Management of Low-Risk Thyroid Cancers: Is Active Surveillance a Valid Option? A Systematic Review of the Literature

Abstract

Thyroid cancer is the most common endocrine malignancy, representing 2.9% of all new cancers in the United States. It has an excellent prognosis, with a five-year relative survival rate of 98.3%.Differentiated Thyroid Carcinomas (DTCs) are the most diagnosed thyroid tumors and are characterized by a slow growth rate and indolent course. For years, the only approach to treatment was thyroidectomy. Active surveillance (AS) has recently emerged as an alternative approach; it involves regular observation aimed at recognizing the minority of patients who will clinically progress and would likely benefit from rescue surgery. To better clarify the indications for active surveillance for low-risk thyroid cancers, we reviewed the current management of low-risk DTCs with a systematic search performed according to a PRISMA flowchart in electronic databases (PubMed, Web of Science, Scopus, and EMBASE) for studies published before May 2021. Fourteen publications were included for final analysis, with a total number of 4830 patients under AS. A total of 451/4830 (9.4%) patients experienced an increase in maximum diameter by >3 mm; 609/4830 (12.6%) patients underwent delayed surgery after AS; metastatic spread to cervical lymph nodes was present in 88/4213 (2.1%) patients; 4/3589 (0.1%) patients had metastatic disease outside of cervical lymph nodes. Finally, no subject had a documented mortality due to thyroid cancer during AS. Currently, the American Thyroid Association guidelines do not support AS as the first-line treatment in patients with PMC; however, they consider AS to be an effective alternative, particularly in patients with high surgical risk or poor life expectancy due to comorbid conditions. Thus, AS could be an alternative to immediate surgery for patients with very-low-risk tumors showing no cytologic evidence of aggressive disease, for high-risk surgical candidates, for those with concurrent comorbidities requiring urgent intervention, and for patients with a relatively short life expectancy.

CACA guidelines for holistic integrative management of thyroid cancer

“…AS has been associated with many issues in clinical practice: (1) In most cases, microcarcinoma progresses slowly during AS, but some patients will have tumor progression, lymph node metastasis, and even distant metastasis, resulting in adverse consequences such as an expanded surgical scope. Younger age and pregnancy are potential risk factors for tumor progression [290][291][292][293]. AS has certain risks due to a lack of effective methods to identify true low-risk patients.…”

Ubiquitin‐specific peptidase 10 attenuates the ferroptosis to promote thyroid cancer malignancy by facilitating GPX4 via elevating SIRT6

“…are common predisposing factor that triggers this disease 3 . The 5‐year survival rate of well‐differentiated THCA is as high as 98.3% 4 . However, approximately 20% THCA cases encounter local recurrence and about 10% suffer from distant metastases, such as lung metastases and bone metastases 5 .…”

“…3 The 5-year survival rate of welldifferentiated THCA is as high as 98.3%. 4 However, approximately 20% THCA cases encounter local recurrence and about 10% suffer from distant metastases, such as lung metastases and bone metastases. 5 Radioactive iodine therapy is the common method for advanced THCA patients.…”

Epithelial‑to‑mesenchymal transition of circulating tumor cells and CD133 expression on predicting prognosis of thyroid cancer patients

“…Normally, the overall prognoses of PTC and FTC are excellent. The overall 5-year survival rate is 85% for women and 74% for men at stages I-III, respectively (10,11). By contrast, patients with stage IV thyroid cancer and anaplastic thyroid cancer have a poor prognoses (11,12) because these patients with advanced thyroid cancer or low differentiated thyroid cancer do not respond to surgery or insensitive to radioactive iodine-131 treatment (13).…”