SFEBES2023 Poster Presentations Adrenal and Cardiovascular (78 abstracts)
Christian Medical College, Vellore, India
Objectives: To study the clinical, biochemical, imaging profile and treatment outcomes of patients with malignant pheochromocytoma and paraganglioma(PPGL). Also, to compare their characteristics with non-malignant PPGL to identify the factors that may predict metastasis.
Methods: This retropsective cohort study included 212 patients with PPGL managed at our centre over a period of 10 years(2013-2022). Their clinical, biochemical, radiological profile, treatment data and response were retrieved from the electronic medical records.
Results: Thirty patients had malignant PPGL and the median age at diagnosis of metastasis was 38.5 years(range10-52). 16(53.3%) patients had synchronous metastases and 14(46.7%) developed metachronous metastases after a median duration of 7.8 years(range1.1-22.5) from the diagnosis of the primary tumour. 43%(13/30) underwent genetic testing and among them 38.5%(5/13) tested positive for gene mutation related to PPGL. Median follow-up after diagnosis of metastases was 20 months(range1-96). Metastases detection rate was 100% for both 18FDG(4/4) and DOTATATE(4/4) PET-CT, 97(28/29) for CT/MRI and 78%(18/23) for I131 MIBG scan. 14(46.7%) patients received MIBG therapy. Seven patients succumbed due to metastatic disease and among them five died within a year of diagnosis of metastases, the median survival was 41 months(range13 to 83). On comparing the clinical, biochemical and imaging parameters of malignant(n=30) and non-malignant PPGL(n=182), it was found that patients with malignant PPGL had larger tumors(8.5±5vs6.2±3.3,P=0.012), had less frequent adrenergic symptoms and more often were extra-adrenal in location. On logistic regression, tumor size was found to be an independent predictor of metastases.
Conclusion: Malignant PPGLs had variable clinical course and treatment response. Although, malignant PPGL were larger compared to benign tumors, a size cut-off predicting metastases could not be derived. Majority of the patients in our cohort received MIBG therapy for metastases.