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Objective:To investigate the feasibility of individualized primary clinical target volume (CTV) delineation in intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC).Methods:Clinical data of 87 consecutive patients newly diagnosed with lateralized NPC in Jiangsu Cancer Hospital between October 2016 and February 2018 were retrospectively analyzed. Lateralized NPC is defined as tumor invasion not exceeding the contralateral wall. According to the tumor spread, the primary CTV was optimized as follows: CTV2 only covered the medial part of the contralateral pterygopalatine fossa, whereas the contralateral foramen oval was not included; on the level of parapharyngeal space, the contralateral side of CTV only covered the posterior lateral lymph nodes, whereas the contralateral internal jugular vein was not regularly covered. Failure patterns and 5-year survival [local control rate (LCR), progression-free survival (PFS) and overall survival (OS)] were evaluated by Kaplan-Meier method. Paired t-test and rank-sum test were used to analyze the dose variation in the optimized region and adverse reactions. Results:The median follow-up time was 59.5 months. The 5-year LCR, PFS, and OS were 98.9%, 86.5% and 92.1%, respectively. There was no local recurrence in the optimized area of CTV. Dosimetric comparison results showed that the doses of parotid gland, temporal lobe, cochlea and middle ear on the contralateral side were reduced by 13.45%, 9.14%, 38.83%, and 29.36%, respectively. Four cases (4.6%) developed grade 3 hearing loss, all on the ipsilateral side. The optimized scheme significantly alleviated the hearing loss on the contralateral side compared to that on the ipsilateral side ( P<0.001). Other grade 3 late adverse reactions included cranial nerve injury, subcutaneous fibrosis in the neck and visual impairment, with 1 case each. Conclusion:Individualized primary CTV for lateralized NPC is feasible and safe, with obvious dosimetric advantages and reduced adverse reaction rate, which is worthy of clinical promotion.
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Objective To explore the upper bound of Ⅱb region in the clinical target volume ( CTV ) for intensity?modulated radiotherapy ( IMRT ) for nasopharyngeal carcinoma ( NPC ) , and to establish a standard for personalized reduction in the range ofⅡb region. Methods A retrospective analysis was performed on the IMRT results of 142 patients newly diagnosed with NPC who were admitted to our hospital from 2012 to 2014. According to the American Joint Committee on Cancer 2010 staging system, there were 8 patients with stageⅠ disease, 37 stage Ⅱ, 41 stage Ⅲ, and 56 stage Ⅳ. The distribution pattern of cervical lymph nodes in NPC was studied based on the imaging results. Comparison of the dose to parotid glands between patients with and without reduction in the range ofⅡb region was made by t test and t'test. Results The metastasis rates of the most common diseased lymph nodes, lateral retropharyngeal lymph node and Ⅱb lymph node, were 75?4% and 67?6%, respectively. In the patients with metastases inⅡb region, 51?0% had high?risk positive lymph nodes and 6?3% had positive lymph nodes beyond the upper bound of Ⅱb region defined by the Radiation Therapy Oncology Group system. It was safe to narrow down Ⅱb region in patients who met the formulated standard. The D50 and V26 values for parotid glands were significantly reduced after optimization of CTV ( P=0?000) . Conclusions The upper bound ofⅡb region, in principle, should reach the lateral skull base during the delineation of the cervical CTV for NPC. In order to protect the parotid glands, however, personalized reduction in the upper bound of Ⅱb region is recommended for patients who meet the formulated standard.
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Objective To assess the efficacy and safety of nimotuzumab in combination with radiochemotherapy in locoregionally advanced nasopharyngeal carcinoma (NPC).Methods 42 patients with locoregionally advanced NPC were retrospectively analyzed.They all received the treatment of nimotuzumab in combination with radiochemotherapy.Intensity modulated radiationtherapy (IMRT) was applied and the prescribed radiation dose administered to the primary tumor was between 70 to 79.2 Gy in 32-37 fractions and 41-49 days.The dose administered to lymph nodes was between 65 to 76 Gy in 32-37 fractions and 41-49 days.Nimotuzumab was given weekly during irradiation.All patients received chemotherapy.Results The main adverse events were mucositis,bone marrow suppression,dermatitis and xerostomia.Grade 1 or 2 oropharyngeal mucositis occurred in 29 (69.0 ％) patients,and grade 3 in 2 (4.8 ％).Grade 1 or 2,3 or 4 leucopemia occurred in 25 cases (59.5 ％),16 cases (38.1％),respectively,without occurrence of febrile neutropenia.There was no treatment related death.Complete response (CR) rate was 90.5 ％ (38/42),partial response (PR) rate was 9.5 ％ (4/42) and the total efficiency was 100 ％.After a median follow-up of 22.5 months,the 1-year local control rate was 100 ％.1-year distant metastasis-free survival rate was 92.7 ％.1-year overall survival rate was 95.2 ％.Conclusion Nimotuzumab combined with radiochemotherapy was efficient and safe for locoregionally advanced NPC.
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Objective To investigate the effect of lobaplatin combined with irradiation on human nasopharyngeal cancer cell line CNE2,and to illuminate its mechanism of radiosensitization.Methods MTT assay was used to detect the outcome of lobaplatin and irradiation on CNE2 cell proliferation.Clonogenic assay was applied to testify the radiosensitization effect of lobaplatin on the cells.Flow cytometry was used to check the cell cycle distribution and cell apoptosis.Western was used to detect the expression of Bcl-2,Bax and cleaved Caspase-3.Results The proliferation of CNE2 cells was reduced by lobaplatin in a dose-dependent manner.50IC of lobaplatin on CNE2 cells and lobaplatin combined with 4 Gy irradiation was 1.610 μmol/L and 0.077 μmol/L,respectively.The radiosensitization ratio of the combination group was over 3.Within 24 h of drug treatment,the percent of cells in G2/M phase increased with the concentration of lobaplatin.When the concentration of lobaplatin increased to 6 μmol/L,the cells of combination group were arrested at S phase.The apoptosis rate of lobaplatin (5 μmol/L) group,radiotherapy(4 Gy)group and combination group was 15.6％,11.3％ and 61.8％,respectively.Western blot showed that the expressions of Bax and cleaved Caspase-3 increased but Bcl-2 decreased in the combination group.Conclusion Lobaplatin could increase radiosensitization of human nasopharyngeal cancer cell line CNE2,probably by depressing Bcl-2 but enhancing Bax expression and hence activating Bcl-2/Bax-Caspase signaling pathway.
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Objective To investigate the survival data and acute toxicities in patients with locoregionally advanced nasopharyngeal carcinoma who receive intensity-modulated radiotherapy (IMRT)with concurrent chemotherapy using nedaplatin plus 5-fluorouracil (PF) or taxol plus nedaplatin (TP).Methods A retrospective analysis was performed on the clinical data of 152 patients with stage Ⅲ or Ⅳa nasopharyngeal carcinoma who were admitted to our hospital in 2009-2010.Of the 152 patients,80 received IMRT with concurrent PF chemotherapy,and 72 received IMRT with concurrent TP chemotherapy;there were at least 2 cycles of concurrent chemotherapy in both groups.The Kaplan-Meier method was used to calculate the survival rates,and the log-rank test was used to analyze the survival difference ; the chisquare test was used to compare the acute toxicities in the two groups.Results The follow-up rate was 100％.The 2-year relapse-free survival rate,distant metastasis-free survival rate,progression-free survival rate,and disease-specific death rate for the IMRT/PF group were 95％,82％,81％,and 13％,respectively,versus 97％,83％,79％,and 12％ for the IMRT/TP group (x2 =0.03,0.02,0.62,and 0.22,P=0.861,0.881,0.431,and 0.638).The incidence rates of leukopenia (grade ≥3),neutropenia (grade ≥ 3),thrombocytopenia (grade ≥ 3),ALT elevation (grade ≥ 2),and oral mucositis (grade ≥3) for the IMRT/PF group were 33％,23％,14％,8％,and 12％,respectively,versus 60％,47％,28％,18％,and 25％ for the IMRT/TP group (x2 =11.33,10.29,4.59,3.94,and 3.94,P =0.001,0.001,0.032,0.047,and 0.047).Conclusions Compared with IMRT with concurrent PF chemotherapy,IMRT with concurrent TP chemotherapy does not lead to significantly better survival and results in more acute toxicities in the patients with locoregionally advanced nasopharyngeal carcinoma.