儿童侧颅底肿瘤的诊断和治疗

目的:探讨儿童侧颅底肿瘤的临床特点、诊断及治疗方法.方法:回顾性分析8例儿童侧颅底肿瘤的临床表现、影像学特点及治疗方法.其中颞部并中、后颅窝巨大三叉神经鞘膜瘤1例.颞部并中、后颅窝黑色素神经外胚层肿瘤1例,婴幼儿颞骨纤维瘤病1例,斜坡脊索瘤1例,鼻咽部胚胎型横纹肌肉瘤2例,神经母细胞瘤2例.1例经颞下窝Fisch C型及迷路上联合径路、1例经岩骨径路、4例经颞下窝Fisch C型径路将肿瘤全切除,1例经腭径路行肿瘤次全切,1例单纯行化疗未做手术.7例手术患儿中4例术前、术后化疗,3例术后化疗.结果:除1例脊索瘤患儿术后5个月复发死亡外,其余7例患儿均存活(6例手术、1例未手术),其中2例鼻咽部胚胎型横纹肌肉瘤术后小灶复发,1例神经母细胞瘤化疗后未行手术的患儿,6个月后复发.除术前1例外展神经、3例三叉神经受累及外,术后2例出现短暂脑脊液漏,1例同侧听力丧失.1例声嘶(同侧声带外展麻痹),2例吞咽困难,术后3～4个月渐恢复.7例手术患儿均无伤口感染裂开及皮瓣坏死,未出现面瘫、脑膜炎及偏瘫、死亡等严重并发症.结论:儿童侧颅底肿瘤生长部位深在、临床症状复杂多样、隐匿、不典型,往往确诊时已为晚期,积极行CT和MRI检查有助于提高早期诊断率.手术切除肿瘤仍为首选,手术前后配合放、化疗.手术径路的选择应依据病变的部位和范围,颞骨和颞下窝联合径路可以最大限度切除侵及该区域的肿瘤,保存脑神经功能,减少并发症.     

颞骨和颞下窝联合入路侧颅底肿瘤切除术

探讨安全和彻底摘除广侵侧颅底及其相邻区的肿瘤的手术入路和方法。方法通过颞骨和颞下窝联合入路,应用显微外科技术摘除肿瘤,并尽可能维护或重建颅底和颅神经。     

颅面拆装入路颅底肿瘤切除术(附62例报告)

目的探讨颅面拆装入路在颅底区肿瘤切除术中的应用.方法根据肿瘤侵犯范围分别采用额鼻拆装、上颌窦壁拆装、全上颌骨拆装、下颌骨拆装、颞颧拆装、颞颧一下颌骨拆装等技术,共施行颅底肿瘤摘除62例.其中良性肿瘤15例,恶性肿瘤47例.结果良性肿瘤术后无复发.恶性肿瘤术后3年生存率为62.0%,5年生存率为38.3%.结论应用颅面拆装方法摘除颅底区肿瘤,术野暴露较充分,有利于病灶的完全切除,颅底重要结构可得到保护,并能较好地恢复面部的形态和功能.     

10例前颅底肿瘤的术式分析

目的：探讨鼻锥体下翻额正中进路前颅底肿瘤切除术在前颅底肿瘤中的应用。方法：颅面联合进路前颅底肿瘤切除术2例；经额下进路颅-眶-鼻沟通性肿瘤切除术3例；鼻侧切开术3例；鼻锥体下翻额正中进路前颅底肿瘤切除加额骨膜、髂骨瓣颅底修复和重建2例。结果：10例患者均完全切除瘤体，经1～5年随访，良性肿瘤6例无复发。恶性肿瘤4例中，1例随访1年生存良好；余3例中生存3年2例，5年1例。结论：前颅底肿瘤需要根据肿瘤的大小、位置及性质选择最佳的手术进路。鼻锥体下翻额正中进路前颅底肿瘤切除术可在明视下进行手术操作，对额叶损伤轻，颅底修复方便，是一有价值的手术进路。     

Skull base surgery for removal of temporal bone tumors

CONCLUSION: When selecting the appropriate surgical approach the pathological type of tumor, the physiological status as well as the functional aspects should be considered. Understanding the strengths and weaknesses of each surgical technique and knowledge of the particular tumor biology facilitates selection of the most appropriate surgical approach and a successful outcome. OBJECTIVES: The purpose of this study was to review cases that underwent skull base surgery for a variety of tumors that involved the temporal bone. We reviewed a single center's 25-year experience for epidemiologic characteristics, symptoms, treatment type and outcomes. PATIENTS AND METHODS: The medical records and radiological images of 91 patients, who underwent skull base surgery, were retrospectively reviewed. RESULTS: Among the 91 patients, 61 cases had benign disease and 30 had malignancies. A facial nerve schwannoma was the most common benign intratemporal tumor and a squamous cell carcinoma was the most common malignant tumor. With the facial nerve schwannoma, facial nerve paralysis and hearing loss were the most common presenting complaints; otalgia was the most common presenting symptom for temporal bone cancer. For patients with a glomus tumor, there was a characteristic pulsating tinnitus. A majority of the facial nerve schwannomas were resectable through the transmastoid approach. The infratemporal fossa approach type A was usually required for lower cranial nerve schwannomas and glomus jugulare tumors. However, the fallopian bridge technique with hypotympanectomy was another surgical option. Partial temporal bone resection and subtotal temporal bone resections were performed in cases with temporal bone cancer. The disease free 5-year survival of the temporal bone cancers was 42% and for the squamous cell carcinomas, it was 44%.     

儿童颅底肿瘤经鼻内镜外科手术治疗分析

摘要：目的探讨分析鼻内镜手术在治疗儿童颅底肿瘤中的应用。 方法回顾性分析中南大学湘雅医院鼻颅底外科 2010年6月—2019年11月收治确诊为颅底肿瘤并行鼻内镜治疗的患儿共44例,其中鼻咽纤维血管瘤17例,朗格汉斯组织细胞增生症7例,骨化纤维瘤5例,原始神经外胚层肿瘤2例,横纹肌肉瘤2例,脑膜瘤2例,间叶性软骨错构瘤1例,颅咽管瘤1例,表皮样囊肿1例,血管纤维脂肪瘤1例,生殖细胞瘤1例,骨母细胞瘤1例,脊索瘤1例,侵袭性垂体腺瘤1例,纤维瘤病1例。 结果44例患儿中43例在鼻内镜下完全切除,仅1例鼻咽纤维血管瘤分期切除。术后44例均进行定期随访,随访时间3个月至9年。5例失访,其中骨母细胞瘤1例,脑膜瘤1例,横纹肌肉瘤1例,鼻咽纤维血管瘤2例;12例术后接受放化疗,其中朗格汉斯组织细胞增生症7例,原始神经外胚层肿瘤 2例,横纹肌肉瘤1例,脊索瘤1例,生殖细胞瘤1例,随访至今患儿状况良好,均无复发及转移;1例鼻咽纤维血管瘤复发;再次手术后治愈;其余26例患儿术后未见复发。结论鼻内镜颅底手术治疗儿童颅底肿瘤是可行、有效及安全的。     

颅中窝-侧颅底沟通性恶性肿瘤的手术治疗

目的 探讨颅中窝．侧颅底沟通性晚期恶性肿瘤的手术治疗方法。方法 16例颅中窝-侧颅底沟通性恶性肿瘤分别采用了：①耳后“C”形切口,颞骨次全切除进路与高位颈侧切开联合进路行颅中窝-侧颅底和腮腺区肿瘤切除6例;②颞侧舌形切口,颅中窝进路颅内外肿瘤切除4例;③颞-耳-下颌骨外旋进路行咽旁、颞下窝、颅中窝肿瘤切除6例。其中13例术后进行放射治疗。结果 16例中11例术后存活3年以上,5例术后3年内死亡。按寿命表法统计,3年生存率为69％。结论 本组所采用的三种手术方式,能较好地暴露颅内外病变,并进行肿瘤切除。对颅底区晚期恶性肿瘤采用手术及术后放射治疗等积极措施可取得一定的治疗效果。     

颞下窝B型径路切除侧颅底肿瘤临床分析

目的探讨颞下窝B型径路在侧颅底肿瘤中的适应证及手术效果。 方法回顾性分析2015年1月—2018年6月采用颞下窝B型径路治疗8例侧颅底肿瘤患者的临床资料,其中横纹肌肉瘤1例,成熟型畸胎瘤1例,骨巨细胞瘤1例,颞骨鳞癌1例,巨细胞修复性肉芽肿2例,胆脂瘤2例。结果3例患者病变范围主要累及颈静脉孔区、颈内动脉、岩尖;5例患者病变范围主要累及颧弓、颞下颌关节、中颅底甚至颞叶。7例单纯行颞下窝B型径路,1例患者行颞下窝B型径路联合经耳蜗径路,8例患者均完全切除病变。所有患者术后1周复查头颅MRI,均未见病变残留。4例患者术后为重度传导性或混合性听力下降,另外4例患者术后为极重度感音神经性听力下降。术前面瘫者2例,术后无加重;术前面神经功能正常者,术后2例出现面瘫,其中1例为联合经耳蜗入路患者术中将面神经进行移位,另外1例由于恶性肿瘤已侵犯面神经,术中将受侵犯的面神经切除。所有患者随访期间均无脑脊液耳漏、颅内出血,颅内感染、偏瘫、死亡等严重术后并发症。 结论颞下窝B型径路在暴露颈内动脉垂直段和水平段、岩尖等部位极具优势,同时这一径路也可用于切除累及颧弓、颞下颌关节甚至累及颞叶的侧颅底肿瘤。     

颅内外沟通性肿瘤的外科治疗

目的 探讨颅内外沟通性肿瘤的外科治疗。方法 统计分析我院自2001年1月至2005年5月治疗的32例颅内外沟通性肿瘤,其中恶性肿瘤22例,良性肿瘤10例,20例进行颅面联合进路肿瘤切除;10例在鼻内镜辅助下开颅手术切除;2例行颅外进路肿瘤切除,对颅底缺损的修复用帽状腱膜-颅骨骨膜瓣、颞肌-肌筋瓣、颅骨骨瓣、前臂皮瓣等。结果 22例恶性肿瘤中随访2年以上6例,1～2年8例,1年以下7例,1例死亡,1例脑转移带瘤生存,其余均健在。10例良性肿瘤无复发。结论 对颅内外沟通性肿瘤,应根据肿瘤的位置、大小及颅内累及的情况,选择合适的手术人路,在保证肿瘤切除彻底的前提下,尽可能的减小损伤,对部分颅内外沟通性肿瘤,鼻内镜辅助下手术,可减小创伤,同时面部无疤痕。     

Surgical management of skull base chondroblastoma

OBJECTIVES: Chondroblastoma is a rare tumor accounting for 1% of primary bone tumors. Chondroblastoma involving the skull base is exceedingly rare with approximately 60 cases reported. We reviewed our experience with chondroblastoma of the skull base with an emphasis on current lateral skull base approaches and long-term tumor control. STUDY DESIGN AND SETTING: A retrospective case review at a tertiary neurotology private practice group was performed over a 20-year period. Five patients were identified with skull base chondroblastoma. All patients underwent surgical intervention, and success of surgery was determined by disease-free status at last follow-up. Mean follow-up time was 5.8 years. RESULTS: Two patients underwent gross tumor removal as primary therapy. One patient underwent partial tumor removal at an outside institution, and follow-up magnetic resonance imaging demonstrated rapid growth of residual tumor. This patient was successfully treated with gross total removal of residual tumor with an infratemporal craniotomy approach. Near total tumor removal was performed in two patients because of intimate involvement of vital structures. At last follow-up, no patient had radiographic evidence of tumor recurrence. There were no significant postoperative complications. CONCLUSIONS: Gross total or near total resection of skull base chondroblastomas through lateral skull base approaches results in long-term tumor control and low complication rates.     

Revision lateral skull base surgery.

OBJECTIVE: To describe functional and reconstructive results after revision lateral skull base surgery with comparison of benign and malignant lesions. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: All patients undergoing revision surgery for benign and malignant lateral skull base tumors. INTERVENTIONS: Surgical resection of recurrent lateral skull base tumors and reconstruction of resulting defects. MAIN OUTCOME MEASURES: Cranial nerve function postoperative complications. RESULTS: Forty operations for recurrent lateral skull base tumors occurred between January 1, 1987, and December 31, 2003, with follow-up of at least 1 year. Thirty-three operations were for benign lesions, 27 of which were glomus tumors. Seven operations were for malignant tumors. Fifty-eight percent of patients had preoperative cranial nerve deficits (66% of benign tumors and 14% of malignancies). The most common preoperative deficit occurred in the Xth cranial nerve. Postoperative cranial nerve deficits were seen in 95% of patients and multiple nerve deficits were seen in 75%. The most common postoperative deficits were observed in the IXth and Xth cranial nerves. Thirty-one patients had one previous procedure, six had two previous procedures, and three had three previous procedures. Abdominal fat and temporoparietal fascia were the most common reconstruction materials. There was one case of meningitis, two cerebrospinal fluid leaks, and one pseudomeningocele. There was one recurrent adenoid cystic tumor resulting in death and two partially resected glomus tumors. Subsequent procedures are discussed. CONCLUSION: Postoperative cranial deficits are more common after revision skull base surgery than after primary surgery. Complete resection without recurrence can be expected for revision skull base surgery. Modern reconstruction techniques reduce major postoperative complications and morbidity from cranial nerve deficits.     

累及颅底肿瘤的手术切除与入路选择

目的　探讨颅底肿瘤切除的最佳手术入路。方法　回顾分析 1993～ 2 0 0 0年中国医学科学院中国协和医科大学肿瘤医院外科处理侵及颅底肿瘤 84例的经验 ,讨论侵及颅底不同部位病变手术入路特点 ,以求选择最好的手术入路彻底切除肿瘤 ,同时尽量保护颅底、颅内重要结构 ,减少并发症。结果　患者年龄 6～ 78岁 ,平均 4 3 8岁。良性肿瘤 14例 ,恶性肿瘤 70例。采用各种手术入路切除累及咽旁颅底肿瘤 38例 ;同时有前、中颅底破坏 7例 ;肿瘤同时累及中、后颅底 13例 ;侧颅底颞下窝肿瘤 2 6例。用各种组织瓣修复颅底缺损或填充 6 0例。 6例并发脑脊液漏 ,2例迟发脑脓肿 ,修复组织瓣部分坏死 3例 ,无手术死亡及严重颅脑并发症。恶性肿瘤 3年生存率 6 7 5 % (2 7/ 4 0 )。结论　最佳手术入路的选择应相对于颅底不同部位的肿瘤 ,针对特殊的解剖结构而选择 ,可以根据以下几个因素综合考虑 :①肿瘤部位及累及的范围 ;②安全、充分地切除肿瘤 ;③正常功能结构及外观影响小 ;④便于可靠有效地修复     

涉及颅底咽旁间隙肿瘤的治疗

目的:探讨涉及颅底咽旁间隙肿瘤处理的有效方法.方法:对2000年3月～2005年7月36例涉及颅底咽旁间隙肿瘤患者资料进行回顾性分析.采用的手术入路分别是:经颈侧切开入路15例,经颈-腮腺入路10例,下颌骨外旋入路4例,上颌外旋入路5例,眶颧入路2例.结果:36例肿瘤中,5例为恶性肿瘤,其余皆为良性肿瘤.31例良性肿瘤皆完整切除.5例恶性肿瘤中有2例为鼻咽黏膜下型鳞状细胞癌颅底咽旁间隙转移,经颈侧切开探查病理确诊后放射治疗,1例随诊3年无复发;1例随诊5年,复发带瘤生存;1例侵犯颅底的恶性神经纤维瘤术后3年复发,放弃治疗死亡;1例侵犯颅底的恶性神经鞘膜瘤术后已随诊3年余,健在;1例腮腺深叶黏液表皮样癌,已随诊2年余,健在.36例中,术后声嘶者3例伴呛咳1例,4例发生Horner综合征;2例发生舌偏斜,3个月后好转.结论:不同的涉及颅底咽旁间隙肿瘤有不同的临床特点,应根据各自的临床特点选择适当的处理方法.     

头颈外科神经外科联合手术治疗颅底沟通肿瘤

目的 介绍头颈外科与神经外科合作处理颅底沟通肿瘤的经验和优势.方法 回顾性分析2005年7月至2008年7月头颈外科和神经外科联合制定手术方案并共同实施手术54例(良性21例,恶性33例)颅底沟通肿瘤的临床资料,其中前颅底19例,侧颅底12例,中央颅底17例,后颅底(颈静脉孔区)6例.结果 本组颅底沟通肿瘤均一期手术切除.良性肿瘤全切除20例,近全切除1例;恶性肿瘤肉眼全切除25例,6例鼻窦、鼻咽、腮腺恶性肿瘤及2例脊索瘤近全切除.无手术死亡病例,恶性肿瘤并发症13例,其中术后出血2例.随访8～43个月,良性与恶性肿瘤中位随访时间分别为19.1及21.0个月,恶性患者失访3例.21例良性肿瘤复发1例.33例恶性肿瘤中复发12例,死亡9例(其中1例死于心脏病),Kaplan-Meier法统计3年生存率与无瘤生存率分别为53.0%及52.7%.结论 头颈外科和神经外科合作有利于提高颅底沟通肿瘤的手术切除率从而提高治疗效果.     

颅面拆装入路广泛性颅底肿瘤手术(附10例报告)

目的：探讨颅面拆装入路在颅底广泛性肿瘤切除术中的应用。方法：10例范围广泛的颅底区肿瘤分别采用了额鼻拆装,颅面联合入路;上颌窦壁拆装,上颌窦鼻腔入路;颞颧下颌骨拆装,颞面联合入路等3种手术方式切除。结果：2例良性肿瘤术后随访1～3年无复发。8例恶性肿瘤术后,5例已存活3年以上,其中3例已存活5年以上;另3例均在术后3年内死亡或失访,结论：采用颅面拆装入路施行颅底肿瘤切除术,术野暴露较充分,有利于病灶的完全切除,颅底的重要结构可得到保护,并能较好地恢复面部的形态和功能。     

累及颅底肿瘤的手术切除与入路选择

目的 探讨颅底肿瘤切除的最佳手术入路。方法 回顾分析1993－2000年中国医学科学院中国协和医科大学肿瘤医院外科处理侵及颅底肿瘤84例的经验，讨论及颅底不同部位病变手术入路特点，以求选择最好的手术入路彻底切除肿瘤，同时昼保护颅底、颅内重要结构，减少并发症。结果 患者年龄6－78岁，平均43．8岁。良性肿瘤14例，恶性肿瘤70例。采用各种手术入路切除累及咽旁颅底肿瘤38例；同时有前、中颅底破坏7例；肿瘤同时累及中、后颅底13例；侧颅底颞下窝肿瘤26例。用各种组织瓣修复颅底缺损或填充60例。6例并发脑脊液漏，2例迟发脑脓肿，修复组织瓣部分坏死3例，无手术死亡及严重颅脑并发症。恶性肿瘤在3年生存率67．5％（27／40）。结论 最佳手术入路的选择应相对于颅底不同部位的肿瘤，针对特殊的解剖结构而选择，可以根据以下几个因素综合考虑：①肿瘤部位及累及的范围；②安全、充分地切除肿瘤；③正常功能结构及外观影响小；④便于可靠有效地修复。     

transcervical approach for resection of lateral skull base tumors

Objectives Conventional approaches for removal of lateral skull base tumors, including transmandibular, infratemporal fossa, preauricular transzygmatic subtemporal approaches, are major invasive procedures that often sacrifice hearing and cause abnormal occlusion and cosmetic defects. Reports of the transcervical approach for resection of skull base tumors are rare, although it was described for resection of clival chordomas in as early as 1966. The purpose of this study is to review our experiences in management of lateral skull base tumors using the transcervical approach. Study Design Retrospective chart review. Methods Six lateral skull base tumor cases treated with transcervical approach procedures were reviewed, including the medical records. Results There were 4 males and 2 females. Age ranged from 12 through 52 years. Histopathological diagnoses included malignant schwannoma(n = 1), malignant carotid body tumor(n = 1), heamangioma(n=1), schwannoma (n=2) and pleomorphic adenoma (n = 1). Transcervical techniques were used in all cases with the use of microscope in the lateral skull base area. Complete tumor removal was achieved in all cases. Postoperative radiotherapy was implemented in 1 case of malignant schwannoma and 1 case of malignant carotid body tumor. Jugular foramen syndrome occurred as a surgical complication in 1 case of malignant Schwannoma of the vagus nerve. There was no tumor recurrence during the 10 - 42 month follow-up period. Conclusion Compared with conventional approaches, the transcervical approach provides a easy, safe, minimal invasive and effective procedure for removal of selected lateral skull base tumors.     

前颅底肿瘤手术入路

目的：探讨前颅底肿瘤手术入路,提高手术效果。方法：对37例前颅底肿瘤进行了相应的手术切除,颅面联合入路21例,其中额颅合并鼻侧切开1例,上颌骨内侧部分切除或暂移开切除肿瘤7例,上颌骨切除8例,上颌骨或（和）眶或（和）颌面皮肤切除5例;上颌骨部分或全外旋合并鼻锥转位13例;鼻额翻瓣、额眶入路及面中揭翻各1例。结果：10例良性肿瘤患者均健在,恶性肿瘤患者3、5年存活率分别为81．9％（22／27）、62．9％（17／27）。9年以上无瘤存活1例。结论：除鼻侧切开外不同类型颅面联合入路均能提供良好的肿瘤显露,有利于鼻颅沟通瘤的整块切除。部分或上颌骨全外旋合并鼻锥转位适于切除累及颅底尚未侵及颅内的肿瘤。额鼻共同翻开适于切除额窦发育良好的鼻颅沟通瘤。颅眶入路适于颅眶沟通瘤。面中揭翻应选择应用。     

小涎腺肿瘤的外科治疗

目的:分析和探讨小涎腺肿瘤的临床特征和诊疗要点。方法:对我院1997～2004年收治的54例小涎腺肿瘤患者的临床特征和治疗效果作回顾性分析。结果:54例患者中失访16例,在随访到的38例患者中,因肿瘤复发死亡4例,其中2例鼻腔腺样囊性癌分别于术后2年和3年死于肿瘤复发,1例喉肌上皮癌术后3年死于肿瘤复发,1例鼻窦黏液表皮样癌术后1年5个月死于肿瘤复发;2例鼻窦腺样囊性癌术后复发,再次手术后无瘤生存;1例鼻腔腺样囊性癌术后11个月复发,行伽玛刀治疗及中药治疗带瘤生存;其余患者均无瘤生存。结论:小涎腺肿瘤分布广泛,病理类型繁多,本组病例以恶性肿瘤多见,占81.4%。不同部位的肿瘤和不同病理类型的肿瘤临床表现和治疗方案各不相同。对良性肿瘤多采用肿瘤摘除术。而对恶性肿瘤治疗,手术结合放疗是主要的治疗方案。成功的关键是完整地切除肿瘤和有足够的切缘。     

Chondrosarcoma of the skull base: long-term follow-up.

OBJECTIVE: Chondrosarcoma of the skull base is an uncommon neoplasm comprising 0.15% of all intracranial tumors and 6% of skull base neoplasms. The outcome of treatment is difficult to assess because the slow growth rate means that there is a long interval before detecting the recurrence. We describe the use of lateral skull base techniques for these lesions and examine the long-term outcomes. The pathological features, radiological findings, and radiotherapy options are also discussed. STUDY DESIGN: Retrospective case review with current follow-up where possible. SETTING: Tertiary referral neurotologic private practice. PATIENTS: Eight patients with histologically confirmed skull base chondrosarcoma operated on since 1979. At the time of the surgery, the five women and three men ranged in age from 31 to 63 years, with a mean of 42.9 years. The follow-up ranged from 9 months to 25 years and 5 months. INTERVENTIONS: All patients underwent surgical removal; the earliest patient underwent surgical removal via transcochlear and retrosigmoid approaches, and seven via an infratemporal fossa approach, with or without exenteration of the otic capsule. MAIN OUTCOME MEASURES: Number of patients with residual and recurrent tumors. RESULTS: In the patient who underwent surgery via the transcochlear approach, recurrence was noted within 3 months, and new exploration using the retrosigmoid approach was performed for the removal of the recurrent lesion. This patient showed no signs of recurrence for 25 years since last surgery. Of the seven patients who underwent surgery via the infratemporal fossa approach, one had residual tumor found at 1 year, but remained alive and well for 21 years after the surgery. The other six had gross total resection and showed no signs of recurrence at the last known follow-up. One patient died as a result of an unrelated cause 18 years after surgery for the chondrosarcoma. CONCLUSION: The gross total resection of these lesions is possible because of the evolution of lateral skull base techniques and can be routinely accomplished with the infratemporal fossa approach. The improved exposure afforded by this approach seems to have resulted in more complete extirpation of the tumor and a decrease in the recurrence rate.