Neuroendocrine neoplasm (NEN) is a type of heterogeneous tumor that originates from peptidergic neurons and neuroendocrine cells. The presence of over-expressed somatostatin receptors (SSTR) on the surface of NEN tumor cells has led to the administration of radiolabeled somatostatin analogs (SSA) in combination with over-expressed SSTR, which is called peptide receptor radionuclide therapy (PRRT). The 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacceticacid- D-Phe1-Tyr3-Thr8-octreotide (DOTATATE)-based α/β radionuclide therapy is one of the representative therapeutic methods of PRRT. This article reviews the progress of research on α/β radionuclide therapy based on DOTATATE and its related combination therapy, drug toxicity and safety, as well as expectation for modalities with clinical value for NEN treatment.

Digestive system tumors are a group of tumors with high incidence in the world nowadays. The assessment of digestive system tumor metastasis by conventional imaging seems to be unsatisfactory. [68Ga]Ga-FAPI, which has emerged in recent years, seems to be able to evaluate digestive system tumor metastasis. We aimed to summarize the current evidence of [68Ga]Ga-FAPI PET/CT or PET/MR for the assessment of primary tumors, lymph node metastases, and distant metastases in digestive system tumors. Besides, we also aimed to perform a meta-analysis of the sensitivity of [68Ga]Ga-FAPI PET diagnosis to discriminate between digestive system tumors, primary lesions, and non-primary lesions (lymph node metastases and distant metastases). PubMed, MEDLINE and Cochrane Library databases were searched from the beginning of the database build to August 12, 2022. All studies undergoing [68Ga]Ga-FAPI PET for the evaluation of digestive tumors were included in the screening and review. Screening and full text review was performed by 3 investigators and data extraction was performed by 2 investigators. Risk of bias was examined with the QUADAS-2 criteria. Diagnostic test meta-analysis was performed with a random-effects model. A total of 541 studies were retrieved. Finally, 22 studies were selected for the systematic review and 18 studies were included in the meta-analysis. In the 18 publications, a total of 524 patients with digestive system tumors, 459 primary tumor lesions of digestive system tumors, and 1921 metastatic lesions of digestive system tumors were included in the meta-analysis. Based on patients, the sensitivity of [68Ga]Ga-FAPI PET for the diagnosis of digestive system tumors was 0.98 (95