Management of malignant phaeochromocytoma: A retrospective review of the use of MIBG and chemotherapy in the West Midlands

Metastatic malignant phaeochromocytoma is a rare disorder, with no randomiz ed and few prospective data to facilitate choice between the two main treat ment modalities, chemotherapy and radiolabelled metaiodobenzylguanidine (MI BG). In the last decade the latter modality has been preferred and radiolog ical response rates of 30% have been reported. There are fewer patients des cribed in the literature who have received chemotherapy but one prospective trial of chemotherapy reported radiological response rates of 57%. A recen t prospective trial combining the two modalities has been disappointing wit h only one patient completing the treatment schedule. We present six patien ts with malignant phaeochromocytoma or paraganglioma who received MIBG ther apy. Four patients also received chemotherapy. A retrospective review of the case notes was performed. Radiological and ho rmonal responses were determined and the time to progression after each mod ality was calculated. One partial hormonal response was seen with MIBG trea tment. One complete and one partial hormonal response and one partial radio logical response were seen with chemotherapy. The median time to disease, p rogression from commencement of MIBG was 12 months (range 3-44) and from co mmencement of chemotherapy used as first or second line treatment was 22.5 months (range 7-25). Chemotherapy may be a more active modality in this disease than previously considered. MIBG uptake may increase after a partial radiological response to chemotherapy, enabling Subsequent MIBG therapy. Researchers carrying out future trials on combined therapy should consider administering chemothera py prior to MIBG for the reasons that we outline in this article.