POLD1 and central nervous system cancer: POLE/POLD1 pathogenic variant or POLD1 pathogenic variant and MMR deficiency-associated mutational signatures SBS10 and SBS20 were detected in 6/14 (43%) cases, including the hypermutated spinal metastases of patients Fam011-III.1/M1 (contribution of mutational signatures SBS10/SBS20: 21%) and patient M2 (7%), and the primary gliomas of patients WI161-II.1 (14%), WI140-III.1 (11%), WI104-III.1 (4%), and M2 (8%) (Fig. 3b).