In routine practice, no – a post-treatment biopsy is not usually needed. Unlike surgery, where pathology is used to confirm the cancer is out, with IG-SRT we rely on the clinical and imaging evidence of resolution. If at the end of treatment the area looks completely normal aside from expected redness, we don’t subject the patient to another biopsy (which would create an unnecessary wound and scar). The cure rates and our observations give us confidence that the cancer is gone.
We typically adopt a “watchful follow-up” approach: we will have you come back for periodic check-ups and if anything suspicious appears, then we’d biopsy at that time. But if everything appears fine, we do not biopsy just for the sake of it. Biopsying irradiated skin can also be a bit tricky because of changes in tissue – it might show radiation changes that can be misinterpreted if one isn’t careful, etc.
That said, if something at the end of treatment is still unclear – say there’s a small persistent bump or ulcer that we’re not sure is just healing or something residual – in those cases a biopsy might be performed to differentiate scar vs. tumor. This is not common because usually by the end of therapy, tumors are gone or dramatically reduced.
In the large majority of cases, no confirmatory biopsy is done; we let the area heal and just monitor. Remember, with IG-SRT, as the tumor dies and is absorbed, what’s left is your body’s healing tissue. Doing a biopsy on that new tissue could actually slow the healing or introduce infection unnecessarily.
So basically, if everything looks and feels normal, we declare you clinically cured without a biopsy. We rely on statistical evidence and the careful follow-up to back that up. It’s a bit of an adjustment for some patients who are used to the pathology-confirmed model of surgery. But radiation oncology works similarly for internal cancers – after radiotherapy for, say, prostate cancer, they don’t routinely biopsy the prostate; they watch PSA levels and imaging. For skin, we watch the skin.
If something doesn’t fully resolve or reappears, a biopsy will then step in to guide further action. However, given the >99% cure, doing biopsies on everyone would result in 99% of those biopsies being negative and causing needless discomfort.
So the bottom line: No, you likely won’t need a biopsy after IG-SRT unless there’s an indication (such as a doubtful area or later changes). Our follow-up exams will serve to ensure everything remains clear.
