Clinico‐pathologic prediction of malignancy of thyroid follicular lesion with FNAC‐A multivariate analysis

Abstract

Background: Patients suffering thyroid nodules with the diagnosis of follicular lesion on FNAC normally undergo thyroidectomy as the diagnosis of follicular carcinoma can only be ascertained by histopatholoigc examination. We undertake this study to examine the likelihood of various preoperative clinicopathologic parameters to predict malignancy. Methods: All the patients presented with thyroid nodules with follicular lesion diagnosed by FNAC were retrospectively evaluated if they have undergone thyroidectomy. The final histopathologic diagnoses were the gold standard. The clincopathologic parameters studied encompassed: gender, age, previous thyroidectomy, enlarging nodule, nodule size, presence of symptom, incidental finding, presentation duration, presence of Hurthle cell, cytological atypia and colloid content. The statistical analysis was carried out by SSPS 11.0 software. P‐value <*Τ*0.05 was considered statistically significant. Results: A total of 354 thyroidectomies have been carried out from January 1998 to December 2003. Sixty‐seven patients satisfied the inclusion criteria. The mean age was 51.3 ± 15.4 years old. There were only eight male patients. The final histopathologic results were: hyperplastic nodule (n = 32), follicular or Hurthle cell adenoma (n = 22), follicular carcinoma (n = 3), Hurthle cell carcinoma (n = 3), papillary carcinoma (n = 4), medullary carcinoma (n = 1) and two cases of Hashimotos thyroiditis. On univariate analysis, nodule enlargement and cytological atypia were found to be significant predictors of malignancy. (Table) However, only the nodule enlargement remained significant on multivariate analysis. (P=0.048) Sex (M vs F)NSAge (<50 vs >/50 year)NSPrevious thyroid surgery (Yes vs No)NSEnlarging nodule (Yes vs No) P=0.024Nodule size (<3 vs >/=3 cm)NSSymptoms (Yes vs No)NSIncidental finding (Yes vs No)NSPresentation duration (<2 vs >/=2 year)NSHurthle cell (Yes vs No)NSCytological atypia (Yes vs No) P=0.046Colloid content (Yes vs scanty/nil)NS Conclusion: Enlargement of thyroid nodules with follicular lesion diagnosed by FNAC significantly associate with malignancy. This category of patients should receive early thyroidectomy.