Progression-Free Survival in Patients with WHO-2 Meningioma Undergoing Active Surveillance Based on DOTATATE PET Evidence of Gross Total Resection: Prospective Observational Study

PURPOSE/OBJECTIVE(S)

MRI is the standard of care for meningioma radiotherapy planning, but lacks sensitivity for postoperative small volume disease and osseous or parenchymal invasion. NRG-BN003 (NCT03180268) randomizes patients with WHO-2 meningiomas and MRI-determined gross total resection (GTR) to observation or 60 Gy IMRT to the resection bed. More sensitive and specific imaging biomarkers than MRI may improve clinical outcomes in meningioma by limiting unnecessary irradiation of normal tissues and improving radiotherapy targeting. [68Ga]-DOTATATE, a PET radiotracer targeting somatostatin receptor 2 (SSTR2) is a highly sensitive and specific meningioma biomarker. Our dedicated DOTATATE brain PET/MRI and PET/CT protocol allows meningioma differentiation from post-treatment change, using SUV analysis and Patlak modeling. Our prospective IRB-approved observational trial (NCT04081701) has imaged >100 patients with meningioma. In the sub-analysis presented here, we prospectively evaluated PFS in patients with WHO-2 tumors and postoperative GTR as determined by [68Ga]-DOTATATE brain PET/MRI or PET/CT who were managed solely with active surveillance. We hypothesized that the PFS of patients with GTR by PET managed with active surveillance would be higher than reported PFS data for patients with MRI-determined GTR, using NRG-BN003's observation arm (randomized trial comparing observation to fractionated RT) as a reference standard.

MATERIALS/METHODS

From the cohort of >100 patients with SSTR2-positive brain neoplasms enrolled between 9/2019 and 10/2022 and imaged according to our previously published protocol, a sub-cohort of patients were selected with WHO-2 meningioma, postoperative findings of GTR, and postoperative active surveillance with periodic MRI every 3-6 months. Kaplan-Meier survival analysis was performed.

RESULTS

A total of 12 patients met inclusion criteria. Mean patient age was 64 years and 5 (42%) were female. Mean follow up period was 23.4 months (range: 7-38). 83% (10/12) patients underwent postoperative PET/MRI and 17% (2/12) underwent PET/CT. 2 patients (17%) progressed, at 22 and 34 months, respectively; the remainder remain progression-free. Both patients who had progression were successfully salvaged with focal fractionated radiosurgery. Kaplan-Meier analysis demonstrated PFS at almost 3 years to be 75%, which is substantially higher than the reported 3-year PFS of 60% in the literature. Overall survival was 100%.

CONCLUSION

[68Ga]-DOTATATE PET can improve the specificity of imaging-based assessment of the extent of resection of WHO-2 meningiomas, thereby improving clinical outcomes. In this cohort of patients with completely resected WHO-2 meningiomas (as assessed by postoperative gadolinium-enhanced MRI and DOTATATE PET) who are conservatively managed, recurrences have been rare and amenable to radiosurgical salvage.

Electron field emitters made of 3-D CuO nanowires on flexible silicon substrate fabricated by heating Cu rods with through silicon via process

Cu rods with a diameter of 10 μm on a flexible silicon substrate were fabricated using the through silicon via (TSV) process and chemical mechanical polishing (CMP).

Evaluation of dose conversion coefficients for external exposure using Taiwanese reference man and woman

Reference man has been widely used for external and internal dose evaluation of radiation protection. The parameters of the mathematical model of organs suggested by the International Commission of Radiological Protection (ICRP) are adopted from the average data of Caucasians. However, the organ masses of Asians are significantly different from the data of Caucasians, leading to potentially dosimetric errors. In this study, a total of 40 volunteers whose heights and weights corresponded to the statistical average of Taiwanese adults were recruited. Magnetic resonance imaging was performed, and T2-weighted images were acquired. The Taiwanese reference man and woman were constructed according to the measured organ masses. The dose conversion coefficients (DCFs) for anterior-posterior (AP), posterior-anterior (PA), right lateral (RLAT) and left lateral (LLAT) irradiation geometries were simulated. For the Taiwanese reference man, the average differences of the DCFs compared with the results of ICRP-74 were 7.6, 5.1 and 11.1 % for 0.1, 1 and 10 MeV photons irradiated in the AP direction. The maximum difference reached 51.7 % for the testes irradiated by 10 MeV photons. The size of the trunk, the volume and the geometric position of organs can cause a significant impact on the DCFs for external exposure of radiation. The constructed Taiwanese reference man and woman can be used in radiation protection to increase the accuracy of dose evaluation for the Taiwanese population.

Xanthogranulomatous inflammation of terminal ileum: report of a case with small bowel involvement

Xanthogranulomatous inflammation is a rare pathological condition most frequently detected in the kidney and gallbladder. Reported herein is a case of xanthogranulomatous inflammation in a 51-year-old male presenting as a mass-forming lesion in the terminal ileum with mucosal ulceration. Diagnostic laparoscopy followed by ileocecectomy was performed due to intra-operative suspicion of carcinoma of appendix. This is a report of the condition involving the terminal ileum with mucosal ulceration and full-thickness involvement of bowel wall which are uncommon features of xanthogranulomatous inflammation in previously reported lower gastro-intestinal tract lesions.

Conductive microcapsules for self-healing electric circuits

Well dispersed conductive microcapsules can be processed directly with inorganic-based Ag paste and perform high restoration efficiency for as-cast electrical circuits.

Effects of humidity and ultraviolet characteristics on β-Ga2O3 nanowire sensor

Monoclinic gallium oxide (β-Ga₂O₃) nanowires (NWs) were synthesized via a vapor–liquid–solid mechanism by heating a GaN/sapphire template.

Improvements on a patient-specific dose estimation system in nuclear medicine examination

The purpose of this paper is to develop a patient-specific dose estimation system in nuclear medicine examination. A dose deposition routine to store the deposited energy of the photons during their flights was embedded in the widely used SimSET Monte Carlo code and a user-friendly interface for reading PET and CT images was developed. Dose calculated on ORNL phantom was used to validate the accuracy of this system. The ratios of S value for (99m)Tc, (18)F and (131)I computed by this system to those obtained with OLINDA for various organs were ranged from 0.93 to 1.18, which were comparable to that obtained from MCNPX2.6 code (0.88-1.22). Our system developed provides opportunity for tumor dose estimation which cannot be known from the MIRD. The radiation dose can provide useful information in the amount of radioisotopes to be administered in radioimmunotherapy.

Design and testing of a uniformly solar energy TIR-R concentration lenses for HCPV systems

In this paper, total internal reflection-refraction (TIR-R) concentration (U-TIR-R-C) lens module were designed for uniformity using the energy configuration method to eliminate hot spots on the surface of solar cell and increase conversion efficiency. The design of most current solar concentrators emphasizes the high-power concentration of solar energy, however neglects the conversion inefficiency resulting from hot spots generated by uneven distributions of solar energy concentrated on solar cells. The energy configuration method proposed in this study employs the concept of ray tracing to uniformly distribute solar energy to solar cells through a U-TIR-R-C lens module. The U-TIR-R-C lens module adopted in this study possessed a 76-mm diameter, a 41-mm thickness, concentration ratio of 1134 Suns, 82.6% optical efficiency, and 94.7% uniformity. The experiments demonstrated that the U-TIR-R-C lens module reduced the core temperature of the solar cell from 108 °C to 69 °C and the overall temperature difference from 45 °C to 10 °C, and effectively relative increased the conversion efficiency by approximately 3.8%. Therefore, the U-TIR-R-C lens module designed can effectively concentrate a large area of sunlight onto a small solar cell, and the concentrated solar energy can be evenly distributed in the solar cell to achieve uniform irradiance and effectively eliminate hot spots.

Dose point kernel simulation for monoenergetic electrons and radionuclides using Monte Carlo techniques

Monte Carlo (MC) simulation has been commonly used in the dose evaluation of radiation accidents and for medical purposes. The accuracy of simulated results is affected by the particle-tracking algorithm, cross-sectional database, random number generator and statistical error. The differences among MC simulation software packages must be validated. This study simulated the dose point kernel (DPK) and the cellular S-values of monoenergetic electrons ranging from 0.01 to 2 MeV and the radionuclides of (90)Y, (177)Lu and (103 m)Rh, using Fluktuierende Kaskade (FLUKA) and MC N-Particle Transport Code Version 5 (MCNP5). A 6-μm-radius cell model consisting of the cell surface, cytoplasm and cell nucleus was constructed for cellular S-value calculation. The mean absolute percentage errors (MAPEs) of the scaled DPKs, simulated using FLUKA and MCNP5, were 7.92, 9.64, 4.62, 3.71 and 3.84 % for 0.01, 0.1, 0.5, 1 and 2 MeV, respectively. For the three radionuclides, the MAPEs of the scaled DPKs were within 5 %. The maximum deviations of S(N←N), S(N←Cy) and S(N←CS) for the electron energy larger than 10 keV were 6.63, 6.77 and 5.24 %, respectively. The deviations for the self-absorbed S-values and cross-dose S-values of the three radionuclides were within 4 %. On the basis of the results of this study, it was concluded that the simulation results are consistent between FLUKA and MCNP5. However, there is a minor inconsistency for low energy range. The DPK and the cellular S-value should be used as the quality assurance tools before the MC simulation results are adopted as the gold standard.

GaN epitaxial layers prepared on nano-patterned Si(001) substrate

We report the growth of GaN epitaxial layer on Si(001) substrate with nano-patterns prepared by dry etching facility used in integrated circuit (IC) industry. It was found that the GaN epitaxial layer prepared on nano-patterned Si(001) substrate exhibits both cubic and hexagonal phases. It was also found that threading dislocation observed from GaN prepared on nano-patterned Si(001) substrate was significantly smaller than that prepared on conventional unpatterned Si(111) substrate. Furthermore, it was found that we can reduce the tensile stress in GaN epitaxial layer by about 78% using the nano-patterned Si(001) substrate.

A ZnO-nanowire phototransistor prepared on glass substrates

The fabrication of a phototransistor via the bridging of two prefabricated electrodes with a laterally grown ZnO nanowire is reported. It was found that the fabricated device is an n-channel enhancement-mode phototransistor with a dark carrier concentration of 6.34 × 10(17) cm(-3) when the gate voltage is biased at 5 V. With an incident-light wavelength of 360 nm and a zero gate bias, it was found that the noise equivalent power and normalized detectivity (D*) of the fabricated ZnO phototransistor were 6.67 × 10(-17) W and 1.27 × 10(13) cm Hz(0.5) W(-1), respectively. It was also found that the current in the device can be modulated efficiently by tuning the wavelength of the excitation source.

Quaternary ZnCdSeTe nanowires

We report the growth of needle-like high density quaternary ZnCdSeTe nanowires on oxidized Si(100) substrate using vapor-liquid-solid mechanism by molecular beam epitaxy with an Au-based nanocatalyst. It was found that average length and average diameter of the nanowires were 1.3 microm and 91 nm, respectively. It was also found that the as-grown ZnCdSeTe nanowires exhibit mixture of cubic zinc-blende and hexagonal wurtzite structures. Energy depersive results indicate that composition ratio of our nanowire should be Zn0.87Cd0.13Se0.98Te0.02, which agrees excellently with the designated composition ratio of Zn0.87Cd0.13Se0.98Te0.02.

Structural characteristic, Raman analysis and optical properties of indium-doped ZnO nanoparticles prepared by sol-gel method

Un-doped and indium (0-9 at.%) doped ZnO nanoparticles were prepared by the sol-gel method. The nanoparticles were heated at 700 degrees C-800 degrees C for 1 hour in air and then analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDS), Raman spectra and photoluminescence (PL). The results were compared to investigate the structural characteristics and physical properties. XRD patterns of the Indium-doped ZnO (IZO) nanoparticles were similar to those of the ZnO nanoparticles. Notably, the crystalline quality of the ZnO nanoparticles had reduced with increasing the concentration of indium doping. The In2O3 phase of IZO and the crystallized structures affected the UV emission band and the green emission band of PL. The Indium-doped (5 at.% - 7 at.%) ZnO nanoparticles possessed higher crystalline quality and better optical properties.

Role of HPV DNA testing for detection of high-grade cervical lesions in women with atypical squamous cells of undetermined significance: a prospective study in a Korean population

OBJECTIVE

The purpose of this study was to determine if HPV DNA testing improves the accuracy of detecting possible high-grade cervical lesions in women with atypical squamous cells of undetermined significance (ASC-US).

METHODS

Cervical cytology and Hybrid Capture II (HCII) assay for HPV DNA detection was performed in 10,526 women from July 2005 to July 2007. Two hundred and sixty women with ASC-US underwent colposcopy-directed biopsy to determine the final histologic diagnosis. They were divided into two groups according to the positivity of the HPV DNA test, and the respective biopsy results were compared.

RESULTS

Positive HCII was significantly more associated with CIN 2, CIN 3, and invasive cancer than negative HCII (p < 0.001). The odds ratio of positive HPV DNA testing in detecting high-grade lesions was 7.0 (95% CI; 2.8-17.7).

CONCLUSION

The HPV DNA test is useful for predicting the severity of lesions of the uterine cervix and formulating decisions with regard to treatment plans.

Accuracy of preoperative magnetic resonance imaging in assessing lymph node metastasis and myometrial invasion in patients with uterine cancer

OBJECTIVES

Our aim was to know preoperative magnetic resonance imaging (MRI) can accurately predict lymph node metastasis (LNM) and deep myometrial invasion (DMI, > or = 50%) in patients with uterine cancer.

METHODS

From January 1997 to December 2006, 99 patients who were diagnosed with uterine cancer and surgically staged at our institution were retrospectively analyzed. Preoperative clinicopathologic characteristics and MRI findings were reviewed and compared with LNM status and DMI observed in the final pathology.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) for MRI in determination of pelvic LNM were 77.7%, 85.6%, 35.0%, and 94.7%, respectively. MRI failed to detect the presence of paraaortic LNM in all of the three patients with positive paraaortic lymph nodes. The sensitivity, specificity, PPV, and NPV for MRI in determining DMI were 46.6%, 84.5%, 35%, and 89.8%, respectively.

CONCLUSION

Preoperative evaluation of uterine cancer by MRI does not accurately predict the LNM and DMI.

Erratum: ZnO-based MIS photodetectors

[This corrects the article DOI: 10.1016/j.sna.2007.06.006.].

Analysis of colonoscopic findings in the differential diagnosis between intestinal tuberculosis and Crohn's disease

BACKGROUND AND STUDY AIMS

Intestinal tuberculosis and Crohn's disease are chronic inflammatory bowel disorders that are difficult to differentiate from one another. This study aimed to evaluate the diagnostic value of various colonoscopic findings in the differential diagnosis between intestinal tuberculosis and Crohn's disease.

PATIENTS AND METHODS

Colonoscopic findings on initial work-up were prospectively recorded in patients with an initial diagnosis of either intestinal tuberculosis or Crohn's disease. These findings were analyzed after a final diagnosis of intestinal tuberculosis (n = 44) or Crohn's disease (n = 44) had been made after follow-up.

RESULTS

Four parameters (anorectal lesions, longitudinal ulcers, aphthous ulcers, and cobblestone appearance) were significantly more common in patients with Crohn's disease than in patients with intestinal tuberculosis. Four other parameters (involvement of fewer than four segments, a patulous ileocecal valve, transverse ulcers, and scars or pseudopolyps) were observed more frequently in patients with intestinal tuberculosis than in patients with Crohn's disease. We hypothesized that a diagnosis of Crohn's disease could be made when the number of parameters characteristic of Crohn's disease was higher than the number of parameters characteristic of intestinal tuberculosis, and vice versa. Making these assumptions, we calculated that the diagnosis of either intestinal tuberculosis or Crohn's disease would have been made made correctly in 77 of our 88 patients (87.5 %), incorrectly in seven patients (8.0 %), and would not have been made in four patients (4.5 %).

CONCLUSIONS

A systematic analysis of colonoscopic findings is very useful in the differential diagnosis between intestinal tuberculosis and Crohn's disease.