Case 17 Answer

WetReadRad -

Answer: Retained Gallstones (aka Dropped or Spilled Gallstones) 

Complication of GB resection where gallstones are spilled into the peritoneum

 Prior - Ca+ stones in the GB 

Current - s/p cholecystectomy with stones now in the pelvis

Reference: https://radiopaedia.org/articles/retained-gallstone?lang=us