Does surgical treatment improve diabetes in pheochromocytoma patients? A comparative study before and after tumor resection in a series of 23 patients

Objective: The present study aimed to assess the prevalence of diabetes in a cohort of pheochromocytoma patients registered at the Pathology Departments of two County Hospitals. Additionally, diabetes status was re-evaluated following tumor resection to determine whether surgery had an impact on improving or alleviating the condition.
Methods: We performed a retrospective study including all patients who underwent adrenalectomy and were diagnosed with pheochromocytoma based on histopathological findings in Mureș County (2017-2022) Hospital and Mureș County Emergency (2000-2022), Romania, respectively. All patients that were alive and whose contact details were available, participated in a phone survey and provided clinical data. Information on the presence of diabetes at the time of pheochromocytoma diagnosis and their diabetes status after tumor resection was recorded. The follow-up period ranged from 24 to 216 months.
Results: We identified 35 patients with a histopathological diagnosis of pheochromocytoma. Complete histopathological and clinical data were obtained for 23 patients; 13/23 (56.5%) were women and 10/23 (43.59%) were men; the mean age at surgery was 52.73 ±14.22 years-old (range 24-78). Of these, eight patients (n=8/23; 34.7%) were diagnosed with diabetes prior to surgery. All diabetic patients showed improvements in their carbohydrate metabolism and 5 (62.5%) of them revealed a restored normal glucose tolerance after surgery.
Conclusions: Our study highlights that overt diabetes mellitus is present in more than one-third of patients with pheochromocytoma. Tumor removal improves dysglycemia in all diabetic pheochromocytoma patients and cures diabetes in a significant proportion of them.