Development and independent validation of a prognostic assay for stage II colon cancer using formalin-fixed paraffin-embedded tissue, Kennedy et al., Journal of Clinical Oncology (2011)

Kennedy et al. reported the development process of the GeneFx® Colon test and the results of a prospectively designed and executed, blinded, non-interventional study of 144 retrospectively accrued, archived, FFPE samples.

Results: patients classified as high risk by the GeneFx Colon test experienced significantly shorter Recurrence-Free Survival (RFS) than patients classified as low risk [HR: 2.53, 95% CI 1.54-4.45, p-value<0.001]. The signature also predicted cancer-related death with an HR of 2.21 in the high risk group.

The signature was shown to perform independently from known prognostic factors. Prognosis was significantly predicted in both the univariate (p<0.001) and multivariate (p<0.001) analysis, which demonstrates that this signature provided prognostic information in addition to conventional risk factors.

Association between results of a gene expression signature assay and recurrence-free interval in patients with stage II colon cancer in cancer and leukemia group B 9581 (Alliance), Neidzweicki et al., Journal of Clinical Oncology 2016

Niedzweicki et al. of the CALGB Alliance 9581 studied the association between GeneFx Colon and recurrence-free interval in stage II colon cancer. The prospectively designed study used archived FFPE samples from 393 patients enrolled in a phase III prospective, randomized drug trial.

Results: Patients classified as high risk experienced a significantly shorter recurrence-free interval than low risk patients. Multivariate analysis showed GeneFx Colon is prognostic of RFS and is independent from known prognostic factors.

Competitor analysis using CALGB 9581 patient cohort

Although not a direct head-to-head comparison, patients from the same CALGB Alliance 9581 patient cohort were utilized to validate the Oncotype DX Colon risk of recurrence test.


1. Kennedy R, et al: Development and Independent Validation of a Prognostic Assay for Stage II Colon Cancer Using Formalin-Fixed Paraffin-Embedded Tissue. J Clin Oncol 29:4620-6, 2011

2. Niedzwiecki D, Venook AP, et al: Association between results of a gene expression signature assay and recurrence-free interval in patients with stage II colon cancer in cancer and leukemia group B 9581 (Alliance). J Clin Oncol. 2016;34:3047-53

3. Venook AP, Niedzweicki D, et al: Biological determinants of tumor recurrence in stage II colon cancer: validation study of the 12-gene recurrence score in cancer and leukemia group B (CALGB) 9581. J Clin Oncol 31(14):1775-1781