Clinical and genetic features of older patients with pheochromocytomas and paragangliomas: A multicenter...

The genetic background and catecholamine phenotype of pheochromocytomas and paragangliomas (PPGLs) influence the age at diagnosis. However, few studies have systematically investigated clinical features of older patients with PPGLs. This study was based on one of the largest PPGL cohorts in China and aimed to summarize the clinical and genetic characteristics of older PPGL patients, especially concerning intraoperative hemodynamics and genetic background.

This retrospective study involved 897 patients with abdominal PPGLs from two Chinese centers. DNA from tumor samples was sequenced using next-generation sequencing. Clinical information, intraoperative hemodynamic data, and pathogenic variants were collected and compared between younger (≤ 50 years) and older (> 50 years) patients.

Older patients had a higher rate of incidental tumors (40.5% vs. 48.2%, P = 0.022), fewer typical catecholamine-related symptoms (49.8% vs. 42.4%, P = 0.032), lower plasma normetanephrine levels (7.61 vs. 5.17, P = 0.003) and higher proportion exceeding the normal glycemic range (21.7% vs. 34.4%, P = 0.01) compared to younger patients. The proportion of older patients receiving α-adrenergic receptor blockers for preoperative preparation decreased to 74% compared to 82.4% in younger patients (P = 0.003). During surgery, older patients showed hemodynamic changes indicative of vascular and cardiac aging. Specifically, older patients had lower minSBP, DBP, minMAP, and heart rate, while the SBP fluctuation was higher (P = 0.008). Additionally, younger patients have significantly higher mutation rates for SDHB (5.5% vs. 1.0%, P < 0.001) and VHL (13.3% vs. 7.3%, P = 0.003). HRAS mutations are more prevalent in older patients (10.5% vs. 21.3%, P < 0.001). IDH1 mutations occurred exclusively in older patients (0.56%, 5/887).

Older patients with PPGLs have unique clinical and genetic characteristics. These differences highlight the importance of personalized diagnosis and treatment for various age groups, particularly in developing preoperative preparation strategies to improve vascular and cardiac function in older patients.