Tetracycline-levofloxacin versus amoxicillin-levofloxacin quadruple therapies in the second-line treatment of Helicobacter pylori infection.

BACKGROUND: The Maastricht V/Florence Consensus Report recommends amoxicillin-fluoroquinolone triple or quadruple therapy as a second-line treatment for Helicobacter pylori infection. An important caveat of amoxicillin-fluoroquinolone rescue therapy is poor eradication efficacy in the presence of fluoroquinolone resistance. The study aimed to investigate the efficacies of tetracycline-levofloxacin (TL) quadruple therapy and amoxicillin-levofloxacin (AL) quadruple therapy in the second-line treatment of H. pylori infection. METHODS: Consecutive H. pylori-infected subjects after the failure of first-line therapies were randomly allocated to receive either TL quadruple therapy (tetracycline 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) or AL quadruple therapy (amoxicillin 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) for 10 days. Post-treatment H. pylori status was assessed 6 weeks after the end of therapy. RESULTS: The study was early terminated after an interim analysis. In the TL quadruple group, 50 out of 56 patients (89.3%) had successful eradication of H. pylori infection. Cure of H. pylori infection was achieved only in 39 of 52 patients (69.6%) receiving AL quadruple therapy. Intention-to-treat analysis showed that TL quadruple therapy achieved a markedly higher eradication rate than AL quadruple therapy (95% confidence interval: 4.8% to 34.6%; p = 0.010). Further analysis revealed that TL quadruple therapy had a high eradication rate for both levofloxacin-susceptible and resistant strains (100% and 88.9%). In contrast, AL quadruple therapy yielded a high eradication for levofloxacin-susceptible strains (90.9%) but a poor eradication efficacy for levofloxacin-resistant strains (50.0%). The two therapies exhibited comparable frequencies of adverse events (37.5% vs 21.4%) and drug adherence (98.2% vs 94.6%). CONCLUSIONS: Ten-day TL quadruple therapy is more effective than AL quadruple therapy in the second-line treatment of H. pylori infection in a population with high levofloxacin resistance.

Correlation of 18F-FDG uptake and thyroid cancer stem cells.

BACKGROUND: 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (18F-FDG PET) has the potential to detect various types of cancers, including thyroid cancer (TC), at a potentially curable stage. Increased uptake of 18F-FDG was observed in anaplastic and poorly differentiated thyroid cancer cells, and PET-positive tumors are more likely to be resistant to 131I treatment. As cancer stem cells (CSCs) possess a dedifferentiated phenotype and are resistant to many anticancer therapies, we hypothesized that the expression of CSC-related markers is correlated with the ability of tumor cells in TC to uptake FDG. METHODS: The present study cohort included 12 patients with TC, who underwent 18F-FDG PET/CT imaging before surgery. Quantitative polymerase chain reaction (QPCR) and immunohistochemical (IHC) staining were performed to analyze the expression patterns of gene markers related to embryonic stem (ES) cells and CSCs in TC. RESULTS: The mRNA expression levels of CSC- (CD133 and CD44) and ES-related genes (Oct4 and Nanog) were higher in TC tissue than in normal thyroid tissue, whereas the mRNA expression levels of thyroid-specific genes (Tg, TSHR, and TTF1) were higher in normal thyroid tissue than in TC tissue. There was a positive and statistically significant correlation between FDG uptake (SUVmax) of tumor and relative mRNA levels of CD133, CD44, Oct4, and Nanog. The IHC results demonstrated that CD133 and Nanog were expressed in TC tissue but not in normal thyroid tissue, however, CD44 expression was observed in both TC and normal thyroid tissue. Comparisons of the clinicopathological parameters between TC tissues with low and high SUVmax demonstrated significant differences in protein level of CD133 but not in that of Nanog. CONCLUSIONS: The pre-therapeutic tumor SUVmax obtained from 18F-FDG PET/CT may be a potential predictor for evaluating the proportion of CSC population in individual patients with TC.

Equivalent efficacies of reverse hybrid and concomitant therapies in first-line treatment of Helicobacter pylori infection.

BACKGROUND AND AIM: Concomitant therapy is a recommended first-line treatment for Helicobacter pylori infection in most national or international consensuses. Reverse hybrid therapy is a modified 14-day concomitant therapy without clarithromycin and metronidazole in the final 7 days. This study aims to test whether 14-day reverse hybrid therapy is non-inferior to 14-day concomitant therapy in the first-line treatment of H. pylori infection. METHODS: Helicobacter pylori-infected adult patients were randomly assigned to receive either reverse hybrid therapy (dexlansoprazole 60 mg o.d. plus amoxicillin 1 g b.d. for 14 days, and clarithromycin 500 mg plus metronidazole 500 mg b.d. for initial 7 days) or concomitant therapy (dexlansoprazole 60 mg once o.d. plus amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg b.d. for 14 days). H. pylori status was assessed 6 weeks after the end of treatment. RESULTS: Helicobacter pylori-infected participants (n = 248) were randomized to receive either 14-day reverse hybrid therapy (n = 124) or 14-day concomitant therapy (n = 124). Intention-to-treat analysis demonstrated that the two therapies had comparable eradication rate (95.2% vs 93.5%; 95% confidence interval, -4.0% to 7.4%; P = 0.582). However, reverse hybrid therapy had a much lower frequency of adverse events than concomitant therapy (20.2% vs 38.7%, P = 0.001). The two therapies exhibited comparable drug adherence (93.5% vs 87.9%, P = 0.125). CONCLUSIONS: Fourteen-day reverse hybrid therapy and 14-day concomitant therapy are equivalent in efficacy for the first-line treatment of H. pylori infection. However, reverse hybrid therapy has fewer adverse events compared with concomitant therapy.

Short-term and long-term impacts of Helicobacter pylori eradication with reverse hybrid therapy on the gut microbiota.

BACKGROUND AND AIMS: Anti-Helicobacter pylori therapy may lead to the growth of pathogenic or antibiotic-resistant bacteria in the gut. The study aimed to investigate the short-term and long-term impacts of H. pylori eradication with reverse hybrid therapy on the components and macrolide resistance of the gut microbiota. METHODS: Helicobacter pylori-related gastritis patients were administered a 14-day reverse hybrid therapy. Fecal samples were collected before treatment and at the end of week 2, week 8, and week 48. The V3-V4 region of the bacterial 16S rRNA gene in fecal specimens was amplified by polymerase chain reaction and sequenced on Illumina MiSeq platform. Additionally, amplification of erm(B) gene (encoding erythromycin resistance methylase) was performed. RESULTS: Reverse hybrid therapy resulted in decreased relative abundances of Firmicutes (from 62.0% to 30.7%; P < 0.001) and Actinobacteria (from 3.4% to 0.6%; 0.032) at the end of therapy. In contrast, the relative abundance of Proteobacteria increased from 10.2% to 49.1% (0.002). These microbiota alterations did not persist but returned to the initial levels at week 8 and week 48. The amount of erm(B) gene in fecal specimens was comparable with the pretreatment level at week 2 but increased at week 8 (0.025) and then returned to the pretreatment level by week 48. CONCLUSIONS: Helicobacter pylori eradication with reverse hybrid therapy can lead to short-term gut dysbiosis. The amount of erm(B) gene in the stool increased transiently after treatment and returned to the pretreatment level at 1-year post-treatment.

Equivalent Efficacies of Reverse Hybrid and Bismuth Quadruple Therapies in Eradication of Helicobacter pylori Infection in a Randomized Controlled Trial.

BACKGROUND & AIMS: Bismuth quadruple therapy is recommended as a first-line treatment for Helicobacter pylori infection in the United States but hybrid therapy is an alternative option. Reverse hybrid therapy (proton pump inhibitor plus amoxicillin for 14 days, and clarithromycin plus metronidazole for the initial 7 days) is a simplified hybrid treatment. We aimed to assess the efficacies of reverse hybrid therapy vs bismuth quadruple therapy as first-line treatments for patients with H pylori infection in a randomized trial. METHODS: In a prospective study, patients with H pylori infection were randomly assigned to groups that received either reverse hybrid therapy (n = 176) or a bismuth quadruple therapy (pantoprazole, bismuth, tetracycline, and metronidazole for 14 days; n = 176). Patients were examined the end of therapy for adverse events. The study was performed from August 2015 through February 2017. The primary outcome was cure of H pylori infection, determined based on a negative result from the urea breath test, or negative results from histologic analysis, the urease test, and bacterial culture analyses. RESULTS: H pylori infection was eradicated from 96.6% of patients who received reverse hybrid therapy and 96.0% who received bismuth quadruple therapy-this difference was not significant in the intention-to-treat analysis (95% CI, 8.0% ∼ 2.2%; P = .281). There were no significant differences between therapies eradication of clarithromycin-resistant strains (88.2% with reverse hybrid therapy vs 92.3% with bismuth quadruple therapy) or metronidazole-resistant strains (100% vs 96.9%). However, reverse hybrid therapy was associated with fewer adverse events (18.7% of patients) than bismuth quadruple therapy (47.7%) (P < .001). CONCLUSIONS: In a randomized trial, we found 14-day reverse hybrid therapy to not be inferior to bismuth quadruple therapy as a first-line treatment for H pylori infection. Reverse hybrid therapy was associated with fewer adverse events. ClincialTrials.gov no: NCT02547038.

Which nasopharyngeal cancer patients need adaptive radiotherapy?

BACKGROUND: Adaptive radiotherapy (ART) has potential benefits in patients with nasopharyngeal cancer (NPC). This retrospective study aimed to identify the factors favoring ART. MATERIALS AND METHODS: Forty NPC patients were retrospectively included in this study. All patients received two-phase, volumetric modulated arc radiotherapy (VMAT) and underwent a second computed tomography (CT) for the phase II ART. We generated phantom, non-ART plans by a hybrid method for comparison with ART plans. A paired t-test was used to evaluate the dose differences between these two plans. A subgroup analysis through a paired t-test was used to evaluate the factors favoring ART. RESULTS: The second CT images were captured at the median 22 fractions. The median total dose of the planning target volume-one (PTV-1) was 72 Gy, and the phase II dose was 16 Gy. The volumes of the ipsilateral parotid gland (23.2 vs. 19.2 ml, p <  0.000), contralateral parotid gland (23.0 vs. 18.4 ml, p <  0.000), clinical target volume-1 (CTV-1, 32.2 vs. 20.9 ml, p <  0.000), and PTV-1 (125.8 vs. 107.3 ml, p <  0.000) all shrunk significantly between these two CT simulation procedures. Among the nearby critical organs, only the ipsilateral parotid gland displayed significant dose reduction by the ART plan (5.3 vs. 6.0 Gy, p = 0.004). Compared to the phantom plan, the ART could significantly improve the PTV-1 target volume coverage of D98 (15.4 vs. 12.3 Gy, p < 0.000). Based on the D98 of PTV-1, the factors of a large initial weight (> 60 kg, p < 0.000), large body mass index (BMI) (> 21.5, p < 0.000), obvious weight loss (> 2.8 kg, p < 0.000), concurrent chemoradiotherapy (p < 0.000), and stages III-IV (p < 0.000) favored the use of ART. CONCLUSIONS: ART could significantly reduce the mean dose to the ipsilateral parotid gland. ART has dosimetrical benefit for patients with a heavy initial weight, large BMI, obvious weight loss, concurrent chemoradiotherapy, and cancer in stages III-IV.

Helicobacter pylori eradication with bismuth quadruple therapy leads to dysbiosis of gut microbiota with an increased relative abundance of Proteobacteria and decreased relative abundances of Bacteroidetes and Actinobacteria.

BACKGROUND: Bismuth quadruple therapy is the treatment of choice for the first-line therapy of Helicobacter pylori infection in areas of high clarithromycin resistance. Currently, the impact of the promising treatment on gut microbiota remains unclear. AIM: To investigate the short-term and long-term impacts of bismuth quadruple therapy on gut microbiota. METHODS: Adult patients with H. pylori-related gastritis were treated with 14-day bismuth quadruple therapy. Fecal samples were collected before treatment at week 2, week 8, and week 48. Nucleic acid extraction from fecal samples was performed. The V3-V4 region of the bacterial 16S rRNA gene was amplified by polymerase chain reaction and sequenced with the MiSeq followed by data analysis using Qiime pipeline. RESULTS: Eleven patients received complete follow-up. Before treatment, the most abundant phyla were Firmicutes (45.3%), Bacteroidetes (24.3%), Proteobacteria (9.9%), and Actinobacteria (5.0%). At the end of bismuth therapy, the relative abundances of Bacteroidetes and Actinobacteria decreased to 0.5% (P < .001) and 1.3% (P = .038), respectively. Additionally, the relative abundance of Verrucomicrobia also decreased from 3.2% to 1.11E-3% (P = .034). In contrast, the relative abundances of Proteobacteria and Cyanobacteria increased (P < .001 and P = .003, respectively). At week 8, the relative abundances of all phyla restored to the levels at baseline. The relative abundances of all phyla at week 48 also did not significantly differ from those at baseline. During eradication therapy, 6 patients (55%) reported at least 1 adverse event. The relative abundance of phylum Proteobacteria in patients with adverse effects was more than that in patients without adverse effects (68.7% ± 8.8% vs 43.4% ± 25.5%; P = .048). CONCLUSIONS: Bismuth quadruple therapy for H. pylori eradication can lead to short-term dysbiosis of gut microbiota. The increase in Proteobacteria in gut microbiota may attribute to the development of adverse effects during bismuth quadruple therapy.

Ten-Day Quadruple Therapy Comprising Proton Pump Inhibitor, Bismuth, Tetracycline, and Levofloxacin is More Effective than Standard Levofloxacin Triple Therapy in the Second-Line Treatment of Helicobacter pylori Infection: A Randomized Controlled Trial.

OBJECTIVES: Proton pump inhibitor (PPI)-amoxicillin-fluoroquinolone triple therapy is recommended as a second-line treatment of Helicobacter pylori infection in the Maastricht V/Florence Consensus Report. However, the eradication rate of this standard salvage treatment is suboptimal. The objective of this study is to compare the efficacy of esomeprazole-bismuth-tetracycline-levofloxacin therapy (TL quadruple therapy) and esomeprazole-amoxicillin-levofloxacin triple therapy (AL triple therapy) in rescue treatment for H. pylori infection. METHODS: Consecutive H. pylori-infected subjects after failure of first-line therapies were randomly allocated to receive either TL quadruple therapy (esomeprazole 40 mg b.d., bismuth 120 mg q.d.s., tetracycline 500 mg q.d.s., and levofloxacin 500 mg o.d.) or AL triple therapy (esomeprazole 40 mg b.d., amoxicillin 500 mg q.d.s., and levofloxacin 500 mg o.d.) for 10 days. H. pylori status was assessed 6 weeks after the end of treatment. RESULTS: The study was stopped after an interim analysis. Of 50 patients in the TL quadruple therapy, 49 (98.0%) had successful eradication of H. pylori infection. Cure of H. pylori infection was achieved in 36 of 52 patients (69.2%) receiving AL triple therapy. Intention-to-treat analysis demonstrated that TL quadruple therapy achieved a markedly higher eradication rate than AL triple therapy (difference: 28.8%; 95% confidence interval: 15.7% to 41.9%; P<0.001). Per-protocol analysis yielded a similar result (97.8% vs. 68.6%; P<0.001). The two treatment groups exhibited comparable frequencies of overall adverse events (22.0% vs. 11.5%) and drug compliance (90.0% vs. 98.1%). The subgroup analysis showed that TL quadruple therapy was superior to AL triple therapy in patients with failure of either standard triple therapy (100% vs. 75.0%; P=0.010) or non-bismuth quadruple therapy (95.0% vs. 52.6%; P=0.003). CONCLUSIONS: Ten-day PPI-bismuth-tetracycline-levofloxacin quadruple therapy is a good option for rescue treatment of H. pylori infection following failure of standard triple or non-bismuth quadruple therapy.

Utility of (18)F-FDG PET/CT in patients with advanced squamous cell carcinoma of the uterine cervix receiving concurrent chemoradiotherapy: a parallel study of a prospective randomized trial.

PURPOSE: The aim of this prospective study was to assess the usefulness of (18)F-FDG PET/CT performed before and during treatment for predicting treatment failure in patients with advanced squamous cell carcinoma of the uterine cervix treated with concurrent chemoradiotherapy (CCRT). METHODS: Patients with cervical squamous cell carcinoma, International Federation of Gynecology and Obstetrics stage III/IVA or positive pelvic or paraaortic lymph node (LN) metastasis without other distant metastasis on PET/CT entering a randomized trial of CCRT (AGOG 09-001) were eligible. PET/CT scans were performed at baseline, during week 3 of CCRT and 2 - 3 months after CCRT. PET/CT parameters were correlated with sites of failure and overall survival (OS). The resulting predictors developed from the study cohort were validated on two independent datasets using area under the curve values, sensitivities and specificities. RESULTS: With a median follow-up of 54 months for survivors, 20 (36 %) of the 55 eligible patients were proven to have treatment failure. Sites of failure were local in five, regional in 11, and distant in 11. Four predictors for local failure, three for regional failure, and four for distant failures were identified. After validation with two independent cohorts of 31 and 105 patients, we consider the following as clinically useful predictors: pretreatment metabolic tumour volume (MTV) and during-treatment cervical tumour MTV for local failure; during-treatment SUVnode (maximum standardized uptake value of LNs) for regional and distant failure, and during-treatment MTV for distant failure. During-treatment SUVnode (P = .001) and cervical tumour MTVratio (P = .004) were independent significant predictors of OS by stepwise Cox regression. CONCLUSION: PET/CT imaging before and during treatment is useful for predicting failure sites and OS, making tailored therapeutic modifications feasible with potential outcome improvement during primary therapy.

Ten-day Quadruple therapy comprising proton-pump inhibitor, bismuth, tetracycline, and levofloxacin achieves a high eradication rate for Helicobacter pylori infection after failure of sequential therapy.

BACKGROUND: Sequential therapy has been recommended in the Maastricht IV/Florence Consensus Report as the first-line treatment for Helicobacter pylori eradication in regions with high clarithromycin resistance. However, it fails in 5-24% of infected subjects, and the recommended levofloxacin-containing triple rescue therapy only achieves a 77% eradication rate after failure of sequential therapy. AIM: To investigate the efficacy of a novel quadruple therapy comprising proton-pump inhibitor, bismuth, tetracycline, and levofloxacin for rescue treatment of sequential therapy. METHODS: This was a multicenter study in which H. pylori-infected patients who had failed sequential therapy received a 10-day quadruple therapy (esomeprazole (40 mg b.d), tripotassium dicitrato bismuthate (120 mg q.d.s.), tetracycline (500 mg q.d.s.), and levofloxacin (500 mg o.d.) for 10 days). H. pylori status was examined 6 weeks after the end of treatment. RESULTS: From July 2007 to June 2012, twenty-four subjects received 10-day quadruple therapy. The eradication rates according to intention-to-treat and per-protocol analyses were both 95.8% (23 of 24; 95% confidence interval, 87.8-103.8%). Adverse events were seen in 25.0% (6 of 24) of the patients. Drug compliance was 100.0% (24/24). CONCLUSIONS: The 10-day quadruple therapy comprising proton-pump inhibitor, bismuth, tetracycline, and levofloxacin achieves a very high eradication rate for H. pylori infection after failure of sequential therapy. It is well tolerated and has great potential to become a good choice of rescue treatment following non-bismuth-containing quadruple therapy in regions with high clarithromycin resistance.

Survival outcomes of radium-223 therapy for metastatic castration-resistant prostate cancer following national health insurance reimbursement in Taiwan.

BACKGROUND: Radium-223 dichloride (Ra-223) prolongs overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC) with symptomatic bone metastases. However, there is considerable variation in outcomes among individuals. We aimed to evaluate the prognostic determinants associated with patient survival following National Health Insurance (NHI) reimbursement for Ra-223 therapy in Taiwan. METHODS: Patients with mCRPC who underwent Ra-223 treatment at Taipei Veterans General Hospital were retrospectively enrolled. Each intravenous Ra-223 dose was administered at 55 kBq/kg at 4-week intervals. Clinical outcomes were obtained from medical records; potential prognostic factors for survival were assessed. Kaplan-Meier analysis was used to generate cumulative survival curves; between-group differences were evaluated using the Chi-squared test. Statistical significance was set at p < 0.05. RESULTS: Seventy-six patients underwent Ra-223 therapy; 62 patients received NHI reimbursement and the remainder self-paid. Fifty patients (65.8%) completed six cycles of treatment; 26 (34.2%) received 1 to 5 cycles. Mortality occurred in 47 patients. Factors significantly associated with survival included ≤five bone metastases ( p = 0.0018), baseline prostate-specific antigen (PSA) ≤36 ng/mL ( p = 0.0004), baseline alkaline phosphate (ALP) <115 U/L ( p = 0.0007), and baseline hemoglobin (Hb) >12 g/dL ( p = 0.0029). Patients who completed six cycles of treatment achieved significantly higher OS compared to those who did not ( p < 0.0001). There has been a 4.4-fold increase in the number of patients since reimbursement began; there was no significant difference in OS between patients who received NHI reimbursement and those who self-paid. CONCLUSION: Administration of Ra-223 demonstrates considerable potential to extend the survival of patients with mCRPC. Survival outcomes may be influenced by various prognostic factors. However, no significant difference in OS was observed subsequent to reimbursement of Ra-223 therapy for mCRPC through the NHI system in Taiwan.

Prognostic assessment of 18F-boronophenylalanine positron emission tomography (BPA-PET) in salvage boron neutron capture therapy for malignant brain tumors.

Background: Boron neutron capture therapy (BNCT) stands out as a propitious anti-cancer modality. 18F-boronophenylalanine positron emission tomography (BPA-PET) holds the potential to ascertain the concentration of BPA within the tumor, enabling meticulous treatment planning and outcome evaluation. However, no studies have been conducted on comparing the outcomes of those treated with BNCT to those who did not undergo this therapy. This study endeavors to analyze the correlation between BPA-PET and BNCT in the context of malignant brain tumors, and assess the survival outcomes following BNCT. Methods: A cohort study was performed on patients who underwent BPA-PET between February 2017 and April 2022 in our hospital. Patients were stratified into two groups: those subjected to BNCT (Group 1) and those not (Group 2). The tumor to normal tissue (T/N) ratio derived from BPA-PET was set at 2.5. The findings were scrutinized based on clinical follow-up. Student's t-test and Chi-squared test were employed to discern differences between the groups. A cumulative survival curve was constructed employing the Kaplan-Meier method. Differences were considered statistically significant at P<0.05. Results: In total, 116 patients with T/N ratios obtained from BPA-PET were enrolled. BNCT was administered to 58 patients, while mortality was observed in 100 patients. The median overall survival (OS) for the two groups was 8.5 and 6.0 months, respectively. The cumulative OS exhibited no significant discrepancy between the two groups, nor in their T/N ratios. Within Group 1, 44 out of 58 (75.9%) patients exhibited T/N ratios exceeding 2.5. Excluding 3 patients who expired within 3 months, 55 out of 58 patients were evaluated for response after BNCT. The objective response rate (ORR) was 30.9%. Patients achieving ORR displayed substantially higher survival rates compared to those without (median OS 13.5 vs. 8.3 months, P=0.0021), particularly when T/N ratio exceeded 2.5 (median OS 14.8 vs. 9.0 months, P=0.0199). Conclusions: BNCT does not appear indispensable for prolonging the survival of patients afflicted with malignant brain tumors. Nevertheless, it proves advantageous when ORR is attained, a condition closely linked to the values of T/N ratio derived from BPA-PET.

Inflow-weighted pulmonary perfusion: comparison between dynamic contrast-enhanced MRI versus perfusion scintigraphy in complex pulmonary circulation.

BACKGROUND: Due to the different properties of the contrast agents, the lung perfusion maps as measured by 99mTc-labeled macroaggregated albumin perfusion scintigraphy (PS) are not uncommonly discrepant from those measured by dynamic contrast-enhanced MRI (DCE-MRI) using indicator-dilution analysis in complex pulmonary circulation. Since PS offers the pre-capillary perfusion of the first-pass transit, we hypothesized that an inflow-weighted perfusion model of DCE-MRI could simulate the result by PS. METHODS: 22 patients underwent DCE-MRI at 1.5T and also PS. Relative perfusion contributed by the left lung was calculated by PS (PS(L%)), by DCE-MRI using conventional indicator dilution theory for pulmonary blood volume (PBV(L%)) and pulmonary blood flow (PBFL%) and using our proposed inflow-weighted pulmonary blood volume (PBV(iw)(L%)). For PBViw(L%), the optimal upper bound of the inflow-weighted integration range was determined by correlation coefficient analysis. RESULTS: The time-to-peak of the normal lung parenchyma was the optimal upper bound in the inflow-weighted perfusion model. Using PSL% as a reference, PBV(L%) showed error of 49.24% to -40.37% (intraclass correlation coefficient R(I) = 0.55) and PBF(L%) had error of 34.87% to -27.76% (R(I) = 0.80). With the inflow-weighted model, PBV(iw)(L%) had much less error of 12.28% to -11.20% (R(I) = 0.98) from PS(L%). CONCLUSIONS: The inflow-weighted DCE-MRI provides relative perfusion maps similar to that by PS. The discrepancy between conventional indicator-dilution and inflow-weighted analysis represents a mixed-flow component in which pathological flow such as shunting or collaterals might have participated.

Extrastriatal 99m Tc-TRODAT-1 Uptake in the Previous Hemorrhage With Hemosiderin Deposition.

ABSTRACT: We reported a 91-year-old man who was suspected of having parkinsonism, and brain 99m Tc-TRODAT-1 scan revealed an extrastriatal uptake in the left side of brainstem, which was correlated to a previously hemorrhagic lesion with hemosiderin deposition. Macrophage or microglia might accumulate in the previous hemorrhagic lesion to phagocytize hemosiderin. We assumed that the 99m Tc-TRODAT-1 uptake in the hemosiderin deposition might be partially mediated by macrophage expressing dopamine transporter.

Radiation issue in clinical nuclear molecular imaging.

Radiation is ubiquitous in nature, and radiation is also widely used in various fields of medicine, agriculture, and industry. Current biological doses below 100 mSv are called low-dose radiation (LDR). Scientists have no consensus of effects on humans below this dose, so a variety of dose-response curve theories have been derived. This approach makes the public believe that even a small dose of radiation has adverse side effects, and overreact to refuse the related medical procedures for fear of radiation. The linear non-threshold (LNT) model has been used in radiation protection for over 40 years however, adverse effects from low dose, low-dose rate (LDDR) exposures are not detectable. Nuclear molecular imaging is LDR, using different radionuclides or combining with specific ligands (carries) to form "radiopharmaceuticals" for functional or pathological evaluations of diseases. As an integral part of patient care, nuclear medicine is used in the diagnosis, management, treatment, follow-up, and prevention of diseases. Therefore, this paper discusses literature review and provides appropriate scientific data and communication to help the peers and the public understand its advantage and disadvantage.

Comparison of the Detection Performance Between FAP and FDG PET/CT in Various Cancers: A Systemic Review and Meta-analysis.

PURPOSE: 18F-FDG is the dominant radiotracer in oncology; however, it has limitations. Novel labeled fibroblast activation protein (FAP) radiotracers have been developed and published in several studies. Thus, this meta-analysis aimed to compare the detection rates (DRs) of FDG and FAP, based on previous studies from a systematic review. METHODS: PubMed/MEDLINE and Cochrane library databases were used to perform a comprehensive and systematic search and are updated to April 30, 2022. The DR, relative risk, and the SUVmax were calculated between the FAP and FDG tracers. Finally, the sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristic curve of FAP and FDG were analyzed using gold and reference standards. RESULTS: Thirty studies (1170 patients) were included in the meta-analysis. The relative risks of FAP DR for the primary tumor, recurrent tumor, lymph node metastasis, and distant metastasis were FDG 1.06- to 3.00-fold per patient and per lesion. For the primary tumor, FAP uptake was most intense in pancreatic cancer, followed by head and neck, cervical, colorectal, lung, gastric, and hepatocellular carcinoma, and was higher than FDG except for urological system cancer. The sensitivity (0.84-0.98), diagnostic odds ratio (19.36-358.47), and summary receiver operating characteristic curve (0.94-0.99) of FAP based on patient and lesion were better for primary tumors, LN metastasis, and distant metastasis than FDG. CONCLUSIONS: Fibroblast activation protein is an extremely potential radiotracer to replace most of the use of FDG in oncology. It is noteworthy that the FAP tracers for primary tumors had low specificity despite excellent sensitivity and had lower uptake than FDG in urological system cancer. In addition, the difference in detection between FAP and FDG for LN metastasis could not be certain in sarcoma.

Comparison of the synthesis and biological properties of no-carrier-added and carrier-added 4-borono-2-[18F]fluorophenylalanine ([18F]FBPA).

PURPOSE: Boron neutron capture therapy (BNCT), an attractive strategy for cancer treatment, can kill tumor cells and avoid injury to surrounding healthy cells. 4-Borono-2-[18F]fluorophenylalanine ([18F]FBPA) positron emission tomography (PET) is a reliable tool for patient screening. Due to the relatively low radiochemical yield when employing the electrophilic route, this study was able to develop a new method to produce no-carrier-added (NCA) [18F]FBPA and compare the biological characteristics with carrier-added (CA) characteristics. PROCEDURES: By starting from 4-bromo-2-nitrobenzaldehyde, NCA [18F]FBPA was prepared using radiofluorination, alkylation, borylation, and hydrolysis. Cellular uptake analyses, microPET imaging, and biodistribution analyses were conducted to characterize the biological properties of NCA and CA [18F]FBPA. RESULTS: The radiochemical yield of NCA [18F]FBPA was 20 % ± 6 % (decay corrected) with a radiochemical purity of >98 % and molar activity of 56 ± 15 GBq/µmol in a 100-min synthesis. The in vitro accumulation was significantly higher for NCA [18F]FBPA than for CA [18F]FBPA in both SAS and CT-26 cells. However, no apparent differences in tumor uptake were observed between NCA and CA [18F]FBPA-injected tumor-bearing mice. CONCLUSIONS: We successfully prepared NCA [18F]FBPA through nucleophilic substitution and achieved improved radiochemical yield and purity. We also demonstrated the effects of the amount of nonradioactive FBPA on in vitro cellular uptake and in vivo imaging studies.

Follow-up Tc-99 m pyrophosphate cardiac scan for patients with transthyretin cardiac amyloidosis treated with tafamidis.

BACKGROUND: Tafamidis has been used for treatment of transthyretin cardiac amyloidosis (ATTR-CA). However, Tc-99 m pyrophosphate (PYP) cardiac scan for follow-up after tafamidis therapy has not been reported. METHODS: From May 2017 to March 2022, five patients with or without tafamidis therapy had received two Tc-99 m PYP cardiac scans. Tc-99 m PYP cardiac scan was performed with planar image and single photon emission computed tomography/computed tomography (SPECT/CT) 3 h after administration of Tc-99 m PYP. Perugini grading system was applied to determine positive or negative result of the scan. Heart to contralateral lung (H/CL) ratio as well as the difference of H/CL ratio between first and second Tc-99 m PYP cardiac scans (ΔH/CL ratio) was calculated. RESULTS: In the five patients participated in this study, three received tafamidis therapy and H/CL ratio was significantly decreased (p = 0.02) after tafamidis therapy. Besides, the ΔH/CL ratio was larger in patients with tafamidis therapy than that in those without tafamidis therapy, albeit not reaching statistical significance (p = 0.2). CONCLUSION: A decrease in H/CL ratio was found after tafamidis therapy in patients with ATTR-CA, albeit the magnitude of changes in the H/CL ratio (ΔH/CL ratio) was not significantly different from that of patients without tafamidis therapy. Future study with larger population might be required to further clarify the effect of tafamidis therapy on myocardial uptake of Tc-99 m PYP. CLINICAL TRIAL REGISTRATION: No clinical trial was conducted in our retrospective study.

CT of coronary heart disease: Part 2, Dual-phase MDCT evaluates late symptom recurrence in ST-segment elevation myocardial infarction patients after revascularization.

OBJECTIVE: The purpose of the study was to investigate dual-phase MDCT for assessing obstructive lesions and the extent and severity of the subtending myocardium at risk in patients presenting with chest pain syndromes 9 or more months after having undergone revascularization for the treatment of ST-segment elevation myocardial infarction (STEMI). MATERIALS AND METHODS: Dual-phase 64-MDCT was performed on 135 patients with recurring chest symptoms 9 months or more after revascularization (mean ± SD, 23 ± 11 months after index invasive angiogram for treatment of STEMI). Obstructive lesions (≥ 50% stenosis) were detected by MDCT angiography and the extent of myocardium at risk was detected by delayed phase 3D myocardium maps. A myocardium at-risk score based on MDCT findings was defined as the extent of myocardium at risk governed by the coronary lesion and weighted by lesion severity. Results were compared with stress-redistribution (201)Tl-SPECT and invasive angiography. RESULTS: In restenotic, new, progressive, and previously obstructive lesions that are not currently progressive, analysis of assessable segments (1966/2025, 97.1%) obtained true-positive detection rates of 88.1%, 88.6%, 82.9%, and 100%, respectively; false-negative detection rates were 5.3%, 1.6%, 2.9%, and 8.8%. In 124 patients (91.9%) in whom all segments were assessable, the MDCT-based myocardium at-risk score correlated with the SPECT-based summed difference score (SDS) (r = 0.841, p < 0.001). For detecting SPECT-based SDS ≥ 1 and SDS > 3, areas under the receiver operating characteristic curve for the MDCT-based myocardium at-risk score were 0.874 (95% CI, 0.805-0.942) and 0.938 (95% CI, 0.895-0.981), with optimal cutoff values of 2.68 and 5.01, respectively. CONCLUSION: Dual-phase MDCT is useful in detecting different patterns of obstructive lesions and the extent of myocardium at risk as an alternative for therapeutic planning in patients presenting with late symptoms after treatment for acute myocardial infarction.

Sequential therapy achieves a higher eradication rate than standard triple therapy in Taiwan.

BACKGROUND AND AIMS: Most clinical trials concerning sequential therapy have been conducted in Italy. The efficacy of sequential therapy for Helicobacter pylori (H. pylori) eradication in Asia remains unclear. The aim of this study was to compare the efficacy of sequential therapy with standard triple therapy in Taiwan. METHODS: From January 2005 to December 2009, 233 H. pylori-infected patients receiving either a 10-day sequential therapy (40 mg pantoprazole and 1 g amoxicillin, twice daily, for the initial 5 days, followed by 40 mg pantoprazole, 500 mg clarithromycin, and 500 mg metronidazole, twice daily, for the subsequent 5 days, n = 118) or a 7-day standard triple therapy (40 mg pantoprazole, 500 mg clarithromycin, and 1 g amoxicillin twice daily for 7 days, n = 115) were included in the retrospective study. All the patients underwent a follow-up endoscopy with a rapid urease test and histological examination or a urea breath test at 8 weeks after the end of anti-H. pylori therapy to assess H. pylori status. RESULT: Intention-to-treat analysis demonstrated a significantly higher eradication rate for the sequential group than for the triple group (93% vs 80%, respectively, P = 0.003). Per-protocol analysis also showed similar results (93% vs 80%, P = 0.005). Both groups had similar frequencies of adverse events (29% vs 22%) and drug compliance (98% vs 97%). CONCLUSION: Sequential therapy achieves a higher eradication rate than standard triple therapy in Taiwan. The novel treatment can be used as a first-line therapy for H. pylori infection for Taiwanese.