One-year progression-free survival of therapy-naive patients with malignant pheochromocytoma and paraganglioma.

The natural history of malignant pheochromocytoma or paragangliomas (MPP) remain unknown. The primary aim of this study was to define progression-free survival at 1 year in therapy-naive patients with MPP. Secondary objectives were to characterize MPP and to look for prognostic parameters for progression at 1 year. The files of MPP followed up between January 2001 and January 2011 in two French Endocrine Networks were retrospectively reviewed. Therapy-naive patients were enrolled. The main outcome was progression-free survival at 1 year in therapy-naive MPP patients according to Response Evaluation Criteria In Solid Tumors 1.1 criteria. Ninety files (46 men, 44 women, mean age of 47.5 ± 15 years) were reviewed on site by one investigator. MPP characteristics were as follows: presence of an adrenal primary, a mitotic count exceeding 5 per high power field, hypertension, inherited disease, and presence of bone metastases in 50%, 22%, 60%, 49%, and 56% patients, respectively. Fifty-seven of the 90 patients with MPP (63%) were classified as therapy-naive. The median follow-up of these 57 patients was 2.4 years (range, 0.4-5.7). At 1 year, progression-free survival was 46% (CI 95: 33-59). Twenty-six of 30 (87%) patients with progression at 1 year had exhibited progressive disease at the first imaging workup performed after a median of 5.7 months. No prognostic parameter was identified. Half of the therapy-naive patients with MPP achieved stable disease at 1 year. In symptom-free patients with MPP, a wait-and-see antitumor policy seems appropriate as first line. Modality for a prospective follow-up is proposed.