P314 Sarcomas of the skull base: a complex cure approach and treatment results

226 maxillary sinus; with free disease period we found a similar percentage comparing all subsites. Keywords: adenoid cystic carcinoma, head and neck, salivary glands P312 Major salivary gland carcinoma UICC TNM classifications 1987 1992 1997 2002: evaluation of survival prediction and suggested changes for 2007 V. van der Poorten1 *, A. Hart2 , H. Lubsen3 , C. Terhaard3 , A. Balm2 . 1 University Hospitals Leuven, Belgium, 2 The Netherlands Cancer Institute Amsterdam, The Netherlands, 3 University Medical Center Utrecht, The Netherlands, 4 Dutch Head and Neck Oncology Group, The Netherlands Introduction: In the last two decades, an evolution in the definition of the levels of the TNM classification and the stage grouping guidelines has been observed. These changes have been driven by empirical observations. We wanted to evaluate the prognostic effect of these changes in a patient group from a nationwide database in the Netherlands. Patients and Methods: In a group of 231 patients with major salivary gland carcinoma treated by the members the Dutch Head and Neck Oncology Group with a median follow-up of 68 months and a 5 year disease specific survival of 74% (SE 3%), the stage grouping criteria of the subsequent 1987 through 2002 editions of the UICC TNM Classifications were applied. Also the suggestions to relocate T4N0M0 and T3N1M0 from Stage IV to Stage III disease (Numata et al, 2000) were analysed. Using Kaplan Meier survival analysis for overall survival, observations were made on distribution, discrimination, correct ordering and concordance. Results and Conclusion: Suboptimal distribution and discrimination is observed when classifying patients according to the 1987 1992 UICC guidelines. Using the 1997 UICC guidelines an improved discrimination is observed, but Stage III is found to be nearly empty (3% of patients). Following the proposal of Numata in the patients of the Dutch Head and Neck Oncology group, a clearly better distribution and discrimination results, dealing adequately with the stage III problem in the 1997 classification. The 2002 UICC guidelines result in an upstaging of patients belonging to Stage I in earlier editions, but still leave much to be desired as to discrimination and distribution. A combination of the changes proposed in the 2002 UICC edition and the changes proposed by Numata produces a superior discrimination and distribution in our patient group and seems the way to go in the future. Keywords: parotid, carcinoma, TNM classification, survival P313 Transcervical resection of parapharyngeal pleomorphic adenomas A. Poon *, B. Bell, J. Potter, B. Potter, E. Dierks. Legacy Emanuel Hospital, USA Parapharyngeal tumors are rare and constitute less than one percent of all head and neck tumors. Among them, pleomorphic adenoma is most common (40%), followed by paraganglioma (20%), neurogenic tumors (14%), and malignant salivary tumors (13%). Pleomorphic adenomas in the parapharyngeal space can either arise as primary tumors independent of the deep lobe, or as extensions of primary deep lobe parotid tumors. Numerous surgical approaches have been described, including transparotid, transoral, transcervical, cervical transpharyngeal, infratemporal fossa, and the parotidcervical approach with or without lip-split and mandibulotomy. Of these, the parotid-cervical approach combined with lipsplit and mandibulotomy provides the best access and thus potentially enables comprehensive tumor removal to minimize recurrence. Nevertheless, this technique is also associated with significant risks including injury to the facial nerve, compromised cosmesis, as well as morbidities from

Poster abstracts, Sunday 20 May the osteotomies. The transcervical technique, on the other hand, represents a low morbidity approach for removing parapharyngeal pleomorphic adenomas. While the risk of recurrence may be higher compared with tumor removal via the parotid-cervical approach, repeat transcervical resections can be carried out without much added risk or morbidity. We present a series of six cases of pleomorphic adenoma of the parotid gland involving the parapharyngeal space, resected via a transcervical approach with sparing of the superficial lobe and the facial nerve. None of the patients experienced facial nerve paresis or paralysis, whether transient or permanent. Duration of follow-up ranged from one month to eight years; no recurrence has been detected in any of the patients. Keywords: Parapharyngeal, Pleomorphic adenoma, Transcervical P314 Sarcomas of the skull base: a complex cure approach and treatment results A. Mudunov, E. Matyakin *. Blokhin’s Cancer Research Center, Russia Introduction: tumors spreading into the skull base demand combined surgical intervention. Sarcoma is a rare tumor type of this origin. We introduce our treatment experience in this group of patients (pts). Methods: 388 pts with different tumor sites involving the skull base: paranasal sinuses 185 (47.7%), orbita 9 (2.3%), infratemporal fossa 194 (50%). 214 (55.2%) with varying malignant tumors and 174 (44.8%) benign tumors. 86 (22.2%) presented with different types of sarcoma (osteosarcoma, PNET, chondrosarcoma, rhabdomyosarcoma, etc.). 73 (34.1%) received induction chemoradiotherapy (50 Gy) with 30% of complete clinical response. 82 (38.3%) received only preoperative radiotherapy (50 Gy) with 3.3% of complete clinical response. Surgery performed in 338 (87.1%) cases. Results: external neck approach was the main procedure for removal of tumors arises from infratemporal fossa 187 (55.3%). This kind of approach combined with lateral or median mandibulotomy and further miniplates osteosynthesis 25 (13.4%) mainly with sarcomas. We preferred musculocutaneus flap with major pectoral muscle for lateral pharyngeal wall reconstruction 5 (1.5%). Combined operations carried out in 92 (27.2%) cases. Transfacial approach was the main procedure for one side or bilateral maxillectomy, resection of the orbita, ethmoidal cells, frontal and sphenoid sinuses. In case of intracranial tumor spreading we used combined craniofacial approach 42 (12.4%). Bifrontal craniotomy was the main procedure in this kind of operations. Pericranial flap, split bone graft and biocomposite ceramics were the main plastic materials for reconstruction of the skull base. 38 (44.2%) pts with different types of sarcoma lived over a 5-year period after the treatment. Local recurrences appears in 35 (40.7%), distant metastases in 13 (15.1%) cases. Discussion: sarcomas spreading into the skull base presented with a high malignant tumor forms demanded aggressive cure tactic. Complex treatment approach should be performed in this patient group. Postoperative radiotherapy is preferable in cases of chemoresistant tumors. Thorough preoperative planing of surgery approach and total diagnostic picture ensure successful results. Keywords: Sarcomas, Skull Base, Surgery, Complex Approach