Association of tumor size and focality with recurrence/persistence in papillary thyroid cancer patients treated with total thyroidectomy along with radioactive-iodine ablation and TSH suppression.

Locoregional recurrence is common in papillary thyroid cancer PTC and an optimal surgical treatment with respect to the multifocal nature of the disease stays controversial. It is a retrospective analytical study design. 209 diagnosed PTCs managed at our institute were grouped into macro-PTC with a size of dominant focus >1 cm (unifocal n = 106 and multifocal n = 64) and micro-PTMC if size of all foci was <1 cm; (unifocal n = 16 and multifocal PTMC n = 23). The primary endpoint is recurrence and tumor free survival in each of the four groups. Secondary endpoint is an assessment of a benefit of completion total thyroidectomy in terms of assignment of true focal status to an individual's PTC. The median follow-up was 4.1 years. Upon completion thyroidectomy, the tumor focality changed to multifocal in 31.4% of macro-PTC and 60% of micro-PTMC. Multifocality was an independent risk factor for recurrence, OR 2.41 for macro (CI 1.14-5.11), and 3.48 for micro-multifocal PTMC (CI 1.19-10.2). Disease free survival patterns on Kaplan-Meier's plots were alike for micro- and macro-unifocal groups, and similarly stayed comparable among the two multifocal groups. Our analysis showed that tumor multifocality rather than size is the significant factor determining prognosis; hence, total thyroidectomy is indicated for an optimal assessment of true focality in micro-PTC.