NEW YORK (Reuters Health) – Patients with early (stage I and IIA) colon cancer derive similar benefits from intensive postoperative surveillance as those with late stage IIB and III colon cancer, clinicians report in the June 29 issue of the Journal of Clinical Oncology.

At present, it is unclear how best treat postsurgical patients with early-stage colon cancer, Dr. Heidi Nelson, from the Mayo Clinic, Rochester, Minnesota, and colleagues note in their report. “We have demonstrated that patients with early-stage disease who develop a recurrence benefit to at least the same extent as their late-stage counterparts from intensive follow-up.”

The findings are based on a secondary analysis of data from the Clinical Outcomes of Surgical Therapy (COST) trial for 537 patients with early-stage colon cancer and 254 with late-stage colon cancer.

The COST trial follow-up protocol included physical examination, including checking for recurrence at wound sites, plus carcinoembryonic antigen (CEA) testing every 3 months for the first year and then every 6 months for 5 years; chest x-ray every 6 months for 2 years and then annually; and colon evaluation, including colonoscopy or colon radiography, annually for the first year and then every 3 years if the colon was free of neoplasms; and computed tomography (CT) of the abdomen at the physician’s discretion.

The cumulative incidence of recurrence at 5 years was 9.5% in patients with early-stage disease and 35.7% in those with late-stage disease, and the median time to recurrence was 1.8 years and 1.4 years, respectively.

Salvage rates for early- and late-stage disease patients with recurrence were similar –35.9% and 37%, respectively, Dr. Nelson and colleagues report.

“Our analysis of the COST trial database confirms what was reported by the (2007) Cochrane review; that is, roughly one third of patients who experience recurrences after primary colon cancer resection can be treated with secondary curative-intent surgery when followed intensively after primary surgery,” the researchers write.

“Our report also confirmed that patients undergoing secondary surgery experience median survival of between 35.8 and 51.2 months,” which is similar to median survivals reported in the literature.

The data also indicate that patients with early-stage colon cancer were significantly less likely than patients with late-stage disease to experience multiple sites of first recurrence (3.6% vs 28.6%).

They also report that the methods of first detection of recurrence were similar between the two groups: CEA (29.1% vs 37.4%), CT scan (23.6% vs 26.4%), chest x-ray (7.3% vs 12.1%) and colonoscopy (12.7% vs 8.8%), for early- versus late-stage disease, respectively.

The COST trial data “support the frequent use of CEA and colonoscopy and suggests greater emphasis on lung imaging with less certainty on the value of abdomen and pelvis CT,” the investigators conclude.

“To our knowledge,” they add, “this is the first prospective study to test and confirm the hypothesis that patients with early-stage disease experience the same benefits as those with late-stage disease after curative intent secondary resection.”

Reference:
J Clin Oncol 2009.