Endocrine Abstracts

Introduction: Malignant pheochromocytomas present a real challenge for practitioners. This entity of tumors is rare, with complex characterization, and heterogenocity in their evolution and prognosis. Given the rarity of this tumor group, there is no consensus on the therapeutic management. The management must be in a multidisciplinary framework. Through this illustrative case, we propose a literature review of this rare entity with discussion of the different therapeutic options in a metastatic situation.

Observation: A 23-year-old patient, with no pathological history, admitted for etiological assessment of a right adrenal mass revealed by isolated right low back pain evolving 5 years previously. An ultrasound was carried out having objectified two tissue masses of the liver of secondary appearance, then a complement by an adrenal scan objectified a voluminous tumoral process at the right adrenal, very vascularized seat of a zone of necrosis with liver metastases. Methoxylates were negative, urinary free cortisol was normal, and dexamethasone suppression test was positive. The patient underwent a right adrenal-nephrectomy complicated by renal failure due to tubular necrosis. The anatomopathological study was in favor of a pheochromocytoma. Bone scintigraphy revealed humeral metastases. As part of a multidisciplinary decision, chemotherapy (CVD), metabolic radiotherapy and treatment with iodine 131 MIBG were proposed. The patient is currently being monitored in France, since she was admitted there for doctoral studies. The 1-year follow-up after surgery showed a reduction in the volume of hepatic metastases, as well as an improvement in renal function with clinical and radiological monitoring as a therapeutic option.

Discussion/Conclusion: Malignant pheochroocytomas represent 10 to 15%. They are defined by the presence of metastases at sites devoid of chromaffin. In the absence of curative treatment and the presence of long survivors, monitoring may be a therapeutic option. The treatment is justified by the presence of a large tumor volume, the presence of an uncontrollable hormonal syndrome and radiological progression. Cytoreductive surgery should reduce symptoms and improve response to other treatments.For slowly progressive metastatic pheochromocytomas, treatment with 131I-MIBG has been recommended as first-line treatment, with 177Lu-DOTATOC being a potential alternative for those with positive somatostatin receptor metastases; chemotherapy combining Dacarbazine, Vincristine and Cyclophosphamide, may be considered for progressive disease. Prospective trials, in terms of targeted therapies, are necessary for a better characterization of these tumors in order to identify the appropriate treatment. The prognosis of theses tumors remains unfortunate.