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.
Keywords: Micro-papillary thyroid cancer; Multifocal papillary; Recurrence free survival; Thyroid cancer; Tumor recurrence.