title: High index of clinical suspicion with optimal surgical techniques and adjuvant radiotherapy is critical to reduce locoregional disease progression in parathyroid carcinoma.
abstract: OBJECTIVE
  We have analyzed the risk factors and the impact of external beam radiotherapy (EBRT) in reducing the locoregional recurrence of parathyroid carcinoma (PTC).
  
  
  METHODS
  Various parameters such as clinical presentation, intraoperative findings, surgical methods, and usage of parafibromin were analyzed. Selected endpoints were locoregional progression-free survival and overall survival.
  
  
  RESULTS
  Three patients had local recurrence. Two of them received EBRT after the first recurrence but continued to have local recurrence. One patient was lost to follow-up. Six patients with EBRT remain asymptomatic with a locoregional progression-free survival and overall survival of 42 months. The presence of a palpable nodule in the neck, serum calcium >14 mg/dL, and intraoperative substrap adhesion (OR=9.3, 95% confidence interval, 1.76-56.1; P<0.05) should raise suspicion. Four of 5 patients showed a predominantly negative staining with parafibromin.
  
  
  CONCLUSIONS
  PTC should be suspected in the preoperative and intraoperative period. EBRT may reduce local recurrence by 65%. Parafibromin staining with no more than 0 to 1+ intensity in 80% to 100% of cells can predict carcinoma with specificity up to 100%.
authors.affiliation: Department of Endocrine Surgery, Christian Medical College, Vellore, India. drckben@gmail.com
authors.forename: Ben
authors.initials: B
authors.lastname: Selvan
authors.forename: Mazhuvenchery J
authors.initials: MJ
authors.lastname: Paul
authors.forename: Mandalam S
authors.initials: MS
authors.lastname: Seshadri
authors.forename: Nihal
authors.initials: N
authors.lastname: Thomas
authors.forename: Thomas
authors.initials: T
authors.lastname: Paul
authors.forename: Deepak
authors.initials: D
authors.lastname: Abraham
authors.forename: Regi
authors.initials: R
authors.lastname: Oommen
authors.forename: Nylla
authors.initials: N
authors.lastname: Shandhly
authors.forename: Subhashini
authors.initials: S
authors.lastname: John
authors.forename: Simon
authors.initials: S
authors.lastname: Rajaratnam
authors.forename: Marie M
authors.initials: MM
authors.lastname: Therese
authors.forename: Aravindan
authors.initials: A
authors.lastname: Nair
authors.forename: Prasanna
authors.initials: P
authors.lastname: Kumar Samuel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D010282:Parathyroid Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D012307:Risk Factors; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C454900:CDC73 protein, human; D025521:Tumor Suppressor Proteins