Ivana Bratic Hench

1 Introduction In many solid neoplasms, invasive cancer is preceded by pre-malignant lesions acquiring sequential molecular alterations over time. Due to the circulatory capacity of lymphocytes, this notion of precursor lesions is thought to be applicable to lymphomas only to a very limited extent. One recognized precursor state of hematologic neoplasms is the age-related phenomenon of clonal hematopoiesis of indeterminate potential (CHIP).

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Highlights • TMB is a promising predictive biomarker for immune checkpoint inhibitor response. • Many lung cancer samples are limited to cytological material. • TMB measurement on cytological smears has not been evaluated yet. • We observed robust TMB measurement in cytological smears. • Cytological smears should be preferred to formalin-fixed tissue samples. Abstract Objectives Tumor mutational burden (TMB) has emerged as a promising predictive biomarker for immune checkpoint inhibitor therapy.