Metastatic phaeochromocytomas and paragangliomas are very rare neuroendocrine cancers that occur in <1 per million individuals. A variety of treatment modalities have been used to manage these cancers, but with limited success and based on weak evidence. Now, the results of FIRSTMAPPP — probably the first randomized trial in this setting — demonstrate the efficacy of sunitinib.

Owing to the potentially indolent course of malignant phaeochromocytomas and paragangliomas, this academic phase II trial enrolled patients with documented tumour progression ≤18 months after the diagnosis of metastatic disease. A total of 78 patients, most of whom had received prior systemic therapy (60%), were enrolled at 14 centres across Europe over a period of 7 years and were randomly assigned (1:1) to receive sunitinib or placebo. The primary end point was 12-month progression-free survival (PFS), assuming an improvement from 20% to 40%. Although randomized, the trial was non-comparative, with the placebo control arm included to confirm that the 12-month PFS without active treatment is 20% (within the 90% CI).