Gastroparesis versus dyspepsia by intragastric meal distribution: new diagnostics and definitions ahead.

Gastroparesis often presents a challenge to the practicing gastroenterologist. Postprandial symptoms with nausea and vomiting may not only lead to nutritional and metabolic consequences, but also significant disruption of social activities that often center around food. The treatment options that affect gastric function are limited and often disappointing. The female predominance, the mostly idiopathic and idiosyncratic nature of the illness, often with some common psychiatric co-morbidity, parallels other functional disorders of the gastrointestinal tract. These parallels have provided the rationale for studies investigating alternative diagnostic features of the gastric emptying test as employed in the clinical setting. Hence, not only the regular cut-offs of 60% or 10% gastric retention of a meal at 2 and 4 h, but also a new concept, the intragastric meal distribution at time 0 (IMD0) is now introduced as a plausible diagnostic feature that should be more aligned with the patients' symptoms as they appear in close connection with the meal. Impaired gastric accommodation with absence of fundic relaxation followed by dumping of the meal into antrum is suggested to be diagnostic for functional dyspepsia and gastroparesis. The diagnostic cut-off is considered when more than 57% of the meal is distributed to the distal part of the stomach immediately on food intake. This new diagnostic feature of the gastric emptying profile lend support to better understanding of the patients' symptoms and provides a new basis for pharmacological treatment options in gastroparesis that may provide an improved quality of life in affected individuals.

Effect of blood glucose level on standardized uptake value (SUV) in 18F- FDG PET-scan: a systematic review and meta-analysis of 20,807 individual SUV measurements.

OBJECTIVES: To evaluate the effect of pre-scan blood glucose levels (BGL) on standardized uptake value (SUV) in 18F-FDG-PET scan. METHODS: A literature review was performed in the MEDLINE, Embase, and Cochrane library databases. Multivariate regression analysis was performed on individual datum to investigate the correlation of BGL with SUVmax and SUVmean adjusting for sex, age, body mass index (BMI), diabetes mellitus diagnosis, 18F-FDG injected dose, and time interval. The ANOVA test was done to evaluate differences in SUVmax or SUVmean among five different BGL groups (< 110, 110-125, 125-150, 150-200, and > 200 mg/dl). RESULTS: Individual data for a total of 20,807 SUVmax and SUVmean measurements from 29 studies with 8380 patients was included in the analysis. Increased BGL is significantly correlated with decreased SUVmax and SUVmean in brain (p < 0.001, p < 0.001,) and muscle (p < 0.001, p < 0.001) and increased SUVmax and SUVmean in liver (p = 0.001, p = 0004) and blood pool (p = 0.008, p < 0.001). No significant correlation was found between BGL and SUVmax or SUVmean in tumors. In the ANOVA test, all hyperglycemic groups had significantly lower SUVs compared with the euglycemic group in brain and muscle, and significantly higher SUVs in liver and blood pool. However, in tumors only the hyperglycemic group with BGL of > 200 mg/dl had significantly lower SUVmax. CONCLUSION: If BGL is lower than 200 mg/dl no interventions are needed for lowering BGL, unless the liver is the organ of interest. Future studies are needed to evaluate sensitivity and specificity of FDG-PET scan in diagnosis of malignant lesions in hyperglycemia.

Dynamic gadoxetate-enhanced MRI for the assessment of total and segmental liver function and volume in primary sclerosing cholangitis.

PURPOSE: To evaluate dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) for the assessment of global and segmental liver volume and function in patients with primary sclerosing cholangitis (PSC), and to explore the heterogeneous distribution of liver function in this patient group. MATERIALS AND METHODS: Twelve patients with primary sclerosing cholangitis (PSC) and 20 healthy volunteers were examined using DHCE-MRI with Gd-EOB-DTPA. Segmental and total liver volume were calculated, and functional parameters (hepatic extraction fraction [HEF], input relative blood-flow [irBF], and mean transit time [MTT]) were calculated in each liver voxel using deconvolutional analysis. In each study subject, and incongruence score (IS) was constructed to describe the mismatch between segmental function and volume. Among patients, the liver function parameters were correlated to bile duct obstruction and to established scoring models for liver disease. RESULTS: Liver function was significantly more heterogeneously distributed in the patient group (IS 1.0 versus 0.4). There were significant correlations between biliary obstruction and segmental functional parameters (HEF rho -0.24; irBF rho -0.45), and the Mayo risk score correlated significantly with the total liver extraction capacity of Gd-EOB-DTPA (rho -0.85). CONCLUSION: The study demonstrates a new method to quantify total and segmental liver function using DHCE-MRI in patients with PSC.

Can Na18F PET/CT be used to study bone remodeling in the tibia when patients are being treated with a Taylor Spatial Frame?

Monitoring and quantifying bone remodeling are of interest, for example, in correction osteotomies, delayed fracture healing pseudarthrosis, bone lengthening, and other instances. Seven patients who had operations to attach an Ilizarov-derived Taylor Spatial Frame to the tibia gave informed consent. Each patient was examined by Na(18)F PET/CT twice, at approximately six weeks and three months after the operation. A validated software tool was used for the following processing steps. The first and second CT volumes were aligned in 3D and the respective PET volumes were aligned accordingly. In the first PET volume spherical volumes of interest (VOIs) were delineated for the crural fracture and normal bone and transferred to the second PET volume for SUVmax evaluation. This method potentially provides clinical insight into questions such as, when has the bone remodeling progressed well enough to safely remove the TSF? and when is intervention required, in a timelier manner than current methods? For example, in two patients who completed treatment, the SUVmax between the first and second PET/CT examination decreased by 42% and 13%, respectively. Further studies in a larger patient population are needed to verify these preliminary results by correlating regional Na(18)F PET measurements to clinical and radiological findings.

The distribution of FDG at PET examinations constitutes a relative mechanism: significant effects at activity quantification in patients with a high muscular uptake.

PURPOSE: At (18)F-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) examinations a high tracer uptake of the skeletal muscles is sometimes encountered which can lead to reduced uptake in pathological lesions. This was evaluated in retrospect in patients being recalled for a repeat examination after reducing the muscular uptake. METHODS: Ten patients with increased muscular tracer uptake were examined with FDG PET/CT on two occasions with a mean of 6 days. All patients showed at least one pathological lesion with increased tracer uptake. The muscular uptake was reduced at the second examination by informing the patient to refrain from physical activity together with pretreatment with diazepam. The maximum standardized uptake value (SUV(max)) of the pathological lesion and SUV(mean) of certain skeletal muscles, liver, spleen, lungs, blood and certain bone marrow portions were calculated. RESULTS: In all patients, the muscular uptake was reduced to a normal level at visual evaluation as well as at comparison of SUVs with 25 consecutive clinical patients exhibiting a normal FDG distribution (p < 0.001). The mean lesion SUV(max) increased from 2.4 to 3.7 (54 %) between the examinations (p < 0.05). All reference tissues/organs showed a significant increase of SUV at the second examination. Relating lesion SUV(max) to the activity of any of the reference tissues/organs there was no significant difference between the studies. CONCLUSION: The distribution of FDG constitutes a relative mechanism. This must be especially considered at longitudinal examinations in the same patient at therapy evaluations. In examinations with a somehow distorted general distribution of the activity, it may be more relevant to relate the lesion activity to a reference tissue/organ than relying on SUV assessments.

Involvement of endogenous glucagon-like peptide-1 in regulation of gastric motility and pancreatic endocrine secretion.

OBJECTIVE: To study the role of endogenous glucagon-like peptide-1 (GLP-1) on gastric emptying rates of a solid meal as well as postprandial hormone secretion and glucose disposal. MATERIAL AND METHODS: In nine healthy subjects, gastric emptying of a 310-kcal radio-labelled solid meal and plasma concentrations of insulin, glucagon and glucose were measured during infusion of saline or the GLP-1 receptor antagonist exendin(9-39)amide (Ex(9-39)) at 300 pmol·kg(-1)·min(-1). RESULTS: Ex(9-39) infusion had no effect on the total gastric emptying curve, but changed the intra-gastric distribution of the meal. During infusion of Ex(9-39), more content stayed in the upper stomach (79.1 ± 2.5% of total during Ex(9-39) compared to 66.6 ± 5.7% during saline at 5 min). During Ex(9-39) infusion, higher concentrations of plasma glucagon were measured both before (after 40 min of Ex(9-39) infusion the glucagon level was 15.1 ± 0.7 pmol·L(-1) compared to 5.4 ± 1.4 during saline) and after the meal, and postprandial GLP-1 levels increased. Basal insulin and glucose levels were not affected by Ex(9-39), but the postprandial rise of insulin and glucose enhanced during Ex(9-39). CONCLUSIONS: Endogenous GLP-1 is involved in the regulation of gastric motility in relation to meal intake and also in the regulation of postprandial insulin and glucose levels. Furthermore, endogenous GLP-1 seems to tonically restrain glucagon secretion.

Radionuclide hysterosalpingography is not a reliable tool for investigation of fallopian tube transport--a controlled randomized study using particles of two sizes during three different parts of the menstrual cycle.

BACKGROUND/AIMS: Earlier studies with radionuclide hysterosalpingography (RN-HSG) using either small or large particles have shown different results. Some studies have questioned the clinical relevance of RN-HSG. The aim of this study was to evaluate the RN-HSG method using two different sizes of radio-labelled particles during different parts of the menstrual cycle. METHODS: Ten healthy women, 28-40 years of age (mean 34.5), with proven fertility, regular menstrual cycle, not using oral contraceptives and due to undergo laparoscopic sterilization, were randomized to RN-HSG after deposition of a solution with either small Albures or large MAASOL, (99m)Tc-radio-labelled particles into the cervix uteri. Investigations were, for every patient, performed during the follicular, peri-ovulatory and mid-luteal parts of the menstrual cycle. Transport of radioactivity from cervix to uterus and Fallopian tubes was evaluated. RESULTS: The RN-HSG investigations could not show any difference between the two different sizes of radio-labelled particles. Transport of radioactivity to the Fallopian tube was seen only in some cases and most frequently during the peri-ovulatory period. CONCLUSION: We found the RN-HSG investigations inconclusive. The RN-HSG method does not seem to be a reliable tool for the investigation of Fallopian tube transport.

Inhalation anesthesia increases V/Q regional heterogeneity during spontaneous breathing in healthy subjects.

BACKGROUND: The underlying mechanism for the increased alveolar-arterial oxygen tension difference resulting from almost all forms of general anesthesia is unknown. We hypothesized that inhalation anesthesia influences the intrapulmonary distribution of ventilation (V) and perfusion (Q), leading to less advantageous V/Q matching. METHODS: Ten healthy volunteers were studied in supine position on two separate occasions, once awake and once during mild anesthesia (sevoflurane inhalation) with maintained spontaneous breathing. On both occasions, the distribution of V and Q were simultaneously imaged using single photon emission computed tomography. V was tagged with [Tc]-labeled carbon particle aerosol and Q with [In]-labeled macroaggregates of human albumin. Atelectasis formation during anesthesia was prevented using low concentrations of oxygen in inhaled air. RESULTS: Mean V and Q distributions in the ventral-to-dorsal direction, measured in 20 equally spaced volumes of interest and in three regions of interest of equal volume, did not differ between conditions. Anesthesia, when compared with the awake state, significantly decreased the total heterogeneity of the Q distribution (P = 0.002, effect size 1.16) but did not alter V (P = 0.37, effect size 0.41). The corresponding V/Q total heterogeneity was higher under anesthesia (P = 0.002, effect size 2.64). Compared to the awake state, the V/Q frequency distribution under anesthesia became wider (P = 0.009, 1.76 effect size) with a tendency toward low V/Q ratios. CONCLUSION: Inhalation anesthesia alone affects Q but not V, suggesting that anesthesia has a direct effect on the active regulatory mechanism coordinating Q with V, leading to less favorable V/Q matching.

Lung ventilation and perfusion in prone and supine postures with reference to anesthetized and mechanically ventilated healthy volunteers.

BACKGROUND: The literature on ventilation (V) and lung perfusion (Q) distributions during general anesthesia and controlled mechanical ventilation in supine and prone position is contradictory. The authors aimed to investigate whether V, Q, and ventilation to perfusion ratio (V/Q ratio) matching in anesthetized and mechanically ventilated volunteers are gravity dependent irrespective of posture. METHODS: Seven healthy volunteers were studied at two different occasions during general anesthesia and controlled mechanical ventilation. One occasion studied ventral to dorsal V and Q distributions in the supine posture and the other in the prone posture. Imaging was performed in supine posture at both occasions. A dual radiotracer technique and single photon emission computed tomography were used. V and Q were simultaneously tagged with Tc-Technegas (Tetley Manufacturing Ltd., Sydney, Australia) and In-labeled macroaggregates of human albumin (TechneScan LyoMAA, Mallinckrodt Medica, Petten, The Netherlands), respectively. RESULTS: No differences in V between postures were observed. Q differed between postures, being more uniform over different lung regions in prone posture and dependent in supine posture. The contribution of the vertical direction to the total V/Q ratio heterogeneity was larger in supine (31.4%) than in prone (16.4%) (P = 0.0639, two-tailed, paired t test) posture. CONCLUSIONS: During mechanical ventilation, prone posture favors a more evenly distributed Q between lung regions. V distribution is independent of posture. This results in a tendency toward lower V/Q gradients in the ventral to dorsal direction in prone compared with supine posture.

Presence of human papillomavirus (HPV) in vulvar squamous cell carcinoma (VSCC) and sentinel node.

OBJECTIVE: To investigate the presence of HPV in VSCC and sentinel nodes (SN) in patients in Sweden and the possible influence of HPV on prognosis. PATIENTS AND MATERIALS: Primary tumors from 75 VSCC patients undergoing the SN procedure and SNs from 69 patients were tested for HPV DNA. Analyses were performed by PCR using general (GP5+/6+ and CPI/IIG) type-specific primers, and sequencing in paraffin-embedded VSCC and SN. RESULTS: HPV was detected in 23/75 (31%) of the tumors and in 10/23 (43%) of the SNs in patients with HPV-positive tumors and in one SN of a patient with an HPV-negative tumor. Patients with HPV-positive VSCC were younger at diagnosis (p<0.001) and had better survival (p=0.030), adjusted for age and lesion size, than those with HPV-negative tumors. In patients with HPV-positive tumors, SNs with metastases were more frequently HPV positive (5/5) than those without metastases (5/18) (p=0.007). CONCLUSION: The rate of 31% HPV-positive VSCC in Sweden is similar to other reports. As far as we know, HPV in SN in VSCC never been investigated previously. The differences in age, tumor size, prevalence of HPV in SN and survival of patients with HPV-positive and negative VSCC support the assumption that VSCC develops through two different pathways, with better survival for patients with HPV-positive tumors. Presence of HPV DNA in SN was related to metastatic disease but did not affect survival in this study.

Interobserver and intraobserver variability in the response evaluation of cancer therapy according to RECIST and WHO-criteria.

BACKGROUND: Response Evaluation Criteria In Solid Tumors (RECIST) and WHO-criteria are used to evaluate treatment effects in clinical trials. The purpose of this study was to examine interobserver and intraobserver variations in radiological response assessment using these criteria. MATERIAL AND METHODS: Thirty-nine patients were eligible. Each patient's series of CT images were reviewed. Each patient was classified into one of four categories according RECIST and WHO-criteria. To examine interobserver variation, response classifications were independently obtained by two radiologists. One radiologist repeated the procedure on two additional different occasions to examine intraobserver variation. Kappa statistics was applied to examine agreement. RESULTS: Interobserver variation using RECIST and WHO-criteria were 0.53 (95% CI 0.33-0.72) and 0.60 (0.39-0.80), respectively. Response rates (RR) according to RECIST obtained by reader A and reader B were 33% and 21%, respectively. RR according to WHO-criteria obtained by reader A and reader B were 33% and 23% respectively. Intraobserver variation using RECIST and WHO-criteria ranged between 0.76-0.96 and 0.86-0.91, respectively. CONCLUSION: Radiological tumor response evaluation according to RECIST and WHO-criteria are subject to considerable inter- and intraobserver variability. Efforts are necessary to reduce inconsistencies from current response evaluation criteria.

A Novel Sentinel Lymph Node Approach in Oral Squamous Cell Carcinoma.

BACKGROUND: Occult metastases are common in patients with oral squamous cell carcinoma (OSCC) which is why elective neck dissection, adjuvant radiotherapy or watchful waiting have been treatment options after surgical removal of the primary tumour. Sentinel lymph node biopsy (SLNB) has lately emerged as a novel possibility in treatment planning. OBJECTIVES: To establish a reliable and clinically useful protocol for SLNB in staging/elective neck dissection in oral cancer. METHODS: Fourteen consecutive patients with T1-T2 N0 oral cancer were enrolled when scheduled for elective neck dissection. RESULTS: This study outlines various techniques for improving SLNB in head and neck cancer. After evaluation, a combination of techniques was found to constitute a reliable, clinically adaptable work concept. The suggested procedure starts with the pre-surgical injection of radioactive technetium 99Tcm carried on tilmanocept (Lymphoseek ®) at the tumour site. The radioactivity in the lymph node is then visualized preoperatively with Single Photon Emission Computed Tomography (SPECT/CT). Intraoperatively, indocyanine green (ICG) is injected and a sentinel node is visualized with near-infrared light. To support the sentinel node detection, the surgeon uses a hand-held gamma detection probe. This approach results in a reproducible and reliable detection of sentinel nodes. CONCLUSION: This paper presents a novel protocol for the identification of the sentinel node in the head and neck region. The protocol additionally enables the use of flow cytometry analysis of resected lymph nodes.

Complete and long-lasting clinical responses in immune checkpoint inhibitor-resistant, metastasized melanoma treated with adoptive T cell transfer combined with DC vaccination.

Development of T cell-directed immune checkpoint inhibitors (ICI) has revolutionized metastatic melanoma (MM) therapy, but <50% of treated patients experience durable responses. This phase I trial (NCT01946373) investigates the safety/feasibility of tumor-infiltrating lymphocyte (TIL) adoptive cell therapy (ACT) combined with dendritic cell (DC) vaccination in MM patients progressing on ICI. An initial cohort (5 patients) received TIL therapy alone to evaluate safety and allow for optimization of TIL expansion protocols. A second cohort (first-in-man, 5 patients) received TIL combined with autologous tumor lysate-loaded DC vaccination. All patients received cyclophosphamide/fludarabine preconditioning prior to, and intravenous (i.v.) IL-2 after, TIL transfer. The DC vaccine was given as five intradermal injections after TIL and IL-2 administration. [18F]-FDG PET/CT radiology was performed to evaluate clinical response, according to RECIST 1.1 (on the CT part). Immunological monitoring was performed by flow cytometry and T-cell receptor (TCR) sequencing. In the safety/optimization cohort, all patients had a mixed response or stable disease, but none durable. In the combination cohort, two patients experienced complete responses (CR) that are still ongoing (>36 and >18 months, respectively). In addition, two patients had partial responses (PR), one still ongoing (>42 months) with only a small bone-lesion remaining, and one of short duration (<4 months). One patient died early during treatment and did not receive DC. Long-lasting persistency of the injected TILs was demonstrated in blood. In summary, we report clinical responses by TIL therapy combined with DC vaccination in 4 out of 4 treated MM patients who previously failed ICI.

Differences at brain SPECT between depressed females with and without adult ADHD and healthy controls: etiological considerations.

BACKGROUND: Comorbidity between Attention Deficit Hyperactivity Disorder (ADHD) and mood disorders is common. Alterations of the cerebellum and frontal regions have been reported in neuro-imaging studies of ADHD and major depression. METHODS: Thirty chronically depressed adult females of whom 16 had scores below, and 14 scores above, cut-offs on the 25-items Wender Utah Retrospective Scale (WURS-25) and the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) were divided into subgroups designated "Depression" and "Depression + ADHD", respectively. Twenty-one of the patients had some audiological symptom, tinnitus and/or hearing impairment. The patients were investigated with other rating scales and 99mTc-HMPAO SPECT. Controls for 99mTc-HMPAO SPECT were 16 healthy females. SPECT was analyzed by both statistical parametric mapping (SPM2) and the computerized brain atlas (CBA). Discriminant analysis was performed on the volumes of interest generated by the CBA, and on the scores from rating scales with the highest group differences. RESULTS: The mean score of a depression rating scale (MADRS-S) was significantly lower in the "Depression" subgroup compared to in the "Depression + ADHD" subgroup. There was significantly decreased tracer uptake within the bilateral cerebellum at both SPM and CBA in the "Depression + ADHD" subgroup compared to in the controls. No decrease of cerebellar tracer uptake was observed in "Depression". Significantly increased tracer uptake was found at SPM within some bilateral frontal regions (Brodmann areas 8, 9, 10, 32) in the "Depression + ADHD" subgroup compared to in "Depression". An accuracy of 100% was obtained for the discrimination between the patient groups when thalamic uptake was used in the analysis along with scores from Socialization and Impulsivity scales. CONCLUSION: The findings confirm the previous observation of a cerebellar involvement in ADHD. Higher bilateral frontal 99mTc-HMPAO uptake in "Depression + ADHD" compared to in "Depression" indicate a difference between these subgroups. 99mTc-HMPAO uptake mechanisms are discussed.

Regional lung blood flow and ventilation in upright humans studied with quantitative SPECT.

We used quantitative Single Photon Emission Computed Tomography (SPECT) to study the effect of the upright posture on regional lung blood flow and ventilation. Nine (upright) plus seven (prone and supine) healthy volunteers were studied awake, breathing spontaneously. Regional blood flow and ventilation were marked in sitting upright, supine and prone postures using (113m)In-labeled macroaggregates and inhaled Technegas ((99m)Tc); both remain fixed in the lung after administration. All images were obtained while supine. In comparison with horizontal postures, both blood flow and ventilation were greater in caudal regions when upright. The redistribution was greater for blood flow than for ventilation, resulting in decreasing ventilation-to-perfusion ratios down the lung when upright. We conclude that gravity redistributes regional blood flow and ventilation in the upright posture, while the influence is much less in the supine and prone postures.

Preoperative 99Tc(m)-sestamibi scintigraphy with SPECT localizes most pathologic parathyroid glands.

BACKGROUND AND AIMS: Surgery is the only curative treatment for primary hyperparathyroidism. Focused surgical techniques are being practiced with increasing frequency. Preoperative imaging, such as scintigraphy, is a prerequisite for focused surgery. There is controversy about which preoperative imaging method should be used. The sensitivity reported for parathyroid scintigraphy varies considerably. This study was designed to determine the accuracy of the preoperative imaging routinely used at our institution. MATERIAL AND METHODS: This retrospective study included consecutive patients who underwent a routine dual-phase sestamibi-SPECT (single photon emission computed tomography) scintigraphy and subsequent operation with follow-up. Scintigraphy results were evaluated by comparing the results to surgical findings and histopathology. RESULTS: Two hundred and sixty-four individuals entered the study. Sensitivity for scintigraphy was 84%, specificity 91%, positive predictive value 91%, and negative predictive value 84%. CONCLUSIONS: Sestamibi-SPECT scintigraphy is a sensitive preoperative modality with high positive predictive value. Scintigraphy is a good indicator for when to perform a focused surgical approach and could often correctly guide the actual operation.

Time-to-time correlation of high-risk atherosclerotic lesions identified with [(18)F]-FDG-PET/CT.

OBJECTIVE: It has been shown that [(18)F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can identify macrophage-rich high-risk atherosclerotic plaques in animal models as well as in patients with atherosclerotic plaques in the carotid arteries. The development of inflamed macrophage-rich plaques over time is not well known. This study was performed to determine the variability of such FDG-accumulating plaques between consecutive PET/CT examinations. METHODS: Twenty-eight patients who underwent two whole-body FDG-PET/CT examinations within 7 months for malignant diseases were re-evaluated for atherosclerotic lesions in major arterial segments. The plaques were identified as active, inactive, or mixed depending on their appearance on PET and CT. Every identified plaque was compared with that of the other examination to evaluate the time-to-time correlation. RESULTS: The time-to-time correlation was close to 100% for calcified inactive plaques and about 50% for FDG-accumulating active plaques, with a high consistency between all examined arterial segments in this material. CONCLUSIONS: A large proportion of FDG-accumulating plaques can be identified on consecutive FDG-PET/CT examinations within 7 months.

High 18F-FDG Uptake in synthetic aortic vascular grafts on PET/CT in symptomatic and asymptomatic patients.

UNLABELLED: Graft infection is a serious complication to vascular surgery. The aim of this study was to assess (18)F-FDG uptake in vascular grafts in patients with or without symptoms of graft infection. METHODS: In all 2,045 patients examined by PET/CT at our clinic, 16 patients with synthetic aortic grafts were identified and reevaluated for (18)F-FDG accumulation. Clinical and biochemical data were obtained from patient records. RESULTS: High (18)F-FDG uptake was found in 10 of 12 grafts in the patients who underwent open surgery and in 1 of 4 grafts in patients who underwent endovascular aneurysm repair. On the basis of biochemical and clinical data, it was concluded that 1 of the 16 patients had a graft infection at the time of investigation. CONCLUSION: (18)F-FDG uptake in vascular grafts was found in the vast majority of patients without graft infection. The risk of a false-positive diagnosis of graft infection by (18)F-FDG PET/CT is evident.

Short-time ingestion of colas influences the activity distribution at bone scintigraphy: experimental studies in the mouse.

BACKGROUND: A negative effect of soft drinks, especially phosphate containing colas, on bone mineral contents has been reported. Most studies have been epidemiological investigations or performed in healthy humans. OBJECTIVE: The aim was to study the effect of short-time ingestion of Coca-Cola, a phosphate containing soft drink, and of Fanta, a non-phosphate containing soft drink, in a murine system for bone scintigraphy. This technique may be used to study bone metabolism. DESIGN AND METHODS: After feeding the beverages to the mice during different time periods (2 h to 6 days), the animals were injected with the bone-seeking radiopharmaceutical. The activity distribution was thereafter mapped by dissecting the hind legs and different soft tissue organs and assessing their activity with a gamma-counter. Controls were mice drinking water. RESULTS: After drinking Coca-Cola there was a significantly increased bone uptake of the tracer and a reduced uptake by most soft tissues versus controls. After Fanta there were no differences. Comparing Coca-Cola and Fanta, there was a significantly lower uptake by all soft tissues after Coca-Cola, but no significant difference for bone. CONCLUSIONS: Short-time ingestion of Coca-Cola in mice causes an increased bone uptake and a reduced soft tissue uptake at bone scintigraphy. There may be a similar, weaker effect by Fanta. This is in agreement with previous studies indicating that soft drinks may, on their own, have a metabolic effect on the bone.

Radiologic measurements of tumor response to treatment: practical approaches and limitations.

Objective response assessment is important to describe the treatment effect of anticancer drugs. Standardization by using a "common language" is also important for comparison of results from different trials. In contrast to clinical results, which can be subjective, diagnostic imaging provides a greater opportunity for objectivity and standardization. It was generally accepted that a decrease in tumor size correlated with treatment effect; as a result, imaging was adopted for lesion measurement in the World Health Organization (WHO) criteria in 1979. However, because of some limitations of the WHO criteria, the Response Evaluation Criteria in Solid Tumors (RECIST) were introduced in 2000. In RECIST, imaging was recognized as indispensable for response evaluation of solid tumors. Nevertheless, the widespread use of multidetector computed tomography and other imaging innovations have made RECIST outdated, with a concomitant need for modifications. Meanwhile, newer anticancer agents with targeted mechanisms of action have demonstrated an inherent limitation and unsuitability of anatomic tumor evaluation that assesses only lesion size. In addition, the effect of these new drugs changes the paradigm according to which tumor response or response rate is measured. Complete and partial responses cannot be the end points in all clinical trials; in some cases, disease control or progression-free survival may be the more relevant end point.