Background Helical tomotherapy （HT） is a new image-guided intensity-modulated radiation therapy （IMRT）.The aim of this study was to evaluate the changes in the target volume and organs at risk （OARs） of patients...Background Helical tomotherapy （HT） is a new image-guided intensity-modulated radiation therapy （IMRT）.The aim of this study was to evaluate the changes in the target volume and organs at risk （OARs） of patients with nasopharyngeal carcinoma （NPC） during helical tomotherapy.Methods Forty-three patients with NPC and treated via HT from March 2008 to January 2010 were reviewed retrospectively.Repeated CT scanning and plan adaptation were conducted at the 20th fraction during radiotherapy.The volumetric differences between the two scans were evaluated for nasopharyngeal tumor and retro- pharyngeal lymph nodes （GTVnx）,neck lymph nodes （GTVnd）,and parotid glands,as well as the axial diameter of the head.Results The median interval between the two scans was 25 days （23-28 days）.The volumetric decrease in GTVnx was 30.1% （median,29.8%） and in GTVnd 41.6% （median,45.9%）.The variation in the GTVnd volume was correlated with the weight loss of the patient.The volume of the left parotid gland decreased by 35.5% （median,33.4%） and of the right parotid glands decreased by 36.8% （median,33.5%）.The axial diameter of the head decreased by 9.39% （median,9.1%）.Conclusions The target volume and OARs of patients with NPC varied considerably during HT.These changes may have potential dosimetric effects on the target volume and/or OARs and influence the clinical outcome.Repeated CT scanning and replanning during the HT for NPC patients with a large target volume or an obvious weight loss are recommended.展开更多
Objective： To evaluate the short-term clinical outcomes of intracranial germinoma patients treated with craniospinal irradiation （CSI） using helical tomotherapy （HT） system in our center. Methods： Twenty-three p...Objective： To evaluate the short-term clinical outcomes of intracranial germinoma patients treated with craniospinal irradiation （CSI） using helical tomotherapy （HT） system in our center. Methods： Twenty-three patients who were treated with CSI in our center from January 2008 to July 2012 were collected, with an average age of 20. M1 of the patients＇ CSI used the HT system. The total doses were 27-36 Gy/15-20 F （1.5-2 Gy per fraction）, and total local doses were 46-60 Gy/30-50 F （5 fractions per week）. M1 female patients for CSI were treated with left-right parallel-opposed field irradiation to protect their ovarian functions. Median follow-up time was 30.9 months （range, 5-67 months）. The SPSS19.0 software was used, and the overall survival （OS） was calculated using the Kaplan-Meier method. Results： Among 17 patients with assessable tumors, 9 cases （52.9%） were CR, 7 cases （41.2%） were PR, and 1 case （5.9%） was SD. Hematological toxicity was the severest side-effect occurred in the procedure of CSI. The level 1-4 acute leukopenia were 8.7%, 30.4%, 34.8% and 21.7% and the level 1-4 acute thrombopenia were 8.7%, 30.4%, 21.7% and 8.7%, respectively. Conclusions： For primary intracranial germinomas, HT can be used to implement CSI for simplifying radiotherapy procedures, improving radiotherapy accuracy, enhancing protection of peripheral organs at risk （ORA） and guaranteeing therapeutic effects. With the acceptable acute and long-term toxicity, CSI using HT in intracranial germinoma patients can be a safe and alternative mode.展开更多
文摘Background Helical tomotherapy （HT） is a new image-guided intensity-modulated radiation therapy （IMRT）.The aim of this study was to evaluate the changes in the target volume and organs at risk （OARs） of patients with nasopharyngeal carcinoma （NPC） during helical tomotherapy.Methods Forty-three patients with NPC and treated via HT from March 2008 to January 2010 were reviewed retrospectively.Repeated CT scanning and plan adaptation were conducted at the 20th fraction during radiotherapy.The volumetric differences between the two scans were evaluated for nasopharyngeal tumor and retro- pharyngeal lymph nodes （GTVnx）,neck lymph nodes （GTVnd）,and parotid glands,as well as the axial diameter of the head.Results The median interval between the two scans was 25 days （23-28 days）.The volumetric decrease in GTVnx was 30.1% （median,29.8%） and in GTVnd 41.6% （median,45.9%）.The variation in the GTVnd volume was correlated with the weight loss of the patient.The volume of the left parotid gland decreased by 35.5% （median,33.4%） and of the right parotid glands decreased by 36.8% （median,33.5%）.The axial diameter of the head decreased by 9.39% （median,9.1%）.Conclusions The target volume and OARs of patients with NPC varied considerably during HT.These changes may have potential dosimetric effects on the target volume and/or OARs and influence the clinical outcome.Repeated CT scanning and replanning during the HT for NPC patients with a large target volume or an obvious weight loss are recommended.
文摘Objective： To evaluate the short-term clinical outcomes of intracranial germinoma patients treated with craniospinal irradiation （CSI） using helical tomotherapy （HT） system in our center. Methods： Twenty-three patients who were treated with CSI in our center from January 2008 to July 2012 were collected, with an average age of 20. M1 of the patients＇ CSI used the HT system. The total doses were 27-36 Gy/15-20 F （1.5-2 Gy per fraction）, and total local doses were 46-60 Gy/30-50 F （5 fractions per week）. M1 female patients for CSI were treated with left-right parallel-opposed field irradiation to protect their ovarian functions. Median follow-up time was 30.9 months （range, 5-67 months）. The SPSS19.0 software was used, and the overall survival （OS） was calculated using the Kaplan-Meier method. Results： Among 17 patients with assessable tumors, 9 cases （52.9%） were CR, 7 cases （41.2%） were PR, and 1 case （5.9%） was SD. Hematological toxicity was the severest side-effect occurred in the procedure of CSI. The level 1-4 acute leukopenia were 8.7%, 30.4%, 34.8% and 21.7% and the level 1-4 acute thrombopenia were 8.7%, 30.4%, 21.7% and 8.7%, respectively. Conclusions： For primary intracranial germinomas, HT can be used to implement CSI for simplifying radiotherapy procedures, improving radiotherapy accuracy, enhancing protection of peripheral organs at risk （ORA） and guaranteeing therapeutic effects. With the acceptable acute and long-term toxicity, CSI using HT in intracranial germinoma patients can be a safe and alternative mode.
