There're likely to be some structural issues with human neurology - things like Alzheimers, but software-level bit rot or overfitting instead of physical failure - that will need to be addressed as part of immortality science. For example, we'll likely need to tweak our brains' hard-coded exploration/exploitation tuning so people don't end up stagnating or ossifying and not being able to appreciate the future. Trauma is somewhat related here; suicide, and the mental health issues that lead to it, is just as valid immortality-research topics as cancer and general senescence.

Summary: "Immortality" isn't just anti-aging. Mental health and intellectual extensibility are just as important to immortality as oncology.