Feasibility and clinical impact of next-generation sequencing (NGS) in patients with stage IV or recurrent malignancies.
e14697 Background: Feasibility and outcomes of routine NGS in patients with stage IV or recurrent malignancies remain debatable. Methods: We reviewed patients who underwent Foundation One NGS between 9/2012 and 10/2018 after diagnosis of stage IV or recurrent solid cancer at Cleveland Clinic. Overall survival (OS) was estimated by the Kaplan-Meier method. Logistic and Cox regression analysis were performed to identify predictors of receiving targeted gene therapy (TGT) and OS, respectively. Results: We identified 1699 patients, 825 (49%) were female, 1634 (96%) had stage IV and 65 (4%) had recurrent cancer. At diagnosis of stage IV/recurrent cancer, median age was 61 (range: 18 – 94) and ECOG performance score was 0, 1, and ≥ 2 for 578 (34%), 859 (51%), and 258 (15%) patients, respectively. Most common primary cancers were lung (20%), colorectal (17%), urothelial/prostate (12%), and breast (10%). NGS revealed median of 4 mutated genes (range: 0 – 34), ≥ 1 FDA approved TGT was available in 505 (30%) and 1114 (66%) patients for the same and different primary cancer, respectively. Overall, 219 (13%) patients received 247 lines of TGT for median of 3 months (range: 0.1 – 62) based on NGS results. TGT use was via clinical trials for 49 (22%) and off-label for 83 (38%) patients. Best response was complete/partial response for 63 (29%) and stable disease for 40 (18%) patients. Commonly targeted genes were EGFR (12%), ERBB2/3 (11%), BRAF (10%), BRCA1/2 (8%), and PIK3CA (7%). Median follow-up after diagnosis of stage IV/recurrent cancer was 19 months. Two-year OS for TGT and no TGT cohorts were 70% (95% CI: 64 – 77) and 55% (95% CI: 53 – 58), respectively (p < 0.0001). On multivariable analysis, ECOG ( < 2vs ≥2), systemic therapy between diagnosis of stage IV/recurrent cancer and NGS (≥2 vs < 2 lines), and each 1 increase in number of mutated genes were predictors of receiving TGT (p < 0.05 for all). On multivariable analysis, age (≤65 vs > 65), ECOG ( < 2vs ≥2), stage (recurrent vs IV), and systemic therapy before NGS (≥2 vs < 2 lines) predicted longer OS (p < 0.01 for all). Conclusions: In this large cohort, NGS provided further therapeutic options including clinical trials for approximately 1 out of 10 patients with stage IV or recurrent cancer.