Poorly differentiated follicular thyroid carcinoma: prognostic factors and relevance of histological classification.
OBJECTIVE
Poorly differentiated follicular thyroid carcinoma (PDFC) is a tumor of follicular cell origin with attributes intermediate between well-differentiated carcinomas and anaplastic carcinomas, but neither a clear histological description nor an established definition of prognostic indicators are available.


METHODS
This study correlates the clinical outcome and survival of 40 PDFC patients with histological architecture, cytological characteristics, and expression of various markers of cell proliferation and differentiation (cyclin A, cyclin B1, cyclin D1, cyclin E, Ki67, thyroperoxidase, galectin 3, dual oxidase [Duox], vascular endothelial growth factor, epidermal growth factor receptor, and p53).


RESULTS
At 5 years, the overall survival rate was 63% and the metastasis-free survival rate was 57%. An older age at the time of diagnosis and a larger tumor size were associated with an increased risk of distant metastases and of cancer-related death. Polymorph architecture was associated with a reduced risk of metastases, whereas a high expression of Duox was associated with a reduced risk of death. In these patients with PDFC, no other histological features or expression of any other marker had a prognostic significance.


CONCLUSIONS
PDFC has a more aggressive behavior than well-differentiated carcinomas; prognosis is related to indicators that are also relevant in patients with well-differentiated carcinomas.
Pulcrano
Melania
M
Nuclear Medicine and Endocrine Oncology, Commissariat à l'Energie Atomique LRC29V, Institut Gustave Roussy and University Paris Sud, Villejuif, France. mpulcrano@libero.it
Boukheris
Houda
H
Talbot
Monique
M
Caillou
Bernard
B
Dupuy
Corinne
C
Virion
Alain
A
De Vathaire
Florent
F
Schlumberger
Martin
M
D018263:Adenocarcinoma, Follicular / Q000145:classification / Q000401:mortality / Q000473:pathology*; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D012984:Software; D016019:Survival Analysis; D017741:Survivors; D013964:Thyroid Neoplasms / Q000145:classification / Q000401:mortality / Q000473:pathology*