To identify the preoperative risk factors for intraoperative massive blood loss in patients with abdominal pheochromocytoma and paraganglioma (PPGL).

The clinical and imaging features of 168 patients with pathologically confirmed PPGL between January 2011 and December 2021 at the First Affiliated Hospital of Naval Medical University, were retrospectively reviewed. All PPGL patients were divided into either a massive blood loss group or a non-massive blood loss group according to the blood loss in surgery. Clinical data included sex, age, body mass index, “triad” symptoms (headache, palpitation, and diaphoresis), past medical history, and taking hypertensive drugs before surgery. Imaging data included tumor location (non-adrenal or adrenal), size, number, shape (rounded or lobulated), CT attenuation values of tumor, cystic degeneration ratio, the presence of calcification, capsular invasion, vascular invasion, feeder artery, draining vein, and collateral vessel. The independent sample t test, rank sum test, and chi-square test or Fisher exact probability method were performed for statistical analyses. Multivariate logistic regression analysis was performed to identify the independent risk factors for intraoperative massive blood loss in patients with PPGL.

There were 117 patients in the non-massive blood loss group, including 57 males and 60 females. There were 51 patients in massive blood loss group, including 24 males and 27 females. There were significant differences in tumor location, size, shape, CT attenuation values of tumor in the arterial and venous phase, the presence of calcification, capsular invasion, vascular invasion, feeder artery, and collateral vessels between the two groups (P<0.05). Multivariate logistic regression analysis showed that tumor location (non-adrenal gland) [odds ratio (OR)=2.891, 95% confidence interval (CI): 1.250~6.358], tumor size (OR=1.031, 95%CI: 1.013~1.049), vascular invasion (OR=3.148, 95%CI: 1.085~9.133), and feeder artery (OR=3.036, 95%CI: 1.009~9.132) were independent risk factors for massive blood loss in PPGL surgery.

Tumor location (non-adrenal), tumor size, vascular invasion, and feeder artery are independent risk factors for intraoperative massive blood loss in patients with abdominal PPGL.