Joint effect of defocus blur and spatial attention

Defocus blur and spatial attention both act on our ability to see clearly over time. However, it is currently unknown how these two factors interact because studies on spatial resolution only focused on the separate effects of attention and defocus blurs. In this study, eleven participants performed a resolution acuity task along the diagonal 135˚/315˚ with horizontal, at 8˚ eccentricity for clear and blurred Landolt C images under various manipulations of covert endogenous attention. All the conditions were interleaved and viewed binocularly on a visual display. We observed that attention not just improves the resolution of clear stimuli, but also modulates the resolution of defocused stimuli for compensating the loss of resolution caused by retinal blur. Our results show, however, that as the degree of attention decreases, the differences between clear and blurred images largely diminish, thus limiting the benefit of an image quality enhancement. It also appeared that attention tends to enhance the resolution of clear targets more than blurred targets, suggesting potential variations in the gain of vision correction with the level of attention. This demonstrates that the interaction between spatial attention and defocus blur can play a role in the way we see things. In view of these findings, the development of adaptive interventions, which adjust the eye's defocus to attention, may hold promise.

The Application of Non-linear Flow Resistance in Cerebral Artery: Compared with Windkessel Model based on Genetic Algorithm

Continuous blood pressure is measured from various extracranial body sites, with difference in amplitude and phase with intracranial blood pressure. Consequent influences on the accuracy of Windkessel model need further investigation. Between blood pressure and intracranial flow rate, a model with non-linear flow resistance (R-DT) was proposed and compared with the 3-element Windkessel (RCR) model. From the measured blood flow velocity in middle cerebral artery, the blood pressure was estimated by R-DT and RCR models respectively. The parameters in the models were optimized by genetic algorithm. The accuracies of R-DT and RCR models were compared based on their estimation errors to the measured blood pressure. The capacitance element in RCR model indicated limited ability to take the time shift into account. Compared with RCR model, R-DT model had less error (averaged relative error: 5.19% and 2.49% for RCR and RDT models). The non-linear flow resistance was applicable in simulating cerebral arteries.

Translesional pressure gradient and leptomeningeal collateral status in symptomatic middle cerebral artery stenosis

BACKGROUND AND PURPOSE

Leptomeningeal collateral (LMC) status governs the prognosis of large artery occlusive stroke, although factors determining LMC status are not fully elucidated. The aim was to investigate metrics affecting LMC status in such patients by using computational fluid dynamics (CFD) models based on computed tomography angiography (CTA).

METHODS

In this cross-sectional study, patients with recent ischaemic stroke or transient ischaemic attack attributed to atherosclerotic M1 middle cerebral artery (MCA) stenosis (50%-99%) were recruited. Demographic, clinical and imaging data of these patients were collected. Ipsilesional LMC status was graded as good or poor by assessing the laterality of anterior and posterior cerebral arteries in CTA. A CFD model based on CTA was constructed to reflect focal hemodynamics in the distal internal carotid artery, M1 MCA and A1 anterior cerebral artery. Pressure gradients were calculated across culprit MCA stenotic lesions in CFD models. Predictors for good LMC status were sought in univariate and multivariate analyses.

RESULTS

Amongst the 85 patients enrolled (mean age 61.5 ± 10.9 years), 38 (44.7%) had good ipsilesional LMC status. The mean pressure gradient across MCA lesions was 14.8 ± 18.1 mmHg. Advanced age (P = 0.030) and a larger translesional pressure gradient (P = 0.029) independently predicted good LMCs. A lower fasting blood glucose level also showed a trend for good LMCs (P = 0.058).

CONCLUSIONS

Our study suggested a correlation between translesional pressure gradient and maturation of LMCs in intracranial atherosclerotic disease. Further studies with more exquisite and dynamic monitoring of cerebral hemodynamics and LMC evolution are needed to verify the current findings.

Good collateral circulation predicts favorable outcomes in intravenous thrombolysis: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Baseline collateral status has been correlated with outcomes of acute ischaemic stroke patients receiving intravenous thrombolysis (IVT) in previous studies. We carried out the current systematic review and meta-analysis to synthesize currently available evidence regarding such correlations.

METHODS

Full-text articles published since 2000 were retrieved and screened. The overall effect sizes of good versus poor collateral status over a series of outcomes and certain baseline features were estimated by random-effects models and presented in risk ratios (RRs) or mean differences.

RESULTS

Overall, 28 (3057 patients) and 14 (1584 patients) studies were included in qualitative and quantitative synthesis, respectively. Compared with poor pre-treatment collateral status, good collaterals showed a beneficial effect over the primary outcome of a favorable functional outcome at 3 or 6 months [RR, 2.45; 95% confidence interval, 1.94-3.09; P < 0.001] in acute ischaemic stroke patients receiving IVT treatment. However, such an effect tended to be different between studies with prescribed time windows of 3, 4.5 and > 4.5 h (up to 7 h), with the RRs being 2.21, 2.48 and 5.00, respectively (I²  = 53%). Good pre-treatment collaterals were also associated with a smaller infarct size at baseline, and a lower rate of symptomatic intracranial hemorrhage and a higher rate of neurological improvement early after IVT treatment.

CONCLUSIONS

The present study has demonstrated the prognostic value of baseline collateral circulation for outcomes of acute ischaemic stroke patients receiving intravenous reperfusion therapies, studied with different time windows of up to 7 h after ictus for IVT therapy.

A design of a DICOM-RT-based tool box for nonrigid 4D dose calculation

The study was aimed to introduce a design of a DICOM-RT-based tool box to facilitate 4D dose calculation based on deformable voxel-dose registration. The computational structure and the calculation algorithm of the tool box were explicitly discussed in the study. The tool box was written in MATLAB in conjunction with CERR. It consists of five main functions which allow a) importation of DICOM-RT-based 3D dose plan, b) deformable image registration, c) tracking voxel doses along breathing cycle, d) presentation of temporal dose distribution at different time phase, and e) derivation of 4D dose. The efficacy of using the tool box for clinical application had been verified with nine clinical cases on retrospective-study basis. The logistic and the robustness of the tool box were tested with 27 applications and the results were shown successful with no computational errors encountered. In the study, the accumulated dose coverage as a function of planning CT taken at end-inhale, end-exhale, and mean tumor position were assessed. The results indicated that the majority of the cases (67%) achieved maximum target coverage, while the planning CT was taken at the temporal mean tumor position and 56% at the end-exhale position. The comparable results to the literature imply that the studied tool box can be reliable for 4D dose calculation. The authors suggest that, with proper application, 4D dose calculation using deformable registration can provide better dose evaluation for treatment with moving target.

Abstract WP121: An Evaluation of Hemodynamics Across Intracranial Steno-occlusive Lesions by Computational Fluid Dynamics

Introduction: Intracranial atherosclerotic steno-occlusive disease (ICAS) is a major cause of stroke worldwide and portends a high risk of recurrence. Computational fluid dynamics (CFD) is a novel technique developed to solve and analyze the dynamic effects of fluid flow. We aimed to analyse hemodynamics across ICAS using CFD on processed CTA images and explore the correlation between the degree of arterial stenosis and hemodynamic flow status.

Methods: We recruited patients with symptomatic ICAS from Acute Stroke Unit, Prince of Wales Hospital. All patients received CTA and DSA as vascular workup. Using CFD analysis of processed CTA images, we first defined the hemodynamic parameters, including pressure difference, pressure ratio, pressure gradient, shear strain rate ratio (SSR), wall shear stress (WSS) ratio and velocity ratio, across the stenosed vessels, and then we correlated the severity of stenosis as defined by DSA, with these parameters.

Results: Among the 53 recruited patients (mean age 62.9 years, 69.8% males), 45 (85%) had lesions in the anterior circulation. The severity of stenosis showed a weak-to-moderate correlation with pressure difference (rs=0.392, p=0.004), pressure ratio (rs=-0.429, p=0.001) and pressure gradient (rs=0.419, p=0.002). There was no significant correlation between the severity of stenosis with SSR ratio, WSS ratio and velocity ratio. Among patients with anterior circulation stroke or TIA, the severity of stenosis showed a weak to moderate correlation with pressure difference (rs=0.381, p=0.01), pressure ratio (rs=-0.426, p=0.004) and pressure gradient (rs=0.407, p=0.005). For patients with posterior circulation stroke or TIA, the severity of stenosis was strongly correlated with pressure difference (rs=0.714, p=0.047) and pressure ratio (rs=-0.714, p=0.047); and very strongly correlated with velocity ratio (rs=0.833, p=0.01).

Conclusions: The severity of ICAS showed only weak-to-moderate correlation with hemodynamic parameters across the culprit lesion. Thus, risk stratification and treatment based solely on stenotic severity may be inadequate. Our findings may guide further research in estimating stroke risks and selection of high-risk patients who may benefit from adjunctive treatments.

Indications for and pregnancy outcomes of cervical cerclage: 11-year comparison of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage

OBJECTIVES

To review and compare pregnancy outcomes of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage.

DESIGN

Case series with internal comparison.

SETTING

A regional obstetric unit in Hong Kong.

PATIENTS

Women undergoing cervical cerclage at Kwong Wah Hospital between 1 January 2001 and 31 December 2011.

INTERVENTIONS

Cervical cerclage.

MAIN OUTCOME MEASURES

Pregnancy outcomes including miscarriage, gestational age at delivery, birth weight, and duration of pregnancy prolongation.

RESULTS

Overall, 47 patients were included. Nine (19.1%) pregnancies resulted in miscarriage. The median gestational age at delivery was 35.7 weeks. Among the 23 patients who had history-indicated cerclage, only four (17.4%) had three or more previous second-trimester miscarriages or preterm deliveries. Among the 15 patients who had ultrasound-indicated cerclage, preoperative cervical length of ≤1.5 cm was associated with shorter prolongation of pregnancy, compared with that of >1.5 cm (median, 12.1 vs 18.4 weeks; P=0.009). Among the nine women who had rescue cerclage, those who underwent the procedure before 20 weeks of gestation delivered earlier than those underwent cerclage later (median, 22.5 vs 34.1 weeks; P=0.048).

CONCLUSIONS

Patients eligible for the Royal College of Obstetricians and Gynaecologists-recommended history-indicated cerclage remain few. The majority of patients may benefit from serial ultrasound monitoring of cervical length with or without ultrasound-indicated cerclage.

Adding computed tomography and transcranial Doppler findings to the ABCD2 score to predict long-term risk of stroke after transient ischaemic attack or minor stroke

BACKGROUND AND PURPOSE

The ABCD(2) score can predict the early risk of stroke after transient ischaemic attack or minor stroke. However, there is no simple and practical assessment method for the long-term risks. Computed tomography (CT) and transcranial Doppler (TCD) findings were added to the ABCD(2) score to build an ABCD(2) L(2) score and whether the new scoring system could improve the predictive value of the ABCD(2) score for the long-term risk of stroke was determined.

METHODS

From January 2004 to December 2005, all patients with a definite diagnosis of transient ischaemic attack or minor stroke at the Prince of Wales Hospital were consecutively enrolled and followed up until August 2008. CT and TCD were performed. The areas under the curve were used to quantify the ABCD(2) and ABCD(2) L(2) scores and related items.

RESULTS

All 481 patients completed the follow-up. The shortest follow-up time was 0.17 months (until death), the longest follow-up time was 55.60 months and the mean follow-up time was 40.3 ± 11.0 months. In total, 277 (57.6%) patients showed lesions on CT scans and 195 (40.6%) patients were found with intracranial large artery atherosclerosis. Further strokes occurred in 74 (15.4%) patients, including four (0.83%) patients who died of ischaemic stroke during the follow-up period. The area under the curve increased from 0.650 (0.586-0.715) for the ABCD(2) score to 0.700 (0.637-0.764) for the ABCD(2) L(2) score.

CONCLUSION

Adding CT and TCD results to the ABCD(2) score to increase its predictability for long-term risk of stroke recurrence might be a meaningful exploration.

Use of methylphenidate for the management of fatigue in Chinese patients with cancer

REASON FOR THE STUDY: Studies on methylphenidate for cancer-related fatigue showed conflicting results. This prospective study aims to determine whether methylphenidate is useful for relieving fatigue in Chinese patients with cancer. Chinese Version of Brief Fatigue Inventory (BFI-C) was administered on days 1, 8, and 29. Methylphenidate dose on day 1 was 5 mg daily then adjusted after day 8 according to response and side effects tolerance.

MAIN FINDINGS

Only 48% of the 25 recruited patients were on methylphenidate by day 29. Overall, no significant improvement in fatigue level was observed after methylphenidate, though benefits were shown in subgroups with age ≤ 65 and higher baseline BFI-C values.

PRINCIPAL CONCLUSIONS

Methylphenidate may be useful for management of cancer-related fatigue in selected Chinese patients.

Genetic predisposition of white matter infarction with protein S deficiency and R355C mutation

BACKGROUND

The association between protein S deficiency (PSD) and ischemic stroke is controversial and warrants further investigation.

METHODS

We conducted a genotype and MRI correlation study in a Chinese family in which hereditary PSD cosegregated with premature ischemic strokes. Six out of 11 family members inherited PSD type III in an autosomal dominant manner.

RESULTS

Among all PSD members, a novel missense mutation 1063C→T in exon 10 of protein S alpha (PROS1) was identified, which encoded a substitution of arginine to cysteine at position 355 (R355C) in the first globular domain of laminin A of protein S. Wild-type PROS1 sequences were retained in non-PSD members. MRI detected deep white matter infarctions predominantly distributed in the borderzone regions. The infarct topography was homogeneous in all adult mutant carriers. By contrast, cerebral infarction was absent in nonmutant carriers. Extensive investigation in the family did not reveal any confounding stroke risk. Haplotype analysis with high-density single nucleotide polymorphism markers revealed a 6.1-Mb minimally rearranged region (rs12494685 to rs1598240) in 3q11.2, lod = 3.0. Among the 7 annotated genes in this region, PROS1 is known to be associated with thrombotic disorders. MRI screening in an additional 10 PSD families without R355C showed no cerebral infarction.

CONCLUSIONS

PROS1 R355C mutation cosegregated with PSD type III and premature white matter infarctions in the index family. The findings substantiate an association between PSD and stroke. Study of the mechanism underlying this association may improve our understanding of premature cryptogenic white matter infarction.

An expedited stroke triage pathway: the key to shortening the door-to-needle time in delivery of thrombolysis

OBJECTIVES

To assess time management of stroke thrombolysis triage and functional outcomes in patients receiving recombinant tissue plasminogen activator for hyperacute stroke, and identify bottlenecks in delivery of the treatment.

DESIGN

Prospective study.

SETTING

A university teaching hospital in Hong Kong.

PATIENTS

Patients with suspected hyperacute stroke referred to the stroke thrombolysis team during October 2008 to September 2009.

MAIN OUTCOME MEASURES

Time performance records including door-to-stroke team, door-to-needle, and onset-to-thrombolysis times. Functional outcomes by modified Rankin Scale score at 3 months, and thrombolysis-related complications including haemorrhagic transformations and mortality.

RESULTS

During the 12-month period, 95 thrombolysis calls were received; recombinant tissue plasminogen activator was given intravenously to 17 (18%) of the patients and intra-arterially to 11 (12%). The mean (standard deviation) door-to-stroke team and the door-to-needle times for intravenous recombinant tissue plasminogen activator patients were 33 (25) and 80 (25) minutes, respectively; both were about 20 minutes longer than that recommended by the National Institute of Neurological Disorders and Stroke. The mean National Institute of Health Stroke Scale score for patients received intravenous recombinant tissue plasminogen activator was 16 (standard deviation, 7). The mean (standard deviation) onset-to-treatment time was 144 (42) minutes. Nine (53%) patients who received intravenous recombinant tissue plasminogen activator achieved favourable outcomes at 3 months, with a modified Rankin Scale score of 0 to 1. Symptomatic haemorrhage and mortality occurred in one (6%) patient.

CONCLUSION

A dedicated stroke triage pathway is essential to ensure efficient and safe delivery of thrombolysis therapy. Improvements in door-to-stroke team time through integration with emergency medicine staff and neuroradiologists may improve thrombolysis eligibility.

Randomized trial of radiotherapy plus concurrent-adjuvant chemotherapy vs radiotherapy alone for regionally advanced nasopharyngeal carcinoma

BACKGROUND

Current practice of adding concurrent-adjuvant chemotherapy to radiotherapy (CRT) for treating advanced nasopharyngeal carcinoma is based on the Intergroup-0099 Study published in 1998. However, the outcome for the radiotherapy-alone (RT) group in that trial was substantially poorer than those in other trials, and there were no data on late toxicities. Verification of the long-term therapeutic index of this regimen is needed.

METHODS

Patients with nonkeratinizing nasopharyngeal carcinoma staged T1-4N2-3M0 were randomly assigned to RT (176 patients) or to CRT (172 patients) using cisplatin (100 mg/m(2)) every 3 weeks for three cycles in concurrence with radiotherapy, followed by cisplatin (80 mg/m(2)) plus fluorouracil (1000 mg per m(2) per day for 4 days) every 4 weeks for three cycles. Primary endpoints included overall failure-free rate (FFR) (the time to first failure at any site) and progression-free survival. Secondary endpoints included overall survival, locoregional FFR, distant FFR, and acute and late toxicity rates. All statistical tests were two-sided.

RESULTS

The two treatment groups were well balanced in all patient characteristics, tumor factors, and radiotherapy parameters. Adding chemotherapy statistically significantly improved the 5-year FFR (CRT vs RT: 67% vs 55%; P = .014) and 5-year progression-free survival (CRT vs RT: 62% vs 53%; P = .035). Cumulative incidence of acute toxicity increased with chemotherapy by 30% (CRT vs RT: 83% vs 53%; P < .001), but the 5-year late toxicity rate did not increase statistically significantly (CRT vs RT: 30% vs 24%; P = .30). Deaths because of disease progression were reduced statistically significantly by 14% (CRT vs RT: 38% vs 24%; P = .008), but 5-year overall survival was similar (CRT vs RT: 68% vs 64%; P = .22; hazard ratio of CRT = 0.81, 95% confidence interval = 0.58 to 1.13) because deaths due to toxicity or incidental causes increased by 7% (CRT vs RT: 1.7% vs 0, and 8.1% vs 3.4%, respectively; P = .015).

CONCLUSIONS

Adding concurrent-adjuvant chemotherapy statistically significantly reduced failure and cancer-specific deaths when compared with radiotherapy alone. Although there was no statistically significant increase in major late toxicity, increase in noncancer deaths narrowed the resultant gain in overall survival.

Statins for asymptomatic middle cerebral artery stenosis: The Regression of Cerebral Artery Stenosis study

BACKGROUND

The progression of cerebral atherosclerosis increases the risk of stroke and vascular events. Given the known benefits of statins in retarding coronary and carotid atherosclerosis progression, we studied the effects of statins on asymptomatic middle cerebral artery (MCA) stenosis progression.

METHODS

We conducted a randomized, double-blind, placebo-controlled study to evaluate the effects of simvastatin on the progression of MCA stenosis among stroke-free individuals who had mild to moderately elevated LDL cholesterol (3.0-5.0 mmol/l). Two hundred and twenty-seven subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The severity of MCA stenosis at baseline and at the end of the study was graded by MRA into normal, minimal (<10%), mild (10-49%), moderate (50-90%) and severe (>90%). The primary outcome was the change in grading of MCA stenosis over 2 years.

RESULTS

At the end of the study, the LDL cholesterol level decreased by 1.43 and 0.12 mmol/l for the active and placebo groups, respectively (p < 0.001). There was no significant difference in the proportion of patients having stable, progressive and regressive MCA stenosis between the placebo (72, 22 and 6%) and active groups (78.6, 15.5 and 5.8%). The all-cause mortality was significantly lower in the active group (n = 0) relative to the placebo group (n = 7, p = 0.014). Any clinical events were also lower in the active group (n = 5) than in the placebo group (n = 13, p = 0.052).

CONCLUSIONS

Simvastatin 20 mg daily had no apparent effect upon the evolution of asymptomatic MCA stenosis over 2 years.

Radiation dose measurements for personnel performing 90Y-ibritumomab tiuxetan administration: a comparison between two injection methods for dose reduction

The purpose of this study was to directly measure, using thermoluminescent dosimeters, the radiation doses received by radiation team members performing (90)Y-ibritumomab tiuxetan administration. The occupational doses associated with two injection methods for patient administration - an automatic syringe driver and an injection box - were compared. The associated risks, namely cancer induction and hereditary effect, were also estimated from the results and compared with risk factors recommended by the International Commission on Radiological Protection publication 103. The results showed that the doses received by the index and thumb of the right hand and the index finger of the left hand of the radiation oncologist were significantly reduced by using the injection box method. The difference in the dose received by the medical physicist using the two methods was not statistically significant. It was observed that three pairs of latex gloves could further reduce the dose to the hands. The radiological risks of cancer induction and hereditary effect were negligible: of the order of 10(-6) and 10(-7) per (90)Y-ibritumomab tiuxetan administration, respectively, for both methods. However, the results of our study also showed that it would be possible in a busy centre for pregnant women to receive a dose of (90)Y-ibritumomab tiuxetan that exceeds the recommended annual dose limit for the surface of the abdomen.

Tumor resensitization to erlotinib following brief substitution of cetuximab

Targeted inhibition of epidermal growth factor receptors (EGFR) is becoming a standard anticancer treatment in defined clinical scenarios. EGFR inhibition may be achieved either by small-molecule orally bioavailable tyrosine kinase inhibitors, such as gefitinib or erlotinib, or else by large-molecule receptor antibodies, such as cetuximab or panitumumab. Here, we describe a case of pancreatic cancer in which the small-molecule EGFR antagonist erlotinib was used before and after the EGFR antibody cetuximab, with unexpected potentiation of both toxic and therapeutic sequelae.

Diagnostic value and safety of long-term video-EEG monitoring

This paper aimed to assess the usefulness and safety of video-EEG (video-electroencephalography) monitoring in patients with refractory epilepsy. We analysed the video-EEG recordings of consecutive patients over a 3-year period from 2002 to 2005. The pre-admission diagnosis, demographic information, number of ictal episodes, adverse events, and final diagnosis were recorded in all patients. The diagnostic labels before and after monitoring were compared in order to assess whether it had led to a change in diagnosis and management. Of the 100 patients who underwent video-EEG, 227 clinical events were recorded in 62 cases. The most common events were complex partial seizures followed by non-epileptic attacks. Video-EEG allowed a diagnosis to be made in 81 patients and the diagnosis at discharge was altered in 19 cases. Major injuries and status epilepticus did not occur during monitoring. In our experience video-EEG is safe and provides important clinical information in over 80% of patients.

Spontaneous basilar artery dissection

Dissection of the basilar artery is rare. We report a 51-year-old man who developed acute pontine infarction associated with dissection of the distal basilar artery. There was no trauma or unaccustomed movement of the head and neck prior to the stroke. The dissection was diagnosed non-invasively by magnetic resonance imaging and magnetic resonance angiography. Cervicocerebral artery dissection is a common cause of stroke in young patients particularly when conventional cardiovascular risk factors are absent. Magnetic resonance angiography combined with magnetic resonance imaging is a useful diagnostic tool prior to invasive angiography.

A pre-optimised dosimetry system using a rigid applicator for intracavitary treatment of cervical carcinoma

AIMS

Tumour control and complication risk have been major concerns in the treatment of cervical carcinoma. A review of dose distribution for intracavitary treatment of cervical carcinoma revealed that modification of the Manchester dosimetry system is necessary for cases of narrow-sized vagina. A revised dosimetry system was introduced in the present study, with the objective of optimising the dose coverage for the parametrium while minimising the bladder and rectum dosage by restricting the rectal dose so as not to exceed 75% of the brachytherapy prescription dose.

MATERIALS AND METHODS

A suitable-sized applicator was selected according to the patient's anatomy. The revised system is optimised based on the fixed geometry of the applicator. The system was therefore predefined and the distribution of the treatment dose already determined before application. The revised system was applied to 135 cases, involving 540 applications. The clinical outcome in terms of local tumour control and complication rates is reported. The differences between the revised system and the Manchester system in terms of dose coverage for the parametrium and the rectum dose were compared.

RESULTS

The results showed that higher rectal and parametrial dosages were obtained with the Manchester system as compared with the revised system. Our study showed that over 50% of our patients would have received a rectal dose close to 100% of the point A dose if the Manchester system was applied, whereas it was restricted to below 75% using the revised system. Using the revised system, the significance of the parametrial dosage coverage in relation to local control was assessed: the mean dose to the rectum and the bladder as a percentage of point A was 65.7 +/- 5% (range 50-85%) and 66.4 +/- 14% (range 29-116%), respectively. The 5-year actuarial local failure-free survival rates were 90, 92.9, 86.8, 100, 69.7 and 0% for stages IB, IIA, IIB, IIIA, IIIB and IV (P < 0.0001), respectively. The 3-year actuarial complication rates (grade 3/4) for proctitis and cystitis were 1.4 and 0.5%, respectively. The dosage coverage for the parametrium was found to be significant (P = 0.029) in relation to local control for early-stage disease.

CONCLUSIONS

The favourable local tumour control and low complication rates shown by our results indicate that the revised system presents an optimal dose distribution, particularly for the application of small ovoids, whereas morbidity was reduced to a lower level without compromising local control.

Quality of life of victims of intimate partner violence

OBJECTIVE

To evaluate the impact of intimate partner violence on the quality of life in Obstetric/Gynecological (OBGYN) patients.

METHOD

A total of 1614 OBGYN patients were classified into four groups (Group 1: requesting termination of pregnancy, n=300; Group 2: infertility patients, n=500; Group 3: other general gynecological patients, n=300; Group 4: obstetric patients, n=514) were successfully interviewed in the absence of their male partners, using a structured questionnaire modified from the Abuse Assessment Screen Questionnaire. Those who reported ever having been abused, together with an equal number of non-abused women as controls, were asked to complete the World Health Organization Quality of Life Measure - Abbreviated version (Hong Kong) Questionnaire.

RESULTS

The overall lifetime prevalence of intimate partner violence was 7.2%, with the lifetime prevalence being 12.7%, 1.8%, 4.7%, and 10.9% respectively in Groups 1-4. The mean quality of life domain scores among the abused victims were significantly lower in the physical health domain, social relationship domain, environment domain and psychological health domain.

CONCLUSION

The baseline quality of life of the victims of intimate partner violence is significantly impaired compared with the non-abused controls.

Preliminary Results of a Randomized Study on Therapeutic Gain by Concurrent Chemotherapy for Regionally-Advanced Nasopharyngeal Carcinoma: NPC-9901 Trial by the Hong Kong Nasopharyngeal Cancer Study Group

Purpose

This randomized study compared the results achieved by concurrent chemoradiotherapy (CRT) versus radiotherapy (RT) alone for nasopharyngeal carcinoma (NPC) with advanced nodal disease.

Patients and Methods

Patients with nonkeratinizing/undifferentiated NPC staged T1-4N2-3M0 were randomized to CRT or RT. Both arms were treated with the same RT technique and dose fractionation. The CRT patients were given cisplatin 100 mg/m2 on days 1, 22, and 43, followed by cisplatin 80 mg/m2 and fluorouracil 1,000 mg/m2/d for 96 hours starting on days 71, 99, and 127.

Results

From 1999 to January 2004, 348 eligible patients were randomly assigned; the median follow-up was 2.3 years. The two arms were well-balanced in all prognostic factors and RT parameters. The CRT arm achieved significantly higher failure-free survival (72% v 62% at 3-year, P = .027), mostly as a result of an improvement in locoregional control (92% v 82%, P = .005). However, distant control did not improve significantly (76% v 73%, P = .47), and the overall survival rates were almost identical (78% v 78%, P = .97). In addition, the CRT arm had significantly more acute toxicities (84% v 53%, P < .001) and late toxicities (28% v 13% at 3-year, P = .024).

Conclusion

Preliminary results confirmed that CRT could significantly improve tumor control, particularly at locoregional sites. However, there was significant increase in the risk of toxicities and no early gain in overall survival. Longer follow-up is needed to confirm the ultimate therapeutic ratio.

A randomised controlled trial of empowerment training for Chinese abused pregnant women in Hong Kong

OBJECTIVE

To evaluate the effectiveness of an empowerment intervention in reducing intimate partner violence (IPV) and improving health status.

DESIGN

Randomised controlled trial.

SETTING

Antenatal clinic in a public hospital in Hong Kong.

SAMPLE

One hundred and ten Chinese pregnant women with a history of abuse by their intimate partners.

METHODS

Women were randomised to the experimental or control group. Experimental group women received empowerment training specially designed for Chinese abused pregnant women while the control group women received standard care for abused women. Data were collected at study entry and six weeks postnatal.

MAIN OUTCOMES MEASURES

IPV [on the Conflict Tactics Scale (CTS)], health-related quality of life (SF-36) and postnatal depression [Edinburgh Postnatal Depression Scale (EPDS)].

RESULTS

Following the training, the experimental group had significantly higher physical functioning and had significantly improved role limitation due to physical problems and emotional problems. They also reported less psychological (but not sexual) abuse, minor (but not severe) physical violence and had significantly lower postnatal depression scores. However, they reported more bodily pain.

CONCLUSION

An empowerment intervention specially designed for Chinese abused pregnant women was effective in reducing IPV and improving the health status of the women.

Treatment results for nasopharyngeal carcinoma in the modern era: the Hong Kong experience

PURPOSE

To analyze the treatment results achievable for nasopharyngeal carcinoma in the modern era to identify the key failures for future improvement and to provide an updated baseline for future trials.

METHODS AND MATERIALS

The results of 2687 consecutive patients treated at all public oncology centers in Hong Kong during 1996-2000 were retrospectively analyzed. The stage distribution (by American Joint Committee on Cancer and International Union Against Cancer staging system, 1997) was 7% Stage I, 41% Stage II, 25% Stage III, and 28% Stage IVA-B. All patients were irradiated with 6-MV photons and the median total dose was 66 Gy. Only 23% of patients had additional treatment with chemotherapy.

RESULTS

The 5-year local, nodal, and distant failure-free rates were 85%, 94%, and 81%, respectively; patients with local failure had significantly higher risk of nodal and distant failures. The 5-year progression-free, overall, and cancer-specific survival rates were 63%, 75%, and 80%, respectively. The presenting stage was the most important prognostic factor for all endpoints: with overall survival decreasing from 90% for Stage I to 58% for Stage IVA-B. The results achieved by the 2070 patients treated by radiotherapy alone were almost identical to that of the whole series, the distant failure-free rate among patients with locoregional control was 89% for Stage I-II and 75% for Stage III-IVB. The 860 patients (32%) staged with magnetic resonance imaging achieved significantly better results than those staged by computed tomography, the overall survival being 93% vs. 83% for Stages I-II, and 72% vs. 63% for Stages III-IVB (p = 0.001).

CONCLUSIONS

Treatment results for nasopharyngeal carcinoma have substantially improved in the modern era; future trials should be based on updated baseline results. Further reduction of distant failure is important for future breakthrough, particularly for patients with advanced disease.

Treatment results of endometrial carcinoma with positive peritoneal washing, adnexal involvement and serosal involvement

AIMS

To review the treatment results of patients with endometrial carcinoma having positive peritoneal washing (PPW), adnexal involvement, uterine serosal involvement, or all three.

MATERIALS AND METHODS

The treatment records of patients who had undergone primary surgery for endometrial cancer without distant metastasis during 1990--2001 at the Department of Clinical Oncology, Tuen Mun Hospital, Hong Kong, were reviewed. Thirty-five patients were found to have involvement of positive PPW, adnexal involvement, uterine serosal involvement, or all three. Seven (20%) of them had gross or microscopic lymph-node metastasis. Thirty-three (94.3%) patients received adjuvant radiotherapy (28 whole-pelvic irradiation [WPI]; five abdominal radiotherapy [WART]). Two patients with solitary ovarian metastasis received chemotherapy, and one with isolated PPW also received adjuvant hormonal therapy. The median follow-up was 50.4 months (range 2.4-151.2 months). Multivariate analysis was carried out using the Cox regression proportional hazards model.

RESULTS

Among the 28 patients with clinical or pathological node-negative disease (International Federation of Gynecology and Obstetrics [FIGO] stage IIIA), only two patients with solitary ovarian metastases developed recurrence. The 5-year actuarial disease-free survival (DFS) rates for the whole group and patients without lymph-node involvement were 77.9% and 91.7%, respectively. Five out of the seven patients with lymph-node involvement developed recurrences. Univariate analysis showed that lymph-node involvement (P < 0.0001) and high-grade disease (P = 0.011) were the significant poor prognostic factors. Multivariate analysis showed that lymph-node involvement was the only significant poor prognostic factor to predict poor 5-year DFS (P = 0.0001). Only one patient (3.7%) who had received WART developed grade 4 toxicity.

CONCLUSIONS

This study showed that good treatment results could be obtained from patients with stage IIIA endometrial carcinoma without clinical or pathological lymph-node involvement after adjuvant radiotherapy, with acceptable late side-effects. The relative prognostic importance of individual IIIA involvement and the optimal adjuvant treatment remain to be determined.

Staging of Nasopharyngeal Carcinoma: Suggestions for Improving the Current UICC/AJCC Staging System11Presented in part at the 4th International UICC Symposium on Nasopharyngeal Carcinoma, Hong Kong, February 2003

AIMS

To evaluate the current UICC/AJCC Staging System for nasopharyngeal carcinoma and to search for ways of improving the system.

MATERIALS AND METHODS

This is a retrospective analysis of 2687 consecutive patients treated in five public centres in Hong Kong during the period 1996-2000. All patients were staged by computed tomography, magnetic resonance imaging, or both. The prognostic significance of the current stage assignment on various aspects of tumour control was evaluated.

RESULTS

T-category, N-category and stage-group were all significant prognostic factors for major end points (P < 0.01). However, the distinction of prognosis between Stage I and II was insignificant (5-year cancer-specific survival being 92% vs 95%; P = 0.13). Multivariate analyses (corrected for age and sex) revealed lack of significance between T2a and T1 in hazards of local and distant failures, N3a and N2 in distant failure and subgroups of T1-2N0 in cancer-specific deaths. Corresponding down-staging of T2a to T1, N3a to N2, and subgroup T2N0 to stage I, resulted in more even and orderly increase in the hazard ratio of cancer-specific deaths (from 1 for stage I to 1.98 for II, 3.5 for III, 6.08 for IVA and 8.62 for IVB), better hazard consistency among subgroups of the same stage and more balanced stage distribution.

CONCLUSIONS

The current UICC/AJCC Staging System could be further improved by the modifications suggested; validation of the current proposal by external data is urgently awaited.

Alveolar rhabdomyosarcoma of the cervix

BACKGROUND

Alveolar rhabdomyosarcoma (RMS) has a high risk for local and distal failure. Multimodal management of a patient with alveolar RMS of the cervix uteri is outlined.

CASE

A 39-year-old woman suffered from alveolar RMS of the cervix without involvement of uterus and parametrium. She was treated with total hysterectomy and left salpingo-oophorectomy. Systemic chemotherapy and pelvic irradiation were also offered. She remains in clinical remission 3 years after presentation.

CONCLUSION

Postoperative chemotherapy and irradiation could be effective treatments for alveolar rhabdomyosarcoma of the cervix in adult patients.

CT verification of isocentre relocatability using stereotactic mask fixation system

AIMS

This study introduces a non-invasive method based on computed tomography (CT) verification to ensure patients are accurately positioned before fractionated stereotactic radiotherapy. It enables quality control of mask positioning with reference to the CT images of the treatment plan.

MATERIALS AND METHODS

A mask system, together with a dental impression moulded mouth bite, was used for patient immobilisation. In order to facilitate relevant image comparison, special alignment during CT localisation was discussed in the study. The accuracy of patient set-up was studied by assessing the isocentre position in relation to the patient's anatomical structure. The planning CT images were applied as a reference and the study was applied to 261 cranial applications.

RESULTS

The results show that the mean and the maximum overall displacements at the isocentre were 0.7 and 2.5 mm, respectively. The mean and the maximum rotational displacement in the axial plane were 0.56 degrees and 2 degrees, respectively. The mean translational displacement and rotational displacement were close to zero when considering the direction of movement.

CONCLUSIONS

The results indicate that the systematic error of the mask system and the verification method are minimal. Advantages of this technique include the simple set-up, three-dimensional quantification and short study time (10-15 min). It is therefore practical to implement on a routine basis. Investigation of the ability to relocate the mask is also recommended to justify the required safety margin between the clinical and planning target volumes.

Domestic violence and postnatal depression in a Chinese community

OBJECTIVES

To study the relationship between domestic violence and postnatal blues/depression in a Chinese community.

METHODS

This was a prospective cohort study on 838 women after delivery in a local university teaching hospital. Between October, 2000 and February, 2001, all Chinese speaking women after delivery were invited to be interviewed by a designated research nurse using the Abuse Assessment Screen (AAS) to detect the incidence of domestic violence, the nature of violence and the perpetrator of abuse. Demographic data, pregnancy outcome, Stein's Daily Scoring System (SDSS) scores on day 2 or 3 postdelivery, Edinburgh Postnatal Depression Scale (EPDS) scores on day 2 or 3 postdelivery, 1-2 days after discharge from hospital and at 6 weeks postdelivery were compared between the abused and non-abused groups using Student's t-test, chi(2)-test and Fisher's exact test as appropriate.

RESULTS

A total of 139 women (16.6%) had been abused in the last year (the abused group). Of these, 87 (10.4%) had been abused during the current pregnancy. The nature of abuse was mainly verbal. Fourteen women (1.7%) had been sexually abused in the last year. The husband/boyfriend, mother-in-law and employer/colleague were the most common perpetrators of abuse. Socio-demographic factors did not differ between the two groups except that pregnancy was more likely to be unplanned in the abused group (P=0.002). The pregnancy outcome did not differ. However, the abused group had significantly higher SDSS and EPDS scores at all stages of screening (P=0.003, P=0.000, P=0.010 and P=0.001, respectively).

CONCLUSION

The findings supported our hypothesis that the effect of domestic violence on Chinese pregnant women is mainly on their psychological well-being.

Concurrent chemotherapy-radiotherapy compared with radiotherapy alone in locoregionally advanced nasopharyngeal carcinoma: progression-free survival analysis of a phase III randomized trial

PURPOSE

Nasopharyngeal carcinoma (NPC) is highly sensitive to both radiotherapy (RT) and chemotherapy. This randomized phase III trial compared concurrent cisplatin-RT (CRT) with RT alone in patients with locoregionally advanced NPC.

PATIENTS AND METHODS

Patients with Ho's N2 or N3 stage or N1 stage with nodal size > or = 4 cm were randomized to receive cisplatin 40 mg/m(2) weekly up to 8 weeks concurrently with radical RT (CRT) or RT alone. The primary end point was progression-free survival (PFS).

RESULTS

Three hundred fifty eligible patients were randomized. Baseline patient characteristics were comparable in both arms. There were significantly more toxicities, including mucositis, myelosuppression, and weight loss in the CRT arm. There were no treatment-related deaths in the CRT arm, and one patient died during treatment in the RT-alone arm. At a median follow-up of 2.71 years, the 2-year PFS was 76% in the CRT arm and 69% in the RT-alone arm (P =.10) with a hazards ratio of 1.367 (95% confidence interval [CI], 0.93 to 2.00). The treatment effect had a significant covariate interaction with tumor stage, and a subgroup analysis demonstrated a highly significant difference in favor of the CRT arm in Ho's stage T3 (P =.0075) with a hazards ratio of 2.328 (95% CI, 1.26 to 4.28). For T3 stage, the time to first distant failure was statistically significantly different in favor of the CRT arm (P =.016).

CONCLUSION

Concurrent CRT is well tolerated in patients with advanced NPC in endemic areas. Although PFS was not significantly different between the concurrent CRT arm and the RT-alone arm in the overall comparison, PFS was significantly prolonged in patients with advanced tumor and node stages.

A comparison of the prevalence of domestic violence between patients seeking termination of pregnancy and other general gynecology patients

OBJECTIVES

(1) To determine and compare the prevalence of domestic violence among abortion-seeking patients with other general gynecology patients; (2) to see if a follow-up interview 6 weeks after abortion can improve the abuse disclosure rate; (3) to see if the abused victims accept direct referral to their gynecologists/social workers for help.

METHODS

This is a prospective questionnaire survey in a university teaching hospital on patients seeking abortion and an approximately equal number of other general gynecology patients. Participants were interviewed by a designated project nurse in a private setting, using a structured questionnaire (Modified Abuse Assessment Screen Questionnaire) to assess the past and recent history of abuse. The interview was repeated 6 weeks after the abortion for the abortion-seeking group.

RESULTS

Five hundred and one participants were interviewed, including 245 seeking abortion (TOP group) and 256 other general gynecology patients (non-TOP group). The lifetime prevalence of abuse in the TOP group (27.3%) was significantly higher than the non-TOP group (8.2%) (P<0.001). Repeating the interview 6 weeks after the abortion did not increase the disclosure rate. Most abused victims were unwilling to disclose their information of abuse to their gynecologists or social workers at the time of interview.

CONCLUSIONS

Domestic violence is a significant problem among the gynecology patients, particularly those seeking abortion. A single interview prior to abortion is adequately effective for screening. However, the most effective and acceptable way of helping these victims needs to be explored further.

Sphenoid sinus mucocoele and cranial nerve palsies in a patient with a history of nasopharyngeal carcinoma: may mimic local recurrence

We report the case history of a patient with a sphenoid sinus mucocoele detected by computed tomography and medical resonance imaging. The patient had a history of nasopharyngeal carcinoma, which was treated by radiotherapy more than 10 years previously. He presented with bilateral twelfth and sixth cranial nerve palsies. Local tumour recurrence was suspected. Further investigations showed that the cranial nerve palsies were caused by radiation damage and the sphenoid sinus mucocoele was an incidental finding. Sphenoid sinus mucocoele is a possible rare late complication of radiotherapy in patients with nasopharyngeal carcinoma.

Application of classification tree and neural network algorithms to the identification of serological liver marker profiles for the diagnosis of hepatocellular carcinoma

OBJECTIVE

Although many attempts have been made to identify tumour-specific alpha-fetoprotein (AFP) glycoforms or other serological markers for the diagnosis of hepatocellular carcinoma (HCC), none of the available markers has, so far, shown satisfactory sensitivity and specificity. Here we aimed to apply classification tree and neural network algorithms to interpret the levels of multiple serological liver markers to improve overall specificity and sensitivity, particularly with a view to discriminating between liver cirrhosis with and without HCC.

METHODS

We developed classification trees and neural networks that identified serological liver marker profiles comprising AFP, alpha1-antitrypsin (A1AT), alpha2-macroglobulin (A2MG), thyroxine-binding globulin (TBG), transferrin and albumin as well as sex and age, which might permit the diagnosis of HCC. Data were collected from 65 HCC patients, 51 patients with liver cirrhosis alone (LC) and 51 normal healthy subjects.

RESULTS

The generated classification trees and neural networks showed similar diagnostic values in differentiating HCC from LC. The classification trees identified AFP, A1AT and albumin as the most important classification parameters, whereas the neural networks identified A2MG, AFP, A1AT and albumin as the predominant factors. The classification logic of the classification trees indicated that more HCC cases could be identified among cases with slightly elevated AFP levels by using the serum levels of A1AT and albumin. The neural networks were also useful for the identification of the HCC cases when the AFP levels were below 500 ng/ml (p < 0.005). The neural networks could identify HCC cases with AFP levels within the normal range, but the classification trees could not. By combining the conventional AFP test and the neural networks, the overall diagnostic sensitivity for HCC was significantly increased from 60.0 to 73.8% (p < 0.05) while maintaining a high specificity (88.2%). The sensitivities for tumors of different sizes were similar.

CONCLUSION

The neural network algorithm appeared to be more powerful than the classification tree algorithm in the identification of the distinctive serological liver marker profiles for the diagnosis of the HCC subgroup without significant elevation in serum AFP levels. By incorporating serological levels of other liver markers and including data from a large number of patients and control subjects, it should prove possible to develop a versatile neural network for early diagnosis of HCC.

Over-expression of FoxM1 stimulates cyclin B1 expression

FoxM1 (previously named WIN, HFH-11 or Trident) is a Forkhead box (Fox) transcription factor widely expressed in proliferating cells. Various findings, including a recent analysis of FoxM1 knockout mice, suggest that FoxM1 is required for normal S-M coupling during cell cycle progression. To study the regulatory role of FoxM1 and its downstream regulatory targets, three stably transfected HeLa lines that display doxycycline (dox)-inducible FoxM1 expression were established. Over-expression of FoxM1 by dox induction facilitates growth recovery from serum starvation. Quantitation of cyclin B1 and D1 levels using flow cytometric, Western and Northern analyses reveals that elevated FoxM1 levels lead to stimulation of cyclin B1 but not cyclin D1 expression. Transient reporter assays in the dox-inducible lines and upon co-transfection with a constitutive FoxM1 expression plasmid suggest that FoxM1 can activate the cyclin B1 promoter.

Systemic therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common cancer worldwide. Most patients present at a stage when surgical resection is no longer possible, and face a dismal prognosis. Locoregional and intra-arterial treatments are feasible and effective only in selected patients with disease confined to the liver. For patients with extrahepatic disease or a blocked portal venous system, systemic chemotherapy is the only treatment option available. Systemic therapy has not been successful in the past, with very low response rates to single-agent chemotherapy. Recently, however, there have been reports that combination chemotherapy with currently available agents may make some initially unresectable tumors resectable and, in some cases, induce complete pathologic responses. This has led to a reconsideration of systemic therapy for HCC, the current status of which is described in this review.

Late temporal lobe necrosis in patients with nasopharyngeal carcinoma: evaluation with combined multi-section diffusion weighted and perfusion weighted MR imaging

Late temporal lobe necrosis is a well-known and serious complication in patients with nasopharyngeal carcinoma (NPC) following radiotherapy. Owing to the close proximity to the skull base, the medial temporal lobes are inevitably included in the target volume of irradiation. Patients with NPC provide a unique opportunity in study of delay radiation effect in normal human brain. The objective of this study was to evaluate late temporal lobe radiation injury by combined multi-section diffusion weighted and perfusion weighted MR imaging. We prospectively studied 16 patients with typical clinical symptoms of late temporal lobe necrosis or other abnormalities in the temporal lobes incidentally detected by conventional MR imaging. All patients had a previous history of radiotherapy for histologically proven NPC. Conventional T1- and T2-weighted images, fast gradient echo with echo-planar diffusion-weighted and perfusion-weighted MR imaging were performed. Apparent diffusion coefficient (ADC) map and relative cerebral blood volume (rCBV) map were computed via commercially available software. MR diffusion and perfusion images were then analyzed and graded by two independent observers with focusing on the diffusion and perfusion mismatch. The temporal lobe lesions displayed marked high diffusion on the ADC map. The rCBV map also revealed marked hypoperfusion in these temporal lobe lesions in all patients. The areas of abnormality on the rCBV map were significantly larger than the lesions on the ADC map in 14 patients (observer 1) and 13 patients (observer 2). Since late temporal lobe necrosis is probably caused by damage of the endothelium of vessels and ischemia, perfusion and diffusion mismatch might imply injured tissue but potentially salvageable brain tissue. A mismatch may be potentially used to predict the response to treatment in-patients with late temporal lobe necrosis.

Expressions of c-erbB-2, epidermal growth factor receptor and pan-ras proto-oncogenes in adenocarcinoma of the cervix: correlation with clinical prognosis

The expressions of c-erbB-2, epidermal growth factor receptor (EGFR) and pan-ras in normal cervical glands (n=45), glandular dysplasia/adenocarcinoma in situ (GIN/ACIS) (n=32) and invasive cervical adenocarcinoma (n=78) were determined and correlated with clinical prognosis. The expressions of c-erbB-2, EGFR and pan-ras in GIN/ACIS lesions and invasive tumours were significantly higher than in normal glands (p<0.001), whereas there was no significant difference between expressions in GIN/ACIS lesions and invasive tumours, except for EGFR (p=0.016). Significantly more normal glands adjacent to adenocarcinoma showed moderate/strong expressions for EGFR than c-erbB-2 (p=0.007) whereas significantly more GIN/ACIS lesions showed moderate/strong expressions for c-erbB-2 than EGFR (p=0.008). No correlation was found between moderate/strong expressions for c-erbB-2, EGFR or pan-ras and stage at presentation (p=0.384, 0.056, 0.842 respectively) or with survival (p=0.58, 0.19, 0.26 respectively). In conclusion, EGFR is more important in inducing dysplastic change/malignant transformation whereas c-erbB-2 plays a more significant role in tumour progression and invasion. However, neither c-erbB-2, EGFR nor pan-ras carried any prognostic significance on patient survival.

High incidence of somatic mitochondrial DNA mutations in human ovarian carcinomas

To investigate the potential role of somatic mitochondrial DNA (mtDNA) mutations in tumorigenesis, the occurrence of mutations in mtDNA of ovarian carcinomas was studied. We sequenced the D-loop region of mtDNA of 15 primary ovarian carcinomas and their matched normal controls. Somatic mtDNA mutations were detected in 20% (3 of 15) tumor samples carrying single or multiple changes. Complete sequence analysis of the mtDNA genomes of another 10 pairs of primary ovarian carcinomas and control tissues revealed somatic mtDNA mutations in 60% (6 of 10) of tumor samples. Most of these mutations were homoplasmic, and most were T-->C or G-->A transitions, but one represented a differential length within a run of identical C residues. A region of mtDNA sequence including the 16S and 12S rRNA genes, the D-loop and the cytochrome b gene, may represent the zone of preferred mtDNA mutation in ovarian cancer. The high incidence of mtDNA mutations found in ovarian carcinomas and other human cancers suggests that genetic instability of mtDNA might play a significant role in tumorigenesis.

Selective internal radiation therapy by yttrium-90 microspheres for hepatocellular carcinoma after renal transplantation

We report a HBsAg-positive patient who developed hepatocellular carcinoma (HCC) 7 years after cadaveric kidney transplantation. The tumor was unresectable because of coexisting cirrhosis. Selective internal radiation (SIR) therapy, a novel therapy with the technique recently perfected, was used. Yttrium-90 microspheres were given via an angiographic catheter under fluoroscopy guidance. Serum alpha-fetal protein (AFP) was normalized within 2 wk. A follow-up abdominal CT scan revealed significant necrosis of the tumor and compensatory hypertrophy of non-diseased liver. The treatment was well tolerated except for transient liver function deterioration. The patient enjoyed 15 months of symptom-free survival before she died of liver failure. Practical aspects and potential applications of SIR therapy in this group of patients are discussed.