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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. [Copyright &y& Elsevier]

The protracted COVID-19 pandemic has overwhelmed health systems globally, including many aspects of cancer control. This has underscored the multidimensional nature of cancer control, which requires a more comprehensive approach involving taking a wider perspective of health systems. Here, we investigated aspects of health system resilience in maintaining cancer services globally during the COVID-19 pandemic. This will allow for health systems to be resilient to different types of system stressors/shocks in the future, to allow cancer care to be maintained optimally. Using the World Health Organization health system framework (capturing aspects of service delivery, health workforce, information, medical products, vaccines and technologies, financing and governance and leadership), we carried out a comparative analysis of the impact of COVID-19 and the synthesis of the findings in responses in cancer care in 10 countries/jurisdictions across four continents comprising a wide diversity of health systems, geographical regions and socioeconomic status (China, Colombia, Egypt, Hong Kong SAR, Indonesia, India, Singapore, Sri Lanka, UK and Zambia). A combination of literature and document reviews and interviews with experts was used. Our study revealed that: (i) underlying weaknesses of health systems before the pandemic were exacerbated by the pandemic (e.g. economic issues in low- and middle-income countries led to greater shortage of medication and resource constraints compounded by inadequacies of public financing and issues of engagement with stakeholders and leadership/governance); (ii) no universal adaptive strategies were applicable to all the systems, highlighting the need for health systems to design emergency plans based on local context; (iii) despite the many differences between health systems, common issues were identified, such as the lack of contingency plan for pandemics, inadequate financial policies for cancer patients and lack of evidence-based approaches for competing priorities of cancer care/pandemic control. We identified four key points/recommendations to enhance the resilient capacity of cancer care during the COVID-19 pandemic and other system stressors: (i) effective pandemic control approaches in general are essential to maintain the continuity of cancer care during the emergency health crises; (ii) strong health systems (with sufficient cancer care resources, e.g. health workforce, and universal health coverage) are fundamental to maintain quality care; (iii) the ability to develop response strategies and adapt to evolving evidence/circumstances is critical for health system resilience (including introducing systematic, consistent and evidence-based changes, national support and guidance in policy development and implementation); (iv) preparedness and contingency plans for future public health emergencies, engaging the whole of society, to achieve health system resilience for future crises and to transform healthcare delivery beyond the pandemic. • Effective containment of COVID-19 in general led to least disruption of cancer care. • Pre-existing weakness of health systems was exacerbated during the pandemic. • Adaptive strategies need to evolve with evidence and changing circumstances. • Preparedness plans are needed for future shocks to enable systematic response. • Building resilience requires both health system improvements and emergency preparedness. [ABSTRACT FROM AUTHOR]

The majority of new nasopharyngeal cancer (NPC) cases occur in LMICs, but these patients experience poorer overall survival than patients in high income countries. The goal of this study was to determine whether the introduction of a radiotherapy quality assurance (RT QA) program can improve NPC patient outcomes in LMICs. Phase 1 was composed of a survey of RT resources, patient characteristics and treatment, and results of RT QA performed post treatment by the expert panel for 134 patients treated at 10 participating centers. Each center received a detailed RT QA report for every patient they treated. An educational workshop, which included review of all RT QA details for every patient treated during Phase 1, was conducted prior to centers accruing patients for Phase 2. In Phase 2, the feedback from the RT QA performed by the expert panel was given prior to patients commencing treatment to allow for pre-treatment implementation of RT QA feedback. The primary endpoints of the study are: 1) Difference in major protocol deviations (defined as major deviations in contour and/or dosimetry of GTVs, high dose PTV and critical organs at risk (OARs), and 2) comparison of 3-year progression free survival (PFS), between Phase 1 and 2 patient cohorts. The results of the first phase of this study showing 60.4% cases with major protocol deviations have been reported previously. We now report the RT QA findings in the second phase of this study. 154 patients were accrued from 9 centers. 106 (69%) cases were reviewed pre-treatment and 48 (31%) post-treatment. In the pre-treatment group there were 32/106 (30.2%) with major protocol deviations. Among them, one case was not resubmitted, while 31 cases were corrected and resubmitted with 20 assessed as acceptable and 11 remaining unacceptable. In the post-treatment reviews, 6/48 (12.5%) had major protocol deviations. Overall, there were 18/154 (11.7%) cases with major protocol deviations. Introduction of a RTQA program for NPC resulted in a significant reduction in major protocol deviations in Phase 2 compared to the baseline previously documented in Phase 1 (60.4% to 11.7%, p<0.001). At this time there is insufficient follow-up time for comparison of the 3-year PFS in each group, but we are hopeful the major improvement in RT planning quality will translate to future improvement in PFS. [ABSTRACT FROM AUTHOR]

Summary: Pemetrexed is a novel chemotherapy agent with good efficacy and toxicity profiles. This phase II study aimed at evaluating its use in combination with cisplatin for recurrent or metastatic nasopharyngeal carcinoma (NPC). All participating patients had metastatic or recurrent NPC with prior treatment by platinum-based chemotherapy. The study regimen comprised of pemetrexed 500mg/m2 and cisplatin 75mg/m2, repeated 3-weekly for 4 cycles. Efficacy evaluation was based on both radiological and biochemical responses. Patients with no progressive disease and good tolerance were given another 2–4 cycles. Fifteen patients were treated for a total of 4–8 cycles (median, 6 cycles); 9 had distant metastases and 6 had loco-regional recurrences only. Reduction of DNA copies of EB virus by ⩾50% was observed in 93% accessible patients, with 21% of them being biochemical complete response (CR). Radiologically, 1 (7%) patient achieved CR, 2 (13%) achieved partial response and 8 (53%) had stable diseases. The median time to progression was 30weeks. Treatment was well tolerated with only 1 (7%) patient developing grade 4 toxicity (of anemia). The most common grade 3 toxicities were neutropenia (27%) and anemia (20%). The baseline mean total QOL scores (as measured with FACT-H&N version 4) was 100.4 and showed no significant change after the fourth cycle (95.6, p =0.20) and sixth cycle (91.9, p =0.15). Pemetrexed in combination with cisplatin is a well tolerated regimen with encouraging efficacy for metastatic and recurrent NPC. Further evaluation of its role in the management of NPC is warranted. [Copyright &y& Elsevier]

This letter reports the fabrication and demonstration of an ErAs:GaAs interdigitated photomixer as a tunable THz source ranging from ∼20 GHz to ∼2 THz, with 12 μW maximum power typically around ∼90 GHz. Each photomixer is coupled to a composite dipole-spiral planar antenna that emits a Gaussian-type beam into free space. The beam switches from dipole to spiral antenna behavior as the frequency increases. A distributed Bragg reflector is embedded in the device beneath the photomixer to increase its external quantum efficiency. The photomixer has a 900 Å thick silicon nitride coating which serves as an antireflection and passivation layer, and also improves the reliability and heat tolerance of the device. [ABSTRACT FROM AUTHOR]

Cancer is the most common cause of mortality worldwide. Although recent advances of multiple modality cancer management have significantly improved the cure and control rates, a significant proportion of patients are still refractory to the standard and available treatments. Early initiation of palliative care can reduce cancer suffering, improve health-related quality of life and possibly prolong survival. It also allows patients and their caretakers to perceive the trajectory of their cancer, so that better and advanced care planning can be contemplated and implemented. The traditional beliefs and perceptions of cancer also differ significantly between the East and the West, which may also affect the preferential approach to palliative care. This review provides an overview of palliative care services in Hong Kong, as compared with other parts of the world. In addition, we shall also explore how cancer perceptions affect the decision-making on palliative care. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Breast conservation treatment for ductal carcinoma in situ (DCIS) was unpopular in the Chinese population and the outcome was seldom reported. We conducted a single-centre retrospective study to examine the clinical outcome of women in Hong Kong. Materials and methods: Seventy-five Chinese women were treated with wide local excision and radiotherapy for DCIS of the breast between 1994 and 2003. Only 26 (34.7%) women had non-palpable DCIS detected by screening mammograms. All women were treated with whole breast irradiation of 50Gy in 2Gy daily fractions, with 50 (66.7%) women receiving an additional electron boost of 10–16Gy. Results: The median follow-up was 5.1 years (range 2.0–10.7). At the last assessment, four women developed local recurrences, but all remained disease-free after salvage mastectomy. The 5-year actuarial local failure-free rate and cause-specific survival rate were 92.9% (95% confidence interval 89.4–96.4) and 100.0%, respectively. Cosmetic results were rated as good to excellent in all women. On univariate analysis of prognostic factors for local failure, only a close (≤2mm) final resection margin approached statistical significance (hazard ratio 9.108; 95% confidence interval 0.946–87.655; P =0.056). The 5-year actuarial local failure-free rates for women with a close (≤2mm) final resection margin and women with wider margins were 77.0 and 98.2%, respectively. Conclusions: Despite geographical and demographic differences, the clinical outcome after wide local excision and radiotherapy for DCIS of the breast in Chinese women is comparable with that in Western series. Efforts are needed to achieve cosmetically acceptable tumour-free margins greater than 2mm. [Copyright &y& Elsevier]

Aim: To assess the clinical outcome of breast cancer patients with immediate autologous breast reconstruction and post-mastectomy radiotherapy (PMRT) as primary treatment.Materials and methods: Twenty-five women with breast cancer treated with immediate autologous breast reconstruction and post-mastectomy radiotherapy as primary treatment between 1995 and 2001 in Pamela Youde Nethersole Eastern Hospital of Hong Kong were retrospectively studied. Radiation doses of 50 Gy (in 2 Gy daily fraction) were given to the reconstructed breasts, except one who was given 45 Gy (in 1.8 Gy daily fraction). Nine women (36%) were treated without bolus, whereas the other 16 women (64%) were treated with 0.5 cm thick bolus on alternate days. The main outcome measures include local control, treatment complications and cosmetic outcome.Results: Median follow-up was 3.7 years (range: 1.0–6.6 years). Two women (8%), who were treated without bolus, developed chest wall recurrences. The overall 5-year, actuarial, local failure-free rate and disease-specific survival rate were 89.8% and 77.9%, respectively. Apart from mild acute skin reactions, no significant acute radiotherapy side-effects were observed. No flap necrosis or flap loss was seen. The cosmesis of the reconstructed breasts were rated as good to excellent in 85% of the surviving patients. There was no observed adverse effect on cosmesis by adding bolus on alternate days.Conclusion: PMRT after immediate autologous tissue-flap breast reconstruction is well tolerated and is not associated with increased incidence of complications. Adding 0.5 cm bolus on alternate days might improve local control without causing adverse cosmetic effect. The concern of adverse effects of radiotherapy should not exclude the choice of immediate breast reconstruction in suitable patients. [Copyright &y& Elsevier]

This letter reports the use of a photomixing sweep oscillator to characterize samples of B. subtillis spores at room temperature between 200 and 1200 GHz. Dilute (10% by mass) and concentrated samples were tested, the former using fine-grained polyethylene powder as a low-loss dielectric matrix. The dilute sample displays many weak transmission undulations, but the three centered at 418, 1037 and 253 GHz were strong enough to remain after normalization. The concentrated sample displays a much stronger broadband attenuation, precluding accurate measurements above ∼500 GHz. Two broad signatures remain between 250 and 290 GHz, and between 410 and 440 GHz, respectively. The results suggest that single-bioparticle electromagnetic resonance, perhaps from surface phonons, occurs in the dilute sample but is smeared in the concentrated sample. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

To audit the accuracy of magnetic resonance (MR) staging of nasopharyngeal carcinoma (NPC) in daily reporting, the MR images of 101 adult patients with newly diagnosed NPC reported between December 1996 and February 2002 were reviewed retrospectively. Based on the American Joint Committee on Cancer/International Union Against Cancer (AJCC/UICC) TNM staging criteria (1997), the tumour staging obtained from the MR reports and the MR films was compared by two experienced head and neck radiologists. The number of patients being upstaged, downstaged or unchanged was noted. In all stages, the NPC staging obtained from the MR reports revealed 18 (17.8%) understaged, eight (7.9%) overstaged and 75 (74.2%) the same stage when compared to the staging obtained from the MR films based on the AJCC/UICC criteria. The percentage of patients being understaged or overstaged, in decreasing order of frequency, were stages II, III, IV and I. Magnetic resonance of NPC should be reported by radiologists who are not only familiar with the pathology of this condition and its pattern of spread but who should also base their reports on the AICC/UICC staging criteria. The necessity to improve our MR staging accuracy is largely because it determines the type of therapy to be given and this has to be appropriate and adequate for a successful treatment. [ABSTRACT FROM AUTHOR]

Background: Cancer is a global health burden; the outcome varies widely across all countries. Sharing of experience in setting health policy (including health expenditure) is important. However, there is yet no comprehensive comparison of cancer outcome across all countries. Furthermore, comparison of cost-effectiveness of different systems is especially complex because the incidence of different cancers varies across countries, and their chances of curability differ substantially. Aim: We aims to provide the comparisons using available data and to stimulate global attention to the association of economic parameters with different outcomes. Methods: Cancer statistics from all 184 countries and 27 major cancers listed in GLOBOCAN 2012 were analyzed. The overall outcome of cancer patients was estimated by taking the complement of age-standardized mortality/incidence ratio [1 − (ASM/ASI)] as the proxy relative survival (RS). Taking into account the variation of country-specific cancer pattern, the proxy cancer site-standardized RS (SS-RS) of individual countries were calculated by weighting the proportion of specific cancer sites as compared with the global pattern of incidence. The overall economic parameters of different countries listed by the World Bank were correlated with the corresponding proxy SS-RS. Results: The unadjusted proxy RS among the 184 countries ranged from 0.111 to 0.702 (median = 0.386), the corresponding proxy SS-RS ranged from 0.124 to 0.622 (median = 0.359). The median total health expenditure per capita (HE) increased from US$37 for countries with proxy SS-RS < 0.2, to $4255 for countries with proxy SS-RS ≥ 0.5. Results from logarithmic regression model showed exponential increase in total HE for better outcome. The expenditure varied widely among different strata, but the widest difference was observed among countries with SS-RS ≥ 0.5 (with total HE ranging from US$962 to $9361). Conclusion: Similar to age-standardization, estimation of outcome with adjustment for variation in pattern of cancer incidence is suggested for comparison among different countries, especially for studies related to assessment of health systems. Cancer outcome correlated significantly with economic parameters; the amount of HE escalated exponentially and varied widely among countries with high SS-RS ≥ 0.5. Sharing of experience among different countries will be valuable for developing the most cost-effective health system. [ABSTRACT FROM AUTHOR]