The detection value of PD-L1 expression in biopsy specimens and surgical resection specimens in non-small cell lung cancer: a meta-analysis.

BACKGROUND

The detection value of different types of specimens for programmed death ligand-1 (PD-L1) expression remains controversial. As such, the purpose of this meta-analysis was to compare the detection value of biopsy specimens and surgical resection specimens for PD-L1 expression in patients with non-small cell lung cancer (NSCLC).

METHODS

PubMed and Web of Science were searched prior to December 2020 to identify studies that compared the detection value of biopsy specimens and surgical resection specimens for PD-L1 expression in NSCLC. Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 scale was used to evaluate the quality of the literature included. The detection value of different types of specimens for PD-L1 expression was then assessed. Besides, the relative risk (RR) with 95% CI were pooled using Review Manager 5.3 software and Stata 14.0 software.

RESULTS

The meta-analysis involved 12 articles and included 877 patients. There was no significant difference in the detection rate of PD-L1 at the 1% cutoff between biopsy specimens and surgical resection specimens (RR =0.89, 95% CI: 0.70-1.12, P=0.33). However, there was a significant difference between two groups when the cutoff is 50% (RR =0.69, 95% CI: 0.58-0.83, P<0.01). In addition, a subgroup analysis of the type of biopsy specimens and the PD-L1 qualitative immunohistochemistry (IHC) assays showed that the detection rate of PD-L1 in small biopsies and using the SP142 antibody were lower than in surgical specimens and using other antibodies for both the 1% and 50% cut-offs (P<0.01).

CONCLUSIONS

Current evidence suggests that caution must be taken when using biopsy specimens from patients with advanced NSCLC to evaluate PD-L1 status eligible for immunotherapy, additional biopsy specimens sampling may be needed to minimize the risk of tumor misclassification. In addition, PD-L1 qualitative IHC assays and the type of biopsy specimens related to PD-L1 expression detection.