Table 1.

List of Other Reported Cases of Sarcomas Occurring in the Setting of Hyperparathyroidism

Case	Patient demographics	Time between hyperparathyroidism diagnosis and sarcoma diagnosis	Treatment of hyperparathyroidism	Sarcoma pathology	Sarcoma location
1 (Spiro et al)	46-year-old woman	3 years	Parathyroidectomy	Dedifferentiated chondrosarcomaa	Distal left tibia
2 (Spiro et al)	34-year-old woman	2 months	Parathyroidectomy	High-grade osteosarcoma	Mandible
3 (Mercuri et al)	56-year-old woman	Simultaneous diagnosis	Parathyroidectomy	High-grade osteosarcomab	Proximal left tibia
4 (Vassilopoulou et al & Gagel et al)	69-year-old woman	Not reported	Not reported	High-grade fibroblastic osteosarcomaa	Right proximal femur
5 (Harell et al)	50-year-old woman	3 years	Untreated	Osteosarcoma	Mandible
6 (Keen et al)	66-year-old woman	Simultaneous diagnosis	Not reported	Low-grade chondrosarcoma arising from osteochondroma	Right scapula
7 (Keen et al)	36-year-old woman	Simultaneous diagnosis	Not reported	Low-grade chondrosarcoma arising from enchondroma	Left tibia
8 (Gagel et al)	15-year-old man	Simultaneous diagnosis	Not reported	Fibroblastic osteosarcomaa	Right femur and pelvis
9 (Gagel et al)	65-year-old woman	3 years	Not reported	Fibroblastic osteosarcomab	Distal right femur
10 (our case)	22-year-old man	3 years	Parathyroidectomy	Undifferentiated pleomorphic sarcomaa	Distal right femur

^aBrown tumor or osteitis fibrosa cystica on pathology

^bBrown tumors on radiographs