Extremely Rapid Response to Pembrolizumab in a SMARCA4 Mutant PD-L1 Highly Expressive Advanced Lung Adenocarcinoma: A Case Report

Author Info

Xiuming Zhu Hongming Pan Lili Liu

Corresponding Author

Lili Liu
Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China

A B S T R A C T

SMARCA4 mutant non-small cell lung cancer (SMARCA4m-NSCLC) has a poor prognosis owing to rapid growth. Effective treatments for SMARCA4m-NSCLC have not yet been established. Recently, many preclinical studies support the hypothesis that SMARCA4m-NSCLC may be vulnerable to immune checkpoint inhibitors. Here, we report a patient with programmed death-ligand1 (PD-L1) highly expressive SMARCA4m-NSCLC who showed an extremely rapid and long-term response to pembrolizumab. He was referred to our hospital for a mass of the right lung. Positron emission tomography-computed tomography showed right lung tumor, hilar, mediastinal and bone metastases. Pathological and immunohistochemical results showed it was a lung adenocarcinoma and revealed the tumor proportion score of PD-L1 was 80%. SMARCA4 and K-RAS genes were co-mutations. BRG1 protein expression was negative. Subsequently, pembrolizumab treatment as the first line of therapy was commenced for the patient. With only one dose, pembrolizumab significantly inhibited tumor growth and a partial response was obtained. To date, pembrolizumab treatment has been continued for about 29 months. Severe immune-related adverse events were not observed. Our case showed that an extremely rapid and long-term response can be achieved with pembrolizumab for PD-L1 highly expressive SMARCA4m-NSCLC. Immune checkpoint inhibitors treatment may be a promising strategy for PD-L1 positive SMARCA4m-NSCLC.

Article Info

Article Type

Case Report

Publication history

Received: Tue 31, Aug 2021
Accepted: Wed 20, Oct 2021
Published: Fri 05, Nov 2021

Copyright

© 2023 Lili Liu. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Hosting by Science Repository.
DOI: 10.31487/j.SCR.2021.11.07