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Clinical and dosimetric characteristics compared to respects of constraints in intensity-modulated radiotherapy for head and neck cancers
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Posters The treatment plan was an IMRT with integrated boost over 2 PTVs, (PTVl to 54Gy and PTV2 to 70Gy) with constraints on spinal chord, parothyd glands and cochlea. After three weeks of treatment, a new CT was taken in order to evaluate the tumor response. The CT images showed a significant reduction on both PTVsand the parothyd glands. Also, an evident external contour modification was noted. The calculated set of fluence maps was superimposed on the new CT and a new set of DVH was analyzed. R e s u l t s : We had seen a large volume variation on PTVs and some OAR. PTVl was showed a 47% reduction, PTV2 a reduction of 64% and parothyds gland a mean reduction of 36%. The analysis of the new calculated DVH showed more hot spots than the accepted plan. This change was more significant on OAR than on PTV. The maximum dose for PTVl increased from 70 Gy to 71 Gy and PTV2 from 84Gy to 88 Gy. For the OAR, the spinal chord increased from 47.9 Gy to $4.9 Gy. Also the skin surface showed large hot spots, increasing the dose from 44.3Gy to 89.1 Gy. Conclusions: As the results show, in IMRT treatment on head and neck regions with large tumors, it is very important to do a follow up of patient morphology during the initial weeks of treatment, when CT images need to be evaluated to quantify the tumor response. If a significant morphological change is observed (according to the criteria of physician and physicist), we recommend that the DVH of the treatment plan is recalculated, superimposing the initial set of fluence map on the new set of CT images. If these new DVH obtained are not in good agreement with the acceptance criteria, a new set of fluence maps should be calculated with the new CT images. 141 poster CHEMORADIATION FOR ADVANCED HEAD AND NECK CARCINOMA USING CONCURRENTWEEKLY CISPLATIN CHEMOTHERAPY A. Winship, C. Thomas, M. O'ConnelI, F. Caiman GuY's ANDSTTHOMAS'NHS FOUNDATIONTRUST,Clinical Oncology, London,
United Kingdom Purpose/Objective: To evaluate the outcome of patients receiving chemoradiation with concurrent weekly cisplatin chemotherapy for advan~:ed head and neck carcinoma. Materials/Methods: Patients with histologically proven squamous cell carcinoma of the head and neck treated with radical radiotherapy and concurrent weekly cisplatin chemotherapy at a dose of 40mg/m 2 at Guy's and St Thomas' NHS Foundation Trust between July 2000 and January 2005 were identified. Patient characteristics, details of radiotherapy and chemotherapy along with toxicity, recurrence and survival data were recorded. Results: 25 patients, 22 male and 3 female, median age 61 years, age range 44-78 years, were identified. Mean follow-up was 35 months, range 5-75 months. 14 of the 25 patients (56%) were diagnosed with oropharyngeal carcinoma, 5 (20%) with laryngeal carcinoma, 5 (20%) with hypopharyngeal carcinoma and 1 (4%) with carcinoma of the oral cavity. 17 patients (68%) were stage III and 8 (32%) were stage IV. 20 of the 25 patients (80%) received chemoradiation alone, 1 patient (4%) received chemoradiation post-operatively and 4 patients (16%) underwent neck dissection post-treatment. 23 of the 25 patients (92%) received a radiation dose of at least 64Gy in 30 daily fractions. Mean overall treatment time was 43 days, range 40-46 days. 2 patients (8%) received 54-SSGy in 20 daily fractions over 26 and 29 days. 17 patients (68%) completed the prescribed radiotherapy without a break. All patients received weekly cisplatin chemotherapy (40mg/m2), mean number of cycles 3.8, median number 4, range 1-5 cycles. 18 patients (72%) completed the planned number of cycles. 8 patients (32%) required blood transfusion to maintain their haemoglobin levels above 12g/dl. No patient developed significant or symptomatic neutropenia or thrombocytopenia. Mean weight loss was 6kg, range 1-20kg. 18 patients (72%) required enteral feeding. 8 patients (32%) required hospital admission. 22 of the 25 patients (88%) achieved a complete response following chem-
oradiation. 12 patients (48%) were alive and disease-free, 3 (12%) were alive with recurrent disease and 7 patients (28%) had died, 4 of disease and 3 of other causes. 3 patients (12%) were lost to followup. 2 patients (8%) developed second malignancies. Conclusions: Chemoradiation using concurrent weekly cisplatin chemotherapy at a dose of 40mg/m 2 is an active, well-tolerated outpatient regimen with favourable rates of local control and survival. Clinical trials comparing weekly and three-weekly cisplatin are awaited. 142 poster CLINICAL AND DOSIMETRIC CHARACTERISTICS COMPARED TO RESPECTS OF CONSTRAINTS IN INTENSITY-MODULATED RADIOTHERAPY FOR HEAD AND NECK CANCERS E. Martin 1, M. Bosset~, C. Deville2,G. Trucl,J. Brenier ~, R Maingon ~ ICENTREGF LECLERC,Radiotherapy, Dijon, France, 2CENTREGF LECLERC,Biostatistics, Dijon, France Purpose/Objective: To define clinical and dosimetric characteristics for respects of constraints in head and neck cancer patients treated with intensity-modulated radiotherapy (IMRT). Materials/Methods: Between August 2001 and July 2005, 75 patients with non metastatic head and neck cancer were treated with IMRT for curative intent. There were 57 men and 18 women with a median age of 60 years (range 29-83 years). Of the remaining 75 patients, 45 were treated with definitive IMRT and 19 received postoperative IMRT. Neck nodes irradiation were bilateral for 46 patients and only unilateral for 29 patients. Sites included were oropharynx, 18 ; nasal cavity/paranasal sinus, 15 ; hypopharynx, 12 ; oral cavity, 11, nasopharynx, 9 ; unknown primary, 6 ; thyroid, 3 and larynx, 1. Three clinical target volumes (CTV1, CTV2 and CTV3) were defined. For definitive IMRT, the prescribed doses to CTV1, CTV2 and CTV3 were 70-72 Gy, 60 Gy and 50-54 Gy respectively. For the post-operative cohort, the prescribed doses to CTV1, CTV2 and CTV3 were 6670 Gy, 60 Gy and 50-54 Gy respectively. Dose constraints for organs at risk were Dmean _<26 Gy for parotid and submandibulary glands, Dmax < 60 Gy for optic nerves, Dmax _<15 Gy for anterior part of the eyes and Dmax < 45 gyfor spinal cord. Results: For both irradiation, the mean dose to the PTV was not significantly different to the prescribed dose (p=0.38). Eighty-six percent of the PTV received more than 95 % and less than 107 % of prescribed dose. For bilateral irradiation, the mean dose to the contralateral and ipsilateral parotid glands were 28.1 Gy and 26.3 Gy (p=0.8 and p=0.1 respectively). Dose constraints to the submandibulary glands were not respected either in unilateral nor bilateral neck irradiation. For unilateral irradiation, the mean dose to the contralateral parotid gland was significantly inferior to the constraint dose (p<0.0001). For irradiation of paranasal sinus carcinomas, the maximal dose to the controlateral and ipsilateral optic nerves remained significantly lower than the constraint doses (p~0.01) after uni or bilateral irradiation. Dose constraints to the anterior part of the eyes were not respected in uni or bilateral irradiation. With a median follow-up of 18 months (range 1 to 50 months), there were 1S Iocoregional recurrences and 18 deaths. Univariate and multivariate analysis evaluating prognosis factors link to dose constraints are under progress and will be reported during the meeting. Conclusions: The coverage of target volumes are obtain with our treatment planning system. The respect of the penalties introduced in the system are different when one or both sites of the neck have been irradiated. Differences are observed for respect of the constraints applied to the parotid or to the submandibulary glands. Strict dose constraints to the anterior part of the eyes during irradiation of paranasal sinuses are not reached.
Posters The treatment plan was an IMRT with integrated boost over 2 PTVs, (PTVl to 54Gy and PTV2 to 70Gy) with constraints on spinal chord, parothyd glands and cochlea. After three weeks of treatment, a new CT was taken in order to evaluate the tumor response. The CT images showed a significant reduction on both PTVsand the parothyd glands. Also, an evident external contour modification was noted. The calculated set of fluence maps was superimposed on the new CT and a new set of DVH was analyzed. R e s u l t s : We had seen a large volume variation on PTVs and some OAR. PTVl was showed a 47% reduction, PTV2 a reduction of 64% and parothyds gland a mean reduction of 36%. The analysis of the new calculated DVH showed more hot spots than the accepted plan. This change was more significant on OAR than on PTV. The maximum dose for PTVl increased from 70 Gy to 71 Gy and PTV2 from 84Gy to 88 Gy. For the OAR, the spinal chord increased from 47.9 Gy to $4.9 Gy. Also the skin surface showed large hot spots, increasing the dose from 44.3Gy to 89.1 Gy. Conclusions: As the results show, in IMRT treatment on head and neck regions with large tumors, it is very important to do a follow up of patient morphology during the initial weeks of treatment, when CT images need to be evaluated to quantify the tumor response. If a significant morphological change is observed (according to the criteria of physician and physicist), we recommend that the DVH of the treatment plan is recalculated, superimposing the initial set of fluence map on the new set of CT images. If these new DVH obtained are not in good agreement with the acceptance criteria, a new set of fluence maps should be calculated with the new CT images. 141 poster CHEMORADIATION FOR ADVANCED HEAD AND NECK CARCINOMA USING CONCURRENTWEEKLY CISPLATIN CHEMOTHERAPY A. Winship, C. Thomas, M. O'ConnelI, F. Caiman GuY's ANDSTTHOMAS'NHS FOUNDATIONTRUST,Clinical Oncology, London,
United Kingdom Purpose/Objective: To evaluate the outcome of patients receiving chemoradiation with concurrent weekly cisplatin chemotherapy for advan~:ed head and neck carcinoma. Materials/Methods: Patients with histologically proven squamous cell carcinoma of the head and neck treated with radical radiotherapy and concurrent weekly cisplatin chemotherapy at a dose of 40mg/m 2 at Guy's and St Thomas' NHS Foundation Trust between July 2000 and January 2005 were identified. Patient characteristics, details of radiotherapy and chemotherapy along with toxicity, recurrence and survival data were recorded. Results: 25 patients, 22 male and 3 female, median age 61 years, age range 44-78 years, were identified. Mean follow-up was 35 months, range 5-75 months. 14 of the 25 patients (56%) were diagnosed with oropharyngeal carcinoma, 5 (20%) with laryngeal carcinoma, 5 (20%) with hypopharyngeal carcinoma and 1 (4%) with carcinoma of the oral cavity. 17 patients (68%) were stage III and 8 (32%) were stage IV. 20 of the 25 patients (80%) received chemoradiation alone, 1 patient (4%) received chemoradiation post-operatively and 4 patients (16%) underwent neck dissection post-treatment. 23 of the 25 patients (92%) received a radiation dose of at least 64Gy in 30 daily fractions. Mean overall treatment time was 43 days, range 40-46 days. 2 patients (8%) received 54-SSGy in 20 daily fractions over 26 and 29 days. 17 patients (68%) completed the prescribed radiotherapy without a break. All patients received weekly cisplatin chemotherapy (40mg/m2), mean number of cycles 3.8, median number 4, range 1-5 cycles. 18 patients (72%) completed the planned number of cycles. 8 patients (32%) required blood transfusion to maintain their haemoglobin levels above 12g/dl. No patient developed significant or symptomatic neutropenia or thrombocytopenia. Mean weight loss was 6kg, range 1-20kg. 18 patients (72%) required enteral feeding. 8 patients (32%) required hospital admission. 22 of the 25 patients (88%) achieved a complete response following chem-
oradiation. 12 patients (48%) were alive and disease-free, 3 (12%) were alive with recurrent disease and 7 patients (28%) had died, 4 of disease and 3 of other causes. 3 patients (12%) were lost to followup. 2 patients (8%) developed second malignancies. Conclusions: Chemoradiation using concurrent weekly cisplatin chemotherapy at a dose of 40mg/m 2 is an active, well-tolerated outpatient regimen with favourable rates of local control and survival. Clinical trials comparing weekly and three-weekly cisplatin are awaited. 142 poster CLINICAL AND DOSIMETRIC CHARACTERISTICS COMPARED TO RESPECTS OF CONSTRAINTS IN INTENSITY-MODULATED RADIOTHERAPY FOR HEAD AND NECK CANCERS E. Martin 1, M. Bosset~, C. Deville2,G. Trucl,J. Brenier ~, R Maingon ~ ICENTREGF LECLERC,Radiotherapy, Dijon, France, 2CENTREGF LECLERC,Biostatistics, Dijon, France Purpose/Objective: To define clinical and dosimetric characteristics for respects of constraints in head and neck cancer patients treated with intensity-modulated radiotherapy (IMRT). Materials/Methods: Between August 2001 and July 2005, 75 patients with non metastatic head and neck cancer were treated with IMRT for curative intent. There were 57 men and 18 women with a median age of 60 years (range 29-83 years). Of the remaining 75 patients, 45 were treated with definitive IMRT and 19 received postoperative IMRT. Neck nodes irradiation were bilateral for 46 patients and only unilateral for 29 patients. Sites included were oropharynx, 18 ; nasal cavity/paranasal sinus, 15 ; hypopharynx, 12 ; oral cavity, 11, nasopharynx, 9 ; unknown primary, 6 ; thyroid, 3 and larynx, 1. Three clinical target volumes (CTV1, CTV2 and CTV3) were defined. For definitive IMRT, the prescribed doses to CTV1, CTV2 and CTV3 were 70-72 Gy, 60 Gy and 50-54 Gy respectively. For the post-operative cohort, the prescribed doses to CTV1, CTV2 and CTV3 were 6670 Gy, 60 Gy and 50-54 Gy respectively. Dose constraints for organs at risk were Dmean _<26 Gy for parotid and submandibulary glands, Dmax < 60 Gy for optic nerves, Dmax _<15 Gy for anterior part of the eyes and Dmax < 45 gyfor spinal cord. Results: For both irradiation, the mean dose to the PTV was not significantly different to the prescribed dose (p=0.38). Eighty-six percent of the PTV received more than 95 % and less than 107 % of prescribed dose. For bilateral irradiation, the mean dose to the contralateral and ipsilateral parotid glands were 28.1 Gy and 26.3 Gy (p=0.8 and p=0.1 respectively). Dose constraints to the submandibulary glands were not respected either in unilateral nor bilateral neck irradiation. For unilateral irradiation, the mean dose to the contralateral parotid gland was significantly inferior to the constraint dose (p<0.0001). For irradiation of paranasal sinus carcinomas, the maximal dose to the controlateral and ipsilateral optic nerves remained significantly lower than the constraint doses (p~0.01) after uni or bilateral irradiation. Dose constraints to the anterior part of the eyes were not respected in uni or bilateral irradiation. With a median follow-up of 18 months (range 1 to 50 months), there were 1S Iocoregional recurrences and 18 deaths. Univariate and multivariate analysis evaluating prognosis factors link to dose constraints are under progress and will be reported during the meeting. Conclusions: The coverage of target volumes are obtain with our treatment planning system. The respect of the penalties introduced in the system are different when one or both sites of the neck have been irradiated. Differences are observed for respect of the constraints applied to the parotid or to the submandibulary glands. Strict dose constraints to the anterior part of the eyes during irradiation of paranasal sinuses are not reached.