Emerging viral pathogens, particularly those targeting the respiratory system such as SARS-CoV-2 and influenza virus, pose significant challenges for patients with lung cancer. These patients show increased susceptibility to serious infections caused by these viruses as a result of immunosuppression from various therapies such as immunotherapy, chemotherapy, and targeted agents. Respiratory viral infections can induce tumor progression and drug resistance through affecting the tumor microenvironment (TME), modulating immune checkpoints, or interfering with therapeutic efficacy. The present review discusses the reciprocal interactions between these viral pathogens and lung cancer, underscoring mechanisms by which SARS-CoV-2 and influenza viruses affect the lung cancer TME promoting tumor progression, immune evasion, and ultimately, resistance to anti-cancer therapies such as tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs). Sections discussed in this study include: (i) increased susceptibility to viral infections, (ii) virus-induced modulation of the tumor microenvironment, and (iii) mechanisms of therapy resistance. This review also addresses emerging strategies, such as oncolytic virotherapy, as potential candidates for lung cancer treatment. It aims to provide new perspectives on therapeutic optimization for patients with lung cancer in the context of SARS-CoV-2 and influenza viruses, by reviewing evidence from virology, oncology, and immunology.Copyright © 2025. Published by Elsevier Ltd.