methods are not able to find or measure small amounts of cancer cells that exist, which increases the chance that they may be left behind following surgery. These cancer cells are responsible for cancer recurrences. In theory, through shrinking the site of cancer and killing nearby cancer cells, more complete surgical removal of the cancer may be obtained, resulting in fewer recurrences and improving chances for a cure.
Researchers from the Cleveland Clinic Foundation recently analyzed data from 259 patients with stages II-III rectal cancer within 8 centimeters from the anus who were treated with either preoperative radiation therapy plus surgery or surgery alone. This study involved patients whose cancer had spread to nearby tissues, but had not spread to nearby organs and/or structures. Ninety-two patients were treated with preoperative radiation therapy and 167 patients were treated with surgery alone. Five years following therapy, survival was improved from 58% to 72% in patients with stage II cancer (node-negative). There was no difference in survival between the two treatment groups in patients with stage III (node-positive) cancer. In addition, there was no survival advantage with either treatment in patients with cancers less than 2 cm or greater than 5 cm. In contrast to other previous clinical studies, there were no differences in the rate of local cancer recurrences.
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These researchers concluded that patients with stage II cancer that has not spread to nearby organs and/or structures, whose cancer is between 2 and 5 cm and are within 8 centimeters from the anus appear to have a definite survival advantage with preoperative radiation therapy, compared to surgery alone. Clinical trials that directly compare different treatment regimens in patients with differing disease characteristics are needed to confirm this finding. Patients with stage II rectal cancer may wish to speak with their physician about the risks and benefits of preoperative radiation therapy or participation in a clinical trial further evaluating this issue or other promising therapeutic approaches. Two sources of information regarding ongoing clinical trials include the National Cancer Institute ( cancer.gov) and www.eCancerTrials.com. eCancerTrials.com also provides personalized clinical trial searches on behalf of patients.
Reference: Delaney C, Lavery I, Brenner A, et al. Preoperative radiotherapy improves survival for patients undergoing total mesorectal excision for stage T3 low rectal cancers.
Annals of Surgery. 2002;236:203-207.
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