Improved quality of life in patients treated with Peptide radionuclides

Peptide receptor radionuclide therapy (PRRT) has recently been established as an important treatment modality for somatostatin receptor (SSTR)-positive tumors. The purpose of this study was to evaluate the clinical response, side-effects as well as the quality of life following ⁹⁰Y-DOTA-lanreotide (DOTALAN) and/or ⁹⁰Y-DOTA-Tyr ³-DPhe¹-octreotide (DOTATOC) therapy in patients with progressive metastatic disease during a 6-year follow-up period. Following dosimetric evaluation with ¹¹¹In-DOTALAN and ¹¹¹In-DOTATOC, 13 patients with estimated absorbed tumor doses of >5 Gy/GBq (carcinoid, n = 5; radioiodine-negative thyroid cancer, n = 4; gastrinoma, n = 1; insulinoma, n = 1; glucagonoma, n = 1; glomus jugularis tumor, n = 1) were assigned for PRRT. A dose of 925 MBq of ⁹⁰Y-DOTALAN (four patients) or 1.85–3.7 GBq of ⁹⁰Y-DOTATOC (10 patients) was administered intravenously and repeated every 4–8 weeks. Tumor dosimetry was performed prior to and under therapy, re-staging every 2–3 months. Pain intensity, Karnofsky score and general symptoms were evaluated in order to determine quality of life. Patients were followed until death. Altogether, 53 infusions of PRRT (1.85–14.1 GBq) were administered. After the first follow-up of 3 months of ⁹⁰Y-DOTALAN therapy, stable disease (SD) was observed in one patient and progressive disease (PD) in three patients. With ⁹⁰Y-DOTATOC therapy, SD was found in all 10 patients. During the re-evaluation period (4–27 months), one patient had to be shifted from ⁹⁰Y-DOTALAN to ⁹⁰Y-DOTATOC therapy due to reduced ¹¹¹In-DOTALAN uptake after 5.5 GBq. In the first 6 months after PRRT with DOTATOC, SD was found in nine of 10 patients and PD in one patient. Thereafter, SD was observed in two patients and PD in eight patients. Nine of 13 patients after PRRT with either DOTALAN or DOTATOC died. None of the patients had experienced severe acute hematological side-effects. Transient thrombocytopenia or lymphocytopenia was seen in 10 patients after 3.7 GBq, and a skin reaction in one patient. Total accumulated kidney dose ranged between 4 and 64 Gy, with reduced creatinine clearance in two patients. Pain relief was achieved in three of three patients after ~3.7 GBq ERT within 4–6 months. Appetite, weight, Karnofsky score and general well-being had improved in patients with SD during and after therapy. Based on the results of this study conducted on a small group of patients, we conclude that PRRT may offer an alternative treatment option for SSTR-positive tumors, with only mild transient side-effects and a marked improvement in the quality of life.