A protocol for a Canadian prospective observational study of decision-making on active surveillance or surgery for low-risk papillary thyroid cancer

IntroductionLow-risk papillary thyroid cancer (PTC) is increasingly being diagnosed throughout the world; yet the mortality risk is low compared with other malignancies. Traditional management includes thyroid surgery, sometimes followed by radioactive iodine and thyroid hormone treatment. Active surveillance (AS) has been proposed as a means to reduce overtreatment of PTC. AS involves close disease follow-up, with the intention to intervene if the disease progresses, or on patient request.Methods and analysisThis is a multiphase prospective observational study. In the first phase of this study, consenting eligible adults with low-risk PTC, that is,