Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2023 Jul;33(7):817-825.
doi: 10.1089/thy.2023.0076. Epub 2023 May 29.

Long-Term Outcomes of Active Surveillance and Immediate Surgery for Adult Patients with Low-Risk Papillary Thyroid Microcarcinoma: 30-Year Experience

Akira Miyauchi  1 , Yasuhiro Ito  1 , Makoto Fujishima  1 , Akihiro Miya  1 , Naoyoshi Onoda  1 , Minoru Kihara  1 , Takuya Higashiyama  1 , Hiroo Masuoka  1 , Shiori Kawano  1 , Takahiro Sasaki  2 , Mitsushige Nishikawa  3 , Shuji Fukata  3 , Takashi Akamizu  3 , Mitsuru Ito  3 , Eijun Nishihara  3 , Mako Hisakado  3 , Kazuyoshi Kosaka  3 , Mitsuyoshi Hirokawa  4 , Toshitetsu Hayashi  4
Affiliations
Observational Study

Long-Term Outcomes of Active Surveillance and Immediate Surgery for Adult Patients with Low-Risk Papillary Thyroid Microcarcinoma: 30-Year Experience

Akira Miyauchi et al. Thyroid. 2023 Jul.

Abstract

Background: It has been 30 years since the initiation of active surveillance (AS) for adult patients with low-risk papillary thyroid microcarcinoma (PTMC). This study compared the long-term oncological outcomes of patients who underwent AS or immediate surgery (IS). Methods: This is a retrospective review of extended follow-up data from patients enrolled in a single-center, prospective observational study in Japan. In total, 5646 patients diagnosed with low-risk PTMC at Kuma Hospital between 1993 and 2019 were enrolled in this study. Of these, 3222 patients underwent AS (AS group), whereas 2424 underwent IS (IS group). The patients were followed up regularly, at least once per year. Descriptive outcome data were presented according to the treatment group. Results: In the AS group, 124 patients (3.8%) had tumor enlargement of ≥3 mm, and the 10- and 20-year enlargement rates were 4.7% and 6.6%, respectively. Novel lymph node metastases occurred in 27 patients (0.8%), and the 10- and 20-year nodal metastasis occurrence rates were 1.0% and 1.6%, respectively. In the IS group, 13 patients (0.5%) experienced lymph node recurrence postoperatively, and the 10- and 20-year nodal recurrence rates were 0.4% and 0.7%, respectively. Eighteen (1.4%) of the 1327 patients who underwent hemithyroidectomy experienced recurrence in the residual thyroid. The rate of lymph node metastasis was significantly higher in the AS group than in the IS group (1.1% vs. 0.4% and 1.7% vs. 0.7% at 10 and 20 years, respectively; p = 0.009), but the differences were small. However, the proportion of patients who underwent one or more and two or more surgeries was significantly higher in the IS group than in the AS group (100% vs. 12.3% and 1.07% vs. 0.09%, p < 0.01). Distant metastatic recurrence was observed in one patient after AS and conversion surgery and another after IS; however, they were alive (18.4 and 18.8 years after diagnosis, respectively). None of the patients in this study died of thyroid carcinoma. Conclusions: Long-term oncological outcomes of patients with PTMC generally did not differ clinically significantly between those undergoing AS and IS. AS is a viable initial management option for patients with low-risk PTMC.

Keywords: active surveillance; disease progression; immediate surgery; papillary thyroid microcarcinoma; prognosis.

PubMed Disclaimer

Conflict of interest statement

No competing financial interests exist.

Figures

FIG. 1.
FIG. 1.
Patient flow diagram. Follow-up was censored in December 2022. Alive*, one patient each was alive with pulmonary metastasis; Death, all deaths were not due to thyroid cancer; Lost, lost to follow-up.
FIG. 2.
FIG. 2.
Kaplan–Meier curve of tumor enlargement rate in the AS group. AS, active surveillance.
FIG. 3.
FIG. 3.
Kaplan–Meier curve of lymph node metastasis occurrence rate in the AS group.
FIG. 4.
FIG. 4.
Kaplan–Meier curve of remnant thyroid recurrence rate in patients who underwent hemithyroidectomy in the IS group. IS, immediate surgery.
FIG. 5.
FIG. 5.
Kaplan–Meier curves of lymph node metastasis occurrence rate in the AS group and postoperative lymph node recurrence rate in the IS group.
See this image and copyright information in PMC

References

    1. Davies L, Welch HG. Increasing incidence of thyroid cancer in the United States, 1973–2002. JAMA 2006;295(18):2164–2167; doi: 10.1001/jama.295.18.2164 - DOI - PubMed
    1. Miyauchi A. Clinical trials of active surveillance of papillary microcarcinoma of the thyroid. World J Surg 2016;40(3):516–522; doi: 10.1007/s00268-015-3392-y - DOI - PMC - PubMed
    1. Ito Y, Uruno R, Nakano K, et al. . An observation trial without surgical treatment in patients with papillary microcarcinoma of the thyroid. Thyroid 2003;13(4):381–387; doi: 10.1089/105072503321669875 - DOI - PubMed
    1. Sugitani I, Toda K, Yamada K, et al. . Three distinctly different kinds of papillary thyroid microcarcinoma should be recognized: Our treatment strategies and outcomes. World J Surg 2010;34(6):1222–1231; doi: 10.1007/s00268-009-0359-x - DOI - PubMed
    1. Ito Y, Miyauchi A, Kihara M, et al. . Patient age is significantly related to the progression of papillary microcarcinoma of the thyroid under observation. Thyroid 2014;24(1):27–34; doi: 10.1089/thy.2013.0367 - DOI - PMC - PubMed

Publication types

Supplementary concepts