r Players with the most WAR for their current club By mlb.mlb.com Published On :: Sun, 3 Feb 2019 20:35:07 EDT We are looking at the players on each active roster who are making history for their franchises every time they step on the field. We're looking at the player who has compiled the highest WAR (per Baseball Reference) for his current team so far in his career. Full Article
r D-backs add mental skills dept. to aid players By mlb.mlb.com Published On :: Fri, 1 Feb 2019 15:05:06 EDT In an effort to help develop their players on and off the field, the D-backs have added a mental skills department to their baseball operations staff. Full Article
r Inbox: Are D-backs in a rebuild year? By mlb.mlb.com Published On :: Fri, 1 Feb 2019 10:00:00 EDT Hi Steve, wondering if this is a rebuild year? Full Article
r This is the D-backs prospect to watch in camp By mlb.mlb.com Published On :: Mon, 4 Feb 2019 21:10:42 EDT The countdown to pitchers and catchers reporting is down to single digits for all 30 MLB clubs, but as exciting as it is to see the return of Major League stars, it's also a time to dream about the next wave of baseball talent. Full Article
r D-backs pair among best starting pitcher duos By mlb.mlb.com Published On :: Wed, 6 Feb 2019 22:10:30 EDT Most Major League teams still use a five-man starting rotation, but it takes a lot more pitchers than that to make it through a 162-game season. It certainly helps to have a potent one-two punch at the top of the rotation. Full Article
r Get ready to watch: MLB.TV available for 2019 By mlb.mlb.com Published On :: Wed, 6 Feb 2019 10:55:51 EDT Spring Training is imminent, Opening Day is within sight and the big league season isn't complete for fans without a subscription to MLB.TV. The most comprehensive streaming service in professional sports is now available for the 2019 season. Full Article
r Widener among biggest prospect bargains By mlb.mlb.com Published On :: Thu, 7 Feb 2019 21:15:32 EDT Considering the players that get the big bucks often get most of the attention when they are signed and drafted, let's take some time to look at the other end of the spectrum. Here are the biggest steals on the Top 100 Prospects list. Full Article
r 10 players you forgot were once D-backs By mlb.mlb.com Published On :: Thu, 7 Feb 2019 23:15:46 EDT When you think of the D-backs, what players spring to mind? Luis Gonzalez, Randy Johnson, Paul Goldschmidt and Matt Williams are probably some of the names that arise. But what names are familiar to baseball fans but might have even some D-backs fans saying, "He was a Diamondback?" Full Article
r Here's your guide to D-backs Spring Training By mlb.mlb.com Published On :: Wed, 6 Feb 2019 15:24:17 EDT The D-backs will open their 22nd Spring Training on Feb. 13 when pitchers and catchers go through their first workout. Here is all you need to know to be ready for the action. Full Article
r Reloaded D-backs team set for new season By mlb.mlb.com Published On :: Thu, 7 Feb 2019 17:22:40 EDT The D-backs will work to compete in 2019 while continuing to build up the farm system, which has some pitching at the top end with better position players at the lower levels. Full Article
r Inbox: Is D-backs' closer Holland or Bradley? By mlb.mlb.com Published On :: Fri, 8 Feb 2019 17:55:36 EDT With Greg Holland now signed, will he be the closer or is that still going to be Archie Bradley? Beat reporter Steve Gilbert answers this question and more from fans as Spring Training approaches. Full Article
r Lamb's health a big spring storyline for D-backs By mlb.mlb.com Published On :: Sat, 9 Feb 2019 15:45:00 EDT There will be a lot of attention paid to D-backs infielder Jake Lamb when Spring Training gets underway. Lamb, of course, is coming off a season that was almost entirely lost to a left shoulder injury. His healthy return would play a big part in helping the D-backs' offense overcome the departures of Paul Goldschmidt and A.J. Pollock during the offseason. Full Article
r D-backs announce record turnout to Fan Fest By mlb.mlb.com Published On :: Sat, 9 Feb 2019 21:30:28 EDT As he walked around D-backs Fan Fest on Saturday afternoon at Salt River Fields, general manager Mike Hazen was pleasantly surprised to see the fan reaction as a record crowd of over 40,000 poured into the event. Full Article
r Predicting the D-backs' Opening Day roster By mlb.mlb.com Published On :: Mon, 11 Feb 2019 10:59:54 EDT Here's an early look at how the D-backs' 25-man roster could shape up on Opening Day. Full Article
r Uniform patch to mark 150 years of pro baseball By mlb.mlb.com Published On :: Tue, 12 Feb 2019 10:09:05 EDT All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team. Full Article
r D-backs agree to 1-year deal with Joseph By mlb.mlb.com Published On :: Wed, 13 Feb 2019 09:31:40 EDT The Arizona Diamondbacks agreed to terms with catcher Caleb Joseph on a one-year contract. To make room for Joseph on the roster, the D-backs placed right-hander Taijuan Walker on the 60-day injured list. The D-backs' 40-man roster remains at 40. Full Article
r D-backs to sort out closer role in spring By mlb.mlb.com Published On :: Wed, 13 Feb 2019 19:59:44 EDT After watching his pitchers and catchers go through their first workout Wednesday, D-backs manager Torey Lovullo said it was too early to say whether Archie Bradley, Greg Holland or Yoshihisa Hirano would be his closer come Opening Day. Full Article
r D-backs expect leaders to emerge in spring By mlb.mlb.com Published On :: Wed, 13 Feb 2019 10:00:00 EDT As D-backs pitchers and catchers begin their first official workout of the spring on Wednesday morning, one of the biggest questions facing the organization is who will fill the leadership vacuum. Full Article
r Prospects who should vie for a roster spot By mlb.mlb.com Published On :: Thu, 14 Feb 2019 19:36:11 EDT The 30 prospects below all are getting very long looks this spring with an eye toward breaking camp with the parent club. Even if they start the year in the Minors, they all should get the chance to contribute at some point in the very near future. Full Article
r Kelly already knows his way around ST facility By mlb.mlb.com Published On :: Thu, 14 Feb 2019 19:50:20 EDT Yes, catcher Carson Kelly is new to the D-backs this spring, but this wasn't the first time he's gotten to see what the inside of Salt River Fields looks like. Full Article
r Marte confident transition to CF will be smooth By mlb.mlb.com Published On :: Thu, 14 Feb 2019 19:16:45 EDT Ketel Marte does not lack for confidence when it comes to switching from second base/shortstop to center field, which is where he's expected to see a lot of time this season. Full Article
r Greinke arrives at D-backs camp By mlb.mlb.com Published On :: Fri, 15 Feb 2019 19:05:12 EDT D-backs ace Zack Greinke reported to Salt River Fields on Friday after missing the first two days of pitcher and catcher workouts. Full Article
r 'Campfire drill' helps pitchers, catchers bond By mlb.mlb.com Published On :: Fri, 15 Feb 2019 18:39:10 EDT After seeing improved communication between pitchers and catchers last year, the "campfire" drill was put back on the D-backs' schedule and took place Friday at Salt River Fields. Full Article
r Greinke discusses commitment to D-backs By mlb.mlb.com Published On :: Sat, 16 Feb 2019 19:23:55 EDT Despite a stiff neck, which he says came on a recent airplane flight, D-backs ace Zack Greinke said Saturday that he feels much better physically than he did last year when he reported to Spring Training. Here are five takeaways from Greinke's Saturday session with reporters. Full Article
r D-backs' Top 30 prospects list By m.mlb.com Published On :: Fri, 3 Mar 2017 19:57:33 EDT Who do the D-backs have in the pipeline? Get scouting reports, video, stats, projected ETAs and more for Arizona's Top 30 Prospects on MLBPipeline.com's Prospect Watch. Full Article
r Reasons for optimism for each MLB club By mlb.mlb.com Published On :: Sun, 17 Feb 2019 21:02:04 EDT On this opening week of Spring Training, all 30 Major League teams have one thing in common: optimism. Here's an optimism cheat sheet for each of them. Full Article
r Lovullo expects D-backs to vie for playoff spot By mlb.mlb.com Published On :: Sun, 17 Feb 2019 18:28:54 EDT Monday morning, D-backs manager Torey Lovullo will stand in front of his entire team prior to the first full-squad workout of the spring. Full Article
r Future closer? Confidence runs high for Lopez By mlb.mlb.com Published On :: Sun, 17 Feb 2019 19:31:50 EDT It was the eighth inning of a late September game against the Dodgers when D-backs right-hander Yoan Lopez showed that not only might he have the stuff to be a future closer, but also the moxie of one as well. Full Article
r The D-backs' Spring Training battle to watch By mlb.mlb.com Published On :: Mon, 18 Feb 2019 18:20:16 EDT The next five weeks will see lots of shuffling on Major League rosters. Here are the most intriguing positional battles on each of the 30 MLB clubs. Full Article
r Lamb continues to progress at first base By mlb.mlb.com Published On :: Mon, 18 Feb 2019 20:29:25 EDT Jake Lamb's education at first base hit another checkpoint during Monday's initial full-squad workout when he went through bunt drills for the first time. Full Article
r D-backs ready to move on from late 2018 skid By mlb.mlb.com Published On :: Mon, 18 Feb 2019 19:26:11 EDT They've talked in small groups. They've talked in larger groups. The front office has discussed it. It's a topic that kept manager Torey Lovullo up at night at times. What in the world happened to the D-backs last September when they watched the National League West Division lead slip away during an 8-19 finish? Full Article
r Tomas getting work in at first base By mlb.mlb.com Published On :: Tue, 19 Feb 2019 20:31:55 EDT As the D-backs went through fielding drills Tuesday, Yasmany Tomas spent his time at first base rather than in the outfield. Full Article
r Covid-19: Nightingale hospitals set to shut down after seeing few patients By feeds.bmj.com Published On :: 2020-05-07T06:50:46-07:00 The mothballing of Britain’s Nightingale hospitals, some of which have yet to treat a single covid-19 patient, has raised questions about whether resources to fight the pandemic were... Full Article
r Adil El-Tayar: renowned NHS transplant surgeon who died from covid-19 By feeds.bmj.com Published On :: 2020-05-07T06:51:23-07:00 bmj;369/may07_6/m1803/FAF1faPhoto credit: Abbas GhazanfarOn 25 March Adil El-Tayar, a renowned organ transplantation specialist, became the first working NHS surgeon to die from covid-19 in hospital... Full Article
r Covid-19: Trump says added deaths are necessary price for reopening US businesses By feeds.bmj.com Published On :: 2020-05-07T07:10:42-07:00 A rise in mortality is a price worth paying to restart the US economy, President Trump has said, as many states flout advice from scientists and reopen beaches, cinemas, or hair salons while new... Full Article
r Covid-19: Number of Germans infected could be 10 times higher than official estimates By feeds.bmj.com Published On :: 2020-05-07T07:16:18-07:00 The number of people in Germany infected with covid-19, could be 10 times higher than official government estimates, according to a new study by University of Bonn researchers.1The Heinsberg study is... Full Article
r The soaring joy of a family reunion By feeds.bmj.com Published On :: 2020-05-07T07:56:19-07:00 bmj;369/may07_9/m1832/FAF1faYara/ReutersThe meeting in Rome of Domenico di Massa with his granddaughter Cecilia for the first time in two months was echoed across Italy as families emerged onto the... Full Article
r Covid-19: Health needs of sex workers are being sidelined, warn agencies By feeds.bmj.com Published On :: 2020-05-07T08:46:13-07:00 Agencies have criticised the lack of action to protect the health needs of sex workers during the pandemic, with the English Collective of Prostitutes (ECP) warning of a “ticking time bomb of health... Full Article
r Myocardial Blood Flow and Myocardial Flow Reserve After Cardiac Transplantation: Mistakes in Diagnostic Value and Prognosis By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Full Article
r Reply: Clarifying the Utility of Myocardial Blood Flow and Myocardial Flow Reserve After Cardiac Transplantation By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Full Article
r Reversibility of 68Ga-FAPI-2 Trapping Might Prove an Asset for PET Quantitative Imaging By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Full Article
r Human Radiation Dosimetry for Orally and Intravenously Administered 18F-FDG By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Intravenous access is difficult in some patients referred for 18F-FDG PET imaging. Extravasation at the injection site and accumulation in central catheters can lead to limited tumor 18F-FDG uptake, erroneous quantitation, and significant image artifacts. In this study, we compared the human biodistribution and dosimetry for 18F-FDG after oral and intravenous administrations sequentially in the same subjects to ascertain the dosimetry and potential suitability of orally administered 18F-FDG as an alternative to intravenous administration. We also compared our detailed intravenous 18F-FDG dosimetry with older dosimetry data. Methods: Nine healthy volunteers (6 male and 3 female; aged 19–32 y) underwent PET/CT imaging after oral and intravenous administration of 18F-FDG. Identical preparation and imaging protocols (except administration route) were used for oral and intravenous studies. During each imaging session, 9 whole-body PET scans were obtained at 5, 10, 20, 30, 40, 50, 60, 120, and 240 min after 18F-FDG administration (370 ± 16 MBq). Source organ contours drawn using CT were overlaid onto registered PET images to extract time–activity curves. Time-integrated activity coefficients derived from time–activity curves were given as input to OLINDA/EXM for dose calculations. Results: Blood uptake after orally administered 18F-FDG peaked at 45–50 min after ingestion. The oral-to-intravenous ratios of 18F-FDG uptake for major organs at 45 min were 1.07 ± 0.24 for blood, 0.94 ± 0.39 for heart wall, 0.47 ± 0.12 for brain, 1.25 ± 0.18 for liver, and 0.84 ± 0.24 for kidneys. The highest organ-absorbed doses (μGy/MBq) after oral 18F-FDG administration were observed for urinary bladder (75.9 ± 17.2), stomach (48.4 ± 14.3), and brain (29.4 ± 5.1), and the effective dose was significantly higher (20%) than after intravenous administration (P = 0.002). Conclusion: 18F-FDG has excellent bioavailability after oral administration, but peak organ activities occur later than after intravenous injection. These data suggest PET at 2 h after oral 18F-FDG administration should yield images that are comparable in biodistribution to conventional clinical images acquired 1 h after injection. Oral 18F-FDG is a palatable alternative to intravenous 18F-FDG when venous access is problematic. Full Article
r First Evidence for a Dose-Response Relationship in Patients Treated with 166Ho Radioembolization: A Prospective Study By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 166Ho-microspheres have recently been approved for clinical use for hepatic radioembolization in the European Union. The aim of this study was to investigate the absorbed dose–response relationship and its association with overall survival for 166Ho radioembolization in patients with liver metastases. Methods: Patients treated in the HEPAR I and II studies who underwent an 18F-FDG PET/CT scan at baseline, a posttreatment 166Ho SPECT/CT scan, and another 18F-FDG PET/CT scan at the 3-mo follow-up were included for analysis. The posttreatment 166Ho-microsphere activity distributions were estimated with quantitative SPECT/CT reconstructions using a quantitative Monte Carlo–based method. The response of each tumor was based on the change in total lesion glycolysis (TLG) between baseline and follow-up and was placed into 1 of 4 categories, according to the PERCIST criteria, ranging from complete response to progressive disease. Patient-level response was grouped according to the average change in TLG per patient. The absorbed dose–response relationship was assessed using a linear mixed model to account for correlation of tumors within patients. Median overall survival was compared between patients with and without a metabolic liver response, using a log-rank test. Results: Thirty-six patients with a total of 98 tumors were included. The relation between tumor-absorbed dose and both tumor-level and patient-level response was explored. At a tumor level, a significant difference in geometric mean absorbed dose was found between complete response (232 Gy; 95% confidence interval [CI], 178–303 Gy; n = 32) and stable disease (147 Gy; 95% CI, 113–191 Gy; n = 28) (P = 0.01) and between complete response and progressive disease (117 Gy; 95% CI, 87–159 Gy; n = 21) (P = 0.0008). This constitutes a robust absorbed dose–response relationship. At a patient level, a significant difference was found between patients with complete or partial response (210 Gy; 95% CI, 161–274 Gy; n = 13) and patients with progressive disease (116 Gy; 95% CI, 81–165 Gy; n = 9) (P = 0.01). Patients were subsequently grouped according to their average change in TLG. Patients with an objective response (complete or partial) exhibited a significantly higher overall survival than nonresponding patients (stable or progressive disease) (median, 19 mo vs. 7.5 mo; log-rank, P = 0.01). Conclusion: These results confirm a significant absorbed dose–response relationship in 166Ho radioembolization. Treatment response is associated with a higher overall survival. Full Article
r TSPO Versus P2X7 as a Target for Neuroinflammation: An In Vitro and In Vivo Study By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Neuroinflammation is important in amyotrophic lateral sclerosis (ALS). The P2X7 receptor (P2X7R) is a promising target for neuroinflammation. The objective of this study was to compare 18F-DPA714, a second-generation translocator protein tracer, with 11C-JNJ717, a novel P2X7R tracer, in vitro and in vivo in ALS. Methods: For the in vitro portion of the study, autoradiography with 18F-DPA714 and 11C-JNJ717 was performed on human ALS brain sections in comparison to immunofluorescence with Iba1 and GFAP. For the in vivo portion, 3 male patients with early-stage ALS (59.3 ± 7.2 y old) and 6 healthy volunteers (48.2 ± 16.5 y old, 2 men and 4 women) underwent dynamic PET/MR scanning with 18F-DPA714 and 11C-JNJ717. Volume-of-distribution images were calculated using Logan plots and analyzed on a volume-of-interest basis. Results: Autoradiography showed no difference in 11C-JNJ717 binding but did show increased 18F-DPA714 binding in the motor cortex correlating with Iba1 expression (glial cells). Similar findings were observed in vivo, with a 13% increase in 18F-DPA714 binding in the motor cortex. Conclusion: In symptomatic ALS patients, 18F-DPA714 showed increased signal whereas 11C-JNJ717 was not elevated. Full Article
r Predictive Value of 18F-Florbetapir and 18F-FDG PET for Conversion from Mild Cognitive Impairment to Alzheimer Dementia By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 The present study examined the predictive values of amyloid PET, 18F-FDG PET, and nonimaging predictors (alone and in combination) for development of Alzheimer dementia (AD) in a large population of patients with mild cognitive impairment (MCI). Methods: The study included 319 patients with MCI from the Alzheimer Disease Neuroimaging Initiative database. In a derivation dataset (n = 159), the following Cox proportional-hazards models were constructed, each adjusted for age and sex: amyloid PET using 18F-florbetapir (pattern expression score of an amyloid-β AD conversion–related pattern, constructed by principle-components analysis); 18F-FDG PET (pattern expression score of a previously defined 18F-FDG–based AD conversion–related pattern, constructed by principle-components analysis); nonimaging (functional activities questionnaire, apolipoprotein E, and mini-mental state examination score); 18F-FDG PET + amyloid PET; amyloid PET + nonimaging; 18F-FDG PET + nonimaging; and amyloid PET + 18F-FDG PET + nonimaging. In a second step, the results of Cox regressions were applied to a validation dataset (n = 160) to stratify subjects according to the predicted conversion risk. Results: On the basis of the independent validation dataset, the 18F-FDG PET model yielded a significantly higher predictive value than the amyloid PET model. However, both were inferior to the nonimaging model and were significantly improved by the addition of nonimaging variables. The best prediction accuracy was reached by combining 18F-FDG PET, amyloid PET, and nonimaging variables. The combined model yielded 5-y free-of-conversion rates of 100%, 64%, and 24% for the low-, medium- and high-risk groups, respectively. Conclusion: 18F-FDG PET, amyloid PET, and nonimaging variables represent complementary predictors of conversion from MCI to AD. Especially in combination, they enable an accurate stratification of patients according to their conversion risks, which is of great interest for patient care and clinical trials. Full Article
r Multimodality Imaging of Inflammation and Ventricular Remodeling in Pressure-Overload Heart Failure By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Inflammation contributes to ventricular remodeling after myocardial ischemia, but its role in nonischemic heart failure is poorly understood. Local tissue inflammation is difficult to assess serially during pathogenesis. Although 18F-FDG accumulates in inflammatory leukocytes and thus may identify inflammation in the myocardial microenvironment, it remains unclear whether this imaging technique can isolate diffuse leukocytes in pressure-overload heart failure. We aimed to evaluate whether inflammation with 18F-FDG can be serially imaged in the early stages of pressure-overload–induced heart failure and to compare the time course with functional impairment assessed by cardiac MRI. Methods: C57Bl6/N mice underwent transverse aortic constriction (TAC) (n = 22), sham surgery (n = 12), or coronary ligation as an inflammation-positive control (n = 5). MRI assessed ventricular geometry and contractile function at 2 and 8 d after TAC. Immunostaining identified the extent of inflammatory leukocyte infiltration early in pressure overload. 18F-FDG PET scans were acquired at 3 and 7 d after TAC, under ketamine-xylazine anesthesia to suppress cardiomyocyte glucose uptake. Results: Pressure overload evoked rapid left ventricular dilation compared with sham (end-systolic volume, day 2: 40.6 ± 10.2 μL vs. 23.8 ± 1.7 μL, P < 0.001). Contractile function was similarly impaired (ejection fraction, day 2: 40.9% ± 9.7% vs. 59.2% ± 4.4%, P < 0.001). The severity of contractile impairment was proportional to histology-defined myocardial macrophage density on day 8 (r = –0.669, P = 0.010). PET imaging identified significantly higher left ventricular 18F-FDG accumulation in TAC mice than in sham mice on day 3 (10.5 ± 4.1 percentage injected dose [%ID]/g vs. 3.8 ± 0.9 %ID/g, P < 0.001) and on day 7 (7.8 ± 3.7 %ID/g vs. 3.0 ± 0.8 %ID/g, P = 0.006), though the efficiency of cardiomyocyte suppression was variable among TAC mice. The 18F-FDG signal correlated with ejection fraction (r = –0.75, P = 0.01) and ventricular volume (r = 0.75, P < 0.01). Western immunoblotting demonstrated a 60% elevation of myocardial glucose transporter 4 expression in the left ventricle at 8 d after TAC, indicating altered glucose metabolism. Conclusion: TAC induces rapid changes in left ventricular geometry and contractile function, with a parallel modest infiltration of inflammatory macrophages. Metabolic remodeling overshadows inflammatory leukocyte signal using 18F-FDG PET imaging. More selective inflammatory tracers are requisite to identify the diffuse local inflammation in pressure overload. Full Article
r Preoperative Localization of Adenomas in Primary Hyperparathyroidism: The Value of 11C-Choline PET/CT in Patients with Negative or Discordant Findings on Ultrasonography and 99mTc-Sestamibi SPECT/CT By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 We aimed to assess the value of 11C-choline PET in patients with primary hyperparathyroidism and negative or discordant results on 99mTc-sestamibi imaging and neck ultrasound. Methods: Eighty-seven such patients were assessed and subsequently underwent parathyroidectomy. PET/CT image data were analyzed semiquantitatively using SUVmax and SUV ratios (target to contralateral thyroid gland and carotid artery). A positive PET/CT result was defined as focal uptake significantly higher than regular thyroid tissue. Ectopic foci were also considered positive. Inconclusive PET/CT cases were defined as a lesion with uptake equal to normal thyroid tissue. If no prominent or ectopic uptake was detectable, the PET/CT result was considered negative. Results: When dichotomizing the 11C-choline PET/CT imaging results by defining lesions with both positive and inconclusive uptake as positive, we found 84 of 92 lesions (91.3%) to have true-positive uptake whereas 8 lesions (8.7%) had false-positive uptake. One lesion showed false-negative uptake; the sensitivity was 98.8%. The corresponding positive predictive value for lesions was 91.3%. The mean SUVmax was 6.15 ± 4.92 in 72 lesions with positive uptake (70 patients) and 2.96 ± 2.32 in 20 lesions with inconclusive uptake (18 patients). Conclusion: These results in a large group of patients indicate that 11C-choline PET/CT is a promising tool for parathyroid adenoma localization when ultrasound and 99mTc-sestamibi imaging yield negative or discordant results. Full Article
r 18F-Fluorocholine PET/CT in Primary Hyperparathyroidism: Superior Diagnostic Performance to Conventional Scintigraphic Imaging for Localization of Hyperfunctioning Parathyroid Glands By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Primary hyperparathyroidism (PHPT) is a common endocrine disorder, definitive treatment usually requiring surgical removal of the offending parathyroid glands. To perform focused surgical approaches, it is necessary to localize all hyperfunctioning glands. The aim of the study was to compare the efficiency of established conventional scintigraphic imaging modalities with emerging 18F-fluorocholine PET/CT imaging in preoperative localization of hyperfunctioning parathyroid glands in a larger series of PHPT patients. Methods: In total, 103 patients with PHPT were imaged preoperatively with 18F-fluorocholine PET/CT and conventional scintigraphic imaging methods, consisting of 99mTc-sestamibi SPECT/CT, 99mTc-sestamibi/pertechnetate subtraction imaging, and 99mTc-sestamibi dual-phase imaging. The results of histologic analysis, as well as intact parathyroid hormone and serum calcium values obtained 1 d after surgery and on follow-up, served as the standard of truth for evaluation of imaging results. Results: Diagnostic performance of 18F-fluorocholine PET/CT surpassed conventional scintigraphic methods (separately or combined), with calculated sensitivity of 92% for PET/CT and 39%–56% for conventional imaging (65% for conventional methods combined) in the entire patient group. Subgroup analysis, differentiating single and multiple hyperfunctioning parathyroid glands, showed PET/CT to be most valuable in the group with multiple hyperfunctioning glands, with sensitivity of 88%, whereas conventional imaging was significantly inferior, with sensitivity of 22%–34% (44% combined). Conclusion: 18F-fluorocholine PET/CT is a diagnostic modality superior to conventional imaging methods in patients with PHPT, allowing for accurate preoperative localization. Full Article
r PET Imaging of Pancreatic Dopamine D2 and D3 Receptor Density with 11C-(+)-PHNO in Type 1 Diabetes By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Type 1 diabetes mellitus (T1DM) has traditionally been characterized by a complete destruction of β-cell mass (BCM); however, there is growing evidence of possible residual BCM present in T1DM. Given the absence of in vivo tools to measure BCM, routine clinical measures of β-cell function (e.g., C-peptide release) may not reflect BCM. We previously demonstrated the potential utility of PET imaging with the dopamine D2 and D3 receptor agonist 3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4]oxazin-9-ol (11C-(+)-PHNO) to differentiate between healthy control (HC) and T1DM individuals. Methods: Sixteen individuals participated (10 men, 6 women; 9 HCs, 7 T1DMs). The average duration of diabetes was 18 ± 6 y (range, 14–30 y). Individuals underwent PET/CT scanning with a 120-min dynamic PET scan centered on the pancreas. One- and 2-tissue-compartment models were used to estimate pancreas and spleen distribution volume. Reference region approaches (spleen as reference) were also investigated. Quantitative PET measures were correlated with clinical outcome measures. Immunohistochemistry was performed to examine colocalization of dopamine receptors with endocrine hormones in HC and T1DM pancreatic tissue. Results: C-peptide release was not detectable in any T1DM individuals, whereas proinsulin was detectable in 3 of 5 T1DM individuals. Pancreas SUV ratio minus 1 (SUVR-1) (20–30 min; spleen as reference region) demonstrated a statistically significant reduction (–36.2%) in radioligand binding (HCs, 5.6; T1DMs, 3.6; P = 0.03). Age at diagnosis correlated significantly with pancreas SUVR-1 (20–30 min) (R2 = 0.67, P = 0.025). Duration of diabetes did not significantly correlate with pancreas SUVR-1 (20–30 min) (R2 = 0.36, P = 0.16). Mean acute C-peptide response to arginine at maximal glycemic potentiation did not significantly correlate with SUVR-1 (20–30 min) (R2 = 0.57, P = 0.05), nor did mean baseline proinsulin (R2 = 0.45, P = 0.10). Immunohistochemistry demonstrated colocalization of dopamine D3 receptor and dopamine D2 receptor in HCs. No colocalization of the dopamine D3 receptor or dopamine D2 receptor was seen with somatostatin, glucagon, or polypeptide Y. In a separate T1DM individual, no immunostaining was seen with dopamine D3 receptor, dopamine D2 receptor, or insulin antibodies, suggesting that loss of endocrine dopamine D3 receptor and dopamine D2 receptor expression accompanies loss of β-cell functional insulin secretory capacity. Conclusion: Thirty-minute scan durations and SUVR-1 provide quantitative outcome measures for 11C-(+)-PHNO, a dopamine D3 receptor–preferring agonist PET radioligand, to differentiate BCM in T1DM and HCs. Full Article
r Theranostics Targeting Fibroblast Activation Protein in the Tumor Stroma: 64Cu- and 225Ac-Labeled FAPI-04 in Pancreatic Cancer Xenograft Mouse Models By jnm.snmjournals.org Published On :: 2020-04-01T06:00:28-07:00 Fibroblast activation protein (FAP), which promotes tumor growth and progression, is overexpressed in cancer-associated fibroblasts of many human epithelial cancers. Because of its low expression in normal organs, FAP is an excellent target for theranostics. In this study, we used radionuclides with relatively long half-lives, 64Cu (half-life, 12.7 h) and 225Ac (half-life, 10 d), to label FAP inhibitors (FAPIs) in mice with human pancreatic cancer xenografts. Methods: Male nude mice (body weight, 22.5 ± 1.2 g) were subcutaneously injected with human pancreatic cancer cells (PANC-1, n = 12; MIA PaCa-2, n = 8). Tumor xenograft mice were investigated after the intravenous injection of 64Cu-FAPI-04 (7.21 ± 0.46 MBq) by dynamic and delayed PET scans (2.5 h after injection). Static scans 1 h after the injection of 68Ga-FAPI-04 (3.6 ± 1.4 MBq) were also acquired for comparisons using the same cohort of mice (n = 8). Immunohistochemical staining was performed to confirm FAP expression in tumor xenografts using an FAP-α-antibody. For radioligand therapy, 225Ac-FAPI-04 (34 kBq) was injected into PANC-1 xenograft mice (n = 6). Tumor size was monitored and compared with that of control mice (n = 6). Results: Dynamic imaging of 64Cu-FAPI-04 showed rapid clearance through the kidneys and slow washout from tumors. Delayed PET imaging of 64Cu-FAPI-04 showed mild uptake in tumors and relatively high uptake in the liver and intestine. Accumulation levels in the tumor or normal organs were significantly higher for 64Cu-FAPI-04 than for 68Ga-FAPI-04, except in the heart, and excretion in the urine was higher for 68Ga-FAPI-04 than for 64Cu-FAPI-04. Immunohistochemical staining revealed abundant FAP expression in the stroma of xenografts. 225Ac-FAPI-04 injection showed significant tumor growth suppression in the PANC-1 xenograft mice, compared with the control mice, without a significant change in body weight. Conclusion: This proof-of-concept study showed that 64Cu-FAPI-04 and 225Ac-FAPI-04 could be used in theranostics for the treatment of FAP-expressing pancreatic cancer. α-therapy targeting FAP in the cancer stroma is effective and will contribute to the development of a new treatment strategy. Full Article