Poorly differentiated carcinomas of the thyroid with trabecular, insular, and solid patterns: a clinicopathologic study of 183 patients

Cancer. 2004 Mar 1;100(5):950-7. doi: 10.1002/cncr.20087.


Background: The term poorly differentiated (PD) carcinoma was proposed 20 years ago to define aggressive, follicular-derived thyroid carcinomas with behavior intermediate between follicular/papillary and anaplastic carcinomas. Among the variable histologic patterns recognized in such tumors, trabecular-insular-solid (TIS) areas usually are predominant. Conversely, some authors pointed out that PD carcinomas are characterized by unequivocal, high-grade histology with atypias, high mitotic counts, and necrosis rather than by a specific growth pattern.

Methods: The clinicopathologic features of a series of 183 thyroid carcinomas with predominant (n = 165 tumors) or focal (n = 18 tumors) TIS growth patterns were studied by univariate and multivariate overall survival analyses and were compared with clinical outcomes. Subgroups included tumors with predominant oxyphilic features (n = 66 tumors) and (residual) papillary carcinoma features (n = 24 tumors). Control groups of papillary (n = 68 tumors), follicular (n = 71 tumors), and anaplastic (n = 35 tumors) carcinomas also were included for overall survival analysis.

Results: TIS carcinomas had an intermediate behavior between papillary/follicular and anaplastic carcinomas (P < 0.0001). Univariate and multivariate statistical analyses demonstrated that age > 45 years (P = 0.007), the presence of necrosis (P < 0.0001), and a mitotic count > 3 per 10 high-power fields (P = 0.01) were associated with poor outcome. A simplified scoring system based on statistically significant parameters allowed the identification of three prognostic subgroups (P < 0.0001).

Conclusions: PD TIS carcinomas overall followed a more aggressive course compared with differentiated thyroid carcinomas, irrespective of the extent of the TIS component. However, a numeric scoring system applied to specific clinicopathologic parameters further may identify three prognostic categories of patients who have significantly different survival rates at 5 years and 10 years.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / mortality
  • Adenocarcinoma / pathology*
  • Adenocarcinoma / therapy
  • Adenocarcinoma, Scirrhous / mortality
  • Adenocarcinoma, Scirrhous / pathology
  • Adenocarcinoma, Scirrhous / therapy
  • Adult
  • Aged
  • Analysis of Variance
  • Biopsy, Needle
  • Carcinoma / mortality*
  • Carcinoma / pathology*
  • Carcinoma / surgery
  • Carcinoma, Papillary / mortality
  • Carcinoma, Papillary / pathology
  • Carcinoma, Papillary / surgery
  • Case-Control Studies
  • Female
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Neoplasm Staging
  • Probability
  • Prognosis
  • Retrospective Studies
  • Sex Factors
  • Survival Analysis
  • Thyroid Neoplasms / mortality
  • Thyroid Neoplasms / pathology*
  • Thyroid Neoplasms / surgery
  • Thyroidectomy / methods
  • Treatment Outcome