Clinical Report: Overlap Between Primary Aldosteronism and Papillary Thyroid Cancer

Overview

Primary aldosteronism (PA) and papillary thyroid cancer (PTC) are both increasingly recognized conditions that may coexist more frequently than expected by chance. Recent studies suggest a higher prevalence of PA in hypertensive patients with PTC, though the association remains statistically inconclusive and requires further validation.

Background

Primary aldosteronism is found in 5% to 15% of hypertensive patients and up to 30% of those with resistant hypertension. Papillary thyroid cancer incidence has risen, largely due to increased diagnostic imaging. Both conditions are managed by endocrinologists, raising interest in potential associations. Prior research has noted increased thyroid abnormalities in PA patients and a possible link between aldosterone and malignancy prevalence.

Data Highlights

Key Findings

• PA prevalence in patients with PTC and hypertension was 29.2%, compared to 20.4% in hypertensive controls, though not statistically significant.
• Secondary analysis suggested higher PA prevalence in PTC patients when matched by hypertension stage.
• Patients with PTC and PA were younger and more likely to have the classic PTC variant.
• No association was found between PA and BRAF V600E mutation status or adrenal histology differences.
• Mineralocorticoid receptor (MR) is expressed in normal thyroid and PTC tissue, with aldosterone potentially influencing thyroid cell gene expression.
• Current evidence does not support routine screening for PTC in PA patients, but PA testing is recommended in hypertensive patients with PTC.

Clinical Implications

Clinicians should consider screening for primary aldosteronism in hypertensive patients diagnosed with papillary thyroid cancer, as PA may be underrecognized in this population. However, routine evaluation for papillary thyroid cancer in patients with PA is not currently supported by evidence. Awareness of the mineralocorticoid receptor's role in thyroid tissue may guide future research and therapeutic strategies.

Conclusion

While an association between primary aldosteronism and papillary thyroid cancer is suggested, definitive conclusions await further studies. Meanwhile, targeted PA screening in hypertensive PTC patients is a prudent clinical approach.

References

1. Maciel et al 2023 -- Higher-than-expected prevalence of primary aldosteronism in patients with papillary thyroid cancer and hypertension
2. Nakamura et al 2018 -- Incidence of primary aldosteronism in patients with papillary thyroid cancer and hypertension
3. Chinese large study 2021 -- Thyroid nodules and cancer incidence in primary aldosteronism
4. German Conn's registry study 2020 -- Malignancy prevalence in primary aldosteronism
5. Clinical nuclear receptor expression study 2015 -- Mineralocorticoid receptor in thyroid cancer
6. Manso et al 2022 -- Aldosterone effects on thyroid gene expression