Schematic representation of sample collection, processing, and TCR sequencing. Four-millimeter punch biopsies were collected from early lesions (plaques; red circles) or tumors (green squares) in 27 patients with MF. Biopsies were cryosectioned and laser microdissected to capture tumor cells that were pooled together. Original magnification ×10; hematoxylin and eosin staining. DNA and RNA were isolated simultaneously from the microdissected material and processed for WES and WTS. WTS data are available only for samples MF4_2T, MF4_3P, MF5_1T, MF5_2P, MF7_1T, MF7_2P, MF11T, MF11_1P, MF19_1T, and MF19_2P and a pool of normal CD4+ lymphocytes (data not shown). The gene sequence is indicated in green, the adapter sequence is indicated in red, and the index sequence is indicated in blue.