Prognostic impact of tumour multifocality in thyroid papillary microcarcinoma based on a series of 160 cases

SummaryObjectiveThe objective of this study was to evaluate the prognostic impact of tumour multifocality in papillary thyroid microcarcinoma (PTMC).MethodsAll patients who underwent total thyroidectomy and central neck dissection for PTMC in our institution between 1990 and 2007 were included in this retrospective study. Statistical correlations between tumour multifocality and various clinical or pathological prognostic parameters were assessed by univariate and multivariate analyses.ResultsA total of 160 patients (133 women and 27 men; mean age: 47.8 ± 13.7 years) were included in this study. Tumour multifocality was demonstrated in 59 (37%) patients. Central neck metastatic lymph node involvement was identified in 46 (28%) patients. No statistical correlation was demonstrated between tumour multifocality and the following factors: age, gender, tumour size, extension beyond the thyroid, metastatic central neck lymph node involvement and risk of recurrence. A tumour diameter greater than 5 mm was associated with a higher risk of recurrence (P = 0.008).ConclusionTumour multifocality does not appear to have a prognostic impact in PTMC.