ORLANDO—Routine surgery to remove the primary tumor in patients with unresectable colon metastases is no longer necessary, according to a group at New York’s Memorial Sloan-Kettering Cancer Center. They based their decision on six years of clinical experience at their institution and reported on them at ASCO 2009.
While surgery to remove the primary tumor is known to be of uncertain benefit, the practice is common. “The rationale is that surgery prevents future complications, such as obstruction, bleeding, and perforation,” said Philip Paty, MD, attending surgeon and vice chair of clinical research at the cancer center. “There are few data that quantitate the results of not surgically intervening.”
The study was a retrospective analysis of 233 consecutive patients presenting with metastatic colorectal cancer between 2000 and 2006 who underwent standard chemotherapy (some received bevacizumab [Avastin] as well) but not surgery. Patients were free of local symptoms from their tumor (abstract CRA4030).
Of the 233 patients, 207 (89%) never developed colon problems that required urgent surgery. Ten (4%) developed colon obstruction that was successfully treated with stents or radiation rather than surgery. Sixteen (7%) did require nonelective colon surgery for obstruction (n = 13) or perforation (n = 3), and two of the 16 patients (0.8%) died due to surgical intervention, Dr. Paty said.
“This compares favorably to historical data showing a mortality rate of 1% to 5% with upfront surgery that is done routinely,” he pointed out. Overall, 93% of patients never required colon surgery to treat complications from their primary tumor. These patients were able to begin chemotherapy immediately, thus avoiding the costs and risks of surgery.
“We believe a nonsurgical approach should become standard practice,” Dr. Paty said.
His group recently published a paper in the Journal of Clinical Oncology on the outcome of primary tumor patients with synchronous stage IV colorectal cancer who received oxaliplatin-based or irinotecan-based, triple-drug chemotherapy without initial surgery.
They found that the majority of the patients (93% of 233) did not require palliative surgery for their intact primary tumor.
“These data support the use of chemotherapy, without routine prophylactic resection, as the appropriate standard practice for patients with neither obstructed nor hemorrhaging primary colorectal tumors in the setting of metastatic disease,” Dr. Paty’s group wrote (J Clin Oncol 27:3379-3384, 2009).
Nicholas Petrelli, MD, who chaired the ASCO press conference on gastrointestinal cancers, commented that because asymptomatic patients often get unnecessary surgery, the results out of Memorial Sloan-Kettering have implications for these patients and their physicians. Dr. Petrelli is medical director at Helen E. Graham Cancer Center in Newark, Del., and a professor of surgery at Thomas Jefferson University in Philadelphia. An ongoing multicenter trial conducted by the NSABP (C-10) is evaluating whether surgery is needed for the asymptomatic primary tumor in patients with synchronous, unresectable, distant metastases, who will also receive modified FOLFOX6 plus bevacizumab.
Operative approach, low mortality
In an intereview with Oncology News International, Nancy Baxter, MD, noted that “only 11% of patients had complications from the primary tumor requiring intervention, and overall those necessitating an operative approach had very low mortality that compared well to other studies. However, 30% did undergo some form of surgery during follow-up.”
While this large study used current chemotherapy, its limitations included the lack of a comparison group and the selection of the whole group for upfront chemotherapy, said Dr. Baxter, who is an associate professor of surgery at the University of Toronto and St. Michael’s Hospital.
“From this study, we can conclude that in stage IV colon cancer patients selected for upfront chemotherapy, there is an acceptable rate of complications related to the primary, though surgery often becomes part of the treatment plan,” she said.