Cancer stem cells and the impact of Chinese herbs, isolates and other complementary medical botanicals: a review.

To elucidate the connection between the origin of certain cancers and stem cells, cancer stem cells, the stem cell niche and the tumor microenvironment, and to examine the ability of traditional Chinese herbal medicines and isolates in treating these types of cancers, the existing literature was examined and eight studies regarding Chinese herbal medicines and the prevention of cancer recurrence were critically analyzed and evaluated. Tumor stem cells may be the final target of traditional Chinese medicine. Soy flavones, ginsenoside Rg3, parthenolide, berbamine and curcumin are several examples of Chinese herbal medicines, which have been shown to be effective in the treatment of cancer, and seem to act by targeting cancer stem cells and associated pathways resulting in tumorigenesis. The treatment approaches combined with an overall treatment protocol for the tumor microenvironment and chronic systemic inflammation are likely to provide a more successful outcome than a single tactical approach. As shown in numerous studies in the literature, using complementary disciplines with orthodox treatments may enhance treatment outcomes.

Thermal control of brown adipose tissue in 18F-FDG PET.

UNLABELLED: The visualization of hypermetabolic brown adipose tissue (BAT) on (18)F FDG PET lowers the efficacy of PET and has been linked with the environmental temperature of the patient before presentation. The objective of this paper is to investigate the effectiveness of thermal control on BAT and (18)F-FDG PET. METHODS: Three hundred patients undergoing (18)F-FDG PET were defined by 1 of 2 groups. Group A consisted of 150 consecutive patients from August to October 2009 (spring). Group B consisted of 150 consecutive patients from December to February 2010 (summer). In addition to normal preparation, group B received instructions to dress warmly and was warmed during the uptake period of their scan. Images were assessed for the presence of BAT. Standardized uptake value data were collected and compared. RESULTS: BAT was present in 9.3% of patients; 15.3% of patients that were not warmed (group A) demonstrated BAT, and this was reduced to 3.3% in the group that underwent warming (group B) (P = 0.0005). BAT was more common in men (10.9%) than women (6.8%), and women responded better to warming. Younger patients were more likely to demonstrate BAT (P < 0.001). No significant relationship between BAT and height, weight, or body mass index was found. The most common site for BAT visualization was the cervical region (89%), followed by supraclavicular (75%), paravertebral (50%), suprarenal (21%) and paraaortic (7%) regions. CONCLUSION: Thermal control for the reduction of BAT can achieve reductions in the incidence of BAT by as much as 78%. The reduction of BAT on PET images can reduce false-positive and false-negative results and minimize the need for rescanning.

Risk stratification in heart failure using ¹²³I-MIBG.

Heart failure is a progressive, heterogeneous form of cardiovascular disease that requires treatment to be individualized depending on the presenting symptoms. A decision to use an implantable cardioverter-defibrillator (ICD) is based on chronic heart failure patients presenting with a New York Heart Association classification of II or III and a left ventricular ejection fraction (LVEF) less than or equal to 30%-35%. A large percentage of ICD devices, however, never deliver therapy during their lifetime, and as many as 33% of patients ineligible for an ICD (LVEF > 35%) die of sudden cardiac death. (123)I-metaiodobenzylguanidine ((123)I-MIBG) scintigraphy identifies sympathetic nervous system dysfunction and has been shown to lead to better patient stratification. This article reviews the role of planar (123)I-MIBG global quantitation in improving differentiation of heart failure, regardless of the LVEF, to better identify those in whom an ICD is more likely to reap benefits. It goes on to explore the potential incremental benefit of SPECT-based regional quantitation to risk stratification and provides a case example in which (123)I-MIBG SPECT was used to inform a decision to not use an ICD in a patient eligible under the standard criteria.

Pharmacokinetic considerations for digoxin in older people.

OBJECTIVE: This review aims to arm readers with a deep understanding of pharmacokinetics of digoxin. DATA SOURCES: Pharmacology and pharmacokinetic references texts, and peer reviewed medical journal manuscripts indexed on Medline included based on currency, accuracy and appropriateness. RESULTS: Physiologic changes and disease associated with aging have an impact on pharmacokinetics and pharmacodynamics of medications. Altered drug response and increased adverse reactions are common amongst the elderly. The narrow therapeutic index of digoxin and pharmacokinetic changes associated with aging increases the risk of toxicity. In the aging population, a number of factors combine to increase the risk, severity and likelihood of hospitalisation or death due to adverse drug effects: changes to absorption, distribution, metabolism and excretion,increased susceptibility to drug sensitivity,co-existing pathology,polypharmacy. CONCLUSION: A thorough understanding of digoxin pharmacokinetics in the older person is essential for improved therapeutic outcomes, improved compliance, reduced morbidity and improved quality of life.

The incremental value of SPECT/CT in characterizing solitary spine lesions.

UNLABELLED: The purpose of this study was to investigate the incremental value and diagnostic impact of SPECT/CT in patients who had a solitary spinal lesion on a bone scan. METHODS: A prospective study was performed on 80 patients (50 with known cancer) who underwent (99m)Tc-methylene diphosphonate whole-body planar bone scintigraphy and had a solitary spinal lesion. These lesions were then further evaluated using SPECT/CT. RESULTS: Lesions were localized to the vertebral body in 38 patients (47.5%), pedicle in 15 (18.8%), facet joint in 15 (18.8%), transverse process in 2 (2.5%), spinous process in 2 (2.5%), lamina in 3 (3.8%), and end plates in 5 (6.2%). Although the specificity of planar bone scans was excellent (100%), sensitivity was only 6.1% but increased to 78.8% after the addition of SPECT/CT. The results provide evidence of a substantial incremental increase in diagnostic accuracy using SPECT/CT over planar imaging alone for patients in whom a solitary spinal lesion is noted. CONCLUSION: The addition of SPECT/CT significantly reduced the number of false-negative results and increased the number of true-positive results. SPECT/CT also reduced the number of equivocal reports. A definitive diagnosis was given for most patients, indicating improved diagnostic confidence with the addition of SPECT/CT, compared with planar imaging alone, in patients with solitary spinal lesions.

Integrative oncology in Australia.

The use of alternative medicine (AM) in Australia dates back to its earliest times, with the indigenous medicine of the aboriginal peoples and the folk medicine of the early English settlers. AM has until recently existed quite separately from Western biomedicine (WB) and there has been little integration of the two systems. Now, referred to as complementary medicine (CM), there has been a movement over the last 20 years to include CM in WB mainstream practices. Varying degrees of success have been reported but for the discipline of oncology. Medical oncology (MO) in Australia is demanding CM provide high levels of evidence for any inclusion in cancer protocols. There are just now the beginnings of this integration, particularly as CM is now being taught in the public university system to a PhD level as well as the public demand for their medical doctors to communicate with their CM practitioners. MO specialists are now open to a dialogue with their CM counterparts.

Pharmacology in nuclear cardiology.

Although exercise remains the preferred method of cardiac stress testing, pharmacological stress plays an important role in nuclear cardiology. The globally ageing population will see an expansion of the application of pharmacological stress testing, and with this, comes the need to understand the pharmacological basis, mechanisms of action, potential interactions and adverse effects to inform usage in less-than-ideal circumstances. This study aims to enhance the decision-making process in day-to-day clinical nuclear cardiology practice through a better understanding of nuances relevant to the pharmacological agents used for cardiac stress testing.

Scintigraphic evaluation of acute lower gastrointestinal hemorrhage: current status and future directions.

This review examines the role and limitations of scintigraphic evaluation in acute lower gastrointestinal hemorrhage. A detailed discussion of methods for improving diagnostic outcomes is provided. Techniques and recommendations are offered for optimization of red blood cell scintigraphy for earlier detection and more accurate localization of acute lower gastrointestinal hemorrhage.

Clinical Utility of Out-of-Hours Chest Radiographs.

PURPOSE: In Australia, radiology services are provided as full 24-hour services, 24-hour urgent out-of-hours (on-call) services, and business hours-only service. The primary purpose of this study was to determine whether out-of-hours (11 PM-7 AM) chest x-ray (CXR) referrals are consistent with out-of-hours service expectations associated with the cost and inconvenience of calling staff in from home. A secondary objective was to determine whether the mobile chest plain film examinations are consistent with expectations of a patient's increased degree of infirmary. METHOD: A retrospective analysis was undertaken over 6 contiguous months for patients referred from the emergency department for CXRs out-of-hours and within standard hours (in-hours). The study population included 436 out-of-hours patients recruited into the investigation cohort and a matched cohort of 438 CXR examinations performed in-hours. The key information gleaned from the study was concordance or discordance between the clinical details relating to the actual referral and the findings of the CXR. RESULTS: The total sample comprised 414 females (47.4%) and 460 males (52.6%). The mean age was 55.3 years, median was 56.5 years, with a range of 0-97 years. The examination type performed was 8.9% mobile compared with 91.1% departmental for the sample. It was found that there was 43.5% prevalence of abnormalities, 27.0% significant abnormalities, and 8.7% clinically significant abnormality. The predictors found for clinically significant abnormalities were increasing patient age (P < .001) and the need for mobile examination (P < .001). Performing the examination out-of-hours did not predict a clinically significant abnormality (P = .491) and similarly, gender did not predict clinically significant abnormality (P = .152). CONCLUSION: The results suggest that similar approaches to referrals for CXRs are applied in-hours and during the out-of-hours period which are inconsistent with the "urgent" philosophy that should accompany an out-of-hours service. Only increasing patient age and the need for a mobile CXR offered predictors of a clinical significant abnormality and this offers an insight into the potential approach to the development of referral guidelines for out-of-hours procedures.

Inflammation and cancer: tumor initiation, progression and metastasis, and Chinese botanical medicines.

Both historically and contemporarily, cancer is seen as an inflammatory process. Evidence has emerged in the last two decades that at the molecular level most chronic diseases, including cancer, are caused by a dysregulated inflammatory response. The identification of transcription factors such as nuclear factor-kappa B and signal transducer and activator of transcription 3 and their gene products such as tumor necrosis factor, interleukin-1, interleukin-6, chemokines, cyclooxygenase-2, and vascular endothelial growth factor, adhesion molecules and others has provided the molecular basis for the role of inflammation in cancer. Tumor initiation, its progression and metastasis and the failure of immune suppression of tumors all can be attributed in part to chronic and systemic inflammation. Chinese herbs have a long history in both treatment of cancer and suppression of inflammation. This paper looks at recent research on cancer and inflammation and Chinese herbs and compounds, which can be used in the treatment of cancer.

A role for subtraction scintigraphy in the evaluation of lower gastrointestinal bleeding in the athlete.

While lower gastrointestinal haemorrhage (LGIH) in the athlete tends to be self-limiting in the majority of athletes, recurrent symptoms occur in some athletes. It is important to identify the smaller percentage of athletes in whom risks and recurrence are greater because both their general health and athletic performance might benefit from more rigorous clinical evaluation. Technetium-99m red blood cell ((99m)Tc RBC) scintigraphy is a technique for detection and localisation of LGIH and offers a number of significant advantages over other imaging modalities in the evaluation of LGIH. Nonetheless, there are a number of limitations recognised in (99m)Tc RBC scintigraphic evaluation of LGIH. Subtraction scintigraphy in (99m)Tc RBC evaluation of gastrointestinal haemorrhage may offer a tool to overcome limitations of conventional scintigraphy. In essence, subtracting a nominal 'mask' or reference image from all subsequent images provides a mechanism to view only the information contributed by accumulated bleeding, removing potential sources of both false-positive and false-negative findings. While the limitations of procedures available for the evaluation of LGIH are generally prohibitive of effective application in the obscure bleeding associated with athletic performance, adopting subtraction methods in conjunction with conventional (99m)Tc RBC scintigraphy may offer a valuable tool in identification and localisation of bleeding sites. The general health and athletic performance may be enhanced in some athletes when the underlying cause of bleeding can be more appropriately managed.

Impact factors in nuclear medicine journals.

The annual Journal Citation Reports includes several statistics and figures, the key figure being journal impact factor. Journal impact factor, despite being widely used, is not well understood. This article aims to provide a broader understanding of impact factors and the implications thereof.

Improved detection and localization of lower gastrointestinal hemorrhage using subtraction scintigraphy: clinical evaluation.

UNLABELLED: Does subtraction scintigraphy improve the diagnostic utility of scintigraphic evaluation in acute lower gastrointestinal hemorrhage? METHODS: This research was a retrospective clinical study using a repeat-measures design of randomized control and experimental groups. A single patient dataset provided both the control group (conventional scintigraphy) and the experimental group (conventional and subtraction techniques). Forty-nine raw (99m)Tc-red blood cell studies were randomized and interpreted by 4 independent physicians as conventional scintigraphy data only (round 1). The conventional scintigraphy studies were combined with subtraction images and randomized for reinterpretation (round 2). RESULTS: Although there was a decrease in the mean, no statistically significant difference was noted between the mean time to bleed detection between interpretive rounds 1 and 2 (P = 0.524). The addition of subtraction scintigraphy to the interpretation process changed the outcome from "probably present" to "absent" for 14% of patients and from "equivocal" to "absent" for another 12%, and this change had a marked effect on the false-positive rate. The false-positive rate decreased from 9.6% in round 1 to 3.6% in round 2. Receiver operator characteristic analysis showed that combining conventional scintigraphy with subtraction scintigraphy improved test performance. CONCLUSION: False-positive studies can be reduced by using subtraction scintigraphy in conjunction with conventional scintigraphy in the interpretive process.

Improved detection and localization of lower gastrointestinal tract hemorrhage by subtraction scintigraphy: phantom analysis.

UNLABELLED: Acute lower gastrointestinal tract hemorrhage (LGIH) has significant morbidity and mortality outcomes. Although several causes of LGIH can be life threatening, most can be effectively treated; therefore, early detection and accurate localization of bleeding sites are critical for successful patient management. METHODS: This study was a phantom experimental study with a repeated-measures design. The minimum detectable bleeding rate, the minimum detectable bleed volume, the sensitivity for detection, and the time required for detection were determined and compared for conventional scintigraphy (CS) and 3 experimental techniques: reference subtraction scintigraphy (RSS), sequential subtraction scintigraphy (SSS), and alternate sequential subtraction scintigraphy (ASSS). RESULTS: The minimum detectable bleeding rates within the first hour were 0.05 mL.min-1 for CS and RSS, 0.1 mL.min-1 for ASSS, and 0.5 mL.min-1 for SSS. This study demonstrated minimum detectable bleed volumes of 2.2 mL for CS, 2.3 mL for RSS, 5 mL for ASSS, and 5 mL for SSS stratified to a "definitely present" certainty. No statistically significant difference was noted in the mean time to detection between CS and the subtraction techniques. Receiver-operating-characteristic analysis indicated that combining CS and RSS improved test performance and increased overall sensitivity to 75% from 68.3% for CS and 71.7% for RSS. CONCLUSION: Supplementing conventional datasets with RSS and ASSS may provide a useful tool that combines the advantages offered for lesion detectability by a high-contrast 99mTc-sulfur colloid study with the window of opportunity offered by 99mTc-labeled red blood cell scanning.

QGS ejection fraction reproducibility in gated SPECT comparing pre-filtered and post-filtered reconstruction.

INTRODUCTION: The aim of this investigation was to compare the QGS determined functional parameters using pre-filtering to that using post-filtering in the gated myocardial perfusion single photon emission computed tomography (SPECT) reconstruction process. METHODOLOGY: A total of 25 patient files were examined, each with both a gated rest and gated stress study, and were reconstructed using two strategies. The first employed pre-filtering with a Butterworth low pass filter (order 4.0 and cut-off 0.21) and the second employed post-filtering with a Butterworth low pass filter (order 5.0 and cut-off 0.21). Following reconstruction and reorientation, gated short axis slices were evaluated with QGS software. RESULTS: The mean ejection fraction for the post-filtered data was 49.5% (95% CI, 45.8-53.1%) and for the pre-filtered data was 54.8% (95% CI, 51.4-58.1%). Excellent correlation was demonstrated between the pre- and post-filtered ejection fractions with a correlation coefficient of 0.964. The mean difference between matched pairs of pre- and post-filtered ejection fraction data was 5.3% (95% CI, 4.3-6.3%). The match pair t-test demonstrated a statistically significant difference between matched pairs (P<0.0001) and a statistically significant difference was shown between the means (P=0.005). CONCLUSION: The impact of performing pre-filtering on data in the reconstruction process is significant with a 5.3% increase in the calculated ejection fraction over post-filtering. Clearly, this has the potential to undermine diagnostic and prognostic roles of functional parameters.

Rest versus stress ejection fraction on gated myocardial perfusion SPECT.

OBJECTIVES: It is widely accepted that exercise-induced stunning has an impact on left ventricular ejection fraction (EF); yet, despite the recommendations of the American Society of Nuclear Cardiology, many departments only perform gated SPECT on stress studies. The aim of this investigation was to determine the relationship between rest EF and stress EF in myocardial perfusion studies and to identify possible predictors of variability. METHODS: This study was a retrospective cross-sectional study of 133 patients (266 studies) undergoing myocardial perfusion SPECT. Automated computer-generated functional data (end-diastolic volume, end-systolic volume [ESV], and EF) for rest and stress studies were correlated as matched pairs and analyzed with respect to the following variables: age, sex, stress method, time between stress and scanning, and presence or absence of pathology scintigraphically. Differences in matched EF pairs (DeltaEF) and transient dilatation were also determined. RESULTS: Matched pairs of rest EF and stress EF demonstrated excellent correlation (0.90) with no significant difference noted (P=0.15). Bland-Altman analysis demonstrated a mean DeltaEF of -0.65% (95% confidence interval [CI], -1.54% to 0.23%) with 94% of data points within the 95% limits of agreement. No statistically significant difference was determined between the mean DeltaEF and the hypothetic mean of 0 (P=0.15). A time between stress and scanning of <45 min was shown to be predictive of a negative DeltaEF (P=0.04). Transient dilatation was shown to be predictive of a negative DeltaEF (P=0.01). Resting ESVs between 25 and 50 mL were shown to be predictive of a negative DeltaEF (P=0.02). A stress EF of <50% was also shown to be predictive of a negative DeltaEF (P=0.003). CONCLUSION: No statistically significant difference between stress and rest EF was demonstrated and no trend was identified toward either under- or overestimation of the stress EF with a DeltaEF. A negative DeltaEF was, however, predicted by transient dilatation of >1.0, a time between stress and scanning of <45 min, a stress EF of <50, and an ESV between 25 and 50 mL. Gated SPECT performed on both stress and rest studies may provide a mechanism to predict exercise-induced stunning and transient dilatation.