SDHB and neoplasm: The questionnaire in the first round included 47 open questions (Supplementary Table S1) on initial and follow-up tumour screening in asymptomatic mutation carriers for each of the four genes (SDHA, SDHB, SDHD and SDHC), including the minimum age for offering predictive genetic testing and thus initial screening as well as the biochemical and imaging tests to be used for initial and follow-up tumour screenings.