Various methods have been applied to measure telomere lengths. Telomere‐specific FISH facilitated our investigation of telomere lengths in distinct cell types within the tumor microenvironment at single‐cell resolution. Notable advantages of this method have been described previously 26, such as reduced nonspecific binding and more specific telomere information. The direct assessment of telomere lengths in fixed tissue samples should be valuable for validating hypotheses involving telomere shortening in tumorigenesis and progression.