Proceedings of the 52nd Annual ASTRO Meeting S465

Materials/Methods: A total of 32 patients with hypopharyngeal, laryngeal, or oropharyngeal cancer and synchronous ormetachronous esophageal cancer between 1998 and 2008were retrospectively included in this study. The median age at primarydiagnosis was 60.2 years (range: 40.7-79.6 years). Synchronous malignancies were defined as a second diagnosis made at the sametime or fewer than 6 months after the diagnosis of the initial carcinoma. Metachronous malignancies were those diagnosed morethan 6 months after the initial diagnosis of the primary cancer. In the patients with metachronous malignancies, the median intervalbetween diagnoses of the primary and secondary malignancies was 15.9 months. All patients were treated with either radiotherapyor surgery for their initial cancer.

Results: Ten patients presented with synchronous head and neck and esophageal cancer, and 22 patients developed metachronouscarcinomas. The median overall survival time for the total group was 12.2 months. In patients with synchronous malignancies, themedian overall survival time was 13.8 months. In the group with metachronous malignancies, the medial overall survival time was9.6 months after diagnosis of the second malignancy. For patients with an initial diagnosis of head and neck cancer as the primarycancer, the median overall survival s time after the diagnosis of metachronous esophageal cancer was 8.2 months. For metachro-nous esophageal cancer, surgery provided a better result in overall survival and local control when compared with radiotherapy (p\ 0.05). In contrast, for patients with an initial diagnosis of esophageal cancer as the primary cancer, the median overall survivaltime after the diagnosis of metachronous head and neck cancer was 13.6 months. No difference was observed between the surgeryand radiotherapy groups in overall survival and local control of the metachronous head and neck cancer.

Conclusions: The development of synchronous or metachronous head and neck/esophageal cancer was associated with a pooroutcome. For patients with metachronous esophageal cancer, our data indicated that surgery might be more beneficial than radio-therapy.

Author Disclosure: C. Hsu, None; C. Wang, None; J. Cheng, None.

2586 Patterns of Local Failure for Patients with Head and Neck Squamous Cell Carcinoma Treated with

Intensity Modulated Radiation Therapy and Simultaneous Integrated Boost Technique

A. Hussain, C. S. Lin, P. Lee, G. Juillard, J. J. DeMarco, S. P. Lee

UCLA Department of Radiation Oncology, Los Angeles, CA

Purpose/Objective(s): By emphasizing precise target volume delineation, highly conformal radiation treatment using intensity-modulated radiation therapy (IMRT) may shift the location of local disease relapse from centrally within the tumor bulk to theperiphery. This study aims to evaluate patterns of local failure specifically among patients with locally-advanced head and necksquamous cells carcinoma (HNSCC) treated with IMRT and simultaneous integrated boost (SIB) technique.

Materials/Methods: The records of 24 patients presenting with primary HNSCC and treated at UCLA from July 2007 throughOctober 2008 were reviewed. The study population included: 16 male (67%), 8 female (33%), 4 stage II (17%), 4 stage III(17%) and 16 stage IV (67%). The primary tumor sites were: oropharynx in 11 patients, larynx 4, nasopharynx 3, hypopharynx2, oral cavity 2, paranasal sinus 1, and unknown in 1 patient. Twenty of the 24 patients (83%) received definitive RT, while theremaining 4 were treated post-operatively. Twenty-one (88%) patients received chemotherapy during the RT course. Medianprescription doses for planning target volume (PTV) levels 1, 2 and 3 were 69.3 Gy, 62.7 Gy and 56.1 Gy, respectively, givensimultaneously over 33 fractions.

Results: The median follow-up duration was 22.4 months (range: 7.9 - 36.6). Disease-specific and overall survival rates at 3 yearswere 100%. The actuarial local control probability was 83% at 3 years. Four (17%) patients failed to achieve local control of theirdisease, with 3 having oropharynx and one having hypopharynx primary. All 4 recurrent tumors were detected by either imaging(2) or biopsy (2), and occurred within the planning target volumes, not outside or at the periphery. The median time from the end ofRT to recurrence was only 4.8 months (range: 4.1 - 5.2), raising the possibility of persistent but inconspicuous residual diseaseversus true recurrences. All patients with local failure received salvage chemotherapy, with one also receiving RT and anotherundergoing neck dissection.

Conclusions: IMRT with SIB technique for HNSCC can achieve high rates of locoregional control and does not seem to portenda tendency for geographic miss. The predominant centrally-located failure pattern calls for further need of dose escalation. Preciseanatomic delineation as well as judicial use of fractionation scheme for the PTV design is critical when utilizing SIB technique.

Author Disclosure: A. Hussain, None; C.S. Lin, None; P. Lee, None; G. Juillard, None; J.J. DeMarco, None; S.P. Lee, None.

2587 High Late Complication and Local Control: An Experience with Hypofractionated Boost in the Treatment

of Head and Neck Cancer

Y. Kim, S. Son, S. Lee, J. Jang, B. Choi, H. Jang, S. Yoon, M. Kim, J. Kang, S. Jung

Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea

Purpose/Objective(s): Local control is an important prognostic factor for long-term disease control in advanced head and neckcancer. Fractionated stereotactic radiotherapy (FSRT) boost may improve local control with increased delivered radiation dose.However, FSRT with large fractional dose needs more experiences and longer follow-up to define potential long-term complica-tions. We report on the clinical outcome of CyberKnife radiosurgery (CKS) boost after external RT for locally advanced head andneck cancer with emphasis on unexpected high, late complications.

Materials/Methods: Twenty-seven patients were treated with curative external radiation therapy, followed by CKS boost forlocally advanced head and neck cancer. CKS boost sites were as follows : 10 nasopharynx, 5 maxillary sinus, 4 nasal cavity, 5peri-orbit, 3 tongue, and 1 oropharynx. Age range was 10-83 years old (median 55 years old). Nineteen patients (70.4%) receivedcombined chemotherapy sequentially or concomitantly. The administered ERT dose before CKS was 36-70Gy (median 50Gy) tothe CTV. GTV of high tumor burden or residual tumor were boosted to the dose of 10-27 Gy with the 70-80% (median: 80%)isodose line in 3-5 fractions. GTV volume ranged from 6.8�69.4cc (median 27.8 cc). Follow-up durations were 12.8�64.6 M(median 40.2 M).