Saltz, Leonard

Abstract Systemic therapy has led to a median survival time for patients with advanced colorectal cancer (CRC) almost fourfold longer than that expected with best supportive care, an outcome achieved through combining chemotherapeutic and targeted biologic agents. Although the latter can include anti–epidermal growth factor receptor antibodies, such as cetuximab and panitumumab, we now have strong evidence that patients whose tumors harbor mutated KRAS will not benefit from this class of agent. Acceptance of the reliability and importance of the KRAS data took several years to evolve, however, for a variety of reasons. The timeline from the presentation and publication of small, retrospective phase II studies to widespread acceptance of the KRAS predictive value and changes in behavior—specifically, modifications of ongoing national trials in advanced/metastatic CRC, changes in national guidelines and practice patterns, and adjustments to the labeled indications for the monoclonal antibodies—was lengthy. In this commentary, we discuss whether or not the process of data disclosure regarding KRAS status and treatment of advanced CRC patients was effective in permitting timely decisions regarding ongoing publicly funded clinical trials and whether or not such decisions were rational and ethical. The overall goals are to highlight lessons learned regarding early disclosure of clinical trial results, as well as vetting and adoption of new scientific data, and to propose modifications for handling similar situations in the future.

PurposePerformance status (PS) is a prognostic factor in patients with metastatic colorectal cancer. Clinical trials typically enroll less than 10% of patients with a PS of 2 (PS2); thus, the benefit of systemic chemotherapy in PS2 patients is uncertain.Patients and MethodsIndividual data from 6,286 patients (509 PS2 patients) from nine clinical trials were used to compare treatment efficacy by PS. Progression-free survival (PFS), grade ≥ 3 adverse events, 60-day all-cause mortality, overall survival (OS), and response rate (RR) were explored in the full set of nine trials and in the five trials comparing first-line monotherapy with combination therapy.ResultsCompared with patients with PS of 0 or 1, PS2 patients had significantly higher rates of grade ≥ 3 nausea (8.5% v 16.4%, respectively; P < .0001) and vomiting (7.6% v 11.9%, respectively; P = .006) and 60-day all-cause mortality (2.8% v 12.0%, respectively; P < .0001). PS2 was prognostic for PFS (hazard ratio [HR] = 1.52; P < .0001; median PFS, 7.6 months for PS 0 or 1 v 4.9 months for PS2), OS (HR = 2.18; P < .0001; median OS, 17.3 months for PS 0 or 1 v 8.5 months for PS2), and RR (odds ratio = 0.61; P < .0001; 43.8% for PS 0 or 1 v 32.0% for PS2). The relative benefit and toxicity of experimental versus control treatment and monotherapy versus combination therapy were not different in PS 0 or 1 patients versus PS2 patients.ConclusionIn clinical trials, PS2 patients derive similar benefit from superior treatment as patients with PS of 0 to 1 but with an increased risk of toxicities and 12% 60-day mortality. Although current treatment provides benefit, new approaches are required to approach 1-year median survival for PS2 patients.

Purpose Obesity is a risk factor for the development of colon cancer. However, the influence of body mass index (BMI) on the outcome of patients with established colon cancer remains uncertain. Moreover, the impact of change in body habitus after diagnosis has not been studied. Patients and Methods We conducted a prospective, observational study of 1,053 patients who had stage III colon cancer and who were enrolled on a randomized trial of adjuvant chemotherapy. Patients reported on height and weight during and 6 months after adjuvant chemotherapy. Patients were observed for cancer recurrence or death. Results In this cohort of patients with stage III cancer, 35% of patients were overweight (BMI, 25 to 29.9 kg/m2), and 34% were obese (BMI ≥ 30 kg/m2). Increased BMI was not significantly associated with a higher risk of colon cancer recurrence or death (P trend = .54). Compared with normal-weight patients (BMI, 21 to 24.9 kg/m2), the multivariate hazard ratio for disease-free survival was 1.00 (95% CI, 0.72 to 1.40) for patients with class I obesity (BMI, 30 to 34.9 kg/m2) and 1.24 (95% CI, 0.84 to 1.83) for those with class II to III obesity (BMI ≥ 35 kg/m2) after analysis was adjusted for tumor-related prognostic factors, physical activity, tobacco history, performance status, age, and sex. Similarly, after analysis was controlled for BMI, weight change (either loss or gain) during the time period between ongoing adjuvant therapy and 6 months after completion of therapy did not significantly impact on cancer recurrence and/or mortality. Conclusion Neither BMI nor weight change was significantly associated with an increased risk of cancer recurrence and death in patients with colon cancer.

Purpose Regular physical activity reduces the risk of developing colon cancer, however, its influence on patients with established disease is unknown. Patients and Methods We conducted a prospective observational study of 832 patients with stage III colon cancer enrolled in a randomized adjuvant chemotherapy trial. Patients reported on various recreational physical activities approximately 6 months after completion of therapy and were observed for recurrence or death. To minimize bias by occult recurrence, we excluded patients who experienced recurrence or died within 90 days of their physical activity assessment. Results Compared with patients engaged in less than three metabolic equivalent task (MET) -hours per week of physical activity, the adjusted hazard ratio for disease-free survival was 0.51 (95% CI, 0.26 to 0.97) for 18 to 26.9 MET-hours per week and 0.55 (95% CI, 0.33 to 0.91) for 27 or more MET-hours per week. The adjusted P for trend was .01. Postdiagnosis activity was associated with similar improvements in recurrence-free survival (P for trend = .03) and overall survival (P for trend = .01). The benefit associated with physical activity was not significantly modified by sex, body mass index, number of positive lymph nodes, age, baseline performance status, or chemotherapy received. Moreover, the benefit remained unchanged even after excluding participants who developed cancer recurrence or died within 6 months of activity assessment. Conclusion Beyond surgical resection and postoperative adjuvant chemotherapy for stage III colon cancer, for patients who survive and are recurrence free approximately 6 months after adjuvant chemotherapy, physical activity appears to reduce the risk of cancer recurrence and mortality.