Individuals with germline SMADH4 or BMPR1A mutations should undergo upper and lower endoscopy from about 15 years of age to determine whether they have polyps at that time, whether these require further medical attention and to decide upon the interval of further endoscopies. In asymptomatic at-risk individuals, screening endoscopies should begin from 15 years age.
Symptomatic individuals should have upper and lower endoscopies at the time of symptomatology. If no polyps are noted, then the screening interval may be every 2–3 years of age so long as the individuals remain asymptomatic. Suggested screening for individuals with juvenile polyposis is 18-monthly colonoscopies from the mid-teens and upper GI endoscopy from 25 years (Cairns et al. 2010), but because no large trials of such surveillance have been done, the evidence supporting this recommendation is limited.
When polyps are found, they should be removed, followed by an endoscopy at 1 year. When the tract is polyp-free, then screening intervals of 2–3 years can occur. If a JPS individual presents with nonmetastatic colorectal cancer, subtotal or total colectomy should be advocated at the time of surgery. Probands or families with the clinical diagnosis of JPS but are mutation negative at both BMPR1A and SMADH4 should be managed as if they had mutation-proven JPS. Because large deletions and promoter mutations have not been systematically looked for in these 2 genes, it is possible that current “mutation-negative” JPS patients might harbor deletions and promoter mutations.