The Neuro foundation in the UK has recently been asked by NICE if it would like to nominate specialists in neurofibromatosis for a guideline on paediatric pituitary adenoma. The is presumably because a publication search has resulted in a potential association. A review from 2016 substantiates this but evidence is based mainly on a small number of case reports starting on 1964 from France. Taken a current population of Europe and North America of around 1.1 billion there will currently be close to 300,000 with NF1. With a lifetime risk of 0.27% in the general population 780 of these might be expected to develop a PA by chance. A few case reports is therefore hardly Causal evidence. In the highly specialised English NF1 service that covers a population of about 14, 000 nf1 patients we have seem no evidence for an increase. Unless anyone out there has good epidemiological evidence for an association it is important to prevent a guideline stating that children should be considered for nf1 if they have a Pa. Otherwise parents of the 20% with one or two cafe au lait patches will be frightened by being referred to am expert for consideration of having nf1. It is really important that associations of not uncommon conditions in case reports are not over interpreted as Causal and that association is based on proper Epidemiology. Even this may produce a spurious false positive as nf1 patients are more likely to have an asymptomatic tumour picked because of increased likelihood of getting a cranial MRI scan.