Participants in prospective, randomized clinical trials for resected non-small cell lung cancer have improved survival compared with nonparticipants in such trials

Abstract

The survival of 78 patients with resected non-small cell lung cancer entered in prospective, randomized investigational trials is compared to that of a population-based group of control patients not included in such trials. The survival of trial patients is significantly better than that of controls (P less than 0.001). This survival advantage for trial participants is most apparent among late Stage I patients, and is observed after matching for known prognostic factors (i.e., primary tumor size, nodal status, tumor histology) and after adjusting in the analysis for age, sex, and the administration of radiation therapy. Several explanations for the improved outcome for trial patients are explored, including differences in preoperative evaluation, staging, surgical technique, placebo effects, and patient motivation. These results suggest the possibility that inclusion in these controlled cancer trials may have had an inherent advantage for all participants.

Selection of Patients may Limit the Generalizability of Results from Cancer Trials

“…However, for most trials, no records concerning non-included eligible and ineligible patients are kept (3), and assessments of the generalizability of trial results are thus not possible or at least limited. Better survival for trial patients as compared to eligible non-participants has, however, been demonstrated in a nephroblastoma trial (12), a sarcoma trial (1), and a pooled analysis of several non-small cell lung cancer trials (11). These observations are supported by our analysis.…”

“…Secondarily, it may be of interest to know what proportion of all available patients with the malignancy studied was in fact eligible for the trial. It is often stated that patients enrolled in a trial have a more favourable outcome than those not included, irrespective of the speci c treatment that is evaluated (1,11,12). Even though trial patients and non-trial patients receive the same standard treatment, differences in outcome are observed.…”

Management of ovarian cancer: referral to a multidisciplinary team matters

“…All Evidence has existed for some time that participation in clinical trials (Lennox et al, 1975;Davis et al, 1985;Karjalainen & Palva, 1989;Stiller & Draper, 1989) and referral to specialist centres (Stiller, 1988;Karjaainen, 1990, Harding et al, 1993 confer survival advantage on patients with certain types of cancer. These benefits have been seen in the treatment of childhood cancers (Lennox et al, 1975;Stiller, 1988;Stiller & Draper, 1989), teratoma (Harding et al, 1993), multiple myeloma (Karjalainen & Palva, 1989), nonsmall-cell lung cancer (Davis et al, 1985) and breast cancer (Karjalaien, 1990). Our study has identified specific aspects of the clinical management of ovarian cancer which are associated with improved survival.…”

Characteristics and outcomes of patients with advanced non-small-cell lung cancer who declined to participate in randomised clinical chemotherapy trials

“…In majority of the reports comparing outcomes between participants and non-participants of clinical trials, however, the non-participant 'controls' were chosen from differently pooled database, which could include baseline imbalances between groups and hindsight bias (Davis et al, 1985;Braunholtz et al, 2001;Peppercorn et al, 2004). In this study, we compared the characteristics and outcomes of those who met the eligibility criteria but declined to participate in randomised trials, and instead chose to receive standard therapy.…”