Excellent response to Ac-225 DOTATATE therapy in a patient with small cell lung cancer

#4593

Introduction: Peptide receptor radionuclide therapy (PRRT) is a validated treatment for patients with NETs overexpressing somatostatin receptors (SSTR). IHC analysis indicates that up to 50% of small cell lung cancer (SCLC) tumours are SSTR2 positive and thus can be targeted by SSR imaging and PRRT. Therapy with α-emitting radionuclides, such as Ac225, may offer several advantages over β-emitters by having higher energy transfer and more effective cancer cell death.

Aim(s): We report a patient diagnosed with SCLC with an excellent metabolic response to Ac225DOTATATE.

Materials and methods: A 65-yr-old male patient suffering from dyspepsia was referred for an endoscopy, which revealed gastric mass. Biopsy revealed lung large cell NEC with Ki-67: 90%. FDG PET/CT and ceCT showed mediastinal and hilar metastatic lymph nodes and a mass at the left lower lobe. Increased FDG uptake in gastric wall, adrenal glands and pelvic bones were also compatible with metastases. The patient received carboplatin+etoposide, which led to a partial response; however, after 2 months, the patient’s disease progressed, and a repeat gastric biopsy was performed, compatible with SCLC metastases. He received irinotecan+cisplatin, but unfortunately, the patient showed further progression with brain metastases. Then patient underwent SSR PET/CT to search for PRRT eligibility, which showed metastatic diseases with a SUVmax of 20.

Conference:

Presenting Author: Tuncel M

Authors: Tuncel M, Türkan C, Eryılmaz Y, Pala A, Kılıçkap S,

Keywords: Ac-225 DOTATATE, Small Cell lung cancer, PET, somatostatin receptor, PRRT,