Malignancy risk of hyperfunctioning thyroid nodules compared with non-toxic nodules: systematic review and a...

Area of Science:

• Endocrinology
• Oncology
• Nuclear Medicine

Background:

• Hyperfunctioning (hot) thyroid nodules are generally considered low-risk for malignancy.
• Current guidelines often exclude hot nodules from further cancer risk assessment.
• This study systematically reviews and analyzes the malignancy risk in hot versus non-toxic thyroid nodules.

Purpose of the Study:

• To compare the risk of malignancy between hot thyroid nodules and non-toxic thyroid nodules.
• To evaluate the incidence and odds of cancer in hyperfunctioning nodules.
• To inform clinical guidelines regarding the management of hot thyroid nodules.

Main Methods:

• Systematic review and meta-analysis of observational studies.
• Searched Ovid MEDLINE, EMBASE, Scopus, and Web of Science databases.
• Included studies with thyroid scintigraphy, both hot and non-functioning nodules, and postoperative histopathology results.

Main Results:

• Seven studies were included in the analysis.
• Malignancy incidence in hot nodules ranged from 5-100%, versus 3.8-46% in non-toxic nodules.
• Pooled odds ratio (OR) for malignancy in hot nodules was significantly reduced (OR 0.45; 95% CI 0.31, 0.65), indicating a 55% reduction in odds, but not zero incidence.

Conclusions:

• The odds of malignancy are lower in hot thyroid nodules compared to non-toxic nodules.
• The observed incidence of malignancy in hot nodules was higher than expected.
• Further research is needed to fully understand the malignancy risk associated with hot thyroid nodules.