Would you recommend SBRT in the adjuvant settings for a solitary metastasis focus in the abdominal wall resected to R1 in a young and healthy patient with clear cell ovarian cancer?

If it is truly an R1 resection, I would observe and follow with close imaging.

If she recurs, I would recommend a discussion for systemic therapy. If she has persistent disease that is amendable to SBRT, it is reasonable to treat. SBRT can prolong a chemotherapy holiday and dosing in the pelvis is usually limited by proximity of GI OARS. Lazzari et al., PMID 29893277

That depends on the systemic disease status, platinum eligibility, and prior radiation as well as proximity to nearby bowel. 90% of insurers won't cover SBRT without very compelling reasons to (prior disease, no systemic options remaining, etc etc) so outside of a few select institutions, in most places it wouldn't be paid for.

I most likely would challenge with next line systemic therapy and if no progression beyond that area, radiate with a more conventional fractionation knowing that the p...

This would be reasonable to proceed with observation. If this is recurrent disease, I would do systemic and close monitoring and treat if suspected recurrence.

I don’t think strictly wrong either though to treat if the target is clear, and no luminal GI nearby.

Would not treat with adjuvant RT in what is presumably a port-site metastasis. If the patient recurs in a limited fashion, treat at the time of gross disease.

Whether the patient requires systemic therapy now (versus at the time of future recurrence) would be worth a discussion. I would personally favor monitoring and reserving chemotherapy at the time of non-limited tumor recurrence.

I am not aware of any evidence to recommend adjuvant SBRT and I would not treat this patient even if R1 resection, what I presume is a port site recurrence.

The patient's systemic options need to be considered in this case if any. If ok to be not on any systemic therapy, then I would recommend observation only, as there is a risk of recurrence not only locally, but distantly.

Depending on recurrence I would treat the patient with SBRT if gross disease is present, especially if prolonged system...