429P - Clinical utility and outcomes of liquid biopsy-based next generation sequencing in identification of actionable genomic mutations in solid malignancy: A single center retrospective study in the Philippines

Background

The clinical utility of next-generation sequencing (NGS) is not yet well documented in the Philippines. Liquid NGS is usually indicated for treatment selection and is done if a tissue biopsy is not possible and the specimen is insufficient. The study aims to determine the applicability of Liquid biopsy-based NGS in our setting and if this justifies the financial burden of ordering the test, the actual impact on selecting signal-matched therapies, and subsequent survival effects.

Methods

This is a retrospective cross-sectional study, and data will be collected among adult patients with advanced solid tumors who underwent FoundationOne®Liquid CDx at St. Luke’s Medical Center between January 2018 and December 2022.

Results

A total of 125 patients were included in the study. The most common tumor types were lung (n=40, 32%), colon (n=25, 20%), and breast (n=15, 12%). TP53 appears most frequently, occurring in 54% (n=68) of the analyzed samples. The mean number of previous systemic treatments was 1.96 (SD=1.4). The study identified 58 (46.6%) patients with actionable genomic mutations. Among the cohort, 28 (22.4%) were treated according to matched targetable genomic mutations, while the remaining 89 (71.2%) patients were treated with standard-of-care regimens. The median overall survival (OS) was 49 months (95%CI:41.63- 56.37) for the entire cohort. Patients in the Matched Therapy group (n=28) exhibited a notably extended median OS of 72 months (95%CI:37.64-106.36). In contrast, the Unmatched Therapy group (n=28) had a median OS of 29 months (95%CI:9.46-48.54). Patients in the Standard Therapy group (n=61) experienced a median OS of 46 months (95%CI:37.31-54.69). The Overall comparisons statistic demonstrated a significant difference among the groups (p=0.010).

Conclusions

OS was significantly longer in patients treated according to matched targetable genomic mutation than those who received standard-of-care treatments. Liquid biopsy may represent a less invasive and more feasible alternative to tissue biopsy in bringing personalized cancer treatment to routine clinical practice and potentially benefit patients in the future.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.