Endocrine Abstracts (2009) 20 P203

Efficacy and safety of 90Y-DOTATATE therapy in neuroendocrine tumours (NETs)

Anna Sowa-Staszczak1, Alicja Hubalewska-Dydejczyk1, Jolanta Kunikowska2, Leszek Królicki2, Renata Mikolajczak3, Dariusz Pawlak3, Aleksandra Gilis-Januszewska1, Malgorzata Trofimiuk1 & Agnieszka Stefanska1

1Nuclear Medicine Unit, Endocrinology Department, Medical College, Jagiellonian University, Krakow, Poland; 2Nuclear Medicine Department, Medical Academy, Warsaw, Poland; 3Research and Development Department, IAE Radioisotope Centre POLATOM, Otwock-Swierk, Poland.

Therapy with labeled somatostatin analogues is the modern approach to patients with disseminated or unresectable NETs expressing somatostatin receptors (SSTR). Octreotate is the somatostatin analogue with high affinity to SSTR type 2, most commonly present in NETs. The aim of the study was to assess the efficacy and toxicity of peptide receptor radionuclide therapy (PRRT) with the use of 90Y labelled Tyr3-octreotate, (90Y-DOTATATE) in NETs.

Material: Thirty-six patients with positive 99mTc-Hynic-Tate receptor scintigraphy (23 females, 13 males; Karnofsky’s index >70–83%, <70–17% of the patients) were referred to the therapy. The study group comprised 22 patients with foregut, 11 with midgut, 2 with hindgut tumours, 1 with NET of unknown origin and 3 patients with unresectable tumour, but no metastases.

Methods: Each patient received 7.4 GBq/m2 (200 mCi/m2) of 90Y-DOTA-TATE divided in 3 to 7 doses (most often in 4–5 cycles) repeated every 4 to 9 weeks. For nephroprotection amino-acids formula, before and after each cycle of PRRT was administred.

Results: After the PRRT partial remission was observed in 45%, stabilization in 24% and disease progression in 31% of patients. Seven patients died before completing PRRT. No worsening in renal function was observed after PRRT. In 5 cases after 18 months the creatinin level increased. A drop in WBC was observed mostly after 3–4 cycle of PRRT, with transient grade 3 toxicity in 4 patients. Mean PLT count was within normal limit during the therapy. In 3 patients the value of Hb was assessed as toxicity grade 3. One patient, previously with chemotherapy developed myelodysplastic syndrome. In 76% patients chromogranin A level decreased after therapy.

Conclusions: (1) Therapy with 90Y-DOTA-TATE results in partial remission or stabilization of the disease in most patients. (2) Treatment with labelled somatostatin analogue usually does not induce clinically important haematological or renal toxicity.