Chinese Multicenter Registry for Peutz-Jeghers Syndrome

This prospective, observational patient registry will enroll approximately 1,000 individuals with a clinical or molecular diagnosis of Peutz-Jeghers syndrome (PJS) at participating hospitals in China. The registry will collect standardized clinical information, existing genetic test reports, family history, and longitudinal outcomes. The primary objective is to estimate the 10-year cumulative incidence of a first invasive malignancy after enrollment among participants without a previous malignancy or an unresolved suspected malignancy at baseline, accounting for death as a competing event. Secondary objectives address organ-specific malignancies, new primary cancers in participants with a cancer history, mortality, major polyp-related complications, and clinical and STK11 variant characteristics. Participants may be followed for up to 20 years. Biospecimen donation, additional baseline sampling, research sequencing, and patient-derived organoid studies are optional and require the corresponding consent. Refusal of an optional component does not preclude participation in the clinical registry. No treatment or clinical surveillance strategy is assigned by the study.

Inclusion Criteria: * A clinical diagnosis of PJS meeting at least one of the following: two or more histologically confirmed Peutz-Jeghers polyps; any number of Peutz-Jeghers polyps and a family history of PJS; characteristic mucocutaneous pigmentation and a family history of PJS; or any number of Peutz-Jeghers polyps together with characteristic mucocutaneous pigmentation. Alternatively, a molecular diagnosis established by a confirmed germline pathogenic or likely pathogenic STK11 variant associated with PJS, interpreted by appropriately qualified professionals. * Valid written informed consent for the core clinical registry from the participant or the legally appropriate guardian, with age- and capacity-appropriate information and assent when applicable. * Minimum clinical or genetic documentation sufficient to confirm eligibility and agreement to at least one feasible method of longitudinal contact or record-based follow-up within the approved consent. Biospecimen donation, availability of all specimen types, and participation in research sequencing or organoid experiments are not required for clinical registry enrollment. Exclusion Criteria: * Neither the clinical nor molecular diagnostic pathway can be confirmed. A variant of uncertain significance alone does not satisfy molecular eligibility. * Absence of valid consent for the core registry. Duplicate records of the same individual will be merged rather than counted as additional participants. Inability or refusal to undergo an optional sample procedure is not a registry exclusion criterion. Procedure-specific safety restrictions affect that procedure only.