Long-Term Complete Response of Advanced Lung Squamous Cell Carcinoma in an Elderly Patient Treated with First-Line Anti-PD-1 Antibody Monotherapy: A Case Report

Abstract

Introduction and importance:Lung cancer is extremely difficult to treat due to its high incidence and mortality rate. Immune checkpoint inhibitor therapy is a major breakthrough in the field of oncology and is an emerging anti-tumor treatment modality after chemotherapy, targeted therapy and anti-angiogenic therapy. However, patients with complete response were also noticed as an anecdote especially in the aged. Here we presented a non-small cell lung cancer case who benefited from treatment of anti-PD-1 antibody.Case presentation: An 80-year-old male was admitted, presenting with a intermittent cough and a small amount of blood in the sputum for 2 months, computed tomography showed a lesion in the right lung. Lung puncture biopsy results suggested lung squamous cell carcinoma. Wild-type epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) were showed in the tumor tissue specimen. Antiprogrammed death 1 (PD-1) antibody monotherapy was initiated for 13 cycles. After the first anti-PD-1 antibody treatment, cryotherapy was performed under tracheoscopy on the mucosal bulge of the right principal bronchus and the root of the right upper lobe bronchial neoplasm. Complete remission (CR) was confirmed via imaging before the 3rd cycle. Subsequent CT suggested stable disease conditions. The presence of CR was further confirmed through a Positron Emission Computed Tomography (PET)/CT test in the 13th cycle. The patient now experienced a long-term complete response of more than 4 years till now.Clinical Discussion: Lung cancer has the highest morbidity and mortality in China. Immune monotherapy has become the standard first-line treatment for patients with upregulated expression of programmed death-ligand 1 (PD-L1). The effect of immunotherapy is similar and equally safe in older and younger patients with lung cancer. Monotherapy has the potential to achieve rapid lesion regression in elderly lung cancer patients, and the presence of immunological memory in T lymphocytes may be responsible for long-term response of the tumor lesions. Conclusion:We reported a long-term complete response of advanced lung squamous cell carcinoma in aged treated with first-line anti-PD-1 antibody monotherapy. More studies are needed to evaluate the efficacy and safety of immune checkpoint inhibitors in the aged.