Fig. 1

a–g illustrates the workflow and histologic processing in the study. a shows how the lesions were sectioned contiguously into tumour blocks, yielding 11 tumour blocks in this particularly case. Each red line on (a) corresponds to the specific tumour block number in Fig. 2b. Six blocks were selected randomly for further histologic processing. c and d depicts the 4-µm section stained with haematoxylin and eosin from block 2 and block 8. The black circle indicates from where the 3 mm core biopsy was performed. e illustrates a sectioned from a tissue micro array block stained for PD-L1 expression. f and g are the two cores marked with the red square in 1E and correspond the two cores in shown in c, d