Colorectal cancer is the second most commonly diagnosed cancer in U.S. adults and the second leading cause of cancer-related deaths. Although about two thirds of patients undergo potentially curative resection, up to one half relapse and die of the disease. The optimal follow-up after initial resection has not been determined. Some experts think that intensive follow-up saves lives and lowers morbidity through early detection of recurrent disease or development of new primary malignancies. Renehan and colleagues examined all available evidence to determine any benefit from intensive follow-up protocols.
They searched electronic databases, reference lists, reviews of national meetings, registers of clinical trials, and other sources to identify relevant trials. Five completed trials that met inclusion criteria were identified, with six trials currently in progress. The five trials included 1,342 participants, and they all used survival at five years as a primary outcome measure. A variety of secondary outcomes were available, including various forms of recurrence and new malignancies. The trials assigned 666 patients to intensive follow-up and 676 to the control group. The form of intensive follow-up varied, but it usually incorporated computed tomography (CT) and carcinoembryonic antigen (CEA) monitoring.
In the intensive follow-up group, 197 patients (30 percent) died within five years compared with 247 (37 percent) in the control group. This significant difference was most pronounced in trials using CT and frequent CEA monitoring. The authors calculated an absolute reduction in mortality of 9 to 13 percent, with a number needed to treat of between eight and 11. The two groups did not differ in the rate of recurrence (32 percent), but recurrences were detected an average of 8.5 months earlier in the intensive follow-up group. Intensive follow-up was particularly effective in early detection of local recurrence.
The authors conclude that intensive follow-up significantly improves survival after resection for colorectal cancer. The benefit is equivalent to a 9 to 13 percent reduction in mortality and is largely attributable to early detection of isolated local recurrence. They call for further studies to determine the optimal components of intensive follow-up and to examine cost implications.
editor's note: After major surgery for colorectal cancer, we often schedule patients for office visits as an instinctive response to their needs. This study provides evidence that these visits, if properly conducted, have a positive effect on survival. The statistic of up to 13 percent reduction in mortality helps for that inevitable visit when the patient asks, “What's the point of all this follow-up?” More importantly, 70 percent of patients are alive at five years; a great statistic for the reactive phase around diagnosis when patients are convinced they are going to die within weeks.—a.d.w.