Daniel T.T. Chua
University of Hong Kong
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Journal of Clinical Oncology | 2005
Anne W.M. Lee; W. H. Lau; Stewart Y. Tung; Daniel T.T. Chua; Rick Chappell; L. Xu; Lillian L. Siu; W.M. Sze; To-Wai Leung; Jonathan S. T. Sham; Roger K.C. Ngan; Stephen C.K. Law; T.K. Yau; Joseph Sk Au; Brian O'Sullivan; Ellie S.Y. Pang; Gordon K.H. Au; Joseph Lau
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.
Cancer | 1998
Daniel T.T. Chua; Jonathan S.T. Sham; D. Choy; Virchan Lorvidhaya; Yupa Sumitsawan; Sumitra Thongprasert; Visoot Vootiprux; Arkom Cheirsilpa; Tahir Azhar; Ary H. Reksodiputro
The aim of this trial was to compare the outcome achieved with neoadjuvant chemotherapy followed by radiotherapy to that achieved with radiotherapy alone for patients with locoregionally advanced undifferentiated or poorly differentiated nasopharyngeal carcinoma (NPC) meeting one of the following criteria: Hos T3 disease, Hos N2‐N3 disease, or lymph node size ≥3 cm.
Journal of Clinical Oncology | 2004
Dora L.W. Kwong; Jonathan S.T. Sham; Gordon K.H. Au; Daniel T.T. Chua; Philip W.K. Kwong; Ashley C. K. Cheng; P.M. Wu; Martin Law; Carol Kwok; C. C. Yau; Koon-Yat Wan; Raymond Tsz-Tong Chan; Damon D.K. Choy
PURPOSE To study the efficacy of concurrent chemoradiotherapy (CRT) and adjuvant chemotherapy (AC) for nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS Patients with Hos stage T3 or N2/N3 NPC or neck node > or = 4 cm were eligible. Patients were randomly assigned to have radiotherapy (RT) or CRT with uracil and tegafur and to have AC or no AC after RT/CRT. AC comprised alternating cisplatin, fluorouracil, vincristine, bleomycin, and methotrexate for six cycles. There were four treatment groups: A, RT; B, CRT; C, RT and AC; D, CRT and AC. For CRT versus RT, groups B and D were compared with groups A and C. For AC versus no AC, groups C and D were compared with groups A and B. RESULTS Three-year failure-free survival (FFS) and overall survival (OS) for CRT versus RT were 69.3% versus 57.8% and 86.5% versus 76.8%, respectively (P =.14 and.06; n = 110 v 109). Distant metastases rate (DMR) was significantly reduced with CRT (14.8% v 29.4%; P =.026). Locoregional failure rates (LRFR) were similar (20% v 27.6%; P =.39). Three-year FFS and OS for AC versus no AC were 62.5% versus 65% and 80.4% versus 83.1%, respectively (P =.83 and.69; n = 111 v 108). DMR and LRFR were not reduced with AC (P =.34 and.15, respectively). Cox model showed CRT to be a favorable prognostic factor for OS (hazard ratio, 0.42; P =.009). CONCLUSION An improvement in OS with CRT was observed but did not achieve statistical significance. The improvement seemed to be associated with a significant reduction in DMR. AC did not improve outcome.
Cancer | 2004
Dora L.W. Kwong; Edmond H.N. Pow; Jonathan S.T. Sham; Anne S. McMillan; Lucullus H.T. Leung; W. Keung Leung; Daniel T.T. Chua; Ashley C. K. Cheng; Po M. Wu; Gordon K.H. Au
Xerostomia is a uniform complication after radiotherapy (RT) for nasopharyngeal carcinoma (NPC). Dosimetric studies suggested that intensity‐modulated RT (IMRT) can spare part of the parotid glands from high‐dose radiation. Disease control and salivary function after IMRT for early‐stage NPC was studied prospectively.
International Journal of Radiation Oncology Biology Physics | 1997
Daniel T.T. Chua; Jonathan S.T. Sham; Dora L.W. Kwong; K.S. Tai; P.M. Wu; Maggie Lo; Annie Yung; D. Choy; Lilian Leong
PURPOSE To investigate the variability of tumor volume in nasopharyngeal carcinoma using quantitative measurements of tumor bulk derived from computed tomography, and to study the prognostic value of tumor volume in comparison with other variables. METHODS AND MATERIALS Two hundred ninety patients with newly diagnosed nasopharyngeal carcinoma were included in the study. The primary tumor volume (PTV) and nodal tumor volume (NTV) were obtained by outlining the tumor contour followed by summation of areas in sequential pretreatment computed tomography axial scans. Total tumor volume (TTV) was obtained by adding the PTV and NTV. All patients had radiotherapy as the primary treatment, 67 patients also received cisplatin-based neoadjuvant chemotheraphy. RESULTS A large variation in tumor volume was observed, especially in advanced stage disease. The median PTV (cc) in Hos T1, T2, and T3 disease were: 6.9 (range: 0.9-42.7), 18.8 (1.6-127.9), and 52.4 (3.3-166.8). The median TTV (cc) in Hos stage I to IV disease were: 7.6 (range: 1.3-42.7), 19.8 (3.2-55.7), 40.7 (4.1-222.7), and 51.1 (3.1-274.7). Patients with a large PTV (>60 cc) were associated with significantly poorer local control (5-year local control rate: 56%) and disease-specific survival (5-year survival rate: 53%). In patients with a small PTV (< or =20 cc), there were no significant differences in local control among different T stages. Large NTV (>30 cc) was associated with significantly higher distant failure rate (5-year distant relapse-free survival rate: 54%) and lower disease-specific survival (5-year survival rate: 40%). In multivariate analysis, only PTV was found to be an independent factor in predicting local control. CONCLUSION A large variation of tumor volume was present in different T stage disease of nasopharyngeal carcinoma, and PTV represents an independent prognostic factor of local control that appears to be more predictive than Hos T stage classification.
Journal of the National Cancer Institute | 2010
Anne W.M. Lee; Stewart Y. Tung; Daniel T.T. Chua; Roger K.C. Ngan; Rick Chappell; Raymond Tung; Lillian L. Siu; Wing-Fung Ng; Wing-Kin Sze; Gordon K.H. Au; Stephen C.K. Law; Brian O'Sullivan; T.K. Yau; To-Wai Leung; Joseph S. K. Au; W.M. Sze; Cheuk-Wai Choi; K. K. Fung; Joseph Lau; W. H. Lau
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.
Journal of Clinical Oncology | 2004
Daniel T.T. Chua; Jun Ma; Jonathan S.T. Sham; Hai Qiang Mai; D. Choy; Ming Huang Hong; Tai Xiang Lu; Hua Qing Min
5524 Background: To evaluate the long-term treatment outcome in patients with advanced stage nasopharyngeal carcinoma (NPC) treated by cisplatin-based induction chemotherapy and radiotherapy (CRT) versus radiotherapy alone (RT). METHODS The updated records of two previously reported phase III studies (the Asian-Oceania Clinical Oncology Association trial and the Guangzhou trial). testing the benefit of adding induction chemotherapy to radiotherapy in NPC were reviewed and the data were pooled together for analysis. A total of 784 patients were included for analysis, with equal number of patients in both the CRT and RT arms. The induction chemotherapy consisting of 2-3 cycles of cisplatin 100 mg/m2 day 1, bleomycin 10 mg/m2 day 1 & 5, and fluorouracil 800 mg/m2 day 1-5, or cisplatin 60 mg/m2 day 1 and epirubicin 110 mg/m2 day 1. Radiotherapy was given to the nasopharynx and neck using megavoltage radiation, with a median dose of 70 Gy. Treatment compliance was 92.6% in the CRT arm and 98% in the RT arm. The median follow-up time for surviving patients was 67 months. Analysis was done by intention to treat. RESULTS The addition of induction chemotherapy to radiotherapy was associated with a decrease in relapse by 14.3% and cancer deaths by 12.9% at 5 years. The 5-year relapse-free survival rate was 50.9% in the CRT arm and 42.7% in the RT arm (p=0.014), and the 5-year disease-specific survival rate was 63.5% in the CRT arm and 58.1% in the RT arm (p=0.029). The median disease-specific survival was not yet reached in the CRT arm and it was 82 months in the RT arm. The incidence of loco-regional failure and distant metastases were reduced by 18.3% and 13.3% at 5 years respectively with induction chemotherapy. There was no significant difference in the failure patterns between the 2 arms. CONCLUSIONS The addition of cisplatin-based induction chemotherapy to radiotherapy was associated with a modest but significant improvement in survival in advanced stage NPC. No significant financial relationships to disclose.
International Journal of Radiation Oncology Biology Physics | 1996
Dora L.W. Kwong; William I. Wei; Jonathan S.T. Sham; Wai-Kuen Ho; P. W. Yuen; Daniel T.T. Chua; Dennis Kin Kwok Au; P.M. Wu; D. Choy
PURPOSE The pattern of sensorineural hearing loss (SNHL) after primary treatment for nasopharyngeal carcinoma (NPC) was studied, and the effect of cisplatin, radiotherapy does, and fractionation were evaluated. METHODS AND MATERIALS One hundred thirty-two patients, 227 ears, and 1100 audiogram reports were analyzed. Radiotherapy dose ranged from 59.5 to 76.5 Gy. Fifty-two patients received preirradiation cisplatin, total dose 100-185 mg/m(2). Serial postirradiation bone conduction thresholds at 0.5 kHz, 1 kHz, 2 kHz, and 4 kHz were compared with pretreatment thresholds at respective frequencies. Increase of at least 15 dB was considered as significant and was further grouped as transient or persistent SNHL. Univariate and multivariate analyses were performed to identify predicting factors for persistent SNHL. RESULTS At median follow-up of 30 months, 24.2% of ears developed persistent SNHL. High frequency was more affected than low frequencies, 22 vs. 5.3%. Males were more affected than females, 29.4 vs. 15.5%, p = 0.0132. Incidence of persistent SNHL increased with age, with 0, 17.2, and 37.4% of patients aged under 30, between 30-50 and over 50 affected, respectively, p = 0.0001. High incidence was found in patient with postirradiation serous otitis media (SOM), 46.9%. Chemotherapy with cisplatin and radiation dose or fractionation had no significant effect. Multivariate analysis confirmed age, sex, and postirradiation SOM as significant prognostic factors for persistent SNHL. CONCLUSIONS Transient and persistent SNHL occurred after radiotherapy, more commonly affecting high frequency. A low dose of preirradiation cisplatin did not increase the risk. A dose fractionation effect of radiotherapy was not confirmed in this study.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2005
Kwok Hung Yu; Sing Fai Leung; Stewart Y. Tung; Benny Zee; Daniel T.T. Chua; Wai Man Sze; Stephen C.K. Law; Michael K.M. Kam; To Wai Leung; Jonathan S.T. Sham; Anne W.M. Lee; Joseph Sk Au; Edwin P. Hui; Wing Kin Sze; Ashley C. K. Cheng; T.K. Yau; Roger K.C. Ngan; Frank C.S. Wong; Gordon K.H. Au; Anthony T.C. Chan
The purpose of this article is to report the overall survival (OS) outcome of patients with nasopharyngeal carcinoma (NPC) with local failure who received salvage treatment and to identify prognostic factors for OS.
International Journal of Radiation Oncology Biology Physics | 1998
Daniel T.T. Chua; Jonathan S.T. Sham; Dora L.W. Kwong; William I. Wei; Gordon K.H. Au; D. Choy
PURPOSE To study the treatment outcome in patients with locally recurrent nasopharyngeal carcinoma as restaged by computed tomography (CT). PATIENTS AND METHODS One hundred forty patients with CT restaged locally recurrent nasopharyngeal carcinoma were reviewed. Patients were restaged at recurrence according to the AJCC stage classification with the following distribution: T1-T2:30%, T3:19%, T4:51%. Ninety-seven patients received reirradiation; among these 62 had external irradiation, 34 had brachytherapy, and 1 had both. Twelve patients received surgery. Thirty-one patients were treated with palliative intent and received either chemotherapy or supportive treatment only. Overall survival (OAS) and performance-adjusted survival (PAS, defined as surviving with a Karnofsky performance score [KPS] > 50) were calculated by Kaplan-Meier method. Multivariate analysis was performed using the Cox model. RESULTS The median survival for all patients was 23.8 months. After reirradiation, the 3-yr and 5-yr OAS rates were 46% and 36%, respectively. The corresponding PAS rates were 40% and 28%. The 3-yr OAS rates for recurrent T1-2, T3, and T4 disease after reirradiation were 71%, 42%, and 30%; the corresponding 5-yr OAS rates were 57%, 42%, 17%. The 3-yr and 5-yr OAS rates in patients receiving palliative treatments only were 19% and 0%, respectively. The 3-yr OAS rate after surgery was 42%. In the multivariate analysis, older age, recurrent T3-4 disease, and palliative treatment were unfavorable factors in predicting overall survival, whereas recurrent T3-4 disease, baseline KPS < 70, and palliative treatment were unfavorable factors in predicting PAS. A high complication rate was observed after reirradiation, with 34% of patients developing neurological sequel. CONCLUSION Aggressive treatment for locally recurrent nasopharyngeal carcinoma is warranted especially for those with disease confined to the nasopharynx. Survival after retreatment for more extensive disease remains poor but was still superior to supportive treatment only. Early diagnosis of local recurrence allows prompt administration of treatment and is associated with better outcome. Future studies should aim at improving the therapeutic ratio in the retreatment of recurrent disease especially in patients with more extensive local recurrence.