Abstract
PURPOSE: Rectal neuroendocrine neoplasia (NEN) is more common than other NEN origins, but is less commonly metastatic. However, when present, distant disease carries a particularly poor prognosis. Evidence guiding optimal treatment of such patients is lacking. We assessed PRRT outcomes in patients with somatostatin receptor (SSTR) positive metastatic rectal NEN from two referral centres.
METHODS: Patients treated with PRRT were retrospectively reviewed. Morphologic (RECIST 1.1), SSTR imaging responses and toxicity were assessed 3 months post-PRRT. Kaplan-Meier estimate was used to determine progression-free survival (PFS) and overall survival (OS) from start of PRRT.
RESULTS: Twenty-seven consecutive patients (M = 20, age 31-81 years) were reviewed. The majority (70%) had ENETs grade 2 disease (19 patients), three had Grade 3, one Grade 1, and four not documented. Overall, 63% (10/16 patients with available FDG PET/CT) had FDG avid disease. Twenty-six patients were treated for disease progression. Most had 177Lu-DOTA-octreotate with median cumulative activity of 30 GBq, median four cycles. 14 patients had radiosensitising chemotherapy (5FU or capecitabine). At 3 months post-PRRT, CT disease control rate (DCR) was 96%: partial response was observed in 70% (19/27) and stable disease in 26%. All but one had partial SSTR imaging response. The median PFS was 29 months. Ten patients died, with median overall survival 81 months with a median follow-up of 67 months. Seventeen patients had further treatments after initial PRRT (10 had further cycles of PRRT). Three patients had grade 3 lymphopenia, without significant renal toxicity, MDS or leukaemia.
CONCLUSION: Our results indicate high efficacy and morphologic responses with minimal toxicity and very encouraging survival from PRRT in patients with metastatic rectal NEN despite the adverse prognostic features of this cohort. Further prospective PRRT trials are warranted in this subgroup.
See also:
- Official Web Site: The Di Bella Method;
- Somatostatin in oncology, the overlooked evidences - In vitro, review and in vivo publications;
- Publication, 2018 Jul: Over-Expression of GH/GHR in Breast Cancer and Oncosuppressor Role of Somatostatin as a Physiological Inhibitor (from Di Bella's Foundation);
- Publication, 2019 Aug: The Entrapment of Somatostatin in a Lipid Formulation: Retarded Release and Free Radical Reactivity (from Di Bella's Foundation);
- Publication, 2019 Sep: Effects of Somatostatin and Vitamin C on the Fatty Acid Profile of Breast Cancer Cell Membranes (from Di Bella's Foundation);
- The Di Bella Method (A Fixed Part - Bromocriptine and/or Cabergoline);
- Oesophageal squamocellular carcinoma: a complete and objective response;
- Pancreatic Adenocarcinoma: clinical records on 17 patients treated with Di Bella's Method;
- Neuroblastoma: Complete objective response to biological treatment.