Sharma, Akash

641 Background: Tumors of neuroendocrine origin are a rare, heterogenous group of neoplasms. Neuroendocrine neoplasms (NENs) are categorized by site of origin, differentiation status, and by grade (Ki-67 expression and/or mitotic rate), with prognostic variability accordingly. These tumors frequently metastasize to bone, with reported incidence between 6-12% by older SSTR imaging. Our study evaluates patients with well-differentiated tumors of neuroendocrine origin to determine the incidence of osseous metastases when evaluated with higher-sensitivity Ga68 DOTATATE PET scans. The study characterizes the clinical features. Methods: This study was performed at a single, 3-site, US tertiary-care institution. IRB approval was obtained. An automated data extraction tool was used to mine the electronic medical record by searching all positron emission tomography (PET) studies for keywords. Identified scans had to include a combination of the following keywords: “Dotatate” AND “met*” or “lesion” AND “bone” or “osse*” or “skel*”. The individual medical records from the generated report were reviewed to include only patients with 1) well-differentiated NETs of GI and pancreatic origin, lung carcinoid, paraganglioma/pheochromocytoma, or other/unknown primary site, and 2) patients with confirmed osseous metastatic disease. Patient data was entered into a database and evaluated in aggregate. Results: 1,948 PET scans of 1,473 patients were extracted from the EMR, from which 424 patients were identified for inclusion; scans were performed between 5/2018 and 5/2021. Calculated incidence of bone metastasis by Ga68 DOTATATE PET was 28.8%. Median age of included population was 61 years (range 14-92), 49.5% being male. Site of origin was 47.2% bowel NET, 18.9% pancreatic NET, 10.8% lung carcinoid, 10.6% paraganglioma/pheochromocytoma, 2.1% other site, and 10.4% unknown primary. Majority of patients were asymptomatic (64.0%), had sclerotic appearance (76.7%), Krenning 4 (71.4%), and >3 sites (68.3%) of osseous disease. 94.6% of the population had disease of the axial skeleton; 65.6% appendicular. Only 57 patients (13.4%) with osseous disease suffered a fracture, despite metastases at high-risk sites. Fracture occurred at disproportionately low rates in NETs originating in bowel (22.8% of fractures), with proportionately higher rates among pancreatic NETS and paragangliomas/pheochromocytomas (31.6% and 22.8%, respectively). Fractures occurred at proportionately higher rates in higher-grade disease compared to low-grade. Conclusions: Osseous metastatic disease in well-differentiated NENs is evident at much higher rates when imaging with Ga68 DOTATATE PET compared with previously reported data. Nevertheless, fracture occurred at a low rate, suggesting that these patients are at a relatively low risk for skeletal-related events.

Abstract Introduction Pericardial effusion (PE) in patients with infective endocarditis (IE) has been shown to be an independent risk factor for severe complications, however no significant association with mortality has been established. Our study aims to study the significance of pericardial effusion in patients with IE. Methods We performed a retrospective analysis using the United States National Inpatient Sample (NIS) database to identify all the hospital admissions with IE using ICD 10 codes and divided them into two groups based on the presence of PE. The outcomes of interest were in-hospital mortality, in-hospital complications, need for cardiac surgery, and length of stay (LOS). Results A total of 381,300 patients were hospitalized from 2016 to 2019 with IE, of whom 10,370 developed PE. Mean age of patients in the PE group was 51 years and in non-PE group was 61 years with males and Caucasian race being predominant in both groups. PE group had higher rates of in-hospital death (12.7% vs 9%, P≤0.001) and longer in-hospital stay (12 days vs 7 days, P≤0.001) compared to non-PE group. The rates of cardiac surgery were higher in PE group (26.1% vs 8.4%, P≤0.001). The rates of heart failure, heart block, renal failure, cardiogenic shock, and embolic stroke were higher in PE group [Table 1]. Conclusion Our study shows that presence of PE in patients with IE is a predictor for in-hospital mortality, length of stay, and need for cardiac surgery. Also, these patients are at higher risk for heart failure, heart block, cardiogenic shock and embolic stroke. Funding Acknowledgement Type of funding sources: None.

Abstract Late recurrence of prostate cancer after remission with prior radical prostatectomy is uncommon. This is a unique case of biochemical recurrence after being in remission for 12 years. The patient presented with swelling of the right lower extremity with pelvic MRI demonstrating an arterially enhancing filling defect in the right common iliac. An 18F-fluciclovine PET/CT showed corresponding increased intravascular radiotracer activity. Targeted biopsy of the intravascular lesion showed poorly differentiated carcinoma, suggestive of prostate origin. Although MRI evaluation is the mainstay for pelvic evaluation, characterization with 18F-fluciclovine PET/CT imaging adds high whole-body specificity and diagnostic accuracy.