Targeted Radionuclide Therapy for NETs

Eugene Woltering, MD, and colleagues evaluated the effect of sex, weight, and BMI on plasma lanreotide depot/autogel levels (abstract e15189). The study included 46 patients with NETs treated at a single clinic who had received lanreotide depot/autogel for at least 4 months. The majority of patients (89%) had switched to lanreotide depot/autogel after having an inadequate response to octreotide. Thirty-four patients (72%) received lanreotide depot/autogel 120 mg every 2 weeks, 9 patients (21%) received more than 240 mg/month, and 3 patients (7%) received less than 180 mg/month. The mean plasma lanreotide depot/autogel level in patients receiving 120 mg every 2 weeks was 8324 pg/mL. These levels ranged from 8116 pg/mL in men to 8621 pg/mL in women (this difference was not statistically significant). In an analysis adjusted for BMI, the mean lanreotide depot/autogel level was 306 pg/mL/kg/m(2); it was significantly lower in men vs women (284 vs 338 pg/mL/kg/m(2); P=.0006). The mean lanreotide depot/autogel level adjusted for body surface area was also significantly lower in men than in women, at 3740 pg/mL/m(2) vs 4810 pg/mL/m(2) (P=.004). The investigators concluded that monitoring of plasma lanreotide depot/autogel levels may be a useful guide for dosing.