Abstract
BACKGROUND: Small-cell lung cancer (SCLC) is a highly aggressive neuroendocrine malignancy characterized by rapid growth, early metastatic dissemination, and a dismal prognosis. For decades, treatment paradigms remained largely stagnant, particularly for extensive-stage disease (ES-SCLC). However, the last five years have witnessed a significant evolution in the therapeutic landscape. METHODS: The information for this article was gathered by synthesizing data from several key sources. This article synthesizes the evidence supporting current standards of care for both limited-stage (LS-SCLC) and ES-SCLC, incorporating data from pivotal clinical trials, a network meta-analysis of first-line chemoimmunotherapy regimens, and a critical appraisal of international treatment guidelines, and a critical analysis of international treatment guidelines from prominent organizations like the National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO). This comprehensive approach allows for a robust and well-supported summary of the current therapeutic landscape. RESULTS: For limited-stage SCLC (LS-SCLC), concurrent chemoradiotherapy (cCRT) remains the curative-intent standard, but its efficacy is now being augmented by consolidative immunotherapy, as demonstrated by the landmark ADRIATIC trial. The role of prophylactic cranial irradiation (PCI) in LS-SCLC is being re-evaluated in the era of high-sensitivity brain imaging and concerns over neurotoxicity. For ES-SCLC, the treatment paradigm has been fundamentally transformed by the integration of immune checkpoint inhibitors (ICIs) with platinum-etoposide chemotherapy, establishing a new standard of care that offers a modest but consistent survival benefit. CONCLUSIONS: The treatment of SCLC has been significantly advanced by the integration of immunotherapy, particularly for extensive-stage disease, which has established a new standard of care and improved patient outcomes. Looking to the future, the quest for predictive biomarkers and the development of novel therapeutic classes, such as Bi-specific T-cell Engagers (BiTEs) and antibody-drug conjugates, promise to build upon recent progress and offer new hope for improving the dismal prognosis associated with this disease.