Kann ein prä-therapeutisches Gallium-68-DOTATOC-PET/CT durch SUV-Messung eine Prognose über das progressionsfreie Überleben und Therapieansprechen von Patienten/-innen mit metastasierten neuroendokrinen Tumoren des Gastrointestinaltrakts nach PRRT mit therapeutischem Lutetium-177 geben?

In this paper 62 patients were investigated who were diagnosed and treated with Ga-68-DOTATOC-PET/CT and consecutive Lu-177-PRRT therapy for metastatic neuroendocrine neoplasms of the digestive system at the University Hospital of Marburg between 2014 and 2019. The analysis focused mainly on potential predictors of progression free survival: Ki67 proliferation index, WHO-Grading, Chromogranin A, localization of the primary, age at diagnosis and sex. To conclude, this paper showed Ki67 proliferation index as a feasible prognostic marker of progression free survival in patients with metastatic neuroendocrine tumors of the digestive system after Lu-177-PRRT treatment. The differenciation between G1 and G2 neoplasms should be revised from Ki67=2% to a threshold of Ki67=5% in order to provide a more reliable prognosis. SUVmax was proven to be an unfeasible prognostic marker for progression free survival in patients who had already been selected for PRRT by SUVmax measurement. Chromogranin A can be used as a tumormarker and representative of disease progression. Age at diagnosis and Chromogranin A were did not present as suitable prognostic values of progression free survival. Pancreatic neoendocrine neoplasms were associated with a poorer prognosis than NET with an ileal or jejunal primary. There was a significant difference in the tracer accumulation in metastases of different primary sites but none with regard to WHO-Grading or status progressive disease. Surprisingly, there was a clear difference in progression free survival of men and women, which could not finally be clarified. Furthermore, women suffered from progressive disease more often than men. Future prospective studies should continue to examine differences with regard to gender in order to offer more insight as to integrate such results.