I looked into this about a year and a half ago as I consider seeking funding to build a brain tumor registry for longitudinal follow-up. I learned that the basis of the system already exists. If you search the CDC website long enough, you will eventually find reference to
http://www.cdc.gov/cancer/npcr/training/btr/ describing PL 107-260 the Benign Brain Tumor Cancer Registries Amendment Act. So, beginning 2004, this has been done.
However, what is missing, in my opinion (which lacks a lot of humility), is the longitudinal follow-up combined with providing access to patients seeking treatment. My vision would be to not only have doctors report discovery and treatment to the CDC, but to continue to report with each each patient follow-up visit on such things as: continuing measures of treatment outcome,, patient attitude, compliance with treatment directives, additional or re-emerging symptoms, and additional treatment. On the public-facing website we would be able to view the number of patients, types of treatments, near- and long-term outcomes, by physician and facility, categorized by type, size and location of tumor.
All of this is possible, but it would add burden to physicians and would cost money and so the question is whether the potential value outweighs those items.
-Tod