Metastatic Gallbladder Cancer Presenting as Forearm Pain with Radial Bone Metastasis

Abstract Gallbladder cancer (GBC) is a relatively rare cancer associated with poor prognosis due to early direct invasion of adjacent structures and nodal metastasis. Isolated bone metastasis is rarely reported and only a few cases are available in literature. A 42-year-old female presented with forearm pain and mass for 3 months duration. She had undergone open cholecystectomy 4 years ago for cholelithiasis. Excision biopsy with decompression of posterior interosseous nerve showed metastatic adenocarcinoma deposit in bone. Fludeoxyglucose (FDG) avid soft-tissue thickening in postoperative bed along with FDG avid cortical erosion in the left occipital bone and lytic sclerotic lesion in left proximal radius was noted. The patient was started on palliative chemotherapy with gemcitabine and cisplatin. Diagnosis with GBC portends dismal prognosis due to local spread and distant metastasis. Metastasis is common to the liver and regional nodes. Isolated bone metastasis is extremely rare.