Microscopic diseases remain in initial disseminated sites after neoadjuvant chemotherapy for stage III/IV ovarian, tubal, and primary peritoneal cancer.

Even if a disseminated site >1 cm in diameter before NACT is invisible during IDS, microscopic disease remains present within it. The appropriate surgical margins for IDS with a favorable prognosis could be secured by resecting a lesion of >1 cm before NACT even if it is invisible during IDS.