Prognostic immunohistochemical markers for small cell lung cancer: A review

Background: Small Cell Lung Cancer (SCLC) is one of the most aggressive thoracic malignancies and has been very challenging in developing personalized medicine. While immunohistochemistry (IHC) markers have established role in pathology diagnosis of SCLC, it is particularly important to apply early and simple methods to effectively determine the prognosis. This study aimed to review and identify prognostic protein markers that have potential to be incorporated into clinical care for SCLC. Methods: we systematically reviewed PubMed, Embase, Web of Science and Cochrane Library until October 19th, 2019 that reported prognostic IHC markers in SCLC. In this review, we focused on markers evaluated in at least two independent studies to compile the most forthcoming prognostic markers. Results: According to their function in the tumor, including proliferation-related markers, growth suppression related markers, invasion- and metastasis-related markers, apoptosis-related markers, angiogenesis-related markers, immune regulation-related markers. Extensive reports into informative tables based on sufficiencies of evidence were summarized as some easy-to-use literature reservoirs for further referring. Conclusions: Strong evidence supports that the 24 emerging markers or their combinations may be useful in predicting prognosis, helping personalized therapy decision-making for SCLC patients.