Rare lung cancers—2021 update on challenges, advances, and opportunities

In the diagnostic and treatment landscape of various types of lung cancer, rare tumors represent a major challenge for patient management in terms of their biology, classification, and clinical behavior. In this scenario, the term rare lung cancer refers to a multitude of heterogeneous diseases including primary pulmonary sarcoma (PPS), neuroendocrine neoplasms (NEN) of the lung, thymic epithelial tumors (TET), malignant pleural mesothelioma (MPM), and other tumors often characterized by diagnostic pitfalls, the unavailability of prognostic and predictive biomarkers, and the lack of standardized treatments. In this issue, we compiled articles on the above-mentioned rare disease and tried to elaborate clinical dilemmas and to shed some light on diagnostics, treatment, and clinical management of rare lung cancers. …