Innovative Detection and Treatment Strategies for Colorectal Cancer

BUFFALO, NY—Recent advances in colorectal cancer detection and treatment planning are improving quality of life and disease control in colorectal cancer patients, according to research discussed at the Roswell Park Cancer Institute Surgical Oncology Symposium.

“Patients diagnosed with colorectal cancer can benefit from whole-body 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), both in staging and follow-up” said Ralph Doerr, MD, chief of surgical oncology, State University of New York at Buffalo, School of Medicine and Biomedical Sciences.

PET scans may allow the elimination of some tests used in the follow-up of patients with resected colorectal cancer. When the CEA rises in these patients, it is possible to use colonoscopy and then a PET scan for a focused work-up. CT scans can be used in a more limited fashion and may even be eliminated, Dr. Doerr said. “PET scanning can impact preoperative decision making and will affect the management of up to 63% of colorectal cancer patients,” he noted.

Up to 50% of all colorectal cancer patients will develop liver metastasis, he said. Generally only 10% to 15% of these patients will derive a survival benefit from surgical resection of the liver tumors. PET scanning can confirm which patients are able to benefit from resection.

In a University of Buffalo study, 20 patients with liver metastases were deemed resectable by CT and magnetic resonance imaging (MRI). When these same patients were examined using PET scans, 12 of the 20 were found to have either extrahepatic disease or extensive intrahepatic disease. No liver resection was performed in these 12 patients on the basis of PET scanning. The other eight patients were resected. “PET scanning offers surgeons the opportunity to offer the best treatment options available to their patients,” Dr. Doerr said.

Rectal Cancer

Although use of PET scanning is more limited in rectal cancer, new surgical techniques are impacting survival and quality of life for patients with rectal cancer.

“In the rectum, sphincter preservation techniques using staples and colon-anal reconstruction have made significant improvements in patients’ quality of life,” said Alfred M. Cohen, MD, chief of the Colorectal Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center. “Other advances for these patients include adjuvant chemoradiation, autonomic nerve preservation, and colonic J-pouch reconstruction.”

Many of these advances are due to a shift to use of a sharp mesorectal excision rather than a blunt pelvic dissection in rectal cancer patients, Dr. Cohen said. This newer technique improves the preservation of the mesorectum and the autonomic nerves that maintain sexual function in men. These changes also decrease the incidence of late bowel dysfunction, offering superior quality of life.

“In addition to these technical changes, improved staging and preoperative chemotherapy and radiation may increase overall survival and decrease morbidity,” Dr. Cohen said. “However, the need for clinical trials to confirm all of our observations is critical.