Introduction: Histology is a poor predictor of the malignant potential of phaeochromocytomas and paragangliomas (PPGL) and only the presence of distant metastasis confirms malignancy. This study reviews patterns of recurrence, treatment and mortality in patients with malignant PPGL presenting to our department at UCLH over 30 years.
Materials and Methods: In our series of 128 patients with PPGL, 26 (20%) with malignant tumours [male=14, mean age 43 years (571)]; eight had synchronous (5 paragangliomas, 3 phaeochromocytomas) and 18 metachronous metastases (10 paragangliomas, 8 phaeochromocytomas). There was no correlation between histology and the potential for malignant disease. The mean duration between operation and the diagnosis of metastatic disease was 38 months (22228) for paragangliomas and 78 months (11299) for phaeochromocytomas. The sites of metastases in paragangliomas were bone (9), liver (6), lung(4) and in phaeochromocytomas; liver(7), lung(6) and bone(4). Local recurrence/persistence disease was associated with distant metastasis in 18 (70%) patients.
I123-MIBG scans were avid in 6/15(40%) paragangliomas and 10/11(91%) phaeochromocytomas. Twenty-two patients received radio-targeted treatment with 131I-MIBG and/or 90Y-DOTA-octreotate/LuDO. 131I-MIBG treatment stabilized disease in 2/7(29%) paragangliomas and 7/8(87%) phaeochromocytomas. 90Y-DOTA-octreotate was associated with a much better response rate in paragangliomas, with stabilisation in 7/9 (78%) patients.
External beam radiotherapy was used in four (18%) patients who had aggressive disease with bone metastases. During the mean follow-up of 80 months (5-300), 7 patients (27%) died of recurrent disease (5 paraganglioma, 2 phaeochromocytoma).
Discussion and Conclusion: In our series 20% of patients with PPGL had malignant disease with recurrence developing earlier in patients with paragangliomas. The patterns of metastases were similar for both paraganglioma and phaeochromocytoma. One third of patients with malignant PPGL died of their disease. Strict long term follow-up is recommended for all patients with PPGL for early detection of disease recurrence.