doi:10.1016/j.ijrobp.2006.12.065 CLINICAL INVESTIGATION Head and Neck IS PLANNED NECK DISSECTION NECESSARY FOR HEAD AND NECK CANCER AFTER INTENSITY-MODULATED RADIOTHERAPY? MIN YAO, M.D., PH.D.,* † HENRY T. HOFFMAN, M.D.,* † KRISTI CHANG, M.D., † GERRY F. FUNK, M.D.,* † RUSSELL B. SMITH, M.D.,* † HUAMING TAN, M.S., § GERALD H. CLAMON, M.D., ‡ KEN DORNFELD, M.D., PH.D.,* † AND JOHN M. BUATTI, M.D.* † *Departments of Radiation Oncology, † Otolaryngology, and ‡ Medical Oncology, Holden Comprehensive Cancer Center, University of Iowa Health Care, Iowa City, IA; and § Department of Biostatistics, College of Public Health, The University of Iowa, Iowa City, IA Purpose: The objective of this study was to determine regional control of local regional advanced head and neck squamous cell carcinoma (HNSCC) treated with intensity-modulated radiotherapy (IMRT), along with the role and selection criteria for neck dissection after IMRT. Methods and Materials: A total of 90 patients with stage N2A or greater HNSCC were treated with definitive IMRT from December 1999 to July 2005. Three clinical target volumes were defined and were treated to 70 to 74 Gy, 60 Gy, and 54 Gy, respectively. Neck dissection was performed for selected patients after IMRT. Selection criteria evolved during this period with emphasis on post-IMRT [ 18 F] fluorodeoxyglucose positron emission tomography in recent years. Results: Median follow-up for all patients was 29 months (range, 0.2–74 months). All living patients were followed at least 9 months after completing treatment. Thirteen patients underwent neck dissection after IMRT because of residual lymphadenopathy. Of these, 6 contained residual viable tumor. Three patients with persistent adenopathy did not undergo neck dissection: 2 refused and 1 had lung metastasis. Among the remaining 74 patients who were observed without neck dissection, there was only 1 case of regional failure. Among all 90 patients in this study, the 3-year local and regional control was 96.3% and 95.4%, respectively. Conclusions: Appropriately delivered IMRT has excellent dose coverage for cervical lymph nodes. A high radiation dose can be safely delivered to the abnormal lymph nodes. There is a high complete response rate. Routine planned neck dissection for patients with N2A and higher stage after IMRT is not necessary. Post-IMRT [ 18 F] fluorodeoxyglucose positron emission tomography is a useful tool in selecting patients appropriate for neck dissection. © 2007 Elsevier Inc. Head-and-neck cancer, IMRT, Planned neck dissection. INTRODUCTION Many locoregionally advanced head and neck squamous cell carcinoma (HNSCC) patients are now treated with radiation, with or without concurrent chemotherapy, to achieve organ preservation. The management of nodal dis- ease postradiation is controversial. It is generally agreed patients with N1 disease with complete response postradia- tion do not require neck dissection. However patients with N2 or N3 disease have routine, planned neck dissections in many institutions, regardless of treatment response. Planned neck dissection has been incorporated into organ preserva- tion protocols in clinical trials. This strategy evolved in the early 1970s because the rate of ipsilateral neck recurrence was lower in those treated with combined radiation and surgery compared with those treated with either modality alone (1, 2). With the advance in radiation techniques and the addition of concurrent chemotherapy, however, a high proportion of patients achieve complete response. Many patients who have neck dissection following (chemo)radia- tion often have no residual viable cancer in the resected lymph nodes. The risk of isolated neck recurrence in pa- tients with complete response has also been reported to be low, even without neck dissection (3–9). These findings support the practice of determining the need for neck dis- section based on postradiation findings rather than preradia- tion staging. Controversy continues because of reports of high regional recurrence rates for those patients who do not Reprint requests to: Min Yao, M.D., Ph.D., Department of Radiation Oncology, 01625 WPFP, 200 Hawkins Drive, Iowa City, IA 52242; Tel: (319) 356-7603; Fax: (319) 356-1530; E- mail: min-yao@uiowa.edu Presented in part at the Annual Meeting of American Head and Neck Society, Chicago, IL, August 19, 2006. Acknowledgments—The authors thank Kellie Bodeker for editorial assistance and manuscript preparation. Conflict of interest: none. Received Nov 28, 2006, and in revised form Dec 28, 2006. Accepted for publication Dec 28, 2006. Int. J. Radiation Oncology Biol. Phys., Vol. 68, No. 3, pp. 707–713, 2007 Copyright © 2007 Elsevier Inc. Printed in the USA. All rights reserved 0360-3016/07/$–see front matter 707