Background
Population Based Cancer Registries (PBCRs) have a societal obligation to make their data available for cancer control purposes. Adopting the FAIR principles—Findable, Accessible, Interoperable, and Reusable—simplifies data sharing and promotes equal access. This approach is a key step toward realizing the European Health Data Space’s goal of pan-European data availability. Internationally, however, legal restrictions and privacy concerns may prevent registries from sharing patient-level data. Despite international initiatives to provide comparable cancer statistics through online webtools (like Global Cancer Observatory (GCO), European Cancer Information System (ECIS) and NORDCAN), PBCR-data is not used to their full potential and international collaborative research continues to be under pressure.

Objectives
The objective of this work is to provide recommendations for cancer registries on how to balance efforts to make data more accessible while adhering to best practices in data protection and privacy.

Methods
We analyze results from past and current projects aimed at either (a) improving data discoverability, metadata construction and management and data access processes (FAIR) for PBCRs or (b) facilitating data analyses via privacy enhancing technologies (PET).

Results
An overview of innovation projects is created, where FAIR technologies and/or PET are created and tested. OMOP-CDMs and metadata catalogues are deployed in routine PBCR operations. Distributed analyses are used in collaborations such as GCO, ECIS and NORDCAN, as well as in research projects like the International Cancer Benchmarking Partnership (ICBP) and have the potential to be expanded. Other initiatives, such as synthetic data and federated learning, show potential, but require higher technology readiness levels and their usage is not fully embraced yet. PET technology needs to be assisted by complementary procedures and tools for data harmonization and quality assurance. Metadata catalogues play an important part here.

Conclusions/Implications
FAIR principles and privacy-enhancing technologies enable cancer registries to share insights while adhering to data protection laws and policies. Scalable solutions like OMOP-CDM and federated analysis are ready for routine usage, while more advanced technologies need further development. Through the CancerWatch Joint Action, tools and best practices are developed to support cancer registries in promoting data usage and increasing their impact on global cancer control. European PBCRs are supported with implementation.