TY - JOUR T1 - Association Between the Efficacy of Pembrolizumab and Low STK11/LKB1 Expression in High-PD-L1-expressing Non-small-cell Lung Cancer JF - In Vivo JO - In Vivo SP - 2997 LP - 3003 DO - 10.21873/invivo.12131 VL - 34 IS - 5 AU - TSUKASA HASEGAWA AU - NORIKO YANAGITANI AU - HIRONORI NINOMIYA AU - HIROAKI SAKAMOTO AU - TAKEHIRO TOZUKA AU - HIROSHI YOSHIDA AU - YOSHIAKI AMINO AU - SHINYA UEMATSU AU - TAKAHIRO YOSHIZAWA AU - RYO ARIYASU AU - KEN UCHIBORI AU - SATORU KITAZONO AU - ATSUSHI HORIIKE AU - MAKOTO NISHIO Y1 - 2020/09/01 UR - http://iv.iiarjournals.org/content/34/5/2997.abstract N2 - Background/Aim: STK11/LKB1 mutation has been suggested as a poorly responding candidate biomarker of the anti-programmed cell death-1 (PD-1) antibody; however, the association between STK11/LKB1 expression and the effects of anti-PD-1 antibodies is uncertain. The aim of the study was to correlate the efficacy of pembrolizumab monotherapy and STK11/LKB1 expression in untreated patients with non-small-cell lung carcinoma (NSCLC) and high PD-ligand 1 expression. Patients and Methods: From February 2017 to January 2020, we retrospectively analyzed 30 previously untreated patients with NSCLC and a tumor proportion score (TPS) ≥50% treated with pembrolizumab monotherapy. STK11/LKB1 expression in tumor tissue was evaluated by immunohistochemistry. Results: Twenty-three (76.7%) of the 30 patients were classified with low-STK11/LKB1 expression. The median progression-free survival and overall survival of patients with low-STK11/LKB1 expression was shorter than those with high-STK11/LKB1 expression, although the results were not statistically significant. The disease progression rate for the low-STK11/LKB1 group was higher than that of the high-STK11/LKB1 group. Conclusion: STK11/LKB1 expression, as measured by immunohistochemistry, could be a useful biomarker associated with the efficacy of pembrolizumab monotherapy for patients with NSCLC and a TPS ≥50%. ER -