PDCD1 and hypothyroidism: Hypophysitis and hypothyroidism are the most common endocrinopathies seen in up to 10% of patients treated with anti-CTLA-4 and anti-PD-1/anti-PD-L1 antibodies (Weber, 2009; Hodi et al., 2010; Wolchok et al., 2010; Ibrahim et al., 2011; Topalian et al., 2012, 2014; Tarhini et al., 2012; Ribas et al., 2013b; Borghaei et al., 2015; Calabro et al., 2015; Garon et al., 2015; Larkin et al., 2015; Postow et al., 2015; Rizvi et al., 2015; Robert et al., 2015a,b; Ferris et al., 2016; Kindler et al., 2016; Nanda et al., 2016; Seiwert et al., 2016; Rosenberg et al., 2016)1.