Optimal glycaemic control and the reduced risk of colorectal adenoma and cancer in patients with diabetes: a population-based cohort study

OBJECTIVE

Whether varying degrees of glycaemic control impact colonic neoplasm risk in patients with diabetes mellitus (DM) remains uncertain.

DESIGN

Patients with newly diagnosed DM were retrieved from 2005 to 2013. Optimal glycaemic control at baseline was defined as mean haemoglobin A1c (HbA1c)<7%. Outcomes of interest included colorectal cancer (CRC) and colonic adenoma development. We used propensity score (PS) matching with competing risk models to estimate subdistribution HRs (SHRs). We further analysed the combined effect of baseline and postbaseline glycaemic control based on time-weighted mean HbA1c during follow-up.

RESULTS

Of 88 468 PS-matched patients with DM (mean (SD) age: 61.5 (±11.7) years; male: 47 127 (53.3%)), 1229 (1.4%) patients developed CRC during a median follow-up of 7.2 (IQR: 5.5-9.4) years. Optimal glycaemic control was associated with lower CRC risk (SHR 0.72; 95% CI 0.65 to 0.81). The beneficial effect was limited to left-sided colon (SHR 0.71; 95% CI 0.59 to 0.85) and rectum (SHR 0.71; 95% CI 0.57 to 0.89), but not right-sided colon (SHR 0.86; 95% CI 0.67 to 1.10). Setting suboptimal glycaemic control at baseline/postbaseline as a reference, a decreased CRC risk was found in optimal control at postbaseline (SHR 0.79), baseline (SHR 0.71) and both time periods (SHR 0.61). Similar associations were demonstrated using glycaemic control as a time-varying covariate (HR 0.75). A stepwise greater risk of CRC was found (Ptrend<0.001) with increasing HbA1c (SHRs 1.34, 1.30, 1.44, 1.58 for HbA1c 7.0% to <7.5%, 7.5% to <8.0%, 8.0% to <8.5% and ≥8.5%, respectively). Optimal glycaemic control was associated with a lower risk of any, non-advanced and advanced colonic adenoma (SHRs 0.73-0.87).

CONCLUSION

Glycaemic control in patients with DM was independently associated with the risk of colonic adenoma and CRC development with a biological gradient.

Hong Kong consensus recommendations on the management of pancreatic ductal adenocarcinoma

This project was undertaken to develop the first set of consensus statements regarding the management of pancreatic ductal adenocarcinoma (PDAC) in Hong Kong, with the goal of providing guidance to local clinicians. A multidisciplinary panel of experts discussed issues surrounding current PDAC management and reviewed evidence gathered in the local context to propose treatment recommendations. The experts used the Delphi approach to finalise management recommendations. Consensus was defined as ≥80% acceptance among all expert panel members. Thirty-nine consensus statements were established. These statements cover all aspects of PDAC management, including diagnosis, resectability criteria, treatment modalities according to resectability, personalised management based on molecular profiling, palliative care, and supportive care. This project fulfils the need for guidance regarding PDAC management in Hong Kong. To assist clinicians with treatment decisions based on varying levels of evidence and clinical experience, treatment options are listed in several consensus statements.

Prognostic PET [11C]-acetate uptake is associated with hypoxia gene expression in patients with late-stage hepatocellular carcinoma - a bench to bed study

BACKGROUND

Positron Emission Tomography (PET) with combined [18F]-FDG and [11C]-acetate (dual-tracer) is used for the management of hepatocellular carcinoma (HCC) patients, although its prognostic value and underlying molecular mechanism remain poorly understood. We hypothesized that radiotracer uptake might be associated with tumor hypoxia and validated our findings in public and local human HCC cohorts.

METHODS

Twelve orthotopic HCC xenografts were established using MHCC97L cells in female nude mice, with 5 having undergone hepatic artery ligation (HAL) to create tumor hypoxia in vivo. Tumors in both Control and HAL-treated xenografts were imaged with [11C]-acetate and [18F]-FDG PET-MR and RNA sequencing was performed on the resected tumors. Semiquantitative analysis of PET findings was then performed, and the findings were then validated on the Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) cohort and patients from our institution.

RESULTS

HAL-treated mice showed lower [11C]-acetate (HAL-treated vs. Control, tumor-to-liver SUV ratio (SUVTLR): 2.14[2.05-2.21] vs 3.11[2.75-5.43], p = 0.02) but not [18F]-FDG (HAL-treated vs. Control, SUVTLR: 3.73[3.12-4.35] vs 3.86[3.7-5.29], p = 0.83) tumor uptakes. Gene expression analysis showed the PET phenotype is associated with upregulation of hallmark hypoxia signature. The prognostic value of the hypoxia gene signature was tested on the TCGA-LIHC cohort with upregulation of hypoxia gene signature associated with poorer overall survival (OS) in late-stage (stage III and IV) HCC patients (n = 66, OS 2.05 vs 1.67 years, p = 0.046). Using a local cohort of late-stage HCC patients who underwent dual-tracer PET-CT, tumors without [11C]-acetate uptake are associated with poorer prognosis (n = 51, OS 0.25 versus 1.21 years, p < 0.0001) and multivariable analyses showed [11C]-acetate tumor uptake as an independent predictor of OS (HR 0.17 95%C 0.06-0.42, p < 0.0001).

CONCLUSIONS

[11C]-acetate uptake is associated with alteration of tumor hypoxia gene expression and poorer prognosis in patients with advanced HCC.

ImmuneMirror: A machine learning-based integrative pipeline and web server for neoantigen prediction

Neoantigens are derived from somatic mutations in the tumors but are absent in normal tissues. Emerging evidence suggests that neoantigens can stimulate tumor-specific T-cell-mediated antitumor immune responses, and therefore are potential immunotherapeutic targets. We developed ImmuneMirror as a stand-alone open-source pipeline and a web server incorporating a balanced random forest model for neoantigen prediction and prioritization. The prediction model was trained and tested using known immunogenic neopeptides collected from 19 published studies. The area under the curve of our trained model was 0.87 based on the testing data. We applied ImmuneMirror to the whole-exome sequencing and RNA sequencing data obtained from gastrointestinal tract cancers including 805 tumors from colorectal cancer (CRC), esophageal squamous cell carcinoma (ESCC) and hepatocellular carcinoma patients. We discovered a subgroup of microsatellite instability-high (MSI-H) CRC patients with a low neoantigen load but a high tumor mutation burden (> 10 mutations per Mbp). Although the efficacy of PD-1 blockade has been demonstrated in advanced MSI-H patients, almost half of such patients do not respond well. Our study identified a subset of MSI-H patients who may not benefit from this treatment with lower neoantigen load for major histocompatibility complex I (P < 0.0001) and II (P = 0.0008) molecules, respectively. Additionally, the neopeptide YMCNSSCMGV-TP53G245V, derived from a hotspot mutation restricted by HLA-A02, was identified as a potential actionable target in ESCC. This is so far the largest study to comprehensively evaluate neoantigen prediction models using experimentally validated neopeptides. Our results demonstrate the reliability and effectiveness of ImmuneMirror for neoantigen prediction.

Efficacy and feasibility of 3D printed redesigned Venezia™ applicator for treating advanced cervix and recurrent endometrial cancer

PURPOSE

Venezia™ is an interstitial brachytherapy applicator for treating advanced cervical and vaginal vault recurrent cancer. However, there are limitations that lead to suboptimal target coverage. 3D printing introduction allows the redesign of Venezia™ for bulky and irregular-shaped tumors.

METHODS

This study first describes three new designs included: 1) add-on needles template allowed for an extra layer of straight and oblique needles, 2) redesigned vaginal cap so straight and oblique needles can be used together and 3) redesigned central tube allowed vaginal vault interstitial needle insertion. Drawbacks to original Venezia™ and rationale for using these new designs were discussed. Dosimetric analysis by comparing the original Venezia™ with new design for 10 cases in Oncentra treatment planning system v4.5 (Elekta, Stockholm, Sweden) to observe the dose differences in gross tumor volume (GTV), high risk clinical target volume (HRCTV), intermediate clinical target volume (IRCTV) and organs at risk.

RESULTS

For the dosimetric comparison, there were statistically significantly increased median minimal dose to 98% (D98%) of GTV, 90% (D90%) of HRCTV, and IRCTV for the new design with p-value of 0.008, 0.005 and 0.0018, respectively. Comparing the physical dose of D98% of GTV, D90% of HRCTV, and IRCTV when using the new design, it averagely increased by 11.7%, 8.0%, 19.4%, respectively per fraction.

CONCLUSIONS

Dosimetric comparison revealed the new designs increased the dose to GTV, HRCTV and IRCTV and fulfilled the dose constraints of bladder, rectum and sigmoid. The 3D printed new design is biocompatible, inexpensive and can be patient specific.

Cardiovascular diseases among diffuse large B-cell lymphoma long-term survivors in Asia: a multistate model study

BACKGROUND

We modeled the clinical course of a cohort of diffuse large B-cell lymphoma (DLBCL) patients with no prior cardiovascular diseases (CVDs) using a multistate modeling framework.

PATIENTS AND METHODS

Data on 2600 patients with DLBCL diagnosed between 2000 and 2018 and had received chemotherapy with or without radiotherapy were obtained from a population-wide electronic health database of Hong Kong. We used the Markov illness-death model to quantify the impact of doxorubicin and various risk factors (therapeutic exposure, demographic, comorbidities, cardiovascular risk factors, and lifestyle factors which included smoking) on the clinical course of DLBCL (transitions into incident CVD, lymphoma death, and other causes of death).

RESULTS

A total of 613 (23.6%) and 230 (8.8%) of 2600 subjects died of lymphoma and developed incident CVD, respectively. Median follow-up was 7.0 years (interquartile range 3.8-10.8 years). Older ages [hazard ratio (HR) for >75 versus ≤60 years 1.88; 95% confidence interval (CI) 1.25-2.82 and HR for 61-75 versus ≤60 years 1.60; 95% CI 1.12-2.30], hypertension (HR 4.92; 95% CI 2.61-9.26), diabetes (HR 1.43; 95% CI 1.09-1.87), and baseline use of aspirin (HR 5.30; 95% CI 3.93-7.16) were associated with an increased risk of incident CVD. In a subgroup of anticipated higher-risk patients (aged 61-75 years, smoked, had diabetes, and received doxorubicin), we found that they remained on average 7.9 (95% CI 7.2-8.8) years in the DLBCL state and 0.1 (95% CI 0.0-0.4) years in the CVD state, if they could be followed up for 10 years. The brief time in the CVD state is consistent with the high chance of death in patients who developed CVD. Other causes of death have overtaken DLBCL-related death after about 5 years.

CONCLUSIONS

In this Asian population-based cohort, we found that incident CVDs can occur soon after DLBCL treatment and continued to occur throughout survivorship. Clinicians are advised to balance the risks and benefits of treatment choices to minimize the risk of CVD.

Comparison of clinical outcome between stereotactic body radiotherapy and radiofrequency ablation for unresectable hepatocellular carcinoma

Stereotactic body radiotherapy (SBRT) is a novel noninvasive treatment for unresectable hepatocellular carcinoma (HCC). Whether its efficacy is comparable to radiofrequency ablation (RFA), a recommended therapy for unresectable HCC, is unknown. The present study aims to compare the clinical outcome between SBRT and RFA for patients with unresectable HCC.The clinical data of 60 patients with unresectable HCC from January 2018 to January 2021 were retrospectively reviewed. There were 22 cases treated by SBRT and 38 cases by RFA. The short-term and long-term clinical outcomes were compared.There was no significant difference in the baseline demographic characteristics between two groups. The complete remission rate at 3 months was comparable between SBRT group (81.8%) and RFA group (89.4%). Local tumor control rate was also similar between two groups (90.9% vs. 94.7%). There was no severe complication (grade IIIa or above) in both groups. The 1-year and 2-year overall survival rates were 88.2% and 85.7% in SBRT group and 100% and 75% in RFA group, respectively. There was no statistical significant difference between groups (P = .576).SBRT can achieve similar short and long-term clinical outcome as RFA for unresectable HCC. Future prospective clinical study is needed to justify its role in patients with HCC.

Combined Stereotactic Body Radiotherapy and Immunotherapy Versus Transarterial Chemoembolization in Locally Advanced Hepatocellular Carcinoma: A Propensity Score Matching Analysis

Immunotherapy has achieved modest clinical activity in HCC patients. Propensity score matching analysis was conducted to compare the efficacy and safety of combined stereotactic SBRT-IO versus TACE in patients with locally advanced HCC in a tertiary center of Hong Kong. Patients with locally advanced HCC who were medically inoperable for, refractory to, or refused to curative surgical interventions were eligible. The primary outcome was PFS; the secondary outcomes were OS, ORR as per mRECIST version 1.1, and TRAEs. Matching pair analysis was performed to compare the clinical outcomes. A total of 226 patients were eligible. Approximately 16 patients in the SBRT-IO group were matched with 48 patients treated with TACE. The median tumor size was 10 cm (range: 2.9-19.6 cm) and 20.3% of the patients had portal vein invasion. The 12- and 24-month PFS were significantly better in the SBRT-IO group (93.3% vs 16.7% and 77.8% vs 2.1%, respectively, p <0.001); the 12- and 24-month OS were also better in the SBRT-IO arm (93.8% vs 31.3% and 80.4% vs 8.3%, respectively, p <0.001). The ORR was 87.5% (CR: 50%, PR: 37.5%) in SBRT-IO arm compared to 16.7% (CR: 2.4%, PR: 14.3%) in those receiving TACE alone (p <0.001). There were fewer ≥grade 3 TRAE (60.4% vs 18.8%, p = 0.004) and treatment discontinuations (25% vs 12.5%, p = 0.295) due to adverse events in the SBRT-IO arm. SBRT-IO had significant superior survival and less treatment toxicity than TACE in patients with locally advanced HCC. Our results provide rationale for studying this combination therapy in prospective randomized trials.

Combination atezolizumab, bevacizumab, pemetrexed and carboplatin for metastatic EGFR mutated NSCLC after TKI failure

INTRODUCTION

Acquired resistance to TKI is an important unmet need in the management of EGFR mutated lung cancer. Recent clinical trial IMPower150 suggested that combination approach with VEGF inhibitor, check point inhibitor immunotherapy and platinum-based chemotherapy was effective in oncogene driven lung cancer. The current trial examined the efficacy of a modified regimen in an EGFR mutated cohort.

METHODS

An open-labelled, single arm, phase II study was conducted in patients with EGFR mutated NSCLC who had progressed on at least one EGFR TKI. For those with T790M mutation, radiological progression on osimertinib was required for enrolment. Patients were treated with combination atezolizumab (1200 mg), bevacizumab (7.5 mg/kg), pemetrexed (500 mg/m2) and carboplatin (AUC 5) given once every 3 weeks until progression.

RESULTS

Forty patients were enrolled. Median age was 62 (range 45-76) years. More than one half (23/40, 57.5%) had progressed on osimertinib. PD-L1 expression was < 1% in 52.5%. Median follow-up time was 17.8 months. ORR was 62.5%. Median PFS was 9.4 months (95% CI: 7.6 - 12.1). One year OS was 72.5% (95% CI: 0.56-0.83). Treatment related grade 3 or above adverse events (AE) occurred in 37.5% (15/40). Immune-related AE occurred in 32.5% (13/40) patients. Quality of life measures of function and symptoms did not change significantly throughout the course of treatments. Post-trial rechallenge with EGFR TKI containing regimen resulted in PFS of 5.8 months (95% CI 3.9-10.0 months).

CONCLUSION

Combination approach of atezolizumab, bevacizumab, pemetrexed and carboplatin achieved promising efficacy in metastatic EGFR mutated NSCLC after TKI failure. The results were comparable with taxane based regimen of IMPower150 while toxicity profile was improved.

Revisiting the formalism of equivalent uniform dose based on the linear-quadratic and universal survival curve models in high-dose stereotactic body radiotherapy

Purpose

To examine the equivalent uniform dose (EUD) formalism using the universal survival curve (USC) applicable to high-dose stereotactic body radiotherapy (SBRT).

Materials and methods

For nine non-small-cell carcinoma cell (NSCLC) lines, the linear-quadratic (LQ) and USC models were used to calculate the EUD of a set of hypothetical two-compartment tumor dose–volume histogram (DVH) models. The dose was varied by ±5%, ±10%, and ±20% about the prescription dose (60 Gy/3 fractions) to the first compartment, with fraction volume varying from 1% and 5% to 30%. Clinical DVHs of 21 SBRT treatments of NSCLC prescribed to the 70–83% isodose lines were also considered. The EUD of non-standard SBRT dose fractionation (EUD_SBRT) was further converted to standard fractionation of 2 Gy (EUD_CFRT) using the LQ and USC models to facilitate comparisons between different SBRT dose fractionations. Tumor control probability (TCP) was then estimated from the LQ- and USC-EUD_CFRT.

Results

For non-standard SBRT fractionation, the deviation of the USC- from the LQ-EUD_SBRT is largely limited to 5% in the presence of dose variation up to ±20% to fractional tumor volume up to 30% in all NSCLC cell lines. Linear regression with zero constant yielded USC-EUD_SBRT = 0.96 × LQ-EUD_SBRT (r² = 0.99) for the clinical DVHs. Converting EUD_SBRT into standard 2‑Gy fractions by the LQ formalism produced significantly larger EUD_CFRT than the USC formalism, particularly for low \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha /\beta$$\end{document}α/β ratios and large fraction dose. Simplified two-compartment DVH models illustrated that both the LQ- and USC-EUD_CFRT values were sensitive to cold spot below the prescription dose with little volume dependence. Their deviations were almost constant for up to 30% dose increase above the prescription. Linear regression with zero constant yielded USC-EUD_CFRT = 1.56 × LQ-EUD_CFRT (r² = 0.99) for the clinical DVHs. The clinical LQ-EUD_CFRT resulted in median TCP of almost 100% vs. 93.8% with USC-EUD_CFRT.

Conclusion

A uniform formalism of EUD should be defined among the SBRT community in order to apply it as a single metric for dose reporting and dose–response modeling in high-dose-gradient SBRT because its value depends on the underlying cell survival model and the model parameters. Further investigations of the optimal formalism to derive the EUD through clinical correlations are warranted.

Electronic supplementary material

The online version of this article (10.1007/s00066-020-01713-w) contains supplementary material, which is available to authorized users.

Second primary cancer after intensity-modulated radiotherapy for nasopharyngeal carcinoma: A territory-wide study by HKNPCSG

OBJECTIVES

Long-term risk of second primary cancer (SPC) after definitive intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) remains unclear. This study aims to evaluate the risk, predictive factors and survival impact of SPC in a large territory-wide cohort of NPC survivors in an endemic region.

MATERIALS AND METHODS

In this multicenter study, consecutive NPC patients (n = 3166) who underwent definitive IMRT in all six public oncology centers in Hong Kong between 2001 and 2010 were included. SPC risks were quantified by standardized incidence ratios (SIRs) and absolute excess risks (AERs) estimated from corresponding age-, sex-, and calendar year-specific population cancer incidence data from the Hong Kong Cancer Registry. Predictive factors and SPC-specific mortality were analyzed.

RESULTS

Over a median follow-up period of 10.8 years, 290 cases of SPC were observed with a crude incidence of 9.2%. Cancer risk in NPC survivors was 90% higher than that in general population [SIR, 1.9; 95% confidence interval (CI), 1.7-2.2], with an AER of 52.1 (95% CI, 36.8-67.3) per 10,000 person-years at risk. Significant excess cancer risks were observed for oral cavity, sarcoma, oropharynx, paranasal sinus, salivary gland, thyroid, skin and lung. Advanced age, smoking, hepatitis B status, and re-irradiation were independent predictive factors. SPC accounted for 9.4% of all deaths among NPC survivors during the study period, and 10-year SPC-specific mortality was 3.4%.

CONCLUSIONS

Second cancer risk after IMRT was substantial among NPC patients. SPC impairs long-term survival, and close surveillance is warranted as part of survivorship care.

Efficacy and safety of radiotherapy for primary liver cancer

Primary liver cancer includes hepatocellular carcinoma (HCC, 75-85%) and intrahepatic cholangiocarcinoma (10-15%). The vast majority of patients with primary HCC are not candidates for surgical treatment. Surgical resection, liver transplantation and percutaneous puncture are effective potentially curable treatments for patients with early stage liver cancer. Radiation therapy is a non-surgical alternative treatment that has generally been used to treat patients with advanced liver cancer, although it's use in the potentially curative setting is increasing. Radiotherapy is a non-invasive local treatment which works through ionizing radiation. This review summarizes the efficacy and safety of commonly used radiotherapy methods, and reviews three-dimensional conformal radiotherapy (3DCRT), intensity modulated radiation therapy (IMRT), stereotactic body radiotherapy (SBRT), volume-modulated arc therapy (VMAT), and internal radiation therapies, for primary liver cancer (in particular for HCC).

On the pitfalls of PTV in lung SBRT using type-B dose engine: an analysis of PTV and worst case scenario concepts for treatment plan optimization

Background

PTV concept is presumed to introduce excessive and inconsistent GTV dose in lung stereotactic body radiotherapy (SBRT). That GTV median dose prescription (D₅₀) and robust optimization are viable PTV–free solution (ICRU 91 report) to harmonize the GTV dose was investigated by comparisons with PTV–based SBRT plans.

Methods

Thirteen SBRT plans were optimized for 54 Gy / 3 fractions and prescribed (i) to 95% of the PTV (D₉₅) expanded 5 mm from the ITV on the averaged intensity project (AIP) CT, i.e., PTV_ITV, (ii) to D₉₅ of PTV derived from the van Herk (VH)‘s margin recipe on the mid–ventilation (MidV)–CT, i.e., PTV_VH, (iii) to ITV D₉₈ by worst case scenario (WCS) optimization on AIP,i.e., WCS_ITV and (iv) to GTV D₉₈ by WCS using all 4DCT images, i.e., WCS_GTV. These plans were subsequently recalculated on all 4DCT images and deformably summed on the MidV–CT. The dose differences between these plans were compared for the GTV and selected normal organs by the Friedman tests while the variability was compared by the Levene’s tests. The phase–to–phase changes of GTV dose through the respiration were assessed as an indirect measure of the possible increase of photon fluence owing to the type–B dose engine. Finally, all plans were renormalized to GTV D₅₀ and all the dosimetric analyses were repeated to assess the relative influences of the SBRT planning concept and prescription method on the variability of target dose.

Results

By coverage prescriptions (i) to (iv), significantly smaller chest wall volume receiving ≥30 Gy (CW_V30) and normal lung ≥20 Gy (NL_V20Gy) were achieved by WCS_ITV and WCS_GTV compared to PTV_ITV and PTV_VH (p > 0.05). These plans differed significantly in the recalculated and summed GTV D₂, D₅₀ and D₉₈ (p <  0.05). The inter–patient variability of all GTV dose parameters is however equal between these plans (Levene’s tests; p > 0.05). Renormalizing these plans to GTV D₅₀ reduces their differences in GTV D₂, and D₉₈ to insignificant level (p > 0.05) and their inter–patient variability of all GTV dose parameters. None of these plans showed significant differences in GTV D₂, D₅₀ and D₉₈ between respiratory phases, nor their inter–phase variability is significant.

Conclusion

Inconsistent GTV dose is not unique to PTV concept but occurs to other PTV–free concept in lung SBRT. GTV D₅₀ renormalization effectively harmonizes the target dose among patients and SBRT concepts of geometric uncertainty management.

Toxicity outcome of endorectal brachytherapy boost in medically inoperable patients

AIM

This communication reviews results and toxicity of image-guided high-dose-rate endorectal brachytherapy (HDREBT) boost after external beam radiotherapy (ERT) in medically inoperable patients with rectal cancer.

MATERIALS AND METHODS

A total of 18 patients with rectal cancer and clinical stage T2-4N0‑2 treated with HDREBT boost after ERT were retrospectively reviewed.

RESULTS

Following treatment with a median total dose (EQD2, α/β = 10) of 66 Gy (range 48-92 Gy), the incidence of early and late rectal grade 3 toxicity was 11% and 19%, respectively. There was no correlation between the occurrence of acute and late toxicity.

CONCLUSION

With proper technique, a combined approach using EBRT and HDREBT was associated with acceptable toxicity in medically inoperable rectal cancer patients.

Palliative Liver Radiotherapy (RT) for Symptomatic Hepatocellular Carcinoma (HCC)

This study aims at evaluating the symptom response, response duration, and toxicity of single dose palliative liver radiotherapy (RT) for symptomatic HCC patients. We reviewed unresectable HCC patients treated with palliative RT in our institution. Eligible patients were unsuitable or refractory to trans-arterial chemoembolization (TACE) and stereotactic body radiotherapy (SBRT), with an index symptom of pain or abdominal discomfort. The primary outcome was the percentage of patients with clinical improvement of index symptom at 1 month. Secondary outcomes were response duration, toxicities, alpha-feto protein (AFP) response, and radiological response. Fifty-two patients were included in the study. The index symptom was pain in 34 patients (65.4%), and abdominal discomfort (34.6%) in 18 patients. At 1 month, 51.9% of patients had improvement of symptoms. Median time to symptom progression was 89 days (range: 12–392 days). Treatment was well tolerated with only 2 patients (3.8%) developing grade 3 GI toxicities. AFP response, radiological response rate, and disease control rate at 3 months were 48.6%, 15.1%, and 54.5% respectively. Half of the patients had improvement of index symptoms after receiving palliative liver RT with median response duration of 3 months. The treatment was well tolerated with minimal toxicities.

Combined Stereotactic Body Radiotherapy and Checkpoint Inhibition in Unresectable Hepatocellular Carcinoma: A Potential Synergistic Treatment Strategy

Background: Current treatments of unresectable hepatocellular carcinoma (HCC) are trans-arterial chemo-embolization (TACE), stereotactic body radiotherapy (SBRT), and targeted therapy. However, these treatments are limited in efficacy and safety for patients with large tumor sizes. Here, we report a case series of combined SBRT and anti-PD-1 therapy in patients with unresectable HCC of large tumors.

Methods: This is a retrospective case series of five patients with unresectable hepatocellular carcinoma who were treated with SBRT followed by anti-PD1 antibodies. Four patients (80%) received a single dose of TACE prior to SBRT. All patients had advanced HCC ineligible of curative intervention. In this study, we report their treatment responses according to modified RECIST (response evaluation criteria in solid tumor) criteria, 1-year local control (LC), progression-free survival (PFS), 1-year overall survival (OS) rate, and toxicities.

Results: Among the five evaluated patients, three patients had underlying diseases of hepatitis B and four patients had Barcelona clinic liver cancer stage C. The median size of their tumors was 9.8 cm (range: 9–16.1 cm). In addition, two patients had tumor vascular thrombosis and one had extra-hepatic disease. Five out of five patients (100%) responded to treatment, with two complete responses (CR) and three partial responses (PR). Among the partial responders, one had a down-staged tumor that became amenable for radiofrequency ablation for tumor clearance. No patient developed tumor progression at the time of analysis during the median follow-up of 14.9 months (range 8.6–19 months). The median PFS was 14.9 months (range: 8.6–19 months); 1-year LC and OS rate were both 100%. One patient had grade ≥ 3 toxicities (pneumonitis and skin reaction). There was no classical radiation-induced liver disease.

Conclusions: The results obtained from these 5 cases demonstrate impressive tumor control from the combination of SBRT and checkpoint inhibitors in patients with large tumors of advanced HCC. Further prospective trials are warranted.

International Guideline on Dose Prioritization and Acceptance Criteria in Radiation Therapy Planning for Nasopharyngeal Carcinoma

PURPOSE

The treatment of nasopharyngeal carcinoma requires high radiation doses. The balance of the risks of local recurrence owing to inadequate tumor coverage versus the potential damage to the adjacent organs at risk (OARs) is of critical importance. With advancements in technology, high target conformality is possible. Nonetheless, to achieve the best possible dose distribution, optimal setting of dose targets and dose prioritization for tumor volumes and various OARs is fundamental. Radiation doses should always be guided by the As Low As Reasonably Practicable principle. There are marked variations in practice. This study aimed to develop a guideline to serve as a global practical reference.

METHODS AND MATERIALS

A literature search on dose tolerances and normal-tissue complications after treatment for nasopharyngeal carcinoma was conducted. In addition, published guidelines and protocols on dose prioritization and constraints were reviewed. A text document and preliminary set of variants was circulated to a panel of international experts with publications or extensive experience in the field. An anonymized voting process was conducted to rank the proposed variants. A summary of the initial voting and different opinions expressed by members were then recirculated to the whole panel for review and reconsideration. Based on the comments of the panel, a refined second proposal was recirculated to the same panel. The current guideline was based on majority voting after repeated iteration for final agreement.

RESULTS

Variation in opinion among international experts was repeatedly iterated to develop a guideline describing appropriate dose prioritization and constraints. The percentage of final agreement on the recommended parameters and alternative views is shown. The rationale for the recommendations and the limitations of current evidence are discussed.

CONCLUSIONS

Through this comprehensive review of available evidence and interactive exchange of vast experience by international experts, a guideline was developed to provide a practical reference for setting dose prioritization and acceptance criteria for tumor volumes and OARs. The final decision on the treatment prescription should be based on the individual clinical situation and the patient's acceptance of optimal balance of risk.

Real-world treatment patterns and outcomes in refractory metastatic colorectal cancer

AIM

To investigate treatment patterns and outcomes of metastatic colorectal cancer (mCRC) patients beyond second progression (PD2) since regorafenib and TAS-102 became available in Hong Kong.

METHODS

The clinical records of consecutive mCRC patients who were treated beyond PD2 at Department of Clinical Oncology, Queen Mary Hospital between June 2013 and February 2018, were retrospectively reviewed.

RESULTS

Of 176 PD2 patients (76.7% Eastern Cooperative Oncology Group performance status 0/1 and a median follow-up time of 6.6 [range, 0.4-37.2] months), 104 (59%) underwent palliative care only and 72 (41%) received active third-line (3L) treatment: regorafenib (n = 22), TAS-102 (n = 6), chemotherapy + antiepidermal growth factor receptor (n = 12), chemotherapy + antivascular endothelial growth factor (n = 28) or clinical trials (n = 4). Patients on active 3L treatment had significantly longer OS than those on palliative care only: 11.7 versus 5.5 months (adjusted hazard ratio = 0.41, 95% confidence interval: 0.28-0.61, P < 0.001). For those on active treatment, OS was significantly associated with the time from diagnosis of metastasis to PD2 (P < 0.001) and post-3L treatments (P = 0.009). When analyzing treatment eligibility according to trial criteria, half of the eligible patients (54/109) did not receive active treatment, but both eligible and ineligible patients achieved better OS when receiving active 3L treatment versus palliative care only (P < 0.001 and P = 0.002). No unexpected toxicity was reported.

CONCLUSION

Active 3L and beyond treatment significantly prolonged OS versus palliative care, even in selected "trial ineligible" patients. Given a high rate of palliation only care in eligible patients, improved patient access to medicine and counseling may be needed to maximize outcomes.

Better survival after stereotactic body radiation therapy following transarterial chemoembolization in nonresectable hepatocellular carcinoma: A propensity score matched analysis

BACKGROUND

This study compared outcomes of nonresectable hepatocellular carcinoma (HCC) who had transarterial chemoembolization (TACE) vs. stereotactic body radiation therapy (SBRT) after TACE (TACE + SBRT).

METHODS

This was a retrospective study of 2 centers in Hong Kong. There were 49 patients who had TACE + SBRT and 202 patients who had TACE alone. Propensity score matching was used to adjust for differences in patients' demographics and tumor characteristics between the 2 groups. The primary outcome was overall survival (OS) and secondary outcomes were progression-free survival (PFS) and treatment-related toxicity.

RESULTS

After matching, 49 patients were in the TACE + SBRT group and 98 patients in the TACE group with similar baseline characteristics. The 1-&3-year OS were better in TACE + SBRT group (67.2 vs. 43.9% and 36.5 vs. 13.3%, p = 0.003). The 1-&3-year PFS was also better in TACE + SBRT group (32.5 vs. 21.4% and 15.1 vs. 5.1%, p = 0.012). Radiological disease control was better in the TACE + SBRT group (98 vs. 56.7%). Risk of severe toxicity was uncommon in both treatment arms. TACE + SBRT was an independent good prognostic factor for OS and PFS in multivariate analysis, whereas AFP>200 ng/ml, large tumor and multiple tumors predicted worse OS.

CONCLUSION

TACE + SBRT is safe and results in better survivals in nonresectable HCC patients.

Combined stereotactic body radiotherapy and trans-arterial chemoembolization as initial treatment in BCLC stage B-C hepatocellular carcinoma

PURPOSE

We retrospectively evaluated the efficacy and safety of stereotactic body radiotherapy (SBRT) combined with trans-arterial chemoembolization (TACE) as initial therapy in Barcelona Clinic Liver Cancer (BCLC) system stage B-C hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Seventy-two patients received a single dose of TACE followed by SBRT 4 weeks later. All patients had tumor sizes ≥5 cm, at least 700 ml of disease-free liver, Child-Pugh (CP) score ≤ B7 and tumor nodules ≤5. SBRT dose, ranging from 6 × 5-8 Gy or 5-10 × 4 Gy, was individualized according to normal tissue constraints. No subsequent scheduled treatment was delivered unless disease progression was observed. Local control (LC), overall survival (OS), progression-free survival (PFS), response rate (RR), and toxicity were evaluated.

RESULTS

The patients' characteristics were: median age 60 years (range 28-87 years); CP score A/B (n = 68/4); BCLC stage B/C (n = 51/21); solitary/multifocal (n = 37/35); portal vein invasion (n = 18). The median tumor size and GTV were 11.2 cm (range 5.0-23.6 cm) and 751 cm³ (range 41-4009 cm³), respectively. The median equivalent dose in 2 Gy per fraction (EQD2, α/β = 10) was 37.3 Gy2 (range, 28-72 Gy2). The median follow-up time was 16.8 months (range, 3-96 months). The objective RR was 68% and the 1‑year LC rate was 93.6% (95% CI, 87.6-100%). The median OS was 19.8 months (95% CI, 11.6-30.6 months). SBRT-related grade 3 or higher adverse gastrointestinal events and treatment-related death occurred in three (2.8%) and one patient (1.4%) respectively. No patient developed classical radiation-induced liver injury.

CONCLUSION

Our experience suggests that combined TACE and SBRT can be a safe and effective initial therapy for BCLC stage B-C HCC with appropriate patient selection. Further prospective trials are warranted.

Single fraction computed tomography-guided high-dose-rate brachytherapy or stereotactic body radiotherapy for primary and metastatic lung tumors?

PURPOSE

To provide a pilot dosimetric study of computed tomography (CT)-guided high-dose-rate (HDR) brachytherapy (BRT) and stereotactic body radiotherapy (SBRT) for primary and metastatic lung lesions.

MATERIAL AND METHODS

For nine lung primary and metastasis patients, 3D image-based BRT plan using a single virtual catheter was planned for 34 Gy in single fraction to the gross tumor volume (GTV) + 3 mm margin to account for tumor deformation. These plans were compared to margin-based (MB-) and robustness optimized (RO-) SBRT, assuming the same tumor deformation under real-time tumor tracking. Consistent dose calculation was ensured for both BRT and SBRT plans using the same class of collapsed cone convolution superposition algorithm. Plan quality metrics were compared by Friedman tests and Wilcoxon t-tests.

RESULTS AND CONCLUSIONS

Brachytherapy plans showed significant higher GTV mean dose compared to MB- and RO-SBRT (122.2 Gy vs. 50.4 and 44.7 Gy, p < 0.05), and better dose gradient index (R50) = 2.9 vs. 4.3 and 8.4 for MB- and RO-SBRT, respectively. Dose constraints per the RTOG 0915 protocol were achieved for all critical organs except chest wall in BRT. All other dose-volume histograms (DVH) metrics are comparable between BRT and SBRT. Treatment delivery time of BRT and SBRT plans significantly increased and decreased with increasing GTV size, respectively. SBRT using advanced MLC tracking technique and non-coplanar VMAT can achieve comparable dosimetric quality to HDR BRT. Whether or not, the significantly higher GTV dose can increase killing of radioresistant tumor cells and offset the effect of tumor reoxygenation in single fraction BRT, requires further clinical investigation.

Management of Nasopharyngeal Carcinoma: Is Adjuvant Therapy Needed?

Nasopharyngeal carcinoma of the undifferentiated histologic subtype is endemic and prevalent in southeast Asia. The dramatic improvement of treatment outcomes and overall prognosis during the past few decades has been attributed to advances in disease screening and diagnosis, diagnostic imaging, radiotherapy techniques, use of combination systemic therapy, and dedicated clinical and biomarker surveillance. The current practice of treating patients with advanced locoregional disease using cisplatin concurrent with conventional fractionated radiotherapy, followed by adjuvant cisplatin and fluorouracil, was established in 1998 when the landmark Intergroup-0099 Study demonstrated a survival benefit with the addition of systemic therapy.

There is little doubt regarding the need for concurrent chemotherapy, but there has been uncertainty about the magnitude of the benefit attributed to the adjuvant phase. Furthermore, instead of one-size-fits-all recommendations, it will be ideal if we can tailor adjuvant therapy to high-risk patients only to avoid unnecessary toxicities. In addition, recent evidence suggests that induction chemotherapy before concurrent chemoradiation can achieve better outcomes, especially in distant control, even in the modern era of intensity-modulated radiation therapy. This article provides a comprehensive review of key literature on the current management of locoregionally advanced nasopharyngeal carcinoma and highlights future research directions to unravel these controversies.

Comparison of platelet-albumin-bilirubin (PALBI), albumin-bilirubin (ALBI), and child-pugh (CP) score for predicting of survival in advanced hcc patients receiving radiotherapy (RT)

Purpose

This work evaluated the prognostic performance of Child-Pugh (CP), albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) scores in hepatocellular carcinoma (HCC) patients undergoing radiotherapy (RT).

Results

The study included 174 consecutive patients with 63% at CP A5 (n = 110) and 34% at CP A6 (n = 64). The median ALBI score was −2.39 (range: −3.61 to −1.41) with 34.5% at grade A1 (n = 60) and 65.5% at grade A2 (n = 114). The median PALBI score was −2.39 (range −3.39 to −1.24) with 33.3% at grade 1 (n = 58), 41.4% at grade 2 (n = 72) and 25.3% at grade 3 (n = 44). With a median follow-up of 21.7 months, the median OS of the entire cohort was 22.2 months. OS was significantly associated with the PALBI grade (p = 0.002) and for the ALBI grade (p = 0.00495), but not for the CP score (p = 0.46). The PALBI grade has a significantly higher AUC compared than the ALBI grade or CP scores in predicting OS. The PALBI grade was predictive of CP score decline ≥2 (20% grade 3 vs. 5.3% grade 1/2 p = 0.05) but the ALBI and CP scores were not.

Conclusion

Among CP A HCC patients receiving radiotherapy, the PALBI and ALBI grade maybe a better prognostic tool than the CP score. The role of PALBI in predicting liver toxicity warranted further exploration.

Methods

We retrospectively reviewed HCC patients treated with individualized hypo-fractionated radiotherapy (IHRT) using stereotactic technique from 2006 to 2015. We collected CP, ALBI and PALBI scores prior to treatment and analyzed their correlation with overall survival (OS) and liver toxicity.

Adjuvant S-1 chemotherapy after curative resection of gastric cancer in Chinese patients: assessment of treatment tolerability and associated risk factors

INTRODUCTION

The use of adjuvant chemotherapy with S-1 (tegafur, gimeracil, and oteracil potassium) has been shown to improve the outcome of patients with gastric cancer. There are limited data on the tolerability of S-1 in Chinese patients. In this multicentre retrospective study, we assessed the toxicity profile in local patients.

METHODS

Patients with stage II-IIIC gastric adenocarcinoma who had undergone curative resection and who had received S-1 adjuvant chemotherapy were included in the study. Patient demographics, tumour characteristics, chemotherapy records, as well as biochemical, haematological, and other toxicity profiles were extracted from medical charts. Potential factors associated with grade 2-4 toxicities were identified.

RESULTS

Adjuvant S-1 was administered to 30 patients. Overall, 19 (63%) patients completed eight cycles. The most common grade 3-4 adverse events included neutropaenia (10%), anaemia (6.7%), septic episode (16.7%), diarrhoea (6.7%), hyperbilirubinaemia (6.7%), and syncope (6.7%). Dose reductions were made in 22 (73.3%) patients and 12 (40.0%) patients had dose delays. Univariate analyses showed that patients who underwent total gastrectomy were more likely to experience adverse haematological events (P=0.034). Patients with nodal involvement were more likely to report adverse non-haematological events (P=0.031). Patients with a history of regular alcohol intake were more likely to have earlier treatment withdrawal (P=0.044). Lower body weight (P=0.007) and lower body surface area (P=0.017) were associated with dose interruptions.

CONCLUSIONS

The tolerability of adjuvant S-1 in our patient population was similar to that in other Asian patient populations. The awareness of S-1-related toxicities and increasing knowledge of potential associated factors may enable optimisation of S-1 therapy.

Randomized phase II study of the x-linked inhibitor of apoptosis (XIAP) antisense AEG35156 in combination with sorafenib in patients with advanced hepatocellular carcinoma (HCC)

4105

Background: XIAP inhibits caspases which are proteases responsible for apoptotic cell death. It is highly expressed in HCC. AEG35156 is a second generation antisense oligonucleotide targeting XIAP mRNA, thus lowers the apoptotic threshold of cancer cells. It also accumulates in the liver. This study is designed to assess the added benefit of combining AEG35156 with sorafenib. Methods: Patients with histologically or clinically diagnosed (AASLD criteria) HCC who had failed or were unsuitable for resection or ablative therapies were randomized (2:1) to receive either weekly injection of AEG35156 300mg in combination with sorefanib 400mg BID or sorefanib alone. The primary end point was progression-free survival (PFS). Other endpoints were overall survival (OS), response rates and safety. Results: 51 patients were recruited. 48 patents were evaluable. There were 31 patients in the combination arm and 17 in the control arm. The median age was 60. 88% of patients were male. 81% of patients were hepatitis B carrier. 90% of patients belong to Child-Pugh class A. The median follow-up was 16.2 months. The PFS for the combination arm was 4.0 months (95% CI: 1.2-4.1) and 2.6 months for control arm. The OS for the combination arm was 6.5 months (95% CI: 3.9-11.5) and 5.4 months for the control arm. There were 3 partial responders (Choi’s criteria) in the combination arm (10%, 95% CI: 3-27%) and none (0%) in the control arm. Patients who had the study treatment interrupted (PFS 4.0, 95% CI: 2.4-5.4) or had dose modification (PFS 4.45, 95% CI: 1.0-6.5) according to protocol did significantly better than those who had no dose reduction (PFS 1.2, 95% CI: 1.2-4.0) and those in the control arm (PFS 2.6, 95% CI: 1.2-5.4). This also applies to OS. Regarding toxicities, there were one AEG35156 related serious adverse event (SAE) of hypersensitivity and two sorafenib related gastrointestinal SAE. Conclusions: AEG35156 in combination with Sorafenib was well tolerated in patients with advanced HCC. Dose reduced AEG35156 in combination with sorafenib have shown more activity than sorafenib alone and warrants further investigation.

Klebsiella meningitis mimicking clinical deterioration from hemorrhage of a complex posterior fossa arteriovenous malformation

We report a case of a 33-year-old male with a history of complex posterior fossa arteriovenous malformation (AVM) with partial resection done in China; at follow-up in our unit, he presented with a 1-day history of acute deterioration of consciousness level after minor head injury. The clinical and radiologic features were compatible with spontaneous hemorrhage from the AVM, and the patient died 1 day after admission. However, postmortem examination revealed the direct cause of death was due to Klebsiella meningitis. The clinical catch is highlighted, and the importance of early and prompt detection of this condition is emphasized.

Parenteral nutrition support after bone marrow transplantation: comparison of total and partial parenteral nutrition during the early posttransplantation period

OBJECTIVE

Bone marrow transplantation (BMT) usually is indicated if the patient's malignant disease involves the marrow or if hazard to the normal marrow is the limiting factor in the aggressive treatment of disease. The success of BMT depends on a complete team with all the resources needed to ensure optimal results. Aggressive nutrition support after BMT is very important. Adequate parenteral nutrition, total (TPN) or partial, followed by enteral nutrition according to the patient's gastrointestinal function is the important principle.

METHODS

Between 1996 and 2000, 60 patients, 46 male and 14 female, received BMT in Chang Gung Memorial Hospital. Their ages ranged from 6 to 54 y. Standard TPN was used in 40 patients after BMT, and partial parenteral nutrition was used in the remaining 20 patients. TPN was enriched with branched-chain amino acids (BCAA) when the patient's liver functions were impaired, and cyclic TPN was shifted when the patient's liver functions persistently deteriorated.

RESULTS

Most patients improved their nutrition status and increased their body weights, especially those receiving TPN. The patients receiving partial parenteral nutrition decreased their visceral proteins significantly during the course of parenteral nutrition. The BCAA-TPN can maintain a patient's visceral protein better than standard TPN. Only two patients expired because of graft rejection and sepsis; their body weights and nutrition status showed deterioration despite aggressive nutrition support.

CONCLUSIONS

We conclude that the nutrition support for patients with BMT is related to the success of marrow transplantation. Parenteral nutrition support, especially with TPN, is important because of frequent gastrointestinal dysfunction during the posttransplantational period, and it is better at maintaining the nutrition status and body weights of patients after BMT. An oral diet can be resumed after the patient's gastrointestinal function has improved and it can be tolerated.

Controlled Growth of Gold Nanoparticles in Aerosol-OT/Sorbitan Monooleate/Isooctane Mixed Reverse Micelles

Stable anisotropic gold nanoparticles were prepared by the reduction of tetrachloroauric acid with hydrazine in mixed reverse micelles formed with anionic surfactant Aerosol-OT and nonionic surfactant sorbitan monooleate (Span80) in isooctane. It was found that the Span80 serves not only as a structure modifier but also as a stabilizer for Au particles, to prevent their further growth and precipitation. The control of particle size, shape, and degree of dispersion was achieved by varying the process variables, such as molar ratio of reduction agent to metal salt, size of water droplets (omega(o)), concentration of metal salt, and sequence of addition of metal salt into the mixed reverse micelles. When the HAuCl(4) was injected directly into the mixed reversed micelles containing hydrazine, nonspherical gold nanoparticles, such as rods and cubes, were obtained at the molar ratio of hydrazine to HAuCl(4) of less than 1.0. The nonspherical Au particles were preferably formed at larger omega(o) value and lower gold salt loading. By the analyses of high-resolution electron microscope, electron diffraction pattern, and energy-dispersive X-ray analysis (EDX), the resultant particles have been found to be pure gold of face-centered cubic structure. Copyright 2000 Academic Press.

Induction of CD8 T cells by vaccination with recombinant adenovirus expressing human papillomavirus type 16 E5 gene reduces tumor growth

The potential of the E5 protein as a tumor vaccine candidate has not been explored yet. In this study, we evaluate the human papillomavirus type 16 (HPV-16) E5 protein delivered by an adenovirus vector as a tumor vaccine for cervical lesions. The results demonstrate that a single intramuscular injection of a recombinant adenovirus carrying the HPV-16 E5 gene into syngeneic animals can reduce the growth of tumors which contain E5 gene expression. Moreover, the E5 vaccine-induced tumor protection occurs through CD8 T cells but not through CD4 T cells in in vitro assays. In addition, our studies using knockout mice with distinct T-cell deficiencies confirm that cytotoxic T-lymphocyte-induced tumor protection is CD8 dependent but CD4 independent. Hence, HPV-16 E5 can be regarded as a tumor rejection antigen.

The hepatoprotective effects of Solanum alatum Moench. on acetaminophen-induced hepatotoxicity in mice

Solanum alatum Moench. has been shown to have a protective effect against carbon tetrachloride (CCl4)-induced liver injury. Solanum alatum treatment (100 mg/kg, p.o.) decreased the elevation of serum alanine aminotransferase (ALT; GPT) and aspartate aminotransferase (AST; GOT) induced by acetaminophen (paracetamol) (600 mg/kg, i.p.) administration. It also decreased the extent of visible necrosis in liver tissue. In addition, Solanum alatum treatment restored hepatic glutathione (GSH) depletion induced by acetaminophen (600 mg/kg, i.p.) administration. Microsomal enzyme levels such as P-450, reductase, and aniline hydroxylation enzyme were also restored to normal levels after Solanum alatum administration. The hepatoprotective mechanism may function through direct binding with acetaminophen toxic metabolites, decreasing the attraction of acetaminophen metabolites for other cellular GSH or thiol protein. Additionally, Solanum alatum treatment increased the concentration of hepatic GSH and maintained a high level activity of GSTase, which led to acceleration of the excretion of toxic acetaminophen metabolites.

The influence of propolis ethanol extract on liver microsomal enzymes and glutathione after chronic alcohol administration

Propolis designates a series of gums, resins and balms of viscous consistency, which are gathered by honeybees from certain parts, mainly the buds and barks of plants, especially those found on coniferous trees. Bees bring propolis back to the hive, where it is modified and mixed with other substances including the bees' own wax and salivary secretions. In this study, the influences of propolis ethanol extract on chronic alcohol induced liver microsomal enzyme changes were investigated. Three grams of alcohol was added to rats' daily diet for four weeks to induce chronic alcohol liver injuries, and two different doses of propolis ethanol extract were p.o. administrated three times per day on the 28th, 29th, and 30th day. During the period of propolis administration, the ethanol diet was continued. After sacrifice, the rat livers were excised for assay of microsomal enzymes activity, glutathione (GSH) concentration, glutathione-S-transferase (GSTase) and gamma-glutamylcysteine synthetase (gamma-GCSase) activity. It was found that 30 mg/kg of propolis ethanol extract significantly prevented the elevations of total cytochrome P-450 enzymes, NADPH-dependent cytochrome C reductase, aniline hydroxylation, 7-ethoxyresorufin hydroxylation (7-ERH), 7-penthoxyresorufin hydroxylation (7-PRH), and lipid peroxidation induced by chronic ethanol administration. Additionally, propolis ethanol extract (100 mg/kg) also induced GSTase and gamma-GCSase activities and decreased glutathione levels in the liver.

Estimation of duration of separation, widowhood, and family life cycle

This is the second of two reports on a study of the durations related to marriage. Divorce and death of one's spouse, the main causes of dissolution of marriage, are two of the most important events in a person's life. In the United States in 1994, 30.7 million, or 16.2%, of the adult population were either divorced or widowed. Among the widowed, the female to male ratio was 5 to 1! In this paper duration of separation due to divorce and duration of widowhood are the main variables under study. Algebraic formulas are derived and computer programs are written for estimating these durations for husbands and wives, and for living couples of any age. Relations with the duration of marriage, the expectation of life, and the family life cycle are also presented.

Effects of equal and unequal reinforcer duration during functional analysis

In the functional analysis described by Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994), reinforcer duration varied across conditions (e.g., brief attention vs. 30 s of escape); this may result in unequal exposure to the establishing operations for aberrant behavior. In this study, we compared the effects of unequal and equal reinforcer duration during a functional analysis. The results showed that reinforcer duration affects the rate of aberrant behavior and may potentially alter functional analysis interpretation.

Action of lipolytical enzymes in biphasic organic-aqueous systems: dynamics of the irreversible Michaelis-Menten reaction

Through simple model analysis, the mass action kinetic model for lipolytic enzymes in biphasic aqueous-organic systems can be simplified using the quasi-steady state assumption (or the quasi-equilibrium state assumption) for the adsorbed enzyme E* or the enzyme-substrate complex E*S. Some parameter combinations leading to the above assumptions are derived confirmed by full numerical integration of the whole enzymatic process. The results may be classified into three categories: (1) the quasi-equilibrium state assumption for E*, (2) the quasi-steady state assumption for E*, and (3) the quasi-steady state assumption for E*S. Further simplification for both E* and E*S is also discussed.

Early diagnosis of a vein of Galen aneurysm: report of a case

Congenital vascular malformation with an aneurysm of the vein of Galen is rarely seen, particularly in the prenatal period. With the advancement of diagnostic techniques such as ultrasonography, we were able to detect a case prenatally and to diagnose it postnatally.

A two-state recurrent stochastic model with time-dependent transition rates

The two-state recurrent stochastic model with time-independent transition rates is generalized to a model with time-dependent transition rates. The rates can be any general function of external time, that is, any general function of the calendar time in which the process unfolds. Formulas for the state transition probabilities, the proportion of individuals in a particular state at time t, the distribution function, and the expectation of the number of individuals in a particular state at time t are derived.

A true rate of population growth--Lotka's intrinsic rate of natural increase revisited

In this paper, Lotka's intrinsic rate of current population growth is evaluated. A new method of computing the net reproduction rate and a new rate of population growth are proposed. The proposed rate is the rate of growth of the female population per woman per year. The rate is positive, equal to zero, or negative as a population is increasing, remaining stationary, or decreasing. The rate for the 1987 U.S. white female population was R = -0.0037. This means that the white population was decreasing in 1987 and was losing 3.7 females for every 1000 women per year.

Enzyme loading in a solid support with nonuniform pore size distribution

The concept of pore size distribution is incorporated into the Clark model of enzyme immobilization in the present study. This refined model predicted that in the case of small harmonic pore radius with the same surface area and porosity of the support, more enzyme could be loaded in a support with nonuniform pores than that with uniform pores. In comparing the enzyme loading efficiency of the support with two different pore size distributions, the one with Gaussian distribution had the greater amount of enzyme immobilized than the other one with Rajagopalan's distribution. Furthermore, more enzyme could be loaded in a support with wider Gaussian pore size distribution than that with narrower distribution. The immobilized enzyme profile in the solid support with pore size distribution displayed a stepwise pattern which differed appreciably from the sigmoidal profile predicted for the support with uniform pore size. This stepwise enzyme distribution profile became sigmoidal with decreasing h(T) or increasing k. The new model could be used for designing protocols for an enzyme immobilization process.

A survival model and estimation of time to tumor

In this paper we introduce a stochastic model of survival distribution, where the mortality intensity is a function of the accumulated effect of an individual's continuous exposure to toxic material in the environment (absorbing coefficient) and his biological reaction to the toxin absorbed (discharging coefficient). Formulas for the density function, the distribution function, and the expectation of lifetime are presented. The paper also includes special cases where there is a change in exposure level or exposure is discontinued or exposure is discrete in time. The model is then applied to the NCTR's serial sacrifice experimental study on mice fed 2-AAF, including some mice whose feeding was discontinued. The random variable here is the time to tumor. The chi-square test shows a good fit of the model to the data (P = 0.365). In addition to the parameters and their standard errors, estimates are computed for the expectation, variance, and percentiles of time to tumor, and for the age-specific cancer incidence rates. Confidence intervals for the parameters are also given.

Phospholipids and fatty acid profile of brain synaptosomal membrane from normotensive and hypertensive rats

1. The main synaptosomal membrane phospholipids and their acyl group profiles, from 3-4 month-old spontaneously hypertensive rats (SHR), were compared with those of age-matched normotensive Wistar Kyoto (WKY) rats. 2. The contents of the main or total phospholipids were not found to be significantly different between these two groups. It was also true for the membrane cholesterol contents in these two groups. 3. The acyl groups of the main phospholipids from hypertensive rats were significantly higher in the saturated fatty acids: such as palmitic acid or stearic acid, and lower in polyunsaturated fatty acids: such as undecylenic acid or docosahexaenoic acid, when compared to the corresponding normotensive controls. 4. The differences in the acyl group profile of the brain membrane phospholipids of the hypertensive rats seem to reflect an abnormality in the genetically related lipolytic process.