4109 Background: Questions remain regarding when to sequence PRRT and how to categorize pts being considered for the treatment (tx). We previously developed a CS (comprised of 5 categories: available non-PRRT tx for tumor type, prior systemic tx, pt symptoms, tumor burden in critical organs and peritoneal carcinomatosis presence) at Vanderbilt Ingram Cancer Center (VICC) for pts being considered for PRRT to help answer these questions and demonstrated the score to be associated with progression-free survival (PFS) in pts receiving PRRT. Herein, we present the performance of the CS in a validation cohort (VC) and combined cohort (CC). Methods: Our original cohort (OC) included pts with progressive WD NETs (N = 122) under consideration for PRRT between 3/1/2016-3/17/2020 at VICC while our VC included pts under consideration for PRRT (N = 126) between 1/25/2017-11/18/2019 at Ochsner Medical Center (OMC) (N = 51), Markey Cancer Center (MCC) (N = 51) and Rush Medical Center (RMC) (N = 24). All pts in the OC were prospectively scored while pts in the VC were scored retrospectively, with the CS-assigning investigator blinded to patient outcomes. The primary outcome PFS, was estimated by the Kaplan‐Meier method; a Cox proportional‐hazards model adjusting for primary tumor site, tumor grade and number of PRRT doses administered (0, 1-2 or 3-4) was used to analyze effect of CS. Overall survival (OS) was a key secondary outcome. Results: In our VC, on multivariable (MV) analysis, for each 2-point increase in CS, the hazard ratio (HR) for PFS was 2.58 (95% confidence interval (CI) 1.62-4.11). On MV analysis, for each 2-point increase in CS, the HR for OS was 3.89 (95% CI 1.8-4.83). We combined the OC and VC for this analysis in order to increase the predictive power of our originally developed Cox proportional-hazards models. In our CC, of the 248 total pts, median pt age, CS and number of prior tx were 63.3 years, 4 (range 0-8) and 1 (range 0-7), respectively. The most represented primary tumor sites were small intestinal (N = 136), pancreatic (N = 58), unknown primary (N = 26) and lung (N = 14). A total of 140, 82 and 26 pts received 3-4, 0 or 1-2 doses of PRRT, respectively. On MV analysis, for each 2-point increase in CS, the HR for PFS was 2.52 (95% CI 1.90-3.35). On MV analysis, for each 2-point increase in CS, the HR for OS was 3.48 (95% CI 2.33-5.18). No interaction between PRRT doses administered and CS was observed. Conclusions: Increases in CS were strongly associated with worsening PFS and OS in our VC and CC, validating findings from our OC. Although we cannot determine whether the CS specifically predicts PRRT response or is prognostic based upon these data, it is the first presented clinical metric which can categorize pts with WD NETs under consideration for PRRT and estimate anticipated benefit from PRRT for pts.

Importance:Despite the benefit of peptide receptor radionuclide therapy (PRRT) for patients with well-differentiated neuroendocrine tumors (WD NETs), no clinical metric to anticipate benefit from the therapy for individual patients has been previously defined.Objective:To assess whether the prognostic ability of the clinical score (CS) could be validated in an external cohort of patients with WD NETs.Design, Setting, and Participants:This multicenter cohort study's analysis included patients with WD NETs who were under consideration for peptide receptor radionuclide therapy (PRRT) with lutetium-177 (177Lu)-dotatate between March 1, 2016, and March 17, 2020. The original cohort included patients from Vanderbilt-Ingram Cancer Center. The validation cohort included patients from Ochsner Medical Center, Markey Cancer Center, and Rush Medical Center. Patients with paragangliomas, pheochromocytomas and neuroblastomas were excluded. Statistical analysis was performed from June to November 2021.Exposures:PRRT with 177Lu-dotatate or alternate therapies such as everolimus, sunitinib, or capecitabine plus temozolomide.Main Outcomes and Measures:The primary outcome was progression-free survival (PFS) and was estimated by the Kaplan-Meier method; a Cox proportional-hazards model adjusting for primary tumor site, tumor grade, and number of PRRT doses administered was used to analyze association between CS and outcomes.Results:A total of 126 patients (median age [IQR] age: 63.6 [52.9-70.7] years; 64 male individuals) were included in the validation cohort, and the combined cohort (validation and original cohorts combined) had a total of 248 patients (median [IQR] patient age: 63.3 [53.3-70.3] years; 126 male individuals). In the validation cohort, on multivariable analysis, for each 2-point increase in CS, PFS decreased significantly (hazard ratio, 2.61; 95% CI, 1.64-4.16). After finding an association of the CS with PFS in the validation cohort, the original and validation cohorts were combined into the cohort for this analysis. On multivariable analysis, for each 2-point increase in CS, PFS decreased significantly (hazard ratio, 2.52; 95% CI, 1.89-3.36).Conclusions and Relevance:Increases in CS were associated with worsening PFS in the validation cohort, validating findings from the original cohort. These findings suggest that the CS, to our knowledge, represents the first clinical metric to estimate anticipated benefit from PRRT for patients with WD NETs and may be a clinical tool for patients being considered for PRRT.

We developed a clinical score (CS) at Vanderbilt Ingram Cancer Center (VICC) that we hoped would predict outcomes for patients with progressive well-differentiated neuroendocrine tumors (NETs) receiving therapy with Lutetium-177 (177Lu)-DOTATATE. Patients under consideration for 177Lu-DOTATATE between March 1, 2016 and March 17, 2020 at VICC were assigned a CS prospectively. The CS included 5 categories: available treatments for tumor type outside of 177Lu-DOTATATE, prior systemic treatments, patient symptoms, tumor burden in critical organs and presence of peritoneal carcinomatosis. The primary outcome of the analysis was progression-free survival (PFS). To evaluate the effect of the CS on PFS, a multivariable Cox regression analysis was performed adjusting for tumor grade, primary tumor location, and the interaction between 177Lu-DOTATATE doses received (zero, 1-2, 3-4) and CS. A total of 91 patients and 31 patients received 3-4 doses and zero doses of 177Lu-DOTATATE, respectively. On multivariable analysis, in patients treated with 3-4 doses of 177Lu-DOTATATE, for each 1-point increase in CS, the estimated hazard ratio (HR) for PFS was 2.0 (95% CI 1.61-2.48). On multivariable analysis, in patients who received zero doses of 177Lu-DOTATATE, for each 1-point increase in CS, the estimated HR for PFS was 1.22 (95% CI 0.91-1.65). Among patients treated with 3-4 doses of 177Lu-DOTATATE, those with lower CS experienced improved PFS with the treatment compared to patients with higher CS. This PFS difference, based upon CS, was not observed in patients who did not receive 177Lu-DOTATATE, suggesting the predictive utility of the score.

Purpose To measure the SUVs in the tail of the pancreas compared with normal liver parenchyma and somatostatin receptor–positive lesions. Materials and Methods 68Ga-DOTATATE PET/low mAs CT of 35 patients were reviewed. Results There was no significant difference (P = 0.59) between the SUVaverage of normal liver and the SUVpeak of normal tail. Five patients had uptake in the tail slightly above that of normal liver that were interpreted equivocally. In one of these patients with 68Ga-DOTATATE uptake in a peripancreatic lymph node, proven neuroendocrine tumor underwent a distal pancreatectomy and pathologic examination revealed islet cell hyperplasia. Conclusions 68Ga-DOTATATE uptake in the tail of the pancreas above that of normal liver indicates a somatostatin receptor–avid lesion. Uptake in the tail of the pancreas equal to the liver can be normal. Patients with uptake equivalent to the liver should undergo further anatomical imaging before procedural intervention.

Colorectal cancer (CRC) is the third most common cause of malignancy in both men and women. The incidence rate has decreased over the last two decades partially due to an increase in screening. The American Cancer Society (ACS) estimates that there are approximately 149,000 new cases of CRC per year and approximately 50,000 patients per year die from this disease in the USA, representing 10% of new cases and 8% of all cancer deaths. Approximately 70–80% of patients are treated with curative intent, mostly by surgery. Chemotherapy alone, or in combination with radiation (for rectal cancer), is given before or after surgery to most patients whose tumor has penetrated the bowel wall or spread to lymph nodes. The overall survival at 1 and 5 years is 82 and 64%, respectively. The 5-year survival is 90% for localized stage, 68%when there is regional spread, and 10%when there are distant metastases.

1278 Objectives: Neuroendocrine tumors (NETs) are uncommon but with increasing incidence and prevalence. 68Ga-DOTATATE is a PET radiopharmaceutical for somatostatin receptor (SSR) detection. After reviewing multiple patients with 68Ga-DOTATATE PET/CT, the authors noticed equivocal interpretations of uptake in the tail of the pancreas. The purpose of our study was to measure the uptake semi-quantitatively using SUVs in the tail of the pancreas compared to normal liver parenchyma and SSR-positive lesions. Methods: We reviewed the 68Ga-DOTATATE PET/low mAs CT images of 35 consecutive patients performed between October 4, 2017 and January 23, 2018. There were 17 male and 18 females ranging in age from 37 to 80 years (mean +/- SD = 57.1 +/- 10.7). SUVs were measured by two observers and the average values between the two observers were compared between normal liver parenchyma and pancreas tail. Normal liver parenchyma SUVaverage with the size of the region of interest (ROI) = 23.48 cm2, the lesion SUVpeak with the size of the ROI = 0.78 cm2, and the tail of the pancreas SUVpeak. An ABR-certified radiologist reviewed the corresponding available diagnostic CTs and MRI of the abdomen to assess the presence of lesions in the tail of the pancreas. Results: The indications for referral to 68Ga-DOTATATE PET/CT were the following: 1. Evidence of a new lesion in the pancreas (n=9), restaging (n=5), NET metastases (n=11), and elevated tumor markers (n=10). Twenty-four patients had resection or biopsy of a lesion diagnostic of NET prior to and nine had tissue acquisition after the 68Ga-DOTATATE PET/CT. The average normal liver parenchyma SUVaverage was 3.9 +/-1.0. The median SUVpeak of the lesions was 17.65 (interquartile range: 5.55, 24.35). In the 31 patients with a tail of the pancreas without anatomical lesions, the average SUVpeak was 3.7 +/- 1.1. There was no significant difference (p=0.59) between the SUVaverage of normal liver parenchyma and the SUVpeak of normal tail of the pancreas. There were five patients with uptake in the tail of the pancreas slightly above that of normal liver parenchyma that were interpreted equivocally as cancer. One of these patients had 68Ga-DOTATATE uptake in a peripancreatic lymph node in addition to the tail of the pancreas. The fine needle aspiration of the lymph node demonstrated neuroendocrine tumor. He underwent a distal pancreatectomy and pathologic examination revealed islet cell hyperplasia. Conclusion: We observed that68Ga-DOTATATE uptake in the tail of the pancreas above that of normal liver parenchyma was consistent with a SSR-avid lesion. 68Ga-DOTATATE uptake in the tail of the pancreas equal to the liver can be normal. Patients with 68Ga-DOTATATE uptake equivalent to the liver parenchyma should undergo further imaging with either contrast-enhanced CT or MRI before procedural intervention to confirm the presence of a pathological lesion. Figure 1: 68GA-DOTATATE PET/CT of a 43 year-old man who presented with carcinoid syndrome: A. CT transmission, B. Fusion PET/CT image, C. 68Ga-DOTATATE PET, D. Maximum intensity projection (MIP). An outside CT without contrast demonstrated a 1 cm retroperitoneal lymph node at the level of the renal vessels. A fine needle aspiration revealed neuroendocrine tumor. The 68Ga-DOTATATE PET images demonstrated uptake in the retroperitoneal lymph node seen on the MIP. A transaxial image demonstrated uptake in the tail of the pancreas at the same level as normal liver parenchyma (arrow).

PURPOSETo measure the SUVs in the tail of the pancreas compared with normal liver parenchyma and somatostatin receptor-positive lesions.MATERIALS AND METHODSGa-DOTATATE PET/low mAs CT of 35 patients were reviewed.RESULTSThere was no significant difference (P = 0.59) between the SUVaverage of normal liver and the SUVpeak of normal tail. Five patients had uptake in the tail slightly above that of normal liver that were interpreted equivocally. In one of these patients with Ga-DOTATATE uptake in a peripancreatic lymph node, proven neuroendocrine tumor underwent a distal pancreatectomy and pathologic examination revealed islet cell hyperplasia.CONCLUSIONSGa-DOTATATE uptake in the tail of the pancreas above that of normal liver indicates a somatostatin receptor-avid lesion. Uptake in the tail of the pancreas equal to the liver can be normal. Patients with uptake equivalent to the liver should undergo further anatomical imaging before procedural intervention.

In the United States, the medical specialties of nuclear medicine and radiology have a unique relationship in that radiologists practice nuclear medicine, but nuclear medicine physicians do not generally practice radiology. Radiologists are able to practice nuclear medicine after completing 4 months of nuclear medicine rotations during their 4-year training program after internship. Nuclear medicine residents train for 3 years after internship, including 6 months of CT. Over the past 2 decades, nuclear medicine has become more complex. During this time, the nuclear medicine training program was extended from 2 to 3 years [ 1 Graham M.M. Metter D.F. Evolution of nuclear medicine training: past, present, and future. J Nucl Med. 2007; 48: 257-268 PubMed Google Scholar ]. During the same time frame, the radiology requirement for nuclear medicine training decreased from 6 to 4 months [ 2 Oates M.E. Guiberteau M.J. Adoption of the 16-month American Board of Radiology pathway to dual board certifications in nuclear radiology and/or nuclear medicine for diagnostic radiology residents. Acad Radiol. 2014; 21: 1348-1356 Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar ]. The training length of 4 months is based on Nuclear Regulatory Commission requirements for authorized users of radiopharmaceuticals, not on any requirements for clinical nuclear medicine competency [ 3 Harolds J.A. Novelline R.A. Guiberteau M.J. Metter D. Oates M.E. Jobs and new initiatives in nuclear medicine education. J Nucl Med. 2011; 52: 17N-23N PubMed Google Scholar ].

A 39-year-old man presented with new onset of sinus congestion, shortness of breath, and diaphoresis. His laboratory tests were notable for hypercalcemia and lactic acidosis. A CT scan of the head demonstrated mild paranasal disease. CT scan of the chest, abdomen, and pelvis demonstrated omental caking with lymphadenopathy and a thickened loop of bowel in the left upper quadrant suggestive of lymphoma. All abdominal lesions seen in the CT were intensely F-FDG avid with diffuse uptake in the bone marrow. There was markedly decreased F-FDG uptake in both the brain and liver. Histopathology was positive for Burkitt lymphoma.

To compare FDG PET/CT and CT for the guidance of percutaneous biopsies with histological confirmation of lesions.

Neuroendocrine tumors (NETs) are uncommon tumors with increasing incidence and prevalence. Current reports suggest that 68Ga-DOTATATE PET/CT imaging improves diagnosis and staging of NETs compared with 111In-DTPA-octreotide and conventional imaging. We performed a systematic review of 68Ga-DOTATATE for safety and efficacy compared with octreotide and conventional imaging to determine whether available evidence supports U.S. Food and Drug Administration approval. Methods: Medline, EMBASE, Web of Science, and Cochrane Reviews electronic databases were searched from January 1999 to September 2015. Results were restricted to human studies comparing diagnostic accuracy of 68Ga-DOTATATE with octreotide or conventional imaging for pulmonary or gastroenteropancreatic NET and for human studies reporting safety/toxicity for 68Ga-DOTATATE with 10 subjects or more thought to have NETs. Direct communication with corresponding authors was attempted to obtain missing information. Abstracts meeting eligibility criteria were collected by a research librarian and assembled for reviewers; 2 reviewers independently determined whether or not to include each abstract. If either reviewer chose inclusion, the abstract was accepted for review. Results: Database and bibliography searches yielded 2,479 articles, of which 42 were eligible. Three studies compared the 2 radiopharmaceuticals in the same patient, finding 68Ga-DOTATATE to be more sensitive than octreotide. Nine studies compared 68Ga-DOTATATE with conventional imaging. 68Ga-DOTATATE estimated sensitivity, 90.9% (95% confidence interval, 81.4%–96.4%), and specificity, 90.6% (95% confidence interval, 77.8%–96.1%), were high. Five studies were retained for safety reporting only. Report of harm possibly related to 68Ga-DOTATATE was rare (6 of 974), and no study reported major toxicity or safety issues. Conclusion: No direct comparison of octreotide and 68Ga-DOTATATE imaging for diagnosis and staging in an unbiased population of NETs has been published. Available information in the peer-reviewed literature regarding diagnostic efficacy and safety supports the use of 68Ga-DOTATATE for imaging of NETs where it is available.

a Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD b Department of Radiology, University of California–San Francisco, San Francisco, CA c Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Canada d Pat and Jim Calhoun Cardiology Center, UConn Health, Farmington, CT e Department of Radiology, Vanderbilt University Medical Center, Nashville, TN f Division of Nuclear Medicine, Brigham and Women’s Hospital, Boston, MA g Division of Nuclear Medicine, Washington University School of Medicine, St. Louis, MO h Turku PET Centre, Turku University Hospital, Turku, Finland i Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA j Department of Radiology, Montefiore Medical Center, Bronx, NY

![Figure][1] Dominique Delbeke This issue of The Journal of Nuclear Medicine concludes my 5-year term as Editor-in-Chief. JNM is one of the educational flagships of the Society of Nuclear Medicine and Molecular Imaging. The JNM mission statement is “[to advance] the knowledge and

Our purpose was to evaluate the safety and efficacy of 68Ga-DOTATATE PET/CT compared with 111In-pentetreotide imaging for diagnosis, staging, and restaging of pulmonary and gastroenteropancreatic neuroendocrine tumors. Methods: 68Ga-DOTATATE PET/CT and 111In-pentetreotide scans were obtained for 78 of 97 consecutively enrolled patients with known or suspected pulmonary or gastroenteropancreatic neuroendocrine tumors. Safety and toxicity were measured by comparing vital signs, serum chemistry values, or acquisition-related medical complications before and after 68Ga-DOTATATE injection. Added value was determined by changes in treatment plan when 68Ga-DOTATATE PET/CT results were added to all prior imaging, including 111In-pentetreotide. Interobserver reproducibility of 68Ga-DOTATATE PET/CT scan interpretation was measured between blinded and nonblinded interpreters. Results: 68Ga-DOTATATE PET/CT and 111In-pentetreotide scans were significantly different in impact on treatment (P < 0.001). 68Ga-DOTATATE PET/CT combined with CT or liver MRI changed care in 28 of 78 (36%) patients. Interobserver agreement between blinded and nonblinded interpreters was high. No participant had a trial-related event requiring treatment. Mild, transient events were tachycardia in 1, alanine transaminase elevation in 1, and hyperglycemia in 2 participants. No clinically significant arrhythmias occurred. 68Ga-DOTATATE PET/CT correctly identified 3 patients for peptide-receptor radiotherapy incorrectly classified by 111In-pentetreotide. Conclusion: 68Ga-DOTATATE PET/CT was equivalent or superior to 111In-pentetreotide imaging in all 78 patients. No adverse events requiring treatment were observed. 68Ga-DOTATATE PET/CT changed treatment in 36% of participants. Given the lack of significant toxicity, lower radiation exposure, and improved accuracy compared with 111In-pentetreotide, 68Ga-DOTATATE imaging should be used instead of 111In-pentetreotide imaging where available.