9 results on '"Nasopharyngeal cancer"'
Search Results
2. Evaluation of deformable image registration (DIR) methods for dose accumulation in nasopharyngeal cancer patients during radiotherapy
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Nobnop Wannapha, Chitapanarux Imjai, Neamin Hudsaleark, Wanwilairat Somsak, Lorvidhaya Vicharn, and Sanghangthum Taweap
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deformable image registration ,dose accumulation ,nasopharyngeal cancer ,mvct ,helical tomotherapy ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Deformable image registration (DIR) is used to modify structures according to anatomical changes for observing the dosimetric effect. In this study, megavoltage computed tomography (MVCT) images were used to generate cumulative doses for nasopharyngeal cancer (NPC) patients by various DIR methods. The performance of the multiple DIR methods was analysed, and the impact of dose accumulation was assessed.
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- 2017
- Full Text
- View/download PDF
3. The ratio of weight loss to planning target volume significantly impacts setup errors in nasopharyngeal cancer patients undergoing helical tomotherapy with daily megavoltage computed tomography
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Hou Wei-Hsien, Wang Chun-Wei, Tsai Chiao-Ling, Hsu Feng-Ming, and Cheng Jason Chia-Hsien
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nasopharyngeal cancer ,intensity-modulated radiotherapy ,setup errors ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Changes in head and neck anatomy during radiation therapy (RT) produce setup uncertainties of nasopharyngeal cancer (NPC) irradiation. We retrospectively analyzed image guidance data to identify clinical predictors of setup errors.
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- 2016
- Full Text
- View/download PDF
4. MRI to delineate the gross tumor volume of nasopharyngeal cancers: which sequences and planes should be used?
- Author
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Popovtzer Aron, Ibrahim Mohannad, Tatro Daniel, Feng Felix Y., Haken Randall K. Ten, and Eisbruch Avraham
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gross tumor volume ,mri ,nasopharyngeal cancer ,radiotherapy ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Background. Magnetic resonance imaging (MRI) has been found to be better than computed tomography for defining the extent of primary gross tumor volume (GTV) in advanced nasopharyngeal cancer. It is routinely applied for target delineation in planning radiotherapy. However, the specific MRI sequences/planes that should be used are unknown.
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- 2014
- Full Text
- View/download PDF
5. Prognostic value of plasma EBV DNA for nasopharyngeal cancer patients during treatment with intensity-modulated radiation therapy and concurrent chemotherapy
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Anussara Prayongrat, Sarin Kitpanit, Chakkapong Chakkabat, Pokrath Hansasuta, Danita Kannarunimit, and Chawalit Lertbutsayanukul
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0301 basic medicine ,medicine.medical_specialty ,Multivariate analysis ,prognosis during treatment ,medicine.medical_treatment ,plasma ebv ,nasopharyngeal cancer ,R895-920 ,Gastroenterology ,03 medical and health sciences ,Medical physics. Medical radiology. Nuclear medicine ,0302 clinical medicine ,Concurrent chemotherapy ,Internal medicine ,hemic and lymphatic diseases ,Post-hoc analysis ,medicine ,Radiology, Nuclear Medicine and imaging ,Nasopharyngeal cancer ,business.industry ,Hazard ratio ,Intensity-modulated radiation therapy ,imrt ,Treatment period ,Radiation therapy ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,business ,Research Article - Abstract
Background Plasma EBV DNA concentrations at the time of diagnosis (pre-EBV) and post treatment (post-EBV) have significant value for predicting the clinical outcome of nasopharyngeal cancer (NPC) patients. However, the prognostic value of the EBV concentration during radiation therapy (mid-EBV) has not been vigorously studied. Patients and methods This was a post hoc analysis of 105 detectable pre-EBV NPC patients from a phase II/III study comparing sequential (SEQ) versus simultaneous integrated boost (SIB) intensity-modulated radiation therapy (IMRT). Plasma EBV DNA concentrations were measured by PCR before commencement of IMRT, at the 5th week of radiation therapy and 3 months after the completion of IMRT. The objective was to identify the prognostic value of mid-EBV to predict overall survival (OS), progression-free survival (PFS) and distant metastasis-free survival (DMFS). Results A median pre-EBV was 6880 copies/ml. Mid-EBV and post-EBV were detectable in 14.3% and 6.7% of the patients, respectively. The median follow-up time was 45.3 months. The 3-year OS, PFS and DMFS rates were 86.0% vs. 66.7% (p = 0.043), 81.5% vs. 52.5% (p = 0.006), 86.1% vs. 76.6% (p = 0.150), respectively, for those with undetectable mid-EBV vs. persistently detectable mid-EBV. However, in the multivariate analysis, only persistently detectable post-EBV was significantly associated with a worse OS (hazard ratio (HR) = 6.881, 95% confident interval (CI) 1.699-27.867, p = 0.007), PFS (HR = 5.117, 95% CI 1.562–16.768, p = 0.007) and DMFS (HR = 129.071, 95%CI 19.031–875.364, p < 0.001). Conclusions Detectable post-EBV was the most powerful adverse prognostic factor for OS, PFS and DMFS; however, detectable mid-EBV was associated with worse OS, PFS especially Local-PFS (LPFS) and may facilitate adaptive treatment during the radiation treatment period.
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- 2018
6. Evaluation of deformable image registration (DIR) methods for dose accumulation in nasopharyngeal cancer patients during radiotherapy
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Vicharn Lorvidhaya, Taweap Sanghangthum, Imjai Chitapanarux, Hudsaleark Neamin, Somsak Wanwilairat, and Wannapha Nobnop
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medicine.medical_specialty ,medicine.medical_treatment ,nasopharyngeal cancer ,R895-920 ,Image registration ,Tomotherapy ,030218 nuclear medicine & medical imaging ,Medical physics. Medical radiology. Nuclear medicine ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Initial treatment ,Radiology, Nuclear Medicine and imaging ,deformable image registration ,Nasopharyngeal cancer ,Dose accumulation ,dose accumulation ,business.industry ,Cumulative dose ,mvct ,helical tomotherapy ,Target dose ,Radiation therapy ,Oncology ,030220 oncology & carcinogenesis ,Radiology ,Nuclear medicine ,business ,Research Article - Abstract
Introduction Deformable image registration (DIR) is used to modify structures according to anatomical changes for observing the dosimetric effect. In this study, megavoltage computed tomography (MVCT) images were used to generate cumulative doses for nasopharyngeal cancer (NPC) patients by various DIR methods. The performance of the multiple DIR methods was analysed, and the impact of dose accumulation was assessed. Patients and methods The study consisted of five NPC patients treated with a helical tomotherapy unit. The weekly MVCT images at the 1st, 6th, 11th, 16th, 21st, 26th, and 31st fractions were used to assess the dose accumulation by the four DIR methods. The cumulative dose deviations from the initial treatment plan were analysed, and correlations of these variations with the anatomic changes and DIR methods were explored. Results The target dose received a slightly different result from the initial plan at the end of the treatment. The organ dose differences increased as the treatment progressed to 6.8% (range: 2.2 to 10.9%), 15.2% (range: -1.7 to 36.3%), and 6.4% (range: -1.6 to 13.2%) for the right parotid, the left parotid, and the spinal cord, respectively. The mean uncertainty values to estimate the accumulated doses for all the DIR methods were 0.21 ± 0.11 Gy (target dose), 1.99 ± 0.76 Gy (right parotid), 1.19 ± 0.24 Gy (left parotid), and 0.41 ± 0.04 Gy (spinal cord). Conclusions Accuracy of the DIR methods affects the estimation of dose accumulation on both the target dose and the organ dose. The DIR methods provide an adequate dose estimation technique for observation as a result of inter-fractional anatomic changes and are beneficial for adaptive treatment strategies.
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- 2017
7. The outcome of the first 100 nasopharyngeal cancer patients in thailand treated by helical tomotherapy
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Wimrak Onchan, Dirk Van Gestel, Patumrat Sripan, Suwapim Janla-or, Bongkot Jia-Mahasap, Patcharawadee Kayan, Wannapha Nobnop, Patrinee Traisathit, Imjai Chitapanarux, Ekkasit Tharavichitkul, Pitchayaponne Klunklin, Ausareeya Chumachote, and Somvilai Chakrabandhu
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medicine.medical_treatment ,R895-920 ,Tomotherapy ,030218 nuclear medicine & medical imaging ,nasopharynx ,03 medical and health sciences ,Medical physics. Medical radiology. Nuclear medicine ,0302 clinical medicine ,Interquartile range ,medicine ,Mucositis ,cancer ,Radiology, Nuclear Medicine and imaging ,Imagerie médicale, radiologie, tomographie ,Nasopharyngeal cancer ,Chemotherapy ,business.industry ,helical tomotherapy ,Cancer ,medicine.disease ,Parotid gland ,Cancérologie ,medicine.anatomical_structure ,Oncology ,Nasopharyngeal carcinoma ,030220 oncology & carcinogenesis ,Nuclear medicine ,business ,Research Article - Abstract
The aim of the study was to analyse of two-year loco-regional failure free survival (LRFFS), distant metastasis free survival (DMFS), overall survival (OS), and toxicity outcomes of the first 100 nasopharyngeal carcinoma patients in Thailand treated by helical tomotherapy. Between March 2012 and December 2015, 100 patients with non-metastatic nasopharyngeal carcinoma were treated by helical tomotherapy. All patients were treated by platinum-based concurrent chemoradiotherapy and adjuvant or neo-adjuvant chemotherapy. The median age was 51 years (interquartile ranges [IQR]: 42.5-57.0). The mean ± SD of D95% of planning target volume (PTV) 70, 59.4 and 54 were 70.2 ± 0.5, 59.8 ± 0.6, and 54.3 ± 0.8 Gy, respectively. The mean ± SD of conformity index, and homogeneity index were 0.89 ± 0.13 and 0.06 ± 0.07. Mean ± SD of D2 % of spinal cord and brainstem were 34.1 ± 4.4 and 53.3 ±6.3 Gy. Mean ± SD of D50 of contralateral and ipsilateral parotid gland were 28.4 ± 6.7 and 38.5 ± 11.2 Gy. At a median follow-up of 33 months (IQR: 25-41), the 2-year LRFFS, DMFS, OS were 94% (95%CI: 87-98%), 96% (95% CI: 89-98%), and 99% (95% CI: 93-100%), respectively. Acute grade 3 dermatitis, pharyngoesophagitis, and mucositis occurred in 5%, 51%, and 37%, respectively. Late pharyngoesophagitis grade 0 and 1 were found in 98% and 2% of patients. Late xerostomia grade 0, 1 and 2 were found in 17%, 78% and 5%, respectively. Helical tomotherapy offers good dosimetric performance and achieves excellent treatment outcome in nasopharyngeal carcinoma patients., SCOPUS: ar.j, info:eu-repo/semantics/published
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- 2017
8. The ratio of weight loss to planning target volume significantly impacts setup errors in nasopharyngeal cancer patients undergoing helical tomotherapy with daily megavoltage computed tomography
- Author
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Chiao-Ling Tsai, Feng-Ming Hsu, Chun-Wei Wang, Jason Chia-Hsien Cheng, and Wei-Hsien Hou
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Body frame ,medicine.medical_specialty ,medicine.medical_treatment ,R895-920 ,nasopharyngeal cancer ,Planning target volume ,Tomotherapy ,030218 nuclear medicine & medical imaging ,Medical physics. Medical radiology. Nuclear medicine ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,Tumor stage ,otorhinolaryngologic diseases ,medicine ,natural sciences ,Radiology, Nuclear Medicine and imaging ,Nasopharyngeal cancer ,business.industry ,technology, industry, and agriculture ,equipment and supplies ,intensity-modulated radiotherapy ,Radiation therapy ,Oncology ,030220 oncology & carcinogenesis ,biological sciences ,Radiology ,Megavoltage Computed Tomography ,medicine.symptom ,Nuclear medicine ,business ,Research Article ,setup errors - Abstract
Background Changes in head and neck anatomy during radiation therapy (RT) produce setup uncertainties of nasopharyngeal cancer (NPC) irradiation. We retrospectively analyzed image guidance data to identify clinical predictors of setup errors. Patients and methods The data of 217 NPC patients undergoing definitive RT on a helical tomotherapy (HT) unit were analyzed. Factors including tumor stage, body mass index, weight loss, and planning target volume (PTV) were assessed as predictors of daily megavoltage computed tomography (MVCT) setup displacements, which were automatically registered using software. Results Mean daily setup displacements (in mm) were 1.2 ± 0.6, 1.8 ± 0.8, 3.4 ± 1.4 in the medial-lateral (ML), superior-inferior (SI), and anterior-posterior (AP) directions, respectively. Mean weight loss was 4.6 ± 3.3 kg (6.8 ± 4.9%). Patients with weight loss > 5% had significantly larger setup displacements in the AP (3.6 ± 1.5 vs. 2.9 ± 1.1 mm, p < 0.001) and SI (1.6 ± 0.7 vs. 1.9 ± 0.9 mm, p = 0.01) direction, but not in the ML direction (p = 0.279). The AP setup error increased 0.06 mm (y = 0.055x + 2.927, x: percentage of weight loss/PTV, y: AP displacement) per one percent increase in weight loss normalized to PTV. Conclusions Patients with weight loss > 5% and smaller PTVs, possibly because of small body frame or neck girth, were more likely to have increased setup errors in the AP direction.
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- 2016
9. MRI to delineate the gross tumor volume of nasopharyngeal cancers: which sequences and planes should be used?
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Avraham Eisbruch, Randall K. Ten Haken, Felix Y. Feng, Mohannad Ibrahim, Aron Popovtzer, and D. Tatro
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gross tumor volume ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Planning target volume ,nasopharyngeal cancer ,R895-920 ,Magnetic resonance imaging ,Sagittal plane ,Gross tumor volume ,Plane (Unicode) ,Radiation therapy ,Medical physics. Medical radiology. Nuclear medicine ,medicine.anatomical_structure ,Oncology ,Coronal plane ,medicine ,Radiology, Nuclear Medicine and imaging ,Nuclear medicine ,business ,mri ,radiotherapy ,Nasopharyngeal cancer ,Research Article - Abstract
Background. Magnetic resonance imaging (MRI) has been found to be better than computed tomography for defining the extent of primary gross tumor volume (GTV) in advanced nasopharyngeal cancer. It is routinely applied for target delineation in planning radiotherapy. However, the specific MRI sequences/planes that should be used are unknown. Methods. Twelve patients with nasopharyngeal cancer underwent primary GTV evaluation with gadolinium-enhanced axial T1 weighted image (T1) and T2 weighted image (T2), coronal T1, and sagittal T1 sequences. Each sequence was registered with the planning computed tomography scans. Planning target volumes (PTVs) were derived by uniform expansions of the GTVs. The volumes encompassed by the various sequences/planes, and the volumes common to all sequences/planes, were compared quantitatively and anatomically to the volume delineated by the commonly used axial T1-based dataset. Results. Addition of the axial T2 sequence increased the axial T1-based GTV by 12% on average (p = 0.004), and composite evaluations that included the coronal T1 and sagittal T1 planes increased the axial T1-based GTVs by 30% on average (p = 0.003). The axial T1-based PTVs were increased by 20% by the additional sequences (p = 0.04). Each sequence/plane added unique volume extensions. The GTVs common to all the T1 planes accounted for 38% of the total volumes of all the T1 planes. Anatomically, addition of the coronal and sagittal-based GTVs extended the axial T1-based GTV caudally and cranially, notably to the base of the skull. Conclusions. Adding MRI planes and sequences to the traditional axial T1 sequence yields significant quantitative and anatomically important extensions of the GTVs and PTVs. For accurate target delineation in nasopharyngeal cancer, we recommend that GTVs be outlined in all MRI sequences/planes and registered with the planning computed tomography scans.
- Published
- 2014
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