Skull Base Invasion Research Articles

Prognostic factors in oral cavity cancer with skull base recurrence

Objective Recurred oral cavity cancer at the skull base is complicated to treat due to difficult surgical approach and possible dural invasion. Therefore, initial curative treatment is of most importance and it would be helpful to know cases that would likely recur before treatment. We tried to identify prognostic factors that can predict skull base recurrence after initial treatment, to find out cases that need more aggressive initial treatment. Methods This retrospective study was performed on 51 patients diagnosed as squamous cell carcinoma in the oral cavity, and they underwent surgery and adjuvant radiotherapy. Variables associated with clinical findings, imaging studies, and pathologic results were analyzed to identify factors related to skull base recurrence. Results Recurrences occurred in 21% (11) cases, and skull base invasion in 5 of these recurred cases. Tumor location, clinical T stage, retromolar trigone (RMT) invasion, bone invasion, perineural invasion, positive resection margin, endolymphatic tumor emboli, and medial and lateral pterygoid muscle invasion were found to be significant prognostic factors by univariate analyses. Among those factors, medial pterygoid muscle invasion and positive resection margin remained independent predictors of skull base recurrence with multivariate analyses by Cox regression. Conclusion Patients with medial pterygoid muscle invasion or a positive resection margin have a high risk of skull base invasion during tumor recurrence. Therefore, careful evaluation and aggressive management are needed to prevent skull base invasion in cases that recur.

Serum CCL2 and serum TNF-α – Two new biomarkers predict bone invasion, post-treatment distant metastasis and poor overall survival in nasopharyngeal carcinoma

PurposeTo evaluate the prognostic potential of serum CCL2 (sCCL2) and serum TNF-α (sTNF-α) in nasopharyngeal carcinoma (NPC) before treatment by analysing the expression of these two markers. Experimental designBoth sCCL2 and sTNF-α were prospectively detected in 297 NPC patients with enzyme-linked immunosorbent assay (ELISA) before treatment. The correlations between sCCL2 level or sTNF-α level and patient’s survival were evaluated. ResultsFor sCCL2, the 5-year overall survival (OS) and 5-year distant metastasis-free survival (DMFS) of high expression group and low expression group were 64% versus 81% and 67% versus 84% (P<0.05), respectively. For sTNF-α, the 5-year OS and 5-year DMFS of high expression group and low expression group were 62% versus 79% and 66% versus 82% (P<0.05), respectively. The 5-year OS and 5-year DMFS for both positive patients, one marker positive patient and both negative patients were 53% versus 77% versus 85% and 58% versus 80% versus 86% (P<0.05), respectively. Concentrations of sCCL2 and sTNF-α in patients with large skull base invasion were higher than those without or with small skull invasion (P<0.05). Patients who developed bone metastasis alone after radical treatment had higher pre-treatment concentrations of sCCL2 and sTNF-α than those without metastasis (P<0.001). Multifactorial Cox regression analyses demonstrated that T/N/M classification, chemotherapy, sCCL2 level and sTNF-α level were independent predictors of OS and DMFS of NPC patients. ConclusionHigh expression levels of sCCL2 and sTNF-α predict bone invasion, post-treatment distant metastasis and poor overall survival in NPC patients.

MRI study on the relationship between the invasion patterns and staging of nasopharyngeal carcinoma

Objective To investigate the peri-nasopharyngeal invasion patterns of nasopharyngeal carcinoma (NPC) on MRI and its relationship with tumor staging. Methods One thousand five hundred and seventy-three patients with newly diagnosed NPC which were histo-pathologically proved were retrospectively studied. The MRI manifestations and invasion patterns of the NPCs were elevated according to the 2008 Tstaging system of NPC. Z test was used to analyze the rate of adjacent structures invasion in NPCs. Results The structures invaded by NPCs included pharyngobasilar fascia in 1299 cases (82. 58% ); parapharyngeal space, 1090 ( 69. 29% ); nasal cavities, 304 ( 19. 33% ); oropharynx, 49 ( 3. 12% ); carotid space,514(32. 68% ); medial pterygoid muscle, 661 (42. 02% ); lateral pterygoid muscle, 210( 13. 35% ); skull base bones, 943(59. 95% ); cranial nerves, 630(40. 05% ) and paranasal sinuses, 242 ( 15.38% ). The T-stage distribution was T1, 242 cases ( 15.38% ); T2, 288 ( 18. 31% ); T3, 410 (26. 06% ) and T4,633 (40. 24% ). Among the cases with nasal cavities invasion, 90. 46% (275/304)showed the involvement of the structures seen in T3 or T4 stage, which was found in all cases with oropharynx invasion. In addition,69. 14% (457/661) of cases with medial pterygoid muscle invasion and 92. 15% (223/242) of cases with paranasal sinuses invasion showed the involvement of structures seen in T4 stage. As for the invasion patterns of NPC, the lateral invasion of pharyngobasilar fascia was more frequent than upward invasion of skull base (Z = 14. 025, P ＜ 0. 01 ) and downward invasion of oropharynx ( Z = 45.032, P ＜ 0. 01 ), and the downward invasion of oropharynx was less frequent than upward invasion of skull base ( Z = 34. 301, P ＜ 0. 01 ) and forward invasion of nasal cavities ( Z = 14. 404, P ＜ 0. 01 ). Conclusion NPC has a predilection of lateral invasion rather than upward and downward invasion, and its upward and forward invasion are more common than downward invasion. Key words: Nasopharyngeal neoplasms; Magnetic resonance imaging; Neoplasm staging

Prognostic significance and therapeutic implications of centromere protein F expression in human nasopharyngeal carcinoma

BackgroundOur recent cDNA microarray data showed that centromere protein F (CENP-F) is significantly upregulated in primary cultured nasopharyngeal carcinoma (NPC) tumor cells compared with normal nasopharyngeal epithelial cells. The goal of this study was to further investigate the levels of CENP-F expression in NPC cell lines and tissues to clarify the clinical significance of CENP-F expression in NPC as well as the potential therapeutic implications of CENP-F expression.MethodsReal-time RT-PCR and western blotting were used to examine CENP-F expression levels in normal primary nasopharyngeal epithelial cells (NPEC), immortalized nasopharyngeal epithelial cells and NPC cell lines. Levels of CENP-F mRNA were determined by real-time RT-PCR in 23 freshly frozen nasopharyngeal biopsy tissues, and CENP-F protein levels were detected by immunohistochemistry in paraffin sections of 202 archival NPC tissues. Statistical analyses were applied to test for prognostic associations. The cytotoxicities of CENP-F potential target chemicals, zoledronic acid (ZOL) and FTI-277 alone, or in combination with cisplatin, in NPC cells were determined by the MTT assay.ResultsThe levels of CENP-F mRNA and protein were higher in NPC cell lines than in normal and immortalized NPECs. CENP-F mRNA level was upregulated in nasopharyngeal carcinoma biopsy tissues compared with noncancerous tissues. By immunohistochemical analysis, CENP-F was highly expressed in 98 (48.5%) of 202 NPC tissues. Statistical analysis showed that high expression of CENP-F was positively correlated with T classification (P < 0.001), clinical stage (P < 0.001), skull-base invasion (P < 0.001) and distant metastasis (P = 0.012) inversely correlated with the overall survival time in NPC patients. Multivariate analysis showed that CENP-F expression was an independent prognostic indicator for the survival of the patient. Moreover, we found that ZOL or FTI-277 could significantly enhance the chemotherapeutic sensitivity of NPC cell lines (HONE1 and 6-10B) with high CENP-F expression to cisplatin, although ZOL or FTI-277 alone only exhibited a minor inhibitory effect to NPC cells.ConclusionOur data suggest that CENP-F protein is a valuable marker of NPC progression, and CENP-F expression is associated with poor overall survival of patients. In addition, our data indicate a potential benefit of combining ZOL or FTI-277 with cisplatin in NPC suggesting that CENP-F expression may have therapeutic implications.

Intraoperative control of resection margins in advanced head and neck cancer using a 3D-navigation system based on PET/CT image fusion

Local recurrent of disease in advanced carcinomas of the head and neck is strongly correlated with the presence of positive or close resection margins after operative treatment. The purpose of this study is to present a new method of assessing resection margins intraoperatively using image-guided surgery based on positron emission tomography/computed tomography (PET/CT) image fusion. In 6 patients who underwent surgical treatment of head and neck stage for T4a-T4b carcinomas PET/CT image fusion was done on the workstation of a 3D-navigation system. Intraoperative image-guided navigation of the defect following surgical ablation of the tumour was performed in every patient. Intraoperative navigation of the ablative defect showed an unsafe resection margin in 4 patients. In three of these patients additional image-guided resection allowed local control of the tumour to be achieved. In one patient additional resection was not possible due to skull base invasion. The histopathological exam of the four tumour specimens confirmed positive or close resection margins. The current results suggest that intraoperative control of the surgical margins using a 3D-navigation system based on PET/CT image fusion can be a useful tool to assess and improve local control in advanced cancer of the head and neck.

Juvenile nasopharyngeal angiofibroma: endoscopic surgery and follow-up results

To present the changes of surgical approaches for the resection of juvenile nasopharyngeal angiofibromas (JNA) and the follow-up results. The clinical records of 59 patients with JNA treated under endoscope between 2002 and 2009 were reviewed retrospectively. The patients were divided into two groups: Group A (Radkowski I a-II b) and Group B (Radkowsik II c-III b). The tumor stages, feeding vessels, operating time, complications and recurrence were observed and recorded. There were 7 patients with stage I a, 3 patients with stage I b, 5 patients with stage II a, 6 patients with stage II b, 4 patients with stage II c, 23 patients with stage III a, 11 patients with stage III b. The average age at diagnosis in Group A (21 cases) was 23.9 years old. The average operating time was (106.0 +/- 43.7) min. The follow-up ranged from 3 months to 74 months (median 36 months) except for 3 missing cases. The average age at diagnosis in Group B (38 cases) was 16.2 years old and the average operating time was (152.9 +/- 58.0) min. The follow-up ranged from 3 months to 87 months (median 25 months) except for 5 missing cases. During follow-up, 6 patients in group B recurred. Infarction of thalamencephalon happened in 1 patient in group B who recovered totally afterwards. The difference in operating time between two groups was statistically significant (t = -3.232, P = 0.002). The life table was used to evaluate the survival curves and Log-rank test showed that the difference of recurrent time between two groups was statistically significant (P = 0.03). The key techniques to remove tumor are bleeding control, drilling-out the bone that tumor invaded. Transpterygoid or posterolateral wall of maxillary sinus approach are recommended for tumors that extend to infratemporal fossa. Small and intermediate-sized JNA which have no deep invasion of skull base (RadkowskiIa-II b) have a low morbidity. JNA at Radkowski stage IIc and above have residual and recurrent risk.

CT-MR image fusion in the delineation of gross target volume for nasopharyngeal carcinoma

Objective To compare the accuracy and feasibility among CT, MR, and CT-MR image fusion technology in the delineation of gross target volume (GTV) for nasopharyngeal carcinoma (NPC). Methods Thirty-six consecutive patients with newly diagnosed or recurrent NPC were enrolled. Each pa-tient underwent both CT and MR scanning in the same treatment position. Several lead marks were made at the exactly same locations of the body surface before CT and MR scanning. The two sets of images were then transferred to the Tomcon workstation for image fusion. CT-MR image registration was performed using Land-Mark methods. GTV of each patient was contoured on CT (GTV_(CT)), MR (GTV_(MR)) and CT-MR (GTV_(CT-MR)) images. Results The mean GTV_(CT), GTV_(MR) and GTV_(CT-MR) were 27.60 cm~3, 30.99 cm~3 and 31.71 cm~3, respectively (F = 7.48, P = 0.001). Significant difference was found between GTV_(CT) and GTV_(MR) (q =2.54,P=0.016), GTV_(CT) and GTV_(CT-MR) (q =3.10,P =0.004), but not GTV_(MR) and GTV_(CT-MR) (q = 1.31 ,P = 0. 199). Significant difference among GTV_(CT), GTV_(MR) and GTV_(CT-MR) was found in patients with skull base invasion (35.65, 42.70 and 44.22 cm~3 ; F = 14. 13, P = 0. 000), but not in those without skull base invasion (20.79 cm~3, 20.46 cm~3 and 21.18 cm~3 ; F = 0.18, P = 0.832). Significant difference between GTV_(CT) and GTV_(CT-MR) was found in patients with T_3 and T_4 tumor (t = -2.17,P =0. 036), but not in those with T_1 and T_2 (t = -0.66 ,P = 0.514). Conclusions CT-MR image fusion is helpful in GTV de-lineation for NPC, particularly for patients with skull base invasion. Key words: Nasopharyngeal neoplasms/radiotherapy; Target delineation; Image fusion

Horner Syndrome as a Presenting Sign of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma is generally diagnosed prior to ophthalmic complaints. The authors present a case of a 57-year-old healthy man with sudden-onset unilateral ptosis. MRI showed an ulcerating soft-tissue mass in the nasopharynx with skull base invasion. Biopsy confirmed nasopharyngeal carcinoma.

Comparison of diagnostic value of PET using 18-fluoro-2-deoxyglucose, CT and MRI in detecting skull base invasion of nasopharyngeal carcinomas

Objective We compared positron emission tomography (PET) using 18-fluoro-2-deoxyglucose (FDG), enhanced computed tomography (CT) and magnetic resonance imaging (MRI) in detecting skull base invasion of nasopharyngeal carcinomas (NPC) and to evaluate the value of these three methods in determining the existence of skull base invasion of nasopharyngeal carcinomas.

Imaging of nasopharyngeal inflammatory pseudotumours: differential from nasopharyngeal carcinoma

The purpose of this study was to describe the MRI findings of inflammatory pseudotumours (IPTs) involving the nasopharynx and to differentiate IPTs from nasopharyngeal carcinoma (NPC). The medical records and imaging studies of 7 patients (6 men, 1 woman; age range, 32-71 years; mean age, 52.4+/-18 years) with IPT involving the nasopharynx were reviewed retrospectively. The MRI findings were compared with those of seven patients with advanced NPC with skull base invasion. All patients with IPT involving the nasopharynx presented with single or multiple cranial neuropathies; six reported pain; and four patients had a recent history of otitis media. Three were initially misdiagnosed as having NPC according to MRI findings, and all underwent nasopharyngeal biopsy to exclude malignancy. 7/7 (100%) patients received systemic corticosteroid treatment; 7/7 (100%) showed initial rapid resolution of clinical symptoms or radiographical findings; 3/7 (42.9%) had resolution of all signs and symptoms; 3/7 (42.9%) still have limited residual symptoms; and 1/7 (14.3%) suffered recurrence 3 years after remission. The characteristic MR findings of IPT include an infiltrative growth pattern, minimal to mild mass effect, hypointensity on T(2) weighted images, and moderate homogeneous enhancement after contrast administration. Intact nasopharyngeal mucosa, internal carotid artery encasement and narrowing, extensive pachymeningeal thickening and a relative paucity of associated neck lymphadenopathy are additional MR findings that favour the diagnosis of IPT rather than NPC. In conclusion, IPT involving the nasopharynx has characteristic MR findings which, together with clinical and laboratory presentations, are helpful in differentiating IPT from malignant tumours, especially NPC.

Dose Escalation of Three-dimensional Conformal Radiotherapy for Locally Recurrent Nasopharyngeal Carcinoma:Clinic II staging Prospective Randomized Study

Objective To investigate the feasibihty and efficacy of dose escalation using three-dimensional conformal radiotherapy(3D-CRT) boost technique for locally recurrent nasopharyngeal carcinoma(NPC) in a randomized study.Methods Thirty-six patients with locally recurrent NPC were treated between August 2004 and August 2007 at our institution.Patients were treated with exlemal-beam radiotherapy using small shaped fields to 50 Gy/25 fraetion/5 weeks,followed by a 3D-CRT boost to the gross tumor region.Patients were randomized to three boost dose levels:16 Gy(4 Gy×4 fractions) for Group Ⅰ:20;Gy(4 Gy×5 fractions) for Group Ⅱ;and 24 Gy(4 Gy×6 fractions) for Group Ⅲ.All boost doses were delivered as 3 fractions per week.Twelve patients were enrolled in each group.Median follow-up was 27 months (range 14～44 months).Results There was no significant difference among the three groups in acute and late toxicity.Overall 3-year survival rate was 65%,3-year local recurrence-free survival rate was 45%,and 3-year disrant metastasis rate was 10%.The local recurrence free survival was significantly hisher(72%) for the high-dose Group Ⅲ than that for Groups Ⅰ and Ⅱ.The 3-year distant metastases rates were no significant difference in Group Ⅰ,Ⅱ,Ⅲ respectively.There was no significant difference in the 3-year overall survival rate among the three groups.Univariate analysis revealed that skull base invasion and pathology were significant prognostic factors furoverall survival rate.Conclnsion Re-irradiation with hish-dose 3D-CRT boost results in high local control rate and acceptable toxicity in with recurrent NPC.Dose escalation to the boost volume to 74 Gy(54 Gy+24 Gy boost) results in improved recurrence-free survival to lower doses. Key words: 3D-CRT; Re-raditotherapy; Nasopharyngeal; Carcinoma; Measurement of incremental

Perineural Invasion in Aggressive Skin Carcinomas of the Head and Neck

Introduction: Perineural invasion is a well-recognized form of cancer dissemination. However, it has been reported only in few papers concerning cutaneous carcinomas (basal cell, BCC, and squamous cell, SCC). Moreover, the incidence is considered to be very low. Niazi and Lambert [Br J Plast Surg 1993;46:156–157] reported only 0.18% of perineural invasion among 3,355 BCCs. It is associated with high-risk subtypes, as morphea-like, as well as with an increased risk of local recurrence. No paper was found in the literature looking for perineural invasion in very aggressive skin cancers with skull base extension, with immunohistochemical analysis. Methods: This is a retrospective review, including 35 very advanced skin carcinomas with skull base invasion (24 BCCs and 11 SCCs, operated on at a single institution from 1982 to 2000). Representative slides were immunohistochemically evaluated with antiprotein S-100, in order to enhance nerve fibers and to detect perineural invasion. The results were compared to 34 controls with tumors with a good outcome, treated in the same time frame at the same Institution. Results: Twelve (50.0%) of the BCCs with skull base invasion had proven perineural invasion, as opposed to only 1 (4.6%) of the controls, and this difference was statistically significant (p < 0.001). Regarding SCCs, 7 aggressive tumors (63.6%) showed perineural invasion compared to only 1 (10.0%) of the controls, but this difference did not reach significance (p = 0.08), due to the small number of cases. Conclusions: In this series, it was demonstrated that immunohistochemically detected perineural invasion was very prevalent in advanced skin carcinomas. In addition, it was statistically associated with extremely aggressive BCCs with skull base invasion.

Nasopharyngeal carcinoma

Imaging plays an important role in the staging of nasopharyngeal carcinoma. Accurate staging is necessary, as the treatment is directly dependent on stage. Clinical examination provides information on mucosal involvement but is unable to determine the deep extension or the presence of skull base invasion or intracranial spread. The intent of this manuscript is to provide information of the specific imaging findings that will directly affect the stage and treatment of nasopharyngeal carcinoma as well as post-treatment complications.

Endoscopic Versus Traditional Craniofacial Resection for Patients with Sinonasal Tumors Involving the Anterior Skull Base

ObjectivesWith the advent of microdebriders and image guidance systems, endoscope-assisted surgery is now more widely used for the treatment of tumors involving the base of the skull. The aim of this study was to analyze the clinical features of tumors involving the anterior skull base and to evaluate the treatment outcomes according to the surgical approach, which included the traditional craniofacial resection (TCFR) and the endoscopic craniofacial resection with craniotomy (ECFR).MethodsForty-six patients who underwent craniofacial resection from 1989 through 2006 at Seoul National University Hospital and Seoul National University Bundang Hospital were included in this study. Demographics, histology, surgical management, surgical outcomes, complications, and morbidity were analyzed.ResultsThe number of malignant and benign lesions was 40 and 6 cases respectively. The most common diagnosis was olfactory neuroblastoma occurring in 41% of the cases followed by squamous cell carcinoma and malignant melanoma. Thirty-six patients underwent TCFR, while ECFR was performed with or without adjunctive chemotherapy or radiotherapy in 10 patients. The overall five-year survival rate for patients with malignant tumors of the anterior skull base was 47.4%. Out of 19 patients with olfactory neuroblastomas, 10 patients had TCFR and six among them died of their disease. Nine patients underwent ECFR, and none of them died of their disease. The ECFR group had lower morbidity and cosmetic deformity than did the TCFR group.ConclusionThe ECFR may be considered as an alternative option for the treatment of selected tumors with anterior skull base invasion. This approach offers the advantages of avoiding facial incisions with comparable treatment results.

Skull Base Invasion of Adenoid Cystic Carcinoma of the Lacrimal Gland : A Case Report

Although adenoid cystic carcinoma (ACC) of the lacrimal gland is a rarely encountered orbital tumor, it invades intracranially more frequently than carcinomas of other glands in the head and neck. A 52-year-old man underwent orbital exenteration and resection of intracranially extended tumor via a fronto-orbito-zygomatic approach in combination with a transfacial approach. Histopathologically, the tumor showed perineural, vascular, and lymphatic invasion. Additionally, he received radiotherapy (60 Gy) and adjuvant systemic cisplatin and 5-fluorouracil chemotherapy due to residual tumor in the orbit and systemic metastases (lung, ribs, and spines). He was free of progression and recurrence at 6 months after treatment. The authors report a case of skull base invasion by an ACC of the lacrimal gland to remind neurosurgeons planning intervention that this disease shows a tendency to invade intracranially.

Atypical Facial Access

To analyze the influence of the unique percentage of skin carcinomas with skull base invasion on the choice of the facial surgical approach. Multi-institutional retrospective analysis of the medical charts of all patients who had undergone oncological craniofacial operations from 1981 to 2005. Data were collected on demographic distribution, location of the primary tumor, histologic type, type of operation, reconstruction, complications, and outcome. Special attention was directed toward the choice of facial approach. Two major tertiary care centers. A total of 484 patients who had undergone major skull base operations. Frequency of atypical facial approaches. Impact on the need for more sophisticated reconstructions and on surgical morbidity. During this 25-year period, 484 patients underwent major skull base operations in the 2 centers; data concerning 467 cases were available for analysis. The median age of the patients was 52.8 years (range, 4-88 years), and the male-female ratio was 1.9:1.0. The initial location of the tumor was the craniofacial skin in 63.5% of cases, ethmoid in 10.8%, maxilla in 2.3%, orbit in 1.9%, and other origins, including endocranial, in 19.4%. The histologic type of the lesions was basal cell carcinoma in 42.0% of cases, squamous cell carcinoma in 29.5%, esthesioneuroblastoma in 5.3%, adenocarcinoma in 3.9%, adenoid cystic carcinoma in 2.8%, and other types in 16.5%. Owing to this high prevalence of advanced skin carcinomas, the most commonly employed facial approach was atypical, tailored to encompass all compromised skin and underlying tissues, in 55.5% of cases, followed by the Weber-Ferguson approach, with all its variations (eg, nasal swing) in 17.8%, lateral rhinotomy in 12.2%, facial translocation in 3.8%, and other facial techniques in 7.7%. No facial approach was required in 1.5% of cases. In most situations, head and neck surgeons chose an atypical surgical approach to properly resect all facial structures invaded by very advanced skin cancers.

Paranasal Sinus Malignancies with Skull Base Invasion

Purpose: Two thirds of malignant paranasal sinus neoplasms are diagnosed at stage T3 to T4. When skull base invasion is present prognosis is poor. The purpose of this work is to evaluate treatment results in 56 patients managed from 1997 to 2006 by an interdisciplinary team in a comprehensive cancer center.

Extensive Invasion of the Skull Base by Basal Cell Carcinoma of the Scalp

Extensive Invasion of the Skull Base by Basal Cell Carcinoma of the Scalp

Intratemporal Grafting of the Facial Nerve following Lateral Skull Base Tumor Resection

Intratemporal skull base tumors may invade the facial nerve in the horizontal (tympanic) or descending (vertical) segments, while parotid malignancies typically infiltrate the facial nerve at the stylomastoid foramen. This article will describe our results following intratemporal facial nerve grafting in 44 patients. This was a retrospective analysis of 44 patients requiring intratemporal facial nerve repair following lateral skull base tumor resection at our tertiary care, academic medical center. Tumor histology included 17 parotid cancers, 13 temporal bone malignancies, 9 glomus tumors, 3 facial neuromas, and 2 endolymphatic sac tumors. The greater auricular nerve was used in 25 patients and the sural nerve was used in 19 cases. Forty patients were available for facial function assessment at 2 years. Using the House-Brackmann (H-B) recovery scale, the breakdown of patients by facial function was as follows: Grade I, 0 patients; Grade II, 4 patients; Grade III, 29 patients; Grade IV, 4 patients; Grade V, 3 patients; and Grade VI, 0 patients. Facial paralysis may occur from intrinsic or external lateral skull base invasion of the facial nerve. Intratemporal interposition grafting resulted in favorable facial function (H-B II or III) in 33 of the 40 (82.5%) patients at the 2-year assessment.

Retrospective Review of 24 Cases of Head and Neck Cancer with Skull Base Invasion

Retrospective Review of 24 Cases of Head and Neck Cancer with Skull Base Invasion