Follicular variant of papillary thyroid carcinoma: a long-term follow-up.
OBJECTIVE
The clinical behavior of the follicular variant of papillary thyroid carcinoma (FVPTC) is similar to pure papillary thyroid carcinoma (PPTC) and completely different from follicular thyroid carcinoma (FTC).


METHODS
Retrospective analysis of prospectively documented data.


METHODS
Referral center of a university hospital.


METHODS
Two hundred thirty-seven consecutive patients with follicular cell-derived thyroid carcinomas were operated on in our institution during a 15-year period, from January 1, 1980, to December 31, 1994. Of the 154 PTC patients, 37 (24%) had FVPTC. The mean follow-up was 128.2 months (10.7 years).


METHODS
Demographic features, tumor characteristics, local and distant spread, persistence or recurrence of disease, and carcinoma-related mortality were compared between the groups with FVPTC, PPTC, and non-Hürthle cell FTC (NHFTC).


RESULTS
The frequency of multicentricity was significantly higher in the FVPTC group than in the PPTC group (P =.03) or in the NHFTC group (P =.01) (12 [32%] of 37 patients vs 17 [15%] of 117 patients vs 6 [10%] of 58 patients, respectively). The incidence of cervical lymph node metastases was lower in the FVPTC group than in the PPTC group (P =.30) and higher than in NHFTC group (P =.004) (12 [32%] of 37 patients vs 53 [45%] of 117 patients vs 6 [10%] of 58 patients, respectively). At diagnosis, no patient with FVPTC showed distant metastases, compared with 5 patients (4%) with PPTC (P =.34) and 19 (33%) with NHFTC (P<.001). There was no carcinoma-related death in the FVPTC group. The strikingly poorer prognosis for the NHFTC group was statistically significant (P<.001), whereas the difference in carcinoma-specific survival between the PPTC and the FVPTC groups did show a trend toward better survival in the FVPTC group.


CONCLUSIONS
The clinical behavior of the FVPTC group did not differ significantly from that of the PPTC group, whereas compared with the NHFTC group, the FVPTC group showed statistically significant differences for most of the analyzed variables.
Passler
Christian
C
Section of Endocrine Surgery, the Division of General Surgery, Department of Surgery, University of Vienna, Medical School, Vienna, Austria.
Prager
Gerhard
G
Scheuba
Christian
C
Niederle
Barbara E
BE
Kaserer
Klaus
K
Zettinig
Georg
G
Niederle
Bruno
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018265:Carcinoma, Papillary, Follicular / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D016019:Survival Analysis; D013964:Thyroid Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D013965:Thyroidectomy; D016896:Treatment Outcome