Other findings from the trial include:
n Survival after recurrence was not strongly dependent on whether the site of first recurrence was liver, lung, or local. Long-term disease-free survival remained around 25% for patients grouped according to those recurrence sites. Survival appeared slightly better among patients who had lung or liver metastases, but that difference was not statistically significant. However, survival was lower in patients who had tumor resected from other sites (P < .04).
n Patients with single-site recurrence had better survival than patients with recurrences at multiple sites. Furthermore, 5-year survival was significantly higher for the patients having surgical resection of liver, lung, or local recurrences, compared with those who did not (P = .0001).
n Time to recurrence and initial stage were not prognostic factors in this study.
n The role of additional adjuvant therapy in patients who have a recurrence remains uncertain; 59 patients did receive further treatment, but there was no suggestion that more chemotherapy or radiotherapy affected survival after recurrence. Dr. O’Connell noted that "caution must be exercised with interpretation of these nonrandomized data."
In light of these data, follow-up care after potentially curative therapy for rectal cancer might include imaging studies every 6 months for the first 2 years, then annually for 5 years, Dr. O’Connell said. "The vast majority of these recurrences are within the first 2 years following resection, although there is a continuing lower incidence beyond that period of time," he said. He stressed that this is not an evidence-based recommendation but, rather, his own personal preference.
Elin R. Sigurdson, MD, PhD, surgical oncologist with Fox Chase Cancer Center, said that the findings confirm that there is a role for surgery in the management of metastatic disease. However, she said, it remains "very important" to seek molecular markers that show which patients are at risk for failure.
"Based on the numbers from this study, we are following 1,700 patients aggressively to salvage approximately 40 patients," Dr. Sigurdson said.