title: A unique RET EXON 11 (G691S) polymorphism in an Indian patient with a collision tumor of the thyroid.
abstract: BACKGROUND
  Collision tumors of the thyroid are rare, with occasional reports dealing with their genetic analysis.
  
  
  METHODS
  A 59 year old lady presented with a neck mass, associated with hoarseness of voice of 5 years duration. Radiological examination revealed nodular masses in the left lobe of her thyroid, along with one in the isthmus, extending into the right lobe and associated with enlarged neck nodes. FNAC from the left thyroid showed features of medullary carcinoma. On total thyroidectomy, 2 distinct tumor nodules were identified in the left lobe with another in the isthmus, showing features of medullary carcinoma (MTC), papillary carcinoma and follicular variant of papillary carcinoma, respectively, accompanied with nodal metastasis. Subsequently, she underwent radioablation. RET gene analysis of the patient, her 2 daughters and a grandson revealed a unique G691S polymorphism on Exon 11.
  
  
  CONCLUSIONS
  This unique case of a collision tumor of thyroid, including component of an MTC deals with the value of RET gene analysis and therapeutic implications in the index case and in family members.
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, Maharashtra, India. rekh.bharat@gmail.com
authors.forename: Bharat
authors.initials: B
authors.lastname: Rekhi
authors.forename: Rakesh R
authors.initials: RR
authors.lastname: Badhe
authors.forename: Maria Alina
authors.initials: MA
authors.lastname: Desouza
authors.forename: Devendra
authors.initials: D
authors.lastname: Chaukar
authors.forename: Anil K
authors.initials: AK
authors.lastname: D'Cruz
authors.forename: Suprita
authors.initials: S
authors.lastname: Arya
authors.forename: S V
authors.initials: SV
authors.lastname: Kane