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Anaplastic thyroid cancer is a rare but devastating malignancy. Anaplastic thyroid cancer cells exhibit the Warburg effect by preferentially undergoing glycolysis even in aerobic conditions, leading to high glucose use. Here we assess if targeted inhibition of glycolysis can diminish anaplastic thyroid cancer growth and improve outcomes.Human anaplastic thyroid cancer cell line 8505C was grown in medium containing high (25 mmol/L) or low (3 mmol/L) glucose concentration and hexokinase II inhibitor 3-bromopyruvate (200 μM). Cellular proliferation, migration, and invasion were measured. An orthotopic xenograft model of anaplastic thyroid cancer was generated in nude mice using 8505C cells. Animals were provided standard chow or a ketogenic diet and treated with 3-bromopyruvate (1.8 mg/kg). Overall survival time was monitored. Necropsies were performed to harvest tumors for analysis.Growth of 8505C in low-glucose medium with 3-bromopyruvate decreased cell proliferation by 89%, migration by 44%, and invasion by 73% (P.001 for all) compared with high glucose. Animals concomitantly receiving a ketogenic diet and 3-bromopyruvate exhibited smaller tumor volumes (P = .03), slower tumor growth rates (P = .01), and improved overall survival (P = .006) compared with standard-diet control subjects. Monotherapy with a ketogenic diet or 3-bromopyruvate alone did not reduce tumor size or increase survival over the standard-diet control group.Glycolytic inhibition with 3-bromopyruvate inhibits tumor growth and extends survival in a murine model of anaplastic thyroid cancer when combined with the ketogenic diet. Thus, targeted glycolytic inhibition of anaplastic thyroid cancer exhibits context-specific utility and may only be effective during ketosis induced by dietary restriction of glycolytic inputs.

Background: Single photon emission computed tomography (SPECT) has limited ability to identify multivessel and microvascular coronary artery disease. Gamma cameras with cadmium zinc telluride detectors allow the quantification of absolute myocardial blood flow (MBF) and myocardial flow reserve (MFR). However, evidence of its accuracy is limited, and of its reproducibility is lacking. We aimed to validate 99m Tc-sestamibi SPECT MBF and MFR using standard and spline-fitted reconstruction algorithms compared with 13 N-ammonia positron emission tomography in a cohort of patients with known or suspected coronary artery disease and to evaluate the reproducibility of this technique. Methods: Accuracy was assessed in 34 participants who underwent dynamic 99m Tc-sestamibi SPECT and 13 N-ammonia positron emission tomography and reproducibility in 14 participants who underwent 2 99m Tc-sestamibi SPECT studies, all within 2 weeks. A rest/pharmacological stress single-day SPECT protocol was performed. SPECT images were reconstructed using a standard ordered subset expectation maximization (OSEM) algorithm with (N=21) and without (N=30) application of spline fitting. SPECT MBF was quantified using a net retention kinetic model‚ and MFR was derived as the stress/rest MBF ratio. Results: SPECT global MBF with splines showed good correlation with 13 N-ammonia positron emission tomography (r=0.81, P P P P =0.07, for MBF and MFR, respectively). Reproducibility of global MBF estimates with splines in paired SPECT scans was good (r=0.77, P P P =0.3). There were no significant differences in MBF or MFR between the 2 reproducibility scans independently of the reconstruction algorithm ( P >0.05 for all). Conclusions: MBF and MFR quantification using 99m Tc-sestamibi cadmium zinc telluride SPECT with spatiotemporal spline fitting improved the correlation with 13 N-ammonia positron emission tomography flow estimates and test/retest reproducibility. The use of splines may represent an important step toward the standardization of SPECT flow estimation.

OBJECTIVES: The goals of this study were to characterize myocardial composition during the active and remission phases of light-chain (AL) cardiac amyloidosis. BACKGROUND: Cardiac dysfunction in AL amyloidosis is characterized by dual insults to the myocardium from infiltration and toxicity from light chains during the active phase and by infiltration alone in the remission phase. METHODS: Prospectively enrolled subjects with cardiac AL amyloidosis (21 remission AL amyloidosis; age: 63.4 ± 7.3 years; 47.6% male; and 48 active AL amyloidosis; age: 62.5 ± 7.4 years; 60.4% male) underwent contrast-enhanced cardiac magnetic resonance with T(1) and T(2) mapping and measurement of extracellular volume (ECV). By definition, serum free light-chain levels were normal for at least 1 year following successful AL therapy in the remission group and abnormal in the active group. RESULTS: Myocardial ECV was similarly expanded in the remission and active AL amyloidosis groups (0.488 ± 0.082 vs 0.519 ± 0.083, respectively; P = 0.15). However, myocardial T(2) relaxation times (47.7 ± 3.2 ms vs 45.5 ± 3.0 ms; P = 0.008) as well as native T(1) times (1,368 ms [IQR: 1,290–1,422 ms] vs 1,264 ms [IQR: 1,203–1,380 ms]; P = 0.024) were significantly higher in the remission compared to the active AL amyloidosis group. CONCLUSIONS: Myocardial ECV is substantially expanded in the active AL and remission AL cardiac amyloidosis groups, but native T(1) values were higher, suggesting a different myocardial composition. There is no evidence of myocardial edema in active AL cardiac amyloidosis. Future phenotyping studies of AL cardiac amyloidosis need to consider complementary myocardial markers that define the interstitial milieu in addition to changes in extracellular volume. (Molecular Imaging of Primary Amyloid Cardiomyopathy; NCT02641145)

Breathing motion can displace internal organs by up to several cm; as such, it is a primary factor limiting image quality in medical imaging. Motion can also complicate matters when trying to fuse images from different modalities, acquired at different locations and/or on different days. Currently available devices for monitoring breathing motion often do so indirectly, by detecting changes in the outline of the torso rather than the internal motion itself, and these devices are often fixed to floors, ceilings or walls, and thus cannot accompany patients from one location to another. We have developed small ultrasound-based sensors, referred to as ‘organ configuration motion’ (OCM) sensors, that attach to the skin and provide rich motion-sensitive information. In the present work we tested the ability of OCM sensors to enable respiratory gating during in vivo PET imaging. A motion phantom involving an FDG solution was assembled, and two cancer patients scheduled for a clinical PET/CT exam were recruited for this study. OCM signals were used to help reconstruct phantom and in vivo data into time series of motion-resolved images. As expected, the motion-resolved images captured the underlying motion. In Patient #1, a single large lesion proved to be mostly stationary through the breathing cycle. However, in Patient #2, several small lesions were mobile during breathing, and our proposed new approach captured their breathing-related displacements. In summary, a relatively inexpensive hardware solution was developed here for respiration monitoring. Because the proposed sensors attach to the skin, as opposed to walls or ceilings, they can accompany patients from one procedure to the next, potentially allowing data gathered in different places and at different times to be combined and compared in ways that account for breathing motion.