Hi Aaron,
I am not aware of any current functionality to handle two separate patient files. In fact, the metaImport script will produce an error if more than one file is marked as containing the PATIENT_ATTRIBUTES datatype.
A possible solution is to create a custom script that merges two patient data files before loading them into cBioPortal. When the survival data file is updated, you can run the script again and then use
incremental loading. This option lets you include only the rows for patients whose data has changed, which speeds up the loading process since you don't need to reload the entire file.
If you can remember more details about the study you're referencing, such as the approximate date or cancer type, I can look into it further for you.
Best,
Guizela