Background: Oncolytic virotherapy is a novel immunomodulatory therapeutic approach for relapsed refractory hematologic malignancies. The Indiana strain of Vesicular Stomatitis Virus (VSV) has been engineered to encode interferon beta (IFNβ) and sodium iodine symporter (NIS) to produce VSV-IFNβ-NIS. The virally encoded IFNβ serves as an index of viral proliferation and enhances host anti-tumor immunity. The NIS is inserted as a reporter gene into the viral genome to enable noninvasive monitoring of viral spread using PET/CT imaging. Here we present results of Arm A (patients with low tumor burden) of the Phase I clinical trial (NCT03017820) of intravenous administration of VSV-IFNβ-NIS for patients (pts) with relapsed refractory hematological malignancies: MM, AML, and TCL. Methods: This was a classical 3+3 phase I trial, starting at 5x10^9 TCID50 (50% tissue culture infectious dose) level 1 through 1.7x10^11 TCID50 dose level 4 given as a single IV dose. The primary objective was determining the maximum tolerated dose of VSV-IFNβ-NIS alone; secondary objectives include estimating the safety profile and preliminary efficacy. Correlative objectives include monitoring the pharmacodynamics of viral replication through SPECT/CT imaging with NIS gene, viremia, virus shedding and changes in the immune profile of peripheral blood leukocytes. Adverse events (AEs) are reported based on CTCAE v4; cytokine release syndrome (CRS) grading was based on Lee (Blood 2014; 124(2):188-195) criteria. Results: From April 2017, 12 pts have received IV VSV-IFNβ-NIS in Arm A: MM (7), TCL(4) and AML(1); 3 pts were treated at each dose level (DL) 1 to 4. At DL1, there were five grade 3 hematologic AEs (leukopenia [1], neutropenia [1], lymphopenia [3]) and no grade 3+ non-hematologic AEs. At DL2, three grade 3 hematologic AEs (anemia [2], lymphopenia [1]), four grade 4 hematologic AEs (neutropenia [1], leukopenia [1], lymphopenia [1] and thrombocytopenia [1]). There was 1 event of grade 2 CRS at DL2, two grade 3 non-hematologic AEs (nausea [1], dehydration [1]). At DL3, there was one grade 4 hematologic AE (neutropenia [1]), three grade 3 hematologic AEs (lymphopenia [2], leukopenia [1]), and one grade 3 non-hematologic AE (vasovagal reaction [1]). One grade 2 and grade 1 CRS by Lee criteria were observed. At DL4, there were three grade 3 hematologic AEs (lymphopenia [1], neutropenia [1], thrombocytopenia [1]), and three grade 3 non-hematologic AEs (AST increase [1], skin infection [1], soft tissue infection [1])and two grade 2 CRS. There were no dose limiting toxicities. There was one partial response (DL2) and one complete response (DL4); 3 pts had stable disease, 7 pts progressed. The MM pts receiving VSV-IFNβ-NIS at DL4 had stable disease. Six of the 7 MM pts demonstrated transient reduction in serum level of involved free light chain (LC) after VSV-IFNβ-NIS infusion, with median 20.4% reduction of the involved LC within 48 hrs. Viremia was detectable in all pts at the end of infusion, to varying levels at 30 mins, 1, 2, 4, 24, 48h or 72 hrs post infusion. No persistent viremia was observed. No infectious virus was recovered in buccal swabs or urine and neutralizing anti-VSV antibodies were present by day 29. The IFN levels were detectable within 30 minutes of infusion and peaked between 4 and 48 hrs. The pts with a diagnosis of TCL mounted higher hIFNβ levels within 48 hrs. Remarkably, the TCL pt with CR (DL4) mounted a peak hIFNβ response of 18213.3pg/ml at 48 hrs post infusion, approximately 15-fold higher than any other pt enrolled in the study; and highest neutralizing antibody titer (1:40960). Conclusion: VSV-IFNβ-NIS can be safely administered by intravenous infusion in pts with hematological malignancies, up to a dose level of 1.7 x 1011 TCID50, without dose limiting toxicities and no CRS higher than grade 2. In this small phase 1 study, pts with T-cell lymphoma demonstrated the strongest signal of response, with one confirmed partial response at DL2 and one complete response at DL4. IFNβ is an early biomarker of tumor susceptibility; the magnitude of IFNβ elevation appears to correlate with treatment response. There were no confirmed responses in pts with MM, but the 20.4% transient reduction in LC suggests that combination strategies with VSV-IFNβ-NIS may result in deeper and sustained responses in MM. Future trials investigating combination strategies with immune modulatory drugs are being planned. Disclosures Peng: Imanis: Other: Equity Ownership. Witzig:Karyopharm Therapeutics: Research Funding; Immune Design: Research Funding; Spectrum: Consultancy; Incyte: Consultancy; Acerta: Research Funding; MorphSys: Consultancy; AbbVie: Consultancy; Celgene: Consultancy, Research Funding. Dispenzieri:Intellia: Research Funding; Pfizer: Research Funding; Takeda: Research Funding; Alnylam: Research Funding; Janssen: Research Funding; Celgene: Research Funding. Gertz:Celgene: Consultancy; Annexon: Consultancy; Sanofi: Consultancy; Appellis: Consultancy; Amgen: Consultancy; Medscape: Consultancy, Speakers Bureau; Physicians Education Resource: Consultancy; Data Safety Monitoring board from Abbvie: Membership on an entity's Board of Directors or advisory committees; NCI SPORE MM: Research Funding; Johnson and Johnson: Speakers Bureau; Springer Publishing: Patents & Royalties; Amyloidosis Foundation: Research Funding; Advisory Board for Proclara: Membership on an entity's Board of Directors or advisory committees; Alnylam: Consultancy; Ionis/Akcea: Consultancy; Spectrum: Consultancy, Research Funding; Prothena: Consultancy; DAVA oncology: Speakers Bureau; i3Health: Consultancy; Advisory Board for Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; International Waldenstrom Foundation: Research Funding. Dingli:Rigel: Consultancy; Bristol Myers Squibb: Research Funding; Janssen: Consultancy; Alexion: Consultancy; Apellis: Consultancy; Karyopharm Therapeutics: Research Funding; Millenium: Consultancy; Sanofi-Genzyme: Consultancy. Kapoor:Cellectar: Consultancy; Celgene: Honoraria; Janssen: Research Funding; Sanofi: Consultancy, Research Funding; Amgen: Research Funding; Takeda: Honoraria, Research Funding; GlaxoSmithKline: Research Funding. Lin:Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Legend BioTech: Consultancy; Juno: Consultancy; Bluebird Bio: Consultancy, Research Funding; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Merck: Research Funding; Takeda: Research Funding; Gamida Cells: Consultancy; Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Vineti: Consultancy. Kumar:Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Cellectar: Other; Carsgen: Other, Research Funding; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Merck: Consultancy, Research Funding; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Sanofi: Research Funding; Dr. Reddy's Laboratories: Honoraria; Adaptive Biotechnologies: Consultancy; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Kite Pharma: Consultancy, Research Funding; Novartis: Research Funding; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; MedImmune: Research Funding; Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Karyopharm: Consultancy; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; BMS: Consultancy, Research Funding; Genecentrix: Consultancy; Tenebio: Other, Research Funding. Russell:Imanis: Other: Equity Ownership. OffLabel Disclosure: This describes of administration of Vesicular Stomatitis Virus Genetically Engineered to Express NIS and human interferon, in Patients with Relapsed or Refractory Hematologic malignacies

The purpose of this study was to evaluate 18F-FDG PET/CT for the diagnosis, management, and treatment of Erdheim–Chester disease (ECD). Methods: Our institutional database (2007–2017) was retrospectively reviewed for patients with pathologically proven ECD. A chart review yielded demographics, clinical information, and 5 categories of clinical impact. Two radiologists in consensus interpreted the images. Imaging findings were correlated with clinical data. Results: Seventy-one 18F-FDG PET/CT examinations were performed for 32 patients. The average SUVmax of the most active disease site was 9.2 (SD, 6.1). The most common sites involved were the skeleton (90.6% of patients, including 47% with axial and pelvic skeletal involvement), kidneys (81.3%), and central nervous system (CNS) (46.9%). Twenty-six patients were tested for a proto-oncogene B-Raf V600E (BRAF) mutation (18 had the mutation and 8 did not). The presence of a BRAF mutation was associated with 18F-FDG–avid CNS disease (P = 0.0357), higher SUVmax (P = 0.0044), and greater mortality (P = 0.0215). The presence of CNS disease had 88% specificity and a 92% positive predictive value for predicting the presence of a BRAF mutation. PET/CT examination results influenced patient management in 48% of cases (34/71). Conclusion: 18F-FDG PET/CT results may act as a biomarker for the presence of a BRAF mutation, aid in establishing a diagnosis, guide biopsies, and gauge the treatment response in ECD patients. Axial and pelvic skeletal involvement is greater than previously reported.

Choline positron emission tomography (PET)/computed tomography (CT), with both carbon 11 (C-11) choline and fluorine 18 (F-18) choline, is an increasingly used tool in the evaluation of patients with biochemically recurrent prostate cancer. It has allowed detection and localization of locally recurrent and metastatic lesions that were difficult or impossible to identify using more conventional modalities. Many of the patients followed for their prostate cancer are elderly and have a higher rate of nonprostate cancer lesions or malignancies. As our experience with choline PET/CT has grown, it has become apparent that many of these nonprostate cancer processes, both benign and malignant, can be detected. Invasive thymoma, renal cell carcinoma, papillary thyroid carcinoma, and parathyroid adenoma are a few of the processes that have been incidentally detected with C-11-choline PET/CT at our institution and have significantly altered subsequent clinical management of the patient. Although most of the secondary lesions are detected due to their increased C-11-choline avidity, several have been detected due to their decreased or lack of avidity in the background of a highly avid organ. For instance, large liver masses that are relatively non-choline-avid create large activity defects in the otherwise highly active liver. Familiarity with normal C-11-choline physiologic activity, the most common prostate metastatic patterns, and imaging characteristics of secondary lesions is essential for the detection and correct diagnosis of such lesions so that proper follow-up and management can be recommended. (C) RSNA, 2016.

Choline positron emission tomography (PET)/computed tomography (CT), with both carbon 11 ((11)C) choline and fluorine 18 ((18)F) choline, is an increasingly used tool in the evaluation of patients with biochemically recurrent prostate cancer. It has allowed detection and localization of locally recurrent and metastatic lesions that were difficult or impossible to identify using more conventional modalities. Many of the patients followed for their prostate cancer are elderly and have a higher rate of nonprostate cancer lesions or malignancies. As our experience with choline PET/CT has grown, it has become apparent that many of these nonprostate cancer processes, both benign and malignant, can be detected. Invasive thymoma, renal cell carcinoma, papillary thyroid carcinoma, and parathyroid adenoma are a few of the processes that have been incidentally detected with (11)C-choline PET/CT at our institution and have significantly altered subsequent clinical management of the patient. Although most of the secondary lesions are detected due to their increased (11)C-choline avidity, several have been detected due to their decreased or lack of avidity in the background of a highly avid organ. For instance, large liver masses that are relatively non-choline-avid create large activity defects in the otherwise highly active liver. Familiarity with normal (11)C-choline physiologic activity, the most common prostate metastatic patterns, and imaging characteristics of secondary lesions is essential for the detection and correct diagnosis of such lesions so that proper follow-up and management can be recommended.

PURPOSE:We compared signal change on magnetic resonance imaging (MRI) with fat suppression and bone scan activity of lumbar facet joints to determine if these two imaging findings are correlated.METHODS:We retrospectively identified all patients who underwent imaging of the lumbar spine for pain evaluation using both technetium-99m methylene disphosphonate single-photon emission computed tomography/computed tomography (99mTc-MDP SPECT/CT) and MRI with at least one fat-suppressed T2- or T1-weighted sequence with gadolinium enhancement within a 180-day interval, at our institution between 1 January 2008 and 19 February 2013. Facet joint activity on 99mTc-MDP SPECT/CT and peri-facet signal change on MRI were rated as normal or increased. Agreement between the two examination types were determined with the κ and prevalence-adjusted bias-adjusted κ (PABAK) statistics.RESULTS:This study included 60 patients (28 male, 47%), with a mean age of 49±19.7 years (range, 12-93 years). The κ value indicated no agreement between 99mTc-MDP SPECT/CT and MRI (κ=-0.026; 95% confidence interval: -0.051, 0.000). The PABAK values were fair to high at each spinal level, which suggests that relatively low disease prevalence lowered the κ values. Together, the κ and PABAK values indicate that there is some degree of intermodality agreement, but that it is not consistent.CONCLUSION:Overall, facet joint signal change on fat-suppressed MRI did not always correlate with increased 99mTc-MDP SPECT/CT activity. MRI and 99mTc-MDP SPECT/CT for facet joint evaluation should not be considered interchangeable examinations in clinical practice or research.

The clinical and imaging evaluation of peripheral neuropathies in patients with cancer is challenging. It is critically important to differentiate malignant invasion of the peripheral nervous system from nonmalignant causes, such as radiation-induced neuritis, neuropathy associated with chemotherapy, and inflammatory neuropathies. Contrast material-enhanced magnetic resonance (MR) imaging is the initial noninvasive test of choice; however, interpretation can be challenging when the anatomic features are distorted by prior surgery, radiation, or both. Fluorine 18 ((18)F)-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is an imaging adjunct to MR imaging that is particularly helpful for evaluating peripheral nerves because the metabolic activity depicted with (18)F-FDG PET/CT helps differentiate malignant from benign disease and assists in making certain management decisions. For example, sites of high (18)F-FDG activity in a peripheral nerve can be targeted to increase the diagnostic yield of a biopsy because malignant involvement of peripheral nerves can be patchy. Of note, (18)F-FDG PET/CT can show clinically unsuspected metastases elsewhere in the body. If cancer is found, (18)F-FDG PET/CT allows excellent assessment of treatment response. (18)F-FDG PET/CT is also useful in evaluating primary nerve sheath tumors in that such tumors with low metabolic activity on FDG PET/CT images are unlikely to be malignant, although the specificity is limited. It is essential to have a good understanding of the imaging characteristics of benign and malignant causes of peripheral neuropathy if (18)F-FDG PET/CT is to be used effectively for accurate diagnosis.

UNLABELLED:The aim of this study was to compare (11)C-choline PET/CT with pelvic multiparametric MR imaging for detection of recurrent prostate carcinoma in patients with suspected recurrence after radical prostatectomy and to identify an optimal imaging method to restage these patients. METHODS:This was a retrospective, single-institution study of 115 prostatectomy patients with suspected tumor recurrence who underwent both (11)C-choline PET/CT and multiparametric MR imaging with endorectal coil. The reference standard included histopathology, treatment change, and imaging follow-up for determination of locally recurrent tumor, lymph node (LN) metastases, and skeletal metastases. Two nuclear medicine and 2 genitourinary radiologists independently and in a masked manner reviewed PET/CT and multiparametric MR imaging, respectively. The reviewers assessed for local recurrence in the prostatectomy bed as well as LN and bone metastases, rating their diagnostic confidence with a 5-point scoring system for each location. Receiver-operating-characteristic analysis was used to compare the 2 modalities. RESULTS:The standard of reference (either positive or negative) for the diagnosis of local recurrence and pelvic LN and bone metastases was met in 87, 70, and 95 patients, respectively. Documented local recurrence and pelvic LN and bone metastases was present in 61 of 87 (70.1%), 50 of 70 (71.4%), and 16 of 95 (16.8%) patients, respectively. Patient-based area under the receiver-operating-characteristic curves of multiparametric MR imaging versus PET/CT for the diagnosis of local recurrence and pelvic LN and bone metastases were 0.909 versus 0.761 (P = 0.0079), 0.812 versus 0.952 (P = 0.0064), and 0.927 versus 0.898 (P = 0.69), respectively. Among 61 patients with local recurrence, 32 patients (52.4%) were correctly diagnosed as having local recurrence by both multiparametric MR imaging and PET/CT, 22 (36.1%) were correctly diagnosed by multiparametric MR imaging only, 6 (9.8%) could not be diagnosed by either modality, and 1 (1.6%) was correctly diagnosed by PET/CT only. The patient-based sensitivity, specificity, and accuracy of multiparametric MR imaging for diagnosing local recurrence were 88.5% (54/61), 84.6% (22/26), and 87.4% (76/87) whereas those of PET/CT for detecting body LN or bone metastases were 92.3% (72/78), 100% (18/18), and 93.8% (90/96), respectively. CONCLUSION:Multiparametric MR imaging with endorectal coil is superior for the detection of local recurrence, PET/CT is superior for pelvic LN metastasis, and both were equally excellent for pelvic bone metastasis. (11)C-choline PET/CT and pelvic multiparametric MR imaging are complementary for restaging prostatectomy patients with suspected recurrent disease.

ObjectiveThe use of technetium-99m methylene diphosphonate single-photon emission tomography/computed tomography (99mTc-MDP SPECT/CT) of the spine and sacrum has increased over the past years; however, there is little information about the optimal clinical role and true clinical impact of this modality. MethodsAll 99mTc-MDP SPECT/CT examinations of the spine and sacrum performed at our large multispecialty institution between 1 January 2008 and 12 April 2012 were identified. The indications, findings, clinical context, and impact on patient management were identified through a retrospective chart review. ResultsOf the 212 99mTc-MDP SPECT/CT examinations of the spine and sacrum identified, 191 (90%) were for pain evaluation, 14 (7%) were to assess infection, and seven (3%) were to evaluate a potential malignancy. The most common specific indication was evaluation of facet joint pain in 70/191 (37%) patients, and the most common finding was facet joint activity in 106/212 (50%) patients. Several findings were reported, although facet joint activity was the most frequent. The other findings included costovertebral joint activity, pars interarticularis defects, an osteoid osteoma, a lumbosacral pseudoarticulation, and a postoperative pseudoarthrosis. A resultant change in clinical management was documented in 168/212 (79%) patients. Ninety-two of the 212 (44%) patients had undergone an MRI of the same region for any indication within ±6 months. Conclusion99mTc-MDP SPECT/CT of the spine and sacrum is most frequently used for the diagnosis and management of pain. It helps identify several potential pain generators, is often used in patients who have a near-contemporaneous MRI, and has an impact on the procedural and/or conservative management in most patients. In addition, several areas in need of future research to establish the optimal clinical role of this modality were identified.

Whole-body positron emission tomography/computed tomography (PET/CT) with [(11)C]- and [(18)F]-labeled choline derivates has emerged as a promising molecular imaging modality for the evaluation of prostate cancer. (11)C- and (18)F-choline PET/CT are used successfully for restaging prostate cancer in patients with biochemical recurrence of disease after definitive therapy, especially when the serum prostate-specific antigen level is >1.0 ng/mL. (11)C- and (18)F-choline PET/CT have more limited roles for the initial staging of prostate cancer and for the detection of tiny lymph node metastases due to the low spatial resolution inherent to PET. Overall, these modalities are most useful in patients with a high pre-test suspicion of metastatic disease. The following is a review of the current clinical roles of (11)C- and (18)F-choline PET/CT in the management of prostate cancer.

The use of technetium-99m methylene diphosphonate single-photon emission tomography/computed tomography (99mTc-MDP SPECT/CT) of the spine and sacrum has increased over the past years; however, there is little information about the optimal clinical role and true clinical impact of this modality.All 99mTc-MDP SPECT/CT examinations of the spine and sacrum performed at our large multispecialty institution between 1 January 2008 and 12 April 2012 were identified. The indications, findings, clinical context, and impact on patient management were identified through a retrospective chart review.Of the 212 99mTc-MDP SPECT/CT examinations of the spine and sacrum identified, 191 (90%) were for pain evaluation, 14 (7%) were to assess infection, and seven (3%) were to evaluate a potential malignancy. The most common specific indication was evaluation of facet joint pain in 70/191 (37%) patients, and the most common finding was facet joint activity in 106/212 (50%) patients. Several findings were reported, although facet joint activity was the most frequent. The other findings included costovertebral joint activity, pars interarticularis defects, an osteoid osteoma, a lumbosacral pseudoarticulation, and a postoperative pseudoarthrosis. A resultant change in clinical management was documented in 168/212 (79%) patients. Ninety-two of the 212 (44%) patients had undergone an MRI of the same region for any indication within ±6 months.99mTc-MDP SPECT/CT of the spine and sacrum is most frequently used for the diagnosis and management of pain. It helps identify several potential pain generators, is often used in patients who have a near-contemporaneous MRI, and has an impact on the procedural and/or conservative management in most patients. In addition, several areas in need of future research to establish the optimal clinical role of this modality were identified.

Introduction: In the setting of an extra-adrenal malignancy, it is a recognized clinical challenge to try and distinguish a benign adrenal mass from a metastatic deposit. Current non-invasive diagnostic tools for adrenal gland evaluation include CT, MRI, PET and PET-CT. Diagnostic interpretative error can occur as evaluations rarely have complete cytologic or histologic correlation for concordance purposes. Aims: To establish the performance characteristics of non-contrast CT attenuation values (Hounsfield units-HU) and the optimal PET-CT maximum standard uptake value (SUVmax) for predicting adrenal malignancy when correlated with adrenal gland endoscopic ultrasound fine needle aspiration (EUS FNA) cytology results. Methods: A prospectively maintained EUS database was reviewed to identify consecutive patients who underwent a left adrenal gland FNA. Non-contrast CT attenuation values and SUVmax scores were calculated. EUS FNA cytology results were used as the reference standard for determining the presence of benign versus malignant adrenal gland status. Results: Sixty-two patients (69 ± 11 years) underwent adrenal EUS FNA, 34 (54.8%) of whom had a clinically suspected or established extra-adrenal malignancy. Non-invasive imaging was suggestive of abnormal adrenal morphology or altered PET-CT FDG activity in 45 (72.6%) patients. Elevated attenuation values (≥10 HU) by non-enhanced CT had a sensitivity and specificity of 100% and 34.6%, respectively. The SUVmax for malignant altered morphology was significantly higher than that for benign lesions [(8.5 ± 3.1 vs 3.3 ± 0.7; (p = 0.0001)]. ROC curve analysis indicated that an optimum cutoff SUVmax of ≥4.1 (AUC 0.92) yielded the best power distinction for malignancy with a sensitivity and specificity of 89% and 100%. Conclusion: When evaluating altered adrenal morphology by non-invasive methods, the performance characteristics of elevated CT attenuation values are suboptimal. But by adopting a SUVmax cut-off value of ≥4.1 could potentially improve such characteristics to detect malignancy.

Introduction We examined the clinical impact of commercially available quantitation software using 3-dimensional stereotactic surface projection (3D-SSP) on the diagnostic accuracy of 18F fluorodeoxyglucose positron emission tomography (18F FDG PET) in mild cognitive impairment (MCI) and Alzheimer disease (AD). Methods Enrollees underwent clinical evaluation to determine cognitive status and subsequent 18F FDG PET neuroimaging. Four blinded readers (2 novices and 2 experts) rated the images for degree of abnormality and interpretive confidence without and with 3D-SSP. Diagnostic accuracy was determined with area under the curve (area under the curve) of a receiver operating characteristic (receiver operating characteristic) curve analysis and change in confidence with model-based means (LSMeans). Results Twenty-three normal controls and 31 patients with cognitive impairment (18 MCI and 13 AD) were enrolled (28 female and 26 male; mean age 74 years). During follow-up (mean 3.6 years), all normal participants remained normal, 12 of 18 participants with MCI progressed to dementia, and all participants with baseline dementia progressed. The area under the curve with 3D-SSP (0.88; 95% CI: 0.76–0.95) was significantly higher than without it (0.72; 95% CI: 0.55–0.83). The specificity increased from 26% to 63% for novices and from 56% to 87% for experts with addition of 3D-SSP, whereas the sensitivity was essentially unchanged at 86% and 86% for the beginners and 81% and 79% for the experts. The interpretive confidence increased significantly from 3.3 to 4.0 (maximum value = 5, P = 0.048). Conclusion The use of commercially available 3D-SSP quantitation improved diagnostic accuracy for evaluation of MCI and AD with 18F FDG PET.

OBJECTIVE The objective of this article is to provide an illustrative tutorial showing the utility of (11)C-choline PET/CT for imaging prostate cancer. CONCLUSION Carbon-11-labeled choline PET/CT is a powerful adjunct to the currently available imaging modalities for evaluating prostate cancer. As with any diagnostic method, false-positives and false-negatives occur. However, these diagnostic errors can be reduced if readers are familiar with the normal and abnormal patterns of (11)C-choline distribution in the body.

The aim of this study was to examine the clinical impact of three-dimensional surface projection quantitative analysis on the diagnostic accuracy of FDG PET in mild cognitive impairment (MCI) and Alzheimer disease (AD). Twenty-three controls (age 72.7 ± 9.0; DRS 12.5 ± 2.1) and 31 impaired patients (18 MCI and 13 AD; age 74.0 ± 7.1; DRS 6.4 ± 3.0) underwent FDG PET. Transaxial FDG PET images were rated by 4 readers separately, 2 beginners and 2 experts each in 2 sessions. In the first interpretation only black and white and color transaxial images were available. In the second, quantitative images were added and interpretation was performed one month later with the scans randomly shuffled. The readers rated scans on a 5 point scale, 1 being normal and 5 being severely abnormal. All readers were blinded to clinical information. Clinical diagnosis at the time of the scan was used as the gold standard. At a mean followup of 3.4 years, all 23 normal individuals remained cognitively normal, 13 of 13 AD patients progressed clinically and 12 of 18 MCI patients developed AD. The quantitative algorithm enhanced the discrimination of normal to cognitive impaired at baseline (ROC AUC 0.89 vs. 0.72) when the mean rating for all raters was used as the discriminator. The majority this improvement came from significant gains in specificity. The beginners' specificity rose from 28% to 63% and experts from 57% to 87%. Furthermore, the expert readers expressed better agreement between the visual and quantitative methods (pooled Kappa = 0.63; 95% CI: 0.50 to 0.77) in determining normal vs. cognitive impairment relative to the novice raters (pooled Kappa = 0.01; 95% CI: -0.15 to 0.18). In addition, the difference in the mean quantitative and visual scores was also examined with respect to clinical progression. Overall, there was a difference in these two ratings by progression status (p = 0.04). The quantitative scores provided lower scores when associated with less or no cognitive impairment. The use of quantitative software improved the diagnostic accuracy of FDG PET interpretation in patients with MCI or AD. While experienced readers perform better in FDG PET interpretation, both beginners and expert readers were aided by quantitation, notably improving specificity.

2017 Objectives To evaluate the usefulness of 11C-Choline PET/CT for detecting nodal and distant metastases in patients with prostate cancer. Methods A clinical database was used to identify 131 male patients (age: 65.2± 8.45, range 44 to 85)who had been imaged with 11C-Choline PET/CT. Clinical and imaging data were retrospectively reviewed. Patients were injected with an average dose of 618.23 MBq(16.71 mCi) 11C-choline with a range of 312.7 MBq to 833.98 MBq. The patients were scanned within 5 minutes from injection on an integrated PET/CT system. The PET/CT scans were evaluated for the presence of nodal and extranodal uptake. A physician reviewed the medical record to determine whether or not there was knowledge of metastases prior to the original interpretation the 11C-choline scans. Prostate specific antigen levels prior and/or at time of scan were also reviewed for correlation. Results 138 11C-Choline scans were reviewed for 131 subjects. The mean PSA prior to scanning was 12.1 ± 62.2 ng/ml with a range of 0-713 ng/ml. In 61 of 138 scans, abnormal 11C-Choline uptake was found suggesting metastatic disease. Of these 61 subjects, 53 (86.8%) were unknown for metastatic disease and 8 (13.1%) were known prior to PET scan. Forty-seven subjects had positive nodal uptake typical for metastases. Of these 44 (93.6%) were unknown and 3 (6.4%) were known. Twelve (25.5%) subjects with nodal disease had bone abnormalities as well. While the majority of the nodal metastases were confined to the pelvic area, 7(14.8%) subjects had nodal uptake above the diaphragm. Bone abnormalities were seen in 25 subjects of which 20(80%) were unknown and 5(20%) were known prior to PET imaging. Sixteen(64%)of these subjects had abnormalities in the spine. Thirteen(52%) scans showed bone disease but had negative nodes. Other significant findings included 3 subjects with metastatic prostate cancer to sacral nerves. Conclusions 11 C-Choline PET is a useful technique for demonstrating the presence and extent of nodal and distant abnormalities with prostate cancer

Physiologic uptake of 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) by bowel can confound positron emission tomography/computed tomography (PET/CT) assessment for abdominal pathology, particularly within the bowel itself. We wished to determine if oral administration of the antimotility agent, Lomotil (5 mg diphenoxylate hydrochloride/0.05 mg atropine sulfate; G.D. Searle and Company, a division of Pfizer), prior to PET/CT scanning would reduce physiologic uptake of FDG by the small bowel and colon (lower gastrointestinal [GI] tract).