THE NATIONAL-CANCER-INSTITUTE AUDIT OF THE AL-ADJUVANT-BREAST-AND-BOWEL-PROJECT-PROTOCOL-B-06

Background. The National Surgical Adjuvant Breast and Bowel Project (N SABP) Protocol B-06, a clinical trial sponsored by the National Cancer Institute (NCI), has provided evidence of the value of lumpectomy and breast irradiation for treating women with breast cancer in an early stage, Publicity generated by the discovery that the study included fr audulent data on patients enrolled by St. Luc Hospital in Montreal aro used concern about the overall accuracy of the data and conclusions. T o address this concern, the NCI conducted an audit of other participat ing institutions. Methods. In 1994, data on 1554 of the 1809 randomize d patients (85.9 percent) enrolled by centers other than St, Luc Hospi tal were audited at 37 clinical sites in North America, The audit incl uded data on eligibility, survival, disease-free survival, the length of time to a recurrence of cancer in the ipsilateral breast, and docum entation of signed informed consent. Results. End points were assessed for all 1554 patients, and eligibility was assessed for 1507 patients ; 47 patients were excluded because their forms were not complete or n ot returned. A total of 1429 patients had their eligibility status ver ified. Of a total of 7770 data points examined with respect to the num ber of positive nodes at base line, treatment characteristics, first e vents (excluding death), recurrence of cancer in the ipsilateral breas t, and survival, 7577 (97.5 percent) were verified, 123 (1.6 percent) could not be verified, and 70 (0.9 percent) were discrepant with the N SABP file. Of the 1554 patients, 1340 (86.2 percent) had all audited i tems (including eligibility) verified, 69 (4.4 percent) had at least o ne discrepant item, and 113 (7.3 percent) had at least one unverified item (as a result of missing or incomplete data); 32 (2.1 percent) wer e not assessed for eligibility but had no other discrepant or unverifi able items. Written informed consent was documented for 1098 patients before surgery and 210 after surgery; no date appeared on the signed f orm for 137. The informed-consent status was not verified for 71 patie nts and could not be determined for 38. The rates of verification of e nd-point data and documentation of written informed consent were simil ar among the total-mastectomy group, the lumpectomy group, and the gro up treated by lumpectomy and breast irradiation. Conclusions. The audi t confirms the adequacy of the data on which the reanalysis of Protoco l B-06 and the results after 12 years of follow-up are based.