Safety and efficacy of peptide receptor radionuclide therapy in neuroendocrine tumors: A single center experience.

Peptide receptor radionucleotide therapy (PRRT) with 177Lu-dotatate is widely used for the treatment of patients with neuroendocrine tumors (NETs). We analyzed data from 104 patients with NETs treated with 177Lu -dotatate at a US academic center between December 2017 and October 2020 to better understand patterns of long-term efficacy, safety, and toxicity in the real-world setting. 177Lu-dotatate (200 mCi) was administered every eight weeks for four doses. The most common sites of primary disease were small intestine NETs (n = 49, 47%), pancreatic NETs (n = 32, 31%), and lung NETs (n = 7, 7%). Twenty-seven percent had Ki-67 <3%, 49% had Ki-67 between 3-20%, and 13.5% had Ki-67 >20%. The cohort had been pretreated with a median of two prior lines of treatment. Forty percent had received prior liver-directed treatment. Seventy-four percent of patients completed all four doses of treatment. The objective response rate was 18%. The median time-to-treatment failure/death was significantly longer for small-bowel NETs when compared to pancreatic NETs (37.3 months vs. 13.2 months, p = 0.001). In a multivariate model, Ki-67, primary site, and liver tumor burden ≥50% were found to independently predict time-to-treatment failure/death. Around 40% of patients experienced adverse events of ≥grade 3 severity. Treatment-related adverse events leading to discontinuation of therapy happened in 10% of patients. Preexisting mesenteric/peritoneal disease was present in 33 patients; seven of these patients developed bowel-related toxicities including two grade 5 events. We also report two cases of delayed-onset minimal change nephrotic syndrome, which occurred 14 and 27 months after the last dose of PRRT. Lastly, we describe six patients who developed rapid tumor progression in the liver leading to terminal liver failure within 7.3 months from the start of PRRT, and identify potential risk factors associated with this occurrence, which will need further study.

Monitoring and Surveillance of Patients with Gastroenteropancreatic Neuroendocrine Tumors Undergoing Radioligand Therapy.

Radioligand therapy (RLT) with [177Lu]Lu-DOTA-TATE is a standard of care for adult patients with somatostatin-receptor (SSTR)-positive gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Taking advantage of this precision nuclear medicine approach requires diligent monitoring and surveillance, from the use of diagnostic SSTR-targeted radioligand imaging for the selection of patients through treatment and assessments of response. Published evidence-based guidelines assist the multidisciplinary healthcare team by providing acceptable approaches to care; however, the sheer heterogeneity of GEP-NETs can make these frameworks difficult to apply in individual clinical circumstances. There are also contradictions in the literature regarding the utility of novel approaches in monitoring and surveilling patients with GEP-NETs receiving RLT. This article discusses the emerging evidence on imaging, clinical biochemistry, and tumor assessment criteria in the management of patients receiving RLT for GEP-NETs; additionally, it documents our own best practices. This allows us to offer practical guidance on how to effectively implement monitoring and surveillance measures to aid patient-tailored clinical decision-making.

The use of intravenous tPA for the treatment of severe frostbite.

OBJECTIVE: tPA and anticoagulation for treatment of severe frostbite have been reported suggesting differences in imaging techniques, route of tPA administration and management of patients after tPA infusion. This is a report of our results following a protocol of Tc-99m scanning, intravenous tPA administration, followed by either systemic anticoagulation or antiplatelet therapy. METHODS: Patients admitted to our burn center between February 13, 2015 and February 13, 2016 for frostbite who met inclusion criteria were treated with Tc-99m scan and intravenous tPA followed by systemic anticoagulation or antiplatelet therapy. Inclusion criteria included rewarming had not started more than 24h prior to the scan and no contraindications to the use of tPA. RESULTS: Fifteen patients met inclusion criteria and 12 were treated according to the protocol. Nine received scans with 2 showing normal perfusion. Seven displayed perfusion defects and received intravenous tPA. Five recovered fully after tPA. Two who showed improved but abnormal scans after tPA experienced bleeding complications necessitating stopping heparin/Coumadin. Those two went on to partial amputation of digits. CONCLUSION: The use of intra-arterial or intravenous tPA along with angiography or Tc-99m scanning followed by systemic anticoagulation or antiplatelet therapy may be beneficial to patients suffering frostbite.

(18)FDG PET/CT appearance in primary cutaneous diffuse large B-cell lymphoma, leg type.

We report the case of a 70-year-old woman who presented with a small and painless red skin nodule in the right lower leg, which rapidly and significantly increased in size over few weeks and developed a central eschar. Skin biopsy was consistent with primary cutaneous diffuse large B-cell lymphoma, leg type (PCDBCL-LT), an aggressive and rare cutaneous lymphoma. F-FDG PET/CT showed a hypermetabolic soft tissue mass in the right leg with no evidence of systemic involvement of disease.

Pretreatment FDG-PET standardized uptake value as a prognostic factor for outcome in head and neck cancer.

BACKGROUND: We studied the potential prognostic significance of pretreatment 18-fluorodeoxyglucose-positron emission tomography (FDG-PET) standardized uptake value (SUV) in squamous cell carcinoma of the head and neck (SCCHN). METHODS: A retrospective review of the pretreatment FDG-PET scans of 60 patients with SCCHN was performed. All patients received radiotherapy and 37 also received concurrent chemotherapy. SUV was calculated by 2 nuclear-medicine physicians who were blinded to the clinical data. Disease-free survival (DFS) was analyzed with respect to SUV (and other potential prognostic factors). RESULTS: The median SUV was 7.2 (range, 1-24.7); 34 patients (57%) had SUV < 9.0 compared with 26 patients (43%) with an SUV > or = 9.0. The group with low SUV had significantly better 2-year DFS compared with the high SUV group (72% vs 37%), p = .007. On multivariate analysis, stage and age were also associated with DFS, but SUV remained an independent predictor of DFS (hazard ratio: 1.08; p = .016). CONCLUSION: SUV was significantly associated with outcome after modern definitive therapy of SCCHN.