title: Implantation of parathyroid carcinoma along fine needle aspiration track.
abstract: BACKGROUND
  Fine needle aspiration cytology is not a commonly employed diagnostic modality in the diagnosis of parathyroid tumors.
  
  
  METHODS
  A 28 year old lady being followed-up for 5 years after en bloc resection of a parathyroid carcinoma presented with a nodule in the lower neck, away from the parathyroidectomy scar. The 1 cm isolated nodule was located in the muscular and subcutaneous plane and corresponded to the needle track of FNA performed on a neck nodule before the parathyroidectomy. On evaluation, she had mild hypercalcemia and high normal serum parathyroid hormone levels. FNAC and histology including immunohistochemistry for Chromogranin A after local excision of the nodule confirmed the nodule to be a recurrent parathyroid carcinoma along the needle track.
  
  
  CONCLUSIONS
  To the best of the authors' knowledge, this is only the second case of needle track implantation after FNA in parathyroid carcinoma reported to date. This case highlights the risk of engraftment of parathyroid tissue after FNA and cautions against the use of FNA as a preoperative diagnostic modality for the evaluation of parathyroid lesions.
authors.affiliation: Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, India. gaurav@sgpgi.ac.in
authors.forename: Gaurav
authors.initials: G
authors.lastname: Agarwal
authors.forename: Sadhna
authors.initials: S
authors.lastname: Dhingra
authors.forename: Saroj K
authors.initials: SK
authors.lastname: Mishra
authors.forename: Narendra
authors.initials: N
authors.lastname: Krishnani
mesh_terms: D000328:Adult; D044963:Biopsy, Fine-Needle / Q000009:adverse effects*; D002277:Carcinoma / Q000556:secondary*; D005260:Female; D006258:Head and Neck Neoplasms / Q000556:secondary*; D006801:Humans; D009366:Neoplasm Seeding; D010282:Parathyroid Neoplasms / Q000473:pathology*