title: Tumor-to-tumor metastasis: Hepatocellular carcinoma metastatic to parathyroid adenoma.
abstract: Tumor-to-tumor metastasis is a rare, but well-recognized phenomenon. Here, we report a unique case of hepatocellular carcinoma (HCC) metastatic to parathyroid adenoma. A 53-year-old-man with a history of HCC presented with hypercalcemia. It was found that he also had hyperparathyroidism with a hypoechoic mass in the lower portion of the right thyroid gland area. The patient underwent parathyroidectomy, and a mass measuring 1.5 × 1.0 cm was detected. Microscopic and immunohistochemical examination disclosed parathyroid adenoma with a focus of metastatic HCC. For the patient, it was the only distant metastasis revealed until the last follow-up. To the best of our knowledge, this is the first reported case of tumor-to-tumor metastasis in which HCC is the donor.
authors.affiliation: Department of Pathology, Seoul National University Hospital Department of Pathology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hee Eun
authors.initials: HE
authors.lastname: Lee
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Kim
authors.forename: Young Hye
authors.initials: YH
authors.lastname: Cho
authors.forename: Kyungeun
authors.initials: K
authors.lastname: Kim
authors.forename: Seoung Wan
authors.initials: SW
authors.lastname: Chae
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Sohn
mesh_terms: D000236:Adenoma / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000556:secondary*; D017115:Catheter Ablation / Q000379:methods; D016461:Chemoembolization, Therapeutic / Q000379:methods; D006801:Humans; D033162:Incidental Findings; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010282:Parathyroid Neoplasms / Q000378:metabolism / Q000556:secondary* / Q000628:therapy; D016105:Parathyroidectomy