Solid variant of papillary thyroid carcinoma: incidence, clinical-pathologic characteristics, molecular analysis, and biologic behavior

Am J Surg Pathol. 2001 Dec;25(12):1478-84. doi: 10.1097/00000478-200112000-00002.

Abstract

Solid variant is a rare and poorly characterized variant of papillary thyroid carcinoma. In this study we analyzed 20 primary cases of the solid variant of papillary carcinoma found in a series of 756 papillary carcinomas operated at the Mayo Clinic between 1962 and 1989. The criteria for classification included predominantly (>70%) solid growth pattern of primary tumor, retention of cytologic features typical of papillary carcinoma, and absence of tumor necrosis. For each case of the solid variant, a control case of classical papillary carcinoma matched by age, sex, tumor size, and length of follow-up was selected. The follow-up ranged from 6 to 32 years. Two patients with the solid variant of papillary carcinoma (10%) died from disease 7 and 10 years after initial surgery, while another two patients (10%) are alive with lung metastases. In contrast, the control group had no cases with distant metastases or death from disease. Molecular analyses showed a similar prevalence of RET /PTC rearrangements in both groups. In conclusion, the solid variant of papillary carcinoma is associated with a slightly higher frequency of distant metastases and less favorable prognosis than classical papillary carcinoma. However, it should be distinguished from poorly differentiated thyroid carcinoma, which has a reported lower survival rate compared with the solid variant of papillary carcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Carcinoma, Papillary* / epidemiology
  • Carcinoma, Papillary* / genetics
  • Carcinoma, Papillary* / secondary
  • Carcinoma, Papillary* / surgery
  • Child
  • DNA Primers / chemistry
  • DNA Probes / chemistry
  • DNA, Neoplasm / analysis
  • Female
  • Follow-Up Studies
  • Gene Rearrangement
  • Genes, ras
  • Humans
  • Male
  • Middle Aged
  • Minnesota / epidemiology
  • Nuclear Receptor Coactivators
  • Oncogene Proteins / genetics
  • Oncogene Proteins, Fusion / genetics
  • Protein-Tyrosine Kinases
  • Reverse Transcriptase Polymerase Chain Reaction
  • Thyroid Neoplasms* / epidemiology
  • Thyroid Neoplasms* / genetics
  • Thyroid Neoplasms* / pathology
  • Thyroid Neoplasms* / surgery
  • Transcription Factors*

Substances

  • DNA Primers
  • DNA Probes
  • DNA, Neoplasm
  • NCOA4 protein, human
  • Nuclear Receptor Coactivators
  • Oncogene Proteins
  • Oncogene Proteins, Fusion
  • Transcription Factors
  • Protein-Tyrosine Kinases
  • ret-PTC fusion oncoproteins, human