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You JHS, Cho WCS, Li YC, Kwan CK, Au JSK. Health economic analysis of epidermal growth factor receptor mutation-guided first-line therapies for advanced non-small-cell lung cancer: abridged secondary publication. Hong Kong Med J 2023; 29 Suppl 2:8-11. [PMID: 36950997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2023] Open
Affiliation(s)
- J H S You
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - W C S Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong SAR, China
| | - Y C Li
- Hong Kong United Oncology Centre, Hong Kong SAR, China
| | - C K Kwan
- Department of Oncology, United Christian Hospital, Hong Kong SAR, China
| | - J S K Au
- Oncology Center, Hong Kong Adventist Hospital, Hong Kong SAR, China
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Chow TL, Kwan WW, Kwan CK. Treatment of cutaneous angiosarcoma of the scalp and face in Chinese patients: local experience at a regional hospital in Hong Kong. Hong Kong Med J 2018; 24:25-31. [PMID: 29326400 DOI: 10.12809/hkmj176813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION Angiosarcoma is a rare aggressive sarcoma that occurs mostly in the skin of the head and neck in the elderly population. The optimal management is dubious and most studies are from Caucasian populations. We aimed to examine the treatment and outcome of this disease in Chinese patients. METHODS Data of patients with histopathologically verified cutaneous angiosarcoma of the head and neck during December 1997 to September 2016 were retrieved from our hospital cancer registry. The demographic data, clinicopathological information, modality of treatment, and outcomes were reviewed. RESULTS During the study period, 17 Chinese patients were treated. Their median age was 81 years. The tumours were present in the scalp only (n=11), face only (n=4), or both scalp and face (n=2). Only two patients had distant metastases. The modalities of treatment were surgery (n=6), surgery and adjuvant radiotherapy (n=1), palliative radiotherapy (n=5), or palliative chemotherapy (n=3). The remaining two patients refused any treatment initially. Of the seven patients treated surgically, there were four local and two regional recurrences. The median time to relapse was 7.5 months. Overall, 16 patients had died; causes of death were disease-related in 12 whereas four other patients died of inter-current illnesses. One patient was still living with the disease. The median overall survival was 11.1 months and the longest overall survival was 42 months. CONCLUSION The outcome of angiosarcoma in our series is poor. A high index of suspicion is mandatory for prompt diagnosis. Adjuvant radiotherapy is recommended following surgery. The benefit and role of systemic treatment in various combinations with surgery or radiotherapy require further study.
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Affiliation(s)
- T L Chow
- Head and Neck Division, Department of Surgery, United Christian Hospital, Kwun Tong, Hong Kong
| | - W Wy Kwan
- Head and Neck Division, Department of Surgery, United Christian Hospital, Kwun Tong, Hong Kong
| | - C K Kwan
- Department of Oncology, United Christian Hospital, Kwun Tong, Hong Kong
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Kwan CK, Al-Samarrai T, Smith LC, Sabharwal CJ, Valente KA, Torian LV, McMurdo LM, Shepard CW, Brooks JT, Kuehnert MJ. HIV Screening Practices for Living Organ Donors, New York State, 2010: Need for Standard Policies. Clin Infect Dis 2012; 55:990-5. [DOI: 10.1093/cid/cis555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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Chi I, Law BVKK, Leung ACT, Liu CP, Yeoh CS, Cheng YH, Ma AMK, Kwan CK, Lai C. Residential Assessment Instrument 2.0 in care planning for residents in nursing homes. Hong Kong Med J 2010; 16 Suppl 3:29-33. [PMID: 20601731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Affiliation(s)
- I Chi
- School of Social Work and School of Gerontology, University of Southern California, United States.
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Chan Y, Tang WYM, Lam WY, Loo SKF, Li SPS, Au AWM, Leung WY, Kwan CK, Lo KK. A cluster of chilblains in Hong Kong. Hong Kong Med J 2008; 14:185-191. [PMID: 18525086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
OBJECTIVE To report a recent clustering of chilblain cases in Hong Kong. DESIGN Case series. SETTING A regional hospital and a social hygiene clinic in the New Territories West, Hong Kong. PATIENTS Patients with a clinical diagnosis of chilblains in February 2008. RESULTS Eleven patients with chilblains were identified; seven (64%) gave an antecedent history of prolonged exposure to cold. They all presented with erythematous or dusky erythematous skin lesions affecting the distal extremities, especially fingers and toes. Laboratory tests revealed elevated antinuclear antibodies titres in two, positive rheumatoid factor in two, presence of cold agglutinins in one, and a raised anti-DNA titre (>300 IU/mL) in one. Skin biopsies were performed in six patients, four of them showed typical histopathological features of chilblains. In the patient with systemic lupus erythematosus, features of vasculitis were suspected, and in the one with pre-existing juvenile rheumatoid arthritis, there were features of livedo vasculitis. In 10 (91%) of the patients, the skin lesions had resolved when they were last assessed (at the end of March 2008), but had persisted in the patient who had pre-existing systemic lupus erythematosus. CONCLUSION The recent clustering of chilblains was possibly related temporally to the prolonged cold weather at the end of January to mid-February. In our series, most of the patients developed chilblains as an isolated condition and resolved spontaneously within a few weeks. Laboratory tests and skin biopsies for chilblains are not necessary, unless the condition persists, the diagnosis in doubt or an underlying systemic disease is suspected.
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Affiliation(s)
- Y Chan
- Department of Medicine and Geriatrics, Tuen Mun Hospital, Tuen Mun, Hong Kong
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Ngan RK, Yiu HY, Cheng HC, Kwan CK, Lam TW, Tsang D, Kwok P, Cheng WW, Au KH, Wong KH, Yip TC. Preemptive versus deferred lamivudine in preventing chemotherapy (CT) interruptions in hepatitis B (HBV) carriers with non-hematological malignancy—preliminary report of a randomized phase III study. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.lba19684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
LBA19684 Background: About 10% cancer patients (pts) are HBV carriers in endemic areas, who have a risk of HBV reactivation with CT preventable by Lamivudine (Lam). Methods: Pts seropositive for HBV surface antigen (HBsAg+) planned to receive ≥ 4 cycles of CT for non-hematological malignancy were randomized to receiving either preemptive Lam during and for 8 weeks after CT (arm I), or observation only and deferred Lam at biochemical hepatitis reactivation (arm II). All pts had normal liver enzymes & clotting profiles, age 18–75 & KPS >50 before entry. Serial clotting profile, liver enzyme and HBV DNA levels were monitored during CT and for 15 weeks post-CT. The endpoints include % of CT interruptions due to HBV reactivation (primary), HBV reactivation %, CT drug dose intensity levels & HBV reactivation-free survival (all secondary). 110 pts are estimated to give a power of 90% to detect the projected difference in the primary endpoint at 2-sided alpha error of 0.05. Results: Pt accrual was completed in 1/07. As at 3/07, 92 (81%) of the 114 pts randomized have completed the study or died, and were included for analysis. Breast & lung cancer constituted 71% of the cancers. There was no statistical difference in pt, cancer, CT, or viral characteristics between the 2 arms. Results are summarized in table . All 4 pts with CT interruptions and 11/14 pts with HBV reactivation had breast cancer. No difference in CT drug dose intensity levels was observed. Steroid used in the anti-emetic regimen was a significant factor in predicting viral reactivation in arm II pts in multivariate analysis. Conclusions: Although the incidence of CT interruptions was low in unselected pts without preemptive Lam, it was much higher in breast cancer pts despite deferred Lam, who also had significant rates of biochemical hepatitis & viral reactivation. Preemptive Lam should be given to breast cancer pts, & considered in other cancer pts receiving CT who are HBsAg+. [Table: see text] No significant financial relationships to disclose.
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Affiliation(s)
- R. K. Ngan
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - H. Y. Yiu
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - H. C. Cheng
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - C. K. Kwan
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - T. W. Lam
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - D. Tsang
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - P. Kwok
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - W. W. Cheng
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - K. H. Au
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - K. H. Wong
- Queen Elizabeth Hospital, Hong Kong SAR, China
| | - T. C. Yip
- Queen Elizabeth Hospital, Hong Kong SAR, China
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Kwan LK, Lam AK, Kwan CK, Yeung PH. The characteristics of near prism induced fixation disparity curve in Hong Kong Chinese. Ophthalmic Physiol Opt 1999; 19:393-400. [PMID: 10768020 DOI: 10.1046/j.1475-1313.1999.00456.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The characteristics of prism induced fixation disparity curve at near were studied in 56 asymptomatic young adult Hong Kong Chinese (average age 21 years). The percentage distribution of types of fixation disparity curves was found to be similar to some previous studies, with a higher prevalence of Type I curve (64.3%), followed by Type II (28.6%) and Type III (7.1%) curves. No Type IV curve was revealed from the sample. Two modified measurement approaches were applied to study the effect of measurement techniques on the parameters of fixation disparity curve obtained. A thorough description of the techniques was given. Although a significant difference in the x- and y-intercepts was obtained between different methods, the curve type and slope were not affected. The average y-intercepts (fixation disparity) were 2.72 min of arc and 3.54 min of arc from two methods respectively. Forty-one subjects had x-intercept (associated phoria) found from the curve. The average values were 2.42 delta base-out and 3.54 delta base-out from two methods respectively.
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Affiliation(s)
- L K Kwan
- Department of Optometry and Radiography, Hong Kong Polytechnic University, Kowloon, Hong Kong
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Kwan CK, Taylor GW. Optimization of the parallelogrammic grating diffraction efficiency for normally incident waves. Appl Opt 1998; 37:7698-7707. [PMID: 18301606 DOI: 10.1364/ao.37.007698] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The diffraction directivity of parallelogrammic gratings with second-order pitch is examined for a plane wave normally incident upon a corrugated waveguide structure. The three diffracted components are assumed to be in the form of guided waves, which permits a self-consistent calculation. The efficiencies of diffraction into the horizontal components are obtained. Also, the dependence of efficiency on grating thickness, waveguide thickness, grating pitch, and angle of inclination is determined. The approach provides a useful simulation tool for optimizing the design parameters for waveguide couplers with an orthogonal source.
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Ausubel LJ, Kwan CK, Sette A, Kuchroo V, Hafler DA. Complementary mutations in an antigenic peptide allow for crossreactivity of autoreactive T-cell clones. Proc Natl Acad Sci U S A 1996; 93:15317-22. [PMID: 8986809 PMCID: PMC26402 DOI: 10.1073/pnas.93.26.15317] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/1996] [Accepted: 10/04/1996] [Indexed: 02/03/2023] Open
Abstract
T cells recognize antigen by formation of a trimolecular complex in which the T-cell receptor (TCR) recognizes a specific peptide antigen within the groove of a major histocompatibility complex (MHC) molecule. It has generally been assumed that T-cell recognition of two distinct MHC-antigen complexes is due to similarities in the three-dimensional structure of the complexes. Here we report results of experiments examining the crossreactivity of TCRs recognizing the myelin basic protein peptide MBPp85-99 and several of its analogs in the context of MHC. We demonstrate that single conservative amino acid substitutions of the antigenic peptide at the predominant TCR contact residues at positions 91 and 93 totally abrogate reactivity of specific T-cell clones. Yet, when a conservative substitution is made at position 91 concomitant with a substitution at position 93, the T-cell clones regain reactivity equivalent with that of the original stimulating peptide. Thus, the exact nature of the amino acid side chains engaging one TCR functional pocket may change the apparent selectivity of the other predominant TCR functional pocket, thus suggesting a remarkable degree of receptor plasticity. This ability of the TCR-MHC-peptide complex to undergo conformational changes provides a conceptual framework for reconciling the apparent paradox of the extreme selectivity of the TCR and its remarkable crossreactivity with different MHC-peptide complexes.
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Affiliation(s)
- L J Ausubel
- Laboratory of Molecular Immunology, Brigham and Women's Hospital, Boston, MA, USA
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Surdutovich A, Jiang J, Kauppila WE, Kwan CK, Stein TS, Zhou S. Measurements of positronium-formation cross sections for positrons scattered by Rb atoms. Phys Rev A 1996; 53:2861-2864. [PMID: 9913203 DOI: 10.1103/physreva.53.2861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Kauppila WE, Dou L, Kwan CK, Przybyla D, Stein TS. Evidence for resonance and absorption effects in positron-atom differential elastic scattering. ACTA ACUST UNITED AC 1994. [DOI: 10.1007/bf02064504] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Zhou S, Parikh SP, Kauppila WE, Kwan CK, Lin D, Surdutovich A, Stein TS. Measurements of positronium formation cross sections for positron scattering by K, Na, and Ar atoms. Phys Rev Lett 1994; 73:236-239. [PMID: 10057119 DOI: 10.1103/physrevlett.73.236] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Zhou S, Kauppila WE, Kwan CK, Stein TS. Measurements of total cross sections for positrons and electrons colliding with atomic hydrogen. Phys Rev Lett 1994; 72:1443-1446. [PMID: 10055610 DOI: 10.1103/physrevlett.72.1443] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Parikh SP, Kauppila WE, Kwan CK, Lukaszew RA, Przybyla D, Stein TS, Zhou S. Toward measurements of total cross sections for positrons and electrons scattered by potassium and rubidium atoms. Phys Rev A 1993; 47:1535-1538. [PMID: 9909085 DOI: 10.1103/physreva.47.1535] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Dou L, Kauppila WE, Kwan CK, Przybyla D, Smith SJ, Stein TS. Evidence for resonances and absorption effects in positron-krypton differential-elastic-scattering measurements. Phys Rev A 1992; 46:R5327-R5330. [PMID: 9908886 DOI: 10.1103/physreva.46.r5327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Dou L, Kauppila WE, Kwan CK, Stein TS. Observation of structure in intermediate-energy positron-argon differential elastic scattering. Phys Rev Lett 1992; 68:2913-2916. [PMID: 10045527 DOI: 10.1103/physrevlett.68.2913] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Kwan CK, Kauppila WE, Lukaszew RA, Parikh SP, Stein TS, Wan YJ, Dababneh MS. Total cross-section measurements for positrons and electrons scattered by sodium and potassium atoms. Phys Rev A 1991; 44:1620-1635. [PMID: 9906128 DOI: 10.1103/physreva.44.1620] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Smith SJ, Hyder GM, Kauppila WE, Kwan CK, Stein TS. Evidence for absorption effects in positron elastic scattering by argon. Phys Rev Lett 1990; 64:1227-1230. [PMID: 10041340 DOI: 10.1103/physrevlett.64.1227] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Kwan CK, Hsieh Y, Kauppila WE, Smith SJ, Stein TS, Uddin MN, Dababneh MS. Erratum: e+/--CO and e+/--CO2 total cross-section measurements. Phys Rev A Gen Phys 1989; 39:2752. [PMID: 9920582 DOI: 10.1103/physreva.39.2752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Dababneh MS, Hsieh Y, Kauppila WE, Kwan CK, Smith SJ, Stein TS, Uddin MN. Total-cross-section measurements for positron and electron scattering by O2, CH. Phys Rev A Gen Phys 1988; 38:1207-1216. [PMID: 9900493 DOI: 10.1103/physreva.38.1207] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Hyder GM, Dababneh MS, Hsieh Y, Kauppila WE, Kwan CK, Mahdavi-Hezaveh M, Stein TS. Positron differential elastic-scattering cross-section measurements for argon. Phys Rev Lett 1986; 57:2252-2255. [PMID: 10033675 DOI: 10.1103/physrevlett.57.2252] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Stein TS, Gomez RD, Hsieh Y, Kauppila WE, Kwan CK, Wan YJ. Total cross-section measurements for positrons and electrons colliding with potassium. Phys Rev Lett 1985; 55:488-491. [PMID: 10032366 DOI: 10.1103/physrevlett.55.488] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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