# Active surveillance of papillary microcarcinoma

Source: https://onco.cc/technologies/active-surveillance-thyroid/  
OnCo record `active-surveillance-thyroid` (Technology). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Active surveillance watches papillary thyroid cancers of 1 cm or less with ultrasound every 6 to 12 months instead of operating, because about 90% stay stable over a decade and delayed surgery works as well when needed. It is not suitable for tumours next to the windpipe or the voice nerve, and uptake outside Japan and Korea is still low.

## Summary

Pioneered at Kuma Hospital (Japan) and Memorial Sloan Kettering: for papillary microcarcinomas (≤1 cm) without nodal or extrathyroidal disease, ~90% remain stable over a decade and delayed surgery is equally effective when needed. Endorsed by ATA guidelines; uptake outside Japan and Korea is still low. Addresses the overdiagnosis epidemic caused by ultrasound screening (South Korea's incidence rose 15-fold with no change in mortality).

## Fields

- Kind: Technology
- Status: established
- Last checked: 2026-09-07
- Principle: Serial ultrasound at 6-12-month intervals with surgery triggered by growth ≥3 mm or nodal metastasis.
- Strengths: Avoids lifelong thyroid hormone, voice and parathyroid injury for most; Cost-saving
- Limitations: Patient anxiety; requires reliable follow-up; Not for tumours near the trachea or nerve

## Sources

- Ito et al., Patient age is significantly related to the progression of papillary microcarcinoma under observation (Thyroid 2014): https://doi.org/10.1089/thy.2013.0367

## Connected records

- cancers: [Thyroid cancer](https://onco.cc/cancers/thyroid/)
- fronts: [Supportive Care & Survivorship](https://onco.cc/fronts/supportive-care/), [Surgery & Interventional](https://onco.cc/fronts/surgery/)
- technologies: [Active surveillance](https://onco.cc/technologies/active-surveillance/), [Ultrasound](https://onco.cc/technologies/ultrasound/)
- institutions: [Memorial Sloan Kettering Cancer Center](https://onco.cc/institutions/mskcc/)
- terms: [Low-risk differentiated thyroid cancer (ATA risk)](https://onco.cc/terms/low-risk-dtc/)
- ideas: [Ultrasound restraint and surveillance to reverse thyroid cancer overdiagnosis](https://onco.cc/ideas/idea-thyroid-overdiagnosis-reversal/)
- bottlenecks: [Overdiagnosis and false alarms](https://onco.cc/bottlenecks/b-overdiagnosis/)
- roadmaps: [Surgery roadmap: radical operations → less surgery → no surgery when a drug has done the work](https://onco.cc/roadmaps/surgery-roadmap/)

---
JSON: https://onco.cc/api/v1/entities/active-surveillance-thyroid.json