Temozolomide treatment can improve overall survival in aggressive pituitary tumors and pituitary carcinomas

<jats:sec> <jats:title>Objectives</jats:title> <jats:p>Only few retrospective studies have reported an efficacy rate of temozolomide (TMZ) in pituitary tumors (PT), all around 50%. However, the long-term survival of treated patients is rarely evaluated. We therefore aimed to describe the use of TMZ on PT in clinical practice and evaluate the long-term survival.</jats:p> </jats:sec> <jats:sec> <jats:title>Design</jats:title> <jats:p>Multicenter retrospective study by members of the French Society of Endocrinology.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Forty-three patients (14 women) treated with TMZ between 2006 and 2016 were included. Most tumors were corticotroph (<jats:italic>n</jats:italic> = 23) or lactotroph (<jats:italic>n</jats:italic> = 13), and 14 were carcinomas. Clinical/pathological characteristics of PT, as well as data from treatment evaluation and from the last follow-up were recorded. A partial response was considered as a decrease in the maximal tumor diameter by more than 30% and/or in the hormonal rate by more than 50% at the end of treatment.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>The median treatment duration was 6.5 cycles (range 2–24), using a standard regimen for most and combined radiotherapy for six. Twenty-two patients (51.2%) were considered as responders. Silent tumor at diagnosis was associated with a poor response. The median follow-up after the end of treatment was 16 months (0–72). Overall survival was significantly higher among responders (<jats:italic>P</jats:italic> = 0.002); however, ten patients relapsed 5 months (0–57) after the end of TMZ treatment, five in whom TMZ was reinitiated without success.</jats:p></jats:sec> <jats:sec> <jats:title>Discussion</jats:title> <jats:p>Patients in our series showed a 51.2% response rate to TMZ, with an improved survival among responders despite frequent relapses. Our study highlights the high variability and lack of standardization of treatment protocols.</jats:p> </jats:sec>