Abstract | PURPOSE: PATIENTS AND METHODS: At the Alexis Vautrin Cancer Center, 23 patients have been treated with IMRT for HNC since January 2002-August 2003. The first 10 patients with a minimum follow-up of 3 months were analyzed. All tumors were oropharyngeal. There were four females and six males, with a mean age of 50 years (range 39-66). Stages were I-II in eight and III-IV in two. CTV1 was microscopic disease and N0 neck (prescribed dose : 50 Gy) and CTV2 was macroscopic disease and the volume at risk (prescribed dose: 66-70 Gy). PTV were CTV + 5 mm. Patient's immobilization consisted of a five-point head neck shoulder thermoplastic mask. Set-up verifications were done by semi-automatically matching portal images and digitized reconstructed radiographs. IMRT used dynamic multileaf collimation. Five patients (group A) received 50 Gy IMRT (two post-operative and three with a brachytherapy boost with a mean dose: 27.5 Gy), and five patients (group B) received 66-70 Gy IMRT (four post-operative). Acute and late normal tissue effects were graded according to the RTOG-EORTC radiation morbidity scoring criteria. RESULTS: With a median follow-up of 7.4 months (range 3-18.5), no patient died or had loco-regional relapse. The displacements were <4 mm in 98% cases. CTV1 and 2 received 95% of the prescribed dose in 100% of the volume. On average the mean dose to the contralateral parotid was 25.5 Gy for group A vs. 31 Gy for group B (P = 0.09). Mean doses <26 Gy were obtained in three of five patients in group A vs. zero of five patients in group B (P = 0.04). Acute skin toxicities were grade 1 in five patients, grade 2 in four and grade 3 in one. Acute mucositis cases were grade 1 in three patients, grade 2 in five and localized grade 3 in two. At 3 months, 50% of the patients had a grade 0-1 late xerostomia. CONCLUSION: The 26 Gy dose limit constraint to the contralateral parotid was easier to satisfy when IMRT was prescribed at a maximum dose of 50 Gy. Acute toxicity is low. The displacements in the mask indicate that it is possible to define the PTV as CTV + 4 mm. This reduction should decrease the mean dose to the parotids. At 3 months, a 50% rate of grade 0-1 late xerostomia encourages the hope of a very low rate at 2 years.
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Authors | M Lapeyre, V Marchesi, A Mege, P Aletti, P Graff, S Racadot, A Noel, C Marchal |
Journal | Cancer radiotherapie : journal de la Societe francaise de radiotherapie oncologique
(Cancer Radiother)
Vol. 8
Issue 3
Pg. 134-47
(Jun 2004)
ISSN: 1278-3218 [Print] France |
Vernacular Title | Radiothérapie conformationnelle avec modulation d'intensité des cancers des voies aérodigestives supérieures avec irradiation bilatérale du cou: résultats préliminaires. |
PMID | 15217581
(Publication Type: Clinical Trial, Controlled Clinical Trial, Journal Article)
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Topics |
- Adult
- Aged
- Carcinoma, Squamous Cell
(pathology, radiotherapy)
- Dose Fractionation, Radiation
- Dose-Response Relationship, Radiation
- Female
- Head and Neck Neoplasms
(pathology, radiotherapy)
- Humans
- Male
- Middle Aged
- Neoplasm Recurrence, Local
- Radiation Injuries
- Treatment Outcome
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