Bone, a double victim in metastatic catecholamine secreting tumors.

in Annales d'endocrinologie by Arnaud Jannin, Marie-Hélène Vieillard, George Lion, Benjamin Chevalier, Amandine Beron, Marie-Christine Vantyghem, Catherine Cardot-Bauters, Roland Chapurlat, Christine Do Cao, Stéphanie Espiard

TLDR

  • The study examined the bone density and quality of three patients with metastatic pheochromocytomas and paragangliomas and found that catecholamine excess may contribute to secondary osteoporosis and skeletal-related events.

Abstract

Benign catecholamine-secreting pheochromocytoma and paraganglioma (PPGL) can cause secondary osteoporosis. Metastatic PPGLs, often presenting with bone metastases, elevated catecholamine levels and persistent disease, may lead to more severe bone impact. We investigated bone density and quality in three cases of metastatic PPGL over long-term follow-up. Two patients had paragangliomas: a 43-year-old with an SDHB-related abdominal paraganglioma secreting norepinephrine, and a 35-year-old with an aggressive SDHA-related paraganglioma secreting both norepinephrine and dopamine. The third patient, aged 50 years, had a sporadic pheochromocytoma producing norepinephrine and dopamine. Bone mineral density (BMD) and quality were studied using dual-energy X-ray absorptiometry (DXA). The 43-year-old and 35-year-old patients exhibited lumbar and hip osteoporosis. The 43-year-old patient also showed changes in the trabecular bone score (TBS) and suffered from both osteoporotic and metastatic vertebral fractures. The 50-year-old patient had a mildly reduced hip T score but no TBS impairment. Additionally, the 35-year-old patient underwent high-resolution peripheral quantitative computed tomography (HR-pQCT), revealing a moderate decline in total BMD in the right tibia and reduced trabecular thickness in the left radius, although there were no vertebral fractures. This patient was treated shortly after diagnosis by bone resorption inhibitors, due to metastatic vertebral fractures. Impaired bone density and quality, possibly related to long-term exposure to catecholamine excess, contribute to skeletal-related events in metastatic PPGL. Recognizing these complications is important for patient management.

Overview

  • The study examined the bone density and quality of three patients with metastatic pheochromocytomas and paragangliomas (PPGLs) over long-term follow-up.
  • All three patients had elevated catecholamine levels, which may contribute to secondary osteoporosis and skeletal-related events.
  • The primary objective was to investigate the relationship between catecholamine excess and bone density and quality in PPGL patients.

Comparative Analysis & Findings

  • The study found that two out of the three patients exhibited lumbar and hip osteoporosis, with one patient also showing changes in the trabecular bone score (TBS) and suffering from both osteoporotic and metastatic vertebral fractures.
  • The third patient had a mildly reduced hip T score but no TBS impairment, although HR-pQCT revealed a moderate decline in total BMD in the right tibia and reduced trabecular thickness in the left radius.
  • The findings suggest that catecholamine excess may contribute to impaired bone density and quality, leading to skeletal-related events in metastatic PPGL patients.

Implications and Future Directions

  • Recognition of secondary osteoporosis and skeletal-related events in metastatic PPGL patients is crucial for patient management.
  • Further research is needed to investigate the mechanisms by which catecholamine excess affects bone density and quality, as well as the optimal treatment strategies for these patients.
  • Given the study's findings, treatment of bone resorption inhibitors may be considered in metastatic PPGL patients with vertebral fractures or those at high risk of developing osteoporosis.
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