Fig. 6
From: A practical guide to biomarkers for the evaluation of colorectal cancer

Tumor marking for molecular testing. a Well-fixed, viable, and cellular tumor areas generally yield good-quality DNA for biomarker testing. b Do not mark necrotic areas. c Avoid tumor areas with intermixed lymphocytic aggregates. d Do not use pauci-cellular/mucin-rich tumor areas if possible. Original magnification 100×