A study has found that most patients with metastatic colorectal cancer don't require immediate surgery to remove the primary tumour in the colon.
"For this population with metastatic disease that cannot be cured by surgery, undergoing colon surgery is not always necessary," said Philip Paty, a surgical oncologist at Memorial Sloan-Kettering Cancer Center (MSKCC) and one of the study's lead authors.
"If the colon tumour is not causing obstruction, perforation, or bleeding we've found these patients are best treated with chemotherapy. By moving straight to chemotherapy, patients can avoid the risk of surgical complications and can start treatment for all sites of disease without delay," he added.
For the study, researchers looked at 233 metastatic colorectal cancer cases treated at MSKCC from 2000 to 2006.
Their analysis showed that 217 of the 233 patients, or 93 percent, did not have complications that required resection of the primary tumour. Only 16 patients required colon surgery for symptom management.
Previously, in the conventional approach to treating stage IV disease, patients underwent colon surgery immediately following their diagnosis and would typically start chemotherapy treatments three to six weeks later.
The rationale for immediate colon resection was to prevent future symptoms and complications from the primary tumour. It was assumed that the majority of colorectal cancers would have little response to chemotherapy.
However, with the development of better chemotherapy treatments in the past decade, scientists started looking at patients with stage IV disease differently, and began to administer chemotherapy as initial treatment.
Such treatments seemed to be reliable in shrinking both colon tumours and the metastases but there was not published data to support this approach.
"We now know that the routine use of surgery for these patients is based on old thinking, and we're beyond that. There will always be the need for individual exceptions based on the clinical situation, but our default position should be not to operate," said Paty.
The study was presented at the American Society of Clinical Oncology Annual Meeting.