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Dive into the research topics where K. H. Yu is active.

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Featured researches published by K. H. Yu.


Journal of Clinical Oncology | 2002

Concurrent Chemotherapy-Radiotherapy Compared With Radiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma: Progression-Free Survival Analysis of a Phase III Randomized Trial

Anthony T.C. Chan; Peter M.L. Teo; R.K. Ngan; Thomas W.T. Leung; Wan-Yee Lau; Benny Zee; Sing Fai Leung; F.Y. Cheung; Winnie Yeo; H.H. Yiu; K. H. Yu; K. W. Chiu; D.T. Chan; Tony Mok; K.T. Yuen; F. Mo; Maria Lai; W. H. Kwan; Paul Cheung-Lung Choi; Philip J. Johnson

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 Hos 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 Hos 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.


International Journal of Radiation Oncology Biology Physics | 1996

Significant prognosticators after primary radiotherapy in 903 nondisseminated nasopharyngeal carcinoma evaluated by computer tomography

Peter M.L. Teo; Peter S. Y. Yu; W.Y. Lee; Sing Fai Leung; W. H. Kwan; K. H. Yu; Peter H.K. Choi; Philip J. Johnson

PURPOSE To evaluate the significant prognosticators in nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS From 1984 to 1989, 903 treatment-naive nondisseminated (MO) NPC were given primary radical radiotherapy to 60-62.5 Gy in 6 weeks. All patients had computed tomographic (CT) and endoscopic evaluation of the primary tumor. Potentially significant parameters (the patients age and sex, the anatomical structures infiltrated by the primary lesion, the cervical nodal characteristics, the tumor histological subtypes, and various treatment variables were analyzed by both monovariate and multivariate methods for each of the five clinical endpoints: actuarial survival, disease-free survival, free from distant metastasis, free from local failure, and free from regional failure. RESULTS The significant prognosticators predicting for an increased risk of distant metastases and poorer survival included male sex, skull base and cranial nerve(s) involvement, advanced Hos N level, and presence of fixed or partially fixed nodes or nodes contralateral to the side of the bulk of the nasopharyngeal primary. Advanced patient age led to significantly worse survival and poorer local tumor control. Local and regional failures were both increased by tumor infiltrating the skull base and/or the cranial nerves. In addition, regional failure was increased significantly by advancing Hos N level. Parapharyngeal tumor involvement was the strongest independent prognosticator that determined distant metastasis and survival rates in the absence of the overriding prognosticators of skull base infiltration, cranial nerve(s) palsy, and cervical nodal metastasis. CONCLUSIONS The significant prognosticators are delineated after the advent of CT and these should form the foundation of the modern stage classification for NPC.


Journal of Clinical Oncology | 2004

Phase II study of neoadjuvant carboplatin and paclitaxel followed by radiotherapy and concurrent cisplatin in patients with locoregionally advanced nasopharyngeal carcinoma: Therapeutic monitoring with plasma Epstein-Barr virus DNA

Anthony T.C. Chan; Brigette Ma; Y.M. Dennis Lo; S. F. Leung; W. H. Kwan; Edwin P. Hui; Tony Mok; Michael Kam; Lisa S. Chan; Samuel K.W. Chiu; K. H. Yu; K.Y. Cheung; Karen Lai; Maria Lai; Frankie Mo; Winnie Yeo; A.D. King; Philip J. Johnson; Peter M.L. Teo; Benny Zee

PURPOSE To assess the efficacy of neoadjuvant paclitaxel and carboplatin (TC) followed by concurrent cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and to monitor treatment response with plasma Epstein-Barr virus (EBV) DNA. PATIENTS AND METHODS Thirty-one patients with International Union Against Cancer stages III and IV undifferentiated NPC had two cycles of paclitaxel (70 mg/m2 on days 1, 8, and 15) and carboplatin (area under the curve 6 mg/mL/min on day 1) on a 3-weekly cycle, followed by 6 to 8 weeks of cisplatin (40 mg/m2 weekly) and RT at 66 Gy in 2-Gy fractions. Plasma EBV DNA was measured serially using the real-time quantitative polymerase chain reaction method. Results All patients completed planned treatment. Response to neoadjuvant TC was as follows: 12 patients (39%) achieved partial response (PR) and 18 achieved (58%) complete response (CR) in regional nodes; five patients (16%) achieved PR and no patients achieved CR in nasopharynx. At 6 weeks after RT, one patient (3%) achieved PR and 30 patients (97%) achieved CR in regional nodes, and 31 patients (100%) achieved CR in nasopharynx; 29 patients (93%) had EBV DNA level of less than 500 copies/mL. Neoadjuvant TC was well tolerated, and the most common acute toxicity of cisplatin plus RT was grade 3 mucositis (55%). At median follow-up of 33.7 months (range, 7 to 39.3 months), six distant and three locoregional failures occurred. Plasma EBV DNA level increased significantly in eight of nine patients who experienced treatment failure but did not increase in those who did not. The 2-year overall and progression-free survival rates were 91.8% and 78.5%, respectively. CONCLUSION This strategy was feasible and resulted in excellent local tumor control. Serial plasma EBV DNA provides a noninvasive method of monitoring response in NPC.


Annals of Surgical Oncology | 2007

Strong Immunohistochemical Expression of Vascular Endothelial Growth Factor Predicts Overall Survival in Head and Neck Squamous Cell Carcinoma

Gary M. Tse; Anthony W.H. Chan; K. H. Yu; Ann D. King; Ka-Tak Wong; George G. Chen; Raymond K. Tsang; Amy B.W. Chan

BackgroundHead and neck squamous cell carcinoma (HNSCC) has high morbidity and mortality, and its relationship with tumor angiogenesis as measured by mircovessel density (MVD) or vascular endothelial growth factor (VEGF) expression has shown mixed results, with some, but not others, reporting correlation with outcome.MethodsA retrospective study of 186 patients with HNSCC was performed. Patients were evaluated for MVD and VEGF and to correlate the levels with clinical parameters, including age at diagnosis, sex, site of tumor, stage, survival (disease free and overall), pathological tumor grade, and the presence of lymph node metastases.ResultsThe 186 cancers included the following sites: oral tongue (n = 69), palate (n = 9), maxillary sinus (n = 8), floor of mouth (n = 13), oropharynx (n = 27), hypopharynx (n = 26) and larynx (n = 34). Over three-quarters of patients had advanced tumor (stage III/IV) and 58.6% had lymph node metastases. MVD and VEGF were assessed in 166 and 164 cases, respectively, but these were not correlated with site and grade. The 3-year overall and disease-free survival rates were 55.4% and 53.2%, respectively. Both univariate and multivariate survival analysis showed that advanced T stage, nodal metastasis, and strong VEGF intensity were independent adverse predictors for overall and disease-free survival. In stage IV disease, strong VEGF immunoreactivity was found to be the single adverse factor affecting the overall survival and a contributory factor for disease-free survival.ConclusionsVEGF immunoreactivity is a strong predictor of adverse outcome, particularly in locoregionally advanced disease.


Clinical Oncology | 1994

Patterns of early treatment failure in non-metastatic nasopharyngeal carcinoma: a study based on CT scanning.

K. H. Yu; Peter M.L. Teo; W.Y. Lee; Sing Fai Leung; Peter H.K. Choi; Philip J. Johnson

Six hundred and twenty-eight patients with non-metastatic nasopharyngeal carcinoma were staged by CT scanning and treated with radical locoregional radiotherapy. Parapharyngeal boost radiation for bulky parapharyngeal involvement, neoadjuvant chemotherapy for bulky nodal metastases, and intracavitary 192Ir treatment for local persistence of tumour after external radiotherapy were also used as appropriate. Forty-eight patients had Hos (1978) Stage I disease (7.6%), 167 Stage II (26.6%), 312 Stage III (49.7%) and 101 Stage IV (16.1%). At 2 years after treatment, 185 patients (29.5%) had developed recurrence; 112 had distant metastases (60.5%), and 75 had local failure (40.5%). Eighty-three patients had developed distant metastases alone, 73 patients locoregional failure alone and 29 patients had both locoregional and metastatic failure. The overall 2-year actuarial distant and local failure rates were 18.4% and 12.7% respectively. Distant metastasis is the major form of treatment failure which limits early survival. Seventy-four per cent of distant metastases were not associated with locoregional recurrence and had probably arisen from pre-existing occult foci. Our data also suggest that the advent of CT scanning has improved local tumour delineation and radiotherapy planning, and hence local control.


American Journal of Neuroradiology | 2013

T2-Weighted MR Imaging Early after Chemoradiotherapy to Evaluate Treatment Response in Head and Neck Squamous Cell Carcinoma

Ann D. King; C.K. Keung; K. H. Yu; F. Mo; Kunwar S. Bhatia; David K. W. Yeung; Gary M.K. Tse; Alexander C. Vlantis; Anil T. Ahuja

BACKGROUND AND PURPOSE: T2-weighted MRI shows potential in early posttreatment assessment of the primary tumor. Residual masses composed entirely of low T2-signal scar tissue suggest local control and those ≥1 cm of similar signal to untreated tumor suggest local failure. The purpose of this study was to investigate the diagnostic accuracy of T2-weighted MR imaging early after chemoradiotherapy for identifying primary tumor treatment failure in squamous cell carcinoma of the head and neck. MATERIALS AND METHODS: At 6 weeks after treatment, T2-weighted MR images of 37 primary tumors in 37 patients were assessed. Residual masses were divided into 3 patterns: pattern 1 = scar tissue only (flat-edged/retracted mass of low T2 signal intensity); pattern 2 = mass without features described in pattern 1 or 3; and pattern 3 = any pattern that included an expansile mass ≥1 cm of intermediate T2 signal intensity (similar grade of signal intensity to the untreated tumor). T2 patterns were analyzed for local outcome (Fisher exact test) and time to local failure (univariate and multivariate analysis of T2 pattern, age, T stage, and tumor size by use of the Cox regression model). RESULTS: Residual masses after treatment were present in 34 (92%) of 37 patients. Local failures occurred in residual masses with pattern 1 in 0 (0%) of 14 patients; pattern 2 in 6 (55%) of 11 patients; and pattern 3 in 9 (100%) of 9 patients. Significant associations were found between local control and pattern 1 (P = <.0001; sensitivity, 74%; specificity, 100%; PPV, 100%; NPV, 75%; accuracy, 85%), and between local failure and pattern 3 (P = <.0001; sensitivity, 60%; specificity, 100%; PPV, 100%; NPV, 76%; accuracy, 82%). Pattern 2 showed no significant associations with local outcome. Univariate analysis of time to local failure showed that the T2 pattern was significant (P < .0001) and remained significant on multivariate analysis. CONCLUSIONS: T2-weighted MR imaging is a potential tool for early posttreatment assessment of primary HNSCC treatment response. Awareness of correlation of the T2 pattern of any residual mass with treatment outcome at the primary site may contribute to patient treatment.


British Journal of Radiology | 2010

Does primary tumour volumetry performed early in the course of definitive concomitant chemoradiotherapy for head and neck squamous cell carcinoma improve prediction of primary site outcome

Kunwar S. Bhatia; Ann D. King; K. H. Yu; Alexander C. Vlantis; Gary M.K. Tse; Frankie Mo; Anil T. Ahuja

Although previous studies have documented correlations between pre-treatment or post-treatment primary tumour volumes and local outcome following definitive concomitant chemoradiotherapy (CCRT) in head and neck squamous cell carcinoma (HNSCC), no study has included and compared tumour volumes during CCRT. We reviewed the MRIs of 69 HNSCC patients treated with a 6 weeks course of CCRT and who underwent successful MRI pre-treatment (n = 69), 2 weeks intra-treatment (n = 48) and 6 weeks post-treatment (n = 61). Primary tumour volumes on MRI at the three time points were calculated and compared for their predictive value for primary site outcome. Volume thresholds optimised to predict failure with the highest accuracy and positive predictive value (PPV) were calculated. The mean pre-treatment volume was 24.6 cm³ (range, 1.1-187.9 cm³) and the mean follow-up interval was 41 months (range, 12-100 months). 23 primary tumours failed treatment (33%). Volumes before, during and after CCRT were positively associated with local failure (p = 0.015, p = 0.009, p<0.0001). Volume reductions during and after CCRT were negatively associated with local failure (p = 0.021, p = 0.001). Pre-treatment and intra-treatment volume thresholds achieved the highest accuracy and produced intermediate PPVs (51-64%) for predicting local failure. Optimised intra-treatment thresholds did not identify any more treatment failures than the pre-treatment thresholds. By comparison, a 6 weeks post-treatment volume reduction (<35%) achieved 100% PPV for failure, albeit with 26% sensitivity. In conclusion, primary tumour volumetry performed early in CCRT provides minimal additional information compared with pre-treatment volumetry, with respect to predicting post-treatment local failures. Therefore, volumetry during CCRT is unlikely to be useful for guiding individual response-based therapeutic modifications.


Clinical Oncology | 1995

Perineal Paget's Disease: Effective Treatment with Fractionated High Dose Rate Brachytherapy

W. H. Kwan; Peter M.L. Teo; Y.K. Ngar; K. H. Yu; Peter H.K. Choi

A patient with perineal extramammary Pagets disease is described. He was treated successfully with fractionated high dose rate brachytherapy.


Otolaryngology-Head and Neck Surgery | 2010

Correlation of biomarkers in head and neck squamous cell carcinoma

Gary M. Tse; Ann D. King; Alex M C Yu; Christopher C F Lam; Anthony W.H. Chan; George G. Chen; David K. W. Yeung; K. H. Yu; Kunwar S. Bhatia; Amy B.W. Chan

OBJECTIVE: To evaluate the relationship of functional magnetic resonance imaging (MRI) parameters, including choline/creatine ratio (Cho/Cr) and apparent diffusion coefficient (ADC) with protein expression of 10 common tumor and prognostic markers in head and neck squamous cell carcinoma. STUDY DESIGN: Cross-sectional study. SETTING: University hospital. SUBJECTS AND METHODS: The Cho/Cr and ADC obtained from 74 patients with head and neck squamous cell carcinoma were correlated with the expression level of the 10 protein markers as determined by immunohistochemistry. RESULTS: Cho/Cr showed significant positive correlations with cyclooxygenase 2 in primary tumors (r = 0.714), and epidermal growth factor receptor in metastatic cervical lymph nodes (r = 0.522). ADC showed significant (r = −0.591) negative correlation with human epidermal growth factor receptor 2 in metastatic cervical lymph nodes. CONCLUSION: There are relationships between protein and functional MRI markers. Future research in this direction may improve our understanding of the cancer micro-environment.


PLOS ONE | 2015

DCE-MRI for Pre-Treatment Prediction and Post-Treatment Assessment of Treatment Response in Sites of Squamous Cell Carcinoma in the Head and Neck.

Ann D. King; Steven Kwok Keung Chow; K. H. Yu; Frankie Mo; David K. W. Yeung; Jing Yuan; Benjamin King Hong Law; Kunwar S. Bhatia; Alexander C. Vlantis; Anil T. Ahuja

Background and Purpose It is important to identify patients with head and neck squamous cell carcinoma (SCC) who fail to respond to chemoradiotherapy so that they can undergo post-treatment salvage surgery while the disease is still operable. This study aimed to determine the diagnostic performance of dynamic contrast enhanced (DCE)-MRI using a pharmacokinetic model for pre-treatment predictive imaging, as well as post-treatment diagnosis, of residual SCC at primary and nodal sites in the head and neck. Material and Methods Forty-nine patients with 83 SCC sites (primary and/or nodal) underwent pre-treatment DCE-MRI, and 43 patients underwent post-treatment DCE-MRI, of which 33 SCC sites had a residual mass amenable to analysis. Pre-treatment, post-treatment and % change in the mean Ktrans, kep, ve and AUGC were obtained from SCC sites. Logistic regression was used to correlate DCE parameters at each SCC site with treatment response at the same site, based on clinical outcome at that site at a minimum of two years. Results None of the pre-treatment DCE-MRI parameters showed significant correlations with SCC site failure (SF) (29/83 sites) or site control (SC) (54/83 sites). Post-treatment residual masses with SF (14/33) had significantly higher kep (p = 0.05), higher AUGC (p = 0.02), and lower % reduction in AUGC (p = 0.02), than residual masses with SC (19/33), with the % change in AUGC remaining significant on multivariate analysis. Conclusion Pre-treatment DCE-MRI did not predict which SCC sites would fail treatment, but post-treatment DCE-MRI showed potential for identifying residual masses that had failed treatment.

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W. H. Kwan

The Chinese University of Hong Kong

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Anthony T.C. Chan

The Chinese University of Hong Kong

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Edwin P. Hui

The Chinese University of Hong Kong

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M. K. Kam

The Chinese University of Hong Kong

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Ann D. King

The Chinese University of Hong Kong

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Sing Fai Leung

The Chinese University of Hong Kong

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A.D. King

The Chinese University of Hong Kong

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Brigette Ma

The Chinese University of Hong Kong

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Frankie Mo

The Chinese University of Hong Kong

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Kunwar S. Bhatia

The Chinese University of Hong Kong

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