How would you treat progressive Rosai Dorfman Destombes disease after initial limited radiation therapy?

To provide the best answer, we need a little more detail on this case. Also, is the patient symptomatic from the abdominal disease? If not, I would observe in the short term. If symptomatic, I would do PET/CT and consider a repeat biopsy, given the risk of the development of another process. Do you ...