A retrospective study of 17,995 patients investigating the location and recurrence of papillary thyroid cancer

The incidence of papillary thyroid cancer (PTC) has recently increased. Although PTC usually has a good prognosis, patients with advanced or localized metastases experience a high rate of recurrence. Although many studies have investigated PTC recurrence, a correlation between PTC location and recurrence remains unclear. Thus, we aimed to determine whether the location of PTC affects recurrence.Data were obtained from a single thyroid surgery center with > 6000 surgical cases per year. Between 2009 and 2022, 17,995 were enrolled in this study after screening. The location of the cancerous lesions was determined from ultrasound and pathology reports as well as the division of the lateral thyroid lobes into coronal and sagittal perspectives. The coronal plane was equally divided into upper, middle, and lower parts, and the sagittal plane was equally divided into anterior and dorsal aspects. Kaplan-Meier analysis and Cox proportional hazards regression models were used to analyze recurrence and risk factors. This study concluded that the upper part of the coronal plane and the dorsal part of the sagittal plane were most strongly associated with recurrence. Multifactorial analysis showed that lymph node metastatic status, multifocality, and superior and dorsal location of the tumor were significantly associated with PTC recurrence.