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Objective To investigate the effects of numerous re-planning strategies on the anatomic and dosimetric outcomes of target volume and organs at risk (OARs) in patients with head and neck cancer receiving fractionated radiotherapy.Methods From 2015 to 2016,28 patients with head and neck cancer were enrolled in this study with Shandong Cancer Hospital,consisting of 19 patients with nasopharyngeal carcinoma, 4 patients with laryngocarcinoma, and 5 patients with carcinoma of the maxillary sinus.All of them received conventionally fractionated radiotherapy.Each patient had six weekly cone-beam CT (CBCT) scans, which were performed on the first day of every week, to obtain reference images.A virtual CT image was generated by registration of planning CT and each weekly CBCT image.The four re-planning strategies were used for the reconstruction of re-planned dose, while the initial planning was used as a reference.The weekly doses calculated using virtual CT were summed together to obtain the actual dose.The actual and initial planned doses were evaluated.The nonparametric Friedman test was used to evaluate the differences between multiple groups, and the differences between any two groups were analyzed by paired t test.Results The sizes of planning target volume, clinical target volume, and left/right parotid glands (PGs) changed significantly within the six weeks (P=0.041, 0.046, 0.024, and 0.017, respectively).For these four re-planning strategies, there were significant differences between the actual dose and the initial planned dose to the PGs (all P<0.05), with average values decreased by 5.02%, 11.17%, 12.08%, and 13.19%, respectively, compared with that in the reference strategy.Conclusions Re-planning during treatment course could ensure the sparing of OARs and allow for sufficient dose to the target volume.The higher the number of re-planning strategies, the more the actual dose is close to the initial planed dose;the efficiency of two re-planning strategies is the highest.
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We present a case of unresectable cancer of the base of tongue treated with hypofractionated 3D conformal radiotherapy and concomitant chemotherapy. Based on the excellent tumour response in this radiotherapy regimen and international experience in short course treatments we shortly reviewed, we propose that this therapeutic approach could be considered in a curative setting for patients unsuitable for the a standard long course radiochemotherapy schedule.
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Humans , Appointments and Schedules , Chemoradiotherapy , Drug Therapy , Radiotherapy , Radiotherapy, Conformal , TongueABSTRACT
Objective To prospectively assess the influence of intensity-modulated radiotherapy (IMRT) and conventional radiotherapy on quality of life (QOL) in patients with head and neck cancer (HNC) for clinical guidance. Methods From May 2007 to May 2008, 102 HNC patients were enrolled in this study. Fifty-two patients were treated with IMRT and 50 with conventional radiotherapy. In patients with IMRT, at least one parotid gland was spared, and the contralateral submandibular gland was spared in 24 patients. The parotid and submandibular gland were not spared in patient with conventional radiotherapy.QOL was assessed using EORTC QLQ C30 and HN35 questionnaires at 4 time points (before radiotherapy,end of radiotherapy, 2 months and 6 months after radiotherapy). A change of 10% in scores of the instru-ment range had been previously demonstrated to be clinically significant. Results In the study, 94% (31/33) of the QOL domains were worse after IMRT or conventional radiotherapy, including 49% (16/33) with significant difference (U=2.72-5.98, all values of P<0.01) and 33% (11/33) with clinical signifi-cance. At 2 months after radiotherapy, 12% (4/33) of the domains showed clinically significant improve-ment, however, 15% (5/33) of the domains did not show any improvement (U=3.10-5.93,all value of P < 0.01). Continuous improvement in most domains of QOL was shown at 6 months after radiotherapy. Clini-cally and statistically significant improvement were shown in 21% (7/33) of the domains, and some were even better than pretreatment except in dry mouth and sticky saliva scales (U=4.49 , P<0.01 and U=4.87 ,P <0.01). Compared with conventional radiotherapy, the dry mouth and sticky saliva caused by IM-RT were milder (U=4.57,P <0.01 and U=5.57, P < 0.01) and continuous improvement were shown over time after radiotherapy (U=7.23, P <0.01 and U = 7.57, P < 0.01). Similar improvement weren't shown in patients with conventional radiotherapy. Conclusions QOL in HNC patients is significant worse after ra-diotherapy. QOL can be improved continuously over time after treatment except dry mouth and sticky saliva which are the main factors affecting QOL. IMBT, causing less dry mouth and sticky saliva when compared with conventional radiotherapy, has benefits for the preservation of QOL.
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Objective To evaluate the apparent diffusion coefficient (ADC) of parenehyma and necrosis in distinguishing among metastatic lymph nodes, lymphoma and tuberculous lymph nodes. Methods Thirty-six patients with cervical lymph nodes metastasis from the head and neck squamous cell carcinomas,19 patients with lymphoma and 23 patients with lymph nodes tuberculosis underwent diffusion-weighted imaging. The ADC values were measured and compared in parenchyma and necrosis of 177 lymph nodes confirmed by histopathology (n = 114) and clinical follow-up (n = 63). The means between two groups were compared by t-test, and one-way analysis of variance (one-way ANOVA) was used to analyze the data among three or more groups. Results The mean ADC values of parenchyma in metastatic nodes, lymphoma and tuberculous nodes were (0.93±0.16) × 10-3mm2/s, (0.64±0.13) × 10-3mm2/s and (1.01±0.11) ×10 -3 mm2/s respectively (F = 82.928, P < 0.01) ; the ADC values of necrosis in metastatic and tuberculous nodes were (2.02 ± 0. 36) × 10-3 mm2/s and (1.25 ± 0.15) × 10-3 mm2/s respectively (t = 12.045, P <0.01). An ADC value of parenchyma lower than or equal to 0.77 × 10 -3mm2/s was used as the threshold for lymphoma, with a sensitivity 83% and specificity of 89%. An ADC value of necrotic area greater than or equal to 1.60 × 103mm2/s was used as the threshold for metastatic nodes, with a sensitivity of 88% and specificity of 100%. Conclusion The ADC value of lymph nodes, especially for their internal necrotic areas, can help judge the nature of the cervical lymph nodes.
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Objective To improve the external irradiation technique for Head-neck neoplasms.Methods 95 patients with Head-neck neoplasms confirmed by pathology,were fixed with head pillow mask , isocenter irradiation,technique utilizing cerrobend block.Radical therapy dose was 72 (70～80)Gy/35～40 fractions in 7～8 weeks for general carcinoma and 50～55Gy/28～31 fractions in 5 6～6 2 weeks for NHL .Preventive dose was 56 (50～60)Gy/25～30 fractions in 5～6 weeks for general carcinoma and 45～50Gy/25～28 fractions in 5～5 6 weeks for NHL.A short and a long-term clinical outcome, acute and late radiation reactions were observed.Results After 1～2 months following radiation therapy,CT scans revealed that the primary lesion complete remission rate was 58 57% , and obvious remission rate was 32 86%.The normal mucous membrane acute radiation reaction rates were G0 56 84% , GⅠ 42 10% , GⅡ 1 05%,respectively.After 1～2 years following radiation therapy,the spinal cord and brain stem radiation injury rate was zoro.Conclusions The improving external irradiation technique may elevate local control rate better,and reduce radiation reactions of patients with head-neck neoplasms.