Patients with metastatic CRC may not need removal of asymptomatic colon tumor

Despite better screening for colorectal cancer (CRC), about 1 in 5 newly diagnosed patients will have metastatic CRC that already has spread to distant organs.  Many will have symptoms of fatigue or weight loss, but only a minority will have symptoms (significant bleeding or abdominal pain, or a blocked bowel) caused by the colon tumor itself.

In those people first diagnosed with stage IV CRC, about 80% have metastases that cannot be removed by surgery. There’s been intense debate—but no clear evidence—about whether patients whose colon tumor isn’t causing symptoms should have the colon tumor surgically removed routinely before they start chemotherapy. 

A recent important study provides the first evidence that such patients often do just as well to start systemic chemotherapy immediately without having their colon tumor surgically removed.

The National Surgical Adjuvant Breast and Bowel Project (NSABP) trial is the first—and only—prospective multi-institutional study to study patients to see if they could be safely treated without initial surgery to remove a colon tumor not causing them symptoms. Results and an accompanying editorial were published in the August 6^th Journal of Clinical Oncology. 

Colon surgery in people who have metastatic CRC can cause many more complications than surgery in people with early CRC. Previous retrospective studies (looking back in time) have shown a 30-day post-surgical death rate as high as 10% in metastatic cancer patients. Other studies have indicated that only 10 to 20% of those patients without primary-tumor symptoms will develop problems from the colon tumor itself. 

In this prospective, Phase II study, 86 patients (average age 58 years) were started immediately on a FOLFOX plus bevacizumab (Avastin) chemotherapy regimen. After a median follow-up of 20.7 months, results showed that most of the patients could be successfully managed without surgery. Complications from the primary colon tumor did arise in 12—or 14%–of the patients: Ten needed surgery (8 for obstruction, 1 for perforation, 1 for pain), and there were 2 deaths.

In this particular study, then, 86% of the patients did not develop problems from the primary colon tumor that needed surgical removal or that shortened their survival time.

In an accompanying editorial, Dr. George Chang of MD Anderson Cancer Center noted that this initial, small study doesn’t settle the debate about how to start treatment in these patients. One major difficulty is deciding which patients are truly “asymptomatic” from their primary colon tumor. Another problem is that the study’s participants were relatively young; and elderly patients suffer significantly more complications for later, emergency surgery to remove a primary tumor.

The jury is still out.

WHAT THIS MEANS FOR PATIENTS

Most doctors, and most patients with newly diagnosed stage IV colorectal cancer whose metastases cannot be surgically removed, at least initially, likely will decide to surgically remove the primary colon tumor before starting chemotherapy.

However, if the patient really has no symptoms of obstruction, perforation, bleeding or pain from the colon tumor itself, some oncologists may discuss the option of not doing colon surgery initially so that chemotherapy can begin sooner.  

As always, the decision will depend on the patient’s specific cancer and metastases, age and health status, and other highly personal factors.

Sources: August 6, 2012 Journal of Clinical Oncology original article and accompanying editorial ; and August 9, 2012 Medscape