Lateral transcondylar approach for tumors at the anterior aspect of the craniovertebral junction.

BACKGROUND: Tumors at the craniovertebral junction are difficult to remove because of their location and complex anatomic relations. The lateral transcondylar approach is a versatile approach to this area and allows access to a variety of intra- and extradural tumors. The lateral transcondylar approach has been used for a series of chordomas in this location. OBJECTIVE: The nuances of this operation and its effectiveness in this group of patients are presented. METHODS: There were 29 chordomas (1991-2007) in this region treated by one of the authors (CS) that were retrospectively reviewed. The imaging studies and medical records were evaluated. The location and extent of the tumor were defined, and the postoperative images were studied to determine the degree of resection. RESULTS: There were 11 male and 18 female patients; their age range was 7 to 67 years. Headache and neck pain were the predominant presenting symptoms, and hypoglossal nerve palsy was the most common cranial nerve palsy. Twelve patients had previous surgery and 9 had previous radiation. Anterior midline and lateral approaches were used independently or in combination to treat these patients. Dural invasion was found in 27 patients requiring resection of the dura. Surgery was performed in 1 stage in 19 patients, and the tumor resection in the remaining patients was done in 2 stages. The lateral transcondylar approach was used in 19 patients. The occipital condyle was involved in all these patients. Radical tumor resection was achieved in 17 patients. Patients who had complete removal of the occipital condyle required occipitocervical fusion (20 patients) in the immediate postoperative period. CONCLUSION: The lateral transcondylar approach is an effective approach to chordomas in this region. Most of the tumors were large and extended into multiple anatomic compartments. The approach allowed resection of all the involved tissues, intra- and extracranial, and afforded excellent neurovascular control.

Clival chordomas: clinical management, results, and complications in 71 patients.

OBJECT: Chordomas are rare malignant neoplasms arising predominantly at the sacrum and skull base. They are uniformly lethal unless treated with aggressive resection and proton beam irradiation. The authors present results of the surgical management of a large number of patients with clivus chordomas. Factors that influence the surgeon's ability to achieve radical tumor resection are also evaluated. METHODS: Between 1991 and 2005, 71 patients with clivus chordomas underwent surgery. The average follow-up was 66 months (median 60 months, range 3-189 months). Sixty-five patients had complete records that were analyzed in the present report. Thirty-five percent of them had undergone surgery before being treated by the authors. They were evaluated with MR imaging and CT scanning and underwent surgery utilizing a variety of skull base techniques aimed at achieving radical excision. Many also underwent postoperative radiation, usually in the form of proton beam therapy. The patients were followed up with serial imaging at regular intervals as well as with neurological evaluation. RESULTS: Radical tumor resection was achieved in 58% of the group. The overall 5-year survival rate was 75%. Radical resection had a positive impact on survival. The ability to achieve radical resection was dependent on the preoperative tumor volume and the number of anatomical areas involved by the tumor. Cranial nerve impairment and CSF leakage were the most frequent postoperative complications. CONCLUSIONS: Radical excision is the ideal surgical goal in the treatment of clival chordomas and can be achieved with reasonable risks. Several different surgical approaches may be necessary to accomplish this.

Surgical management of chordomas of the cervical spine.

OBJECT: Chordomas of the cervical spine are rare tumors. Although en bloc resection has proven to be the ideal procedure in other areas, there is controversy regarding this approach in the cervical spine. The goal in this study was to determine whether piecemeal tumor resection was efficient in the management of chordomas that arise in this location. METHODS: The authors retrospectively reviewed all 74 cases of chordoma treated by their group. Seven patients with isolated cervical chordomas who were treated between October 1992 and January 2006 were identified. There were four male and three female patients, whose ages ranged from 6 to 61 years (mean 34.4 years). Follow-up duration ranged from 7 to 169 months (median 23 months). All cases were managed using a retrocarotid approach with mobilization of the vertebral artery. When the tumor could not be completely resected via the initial anterior approach, a subsequent posterior resection was performed. Tumor resection was intralesional in all cases, and gross-total tumor resection was achieved in six cases. One patient required a second resection 4 months later. In all cases, a posterior stabilization procedure was performed. Five patients underwent anterior fusion (three with fibular allograft and two with iliac crest), whereas two underwent occipitocervical fusion. In two patients with dedifferentiated chordoma metastasis developed, and one of them died 7 months later. The other patient with metastasis died suddenly at home 26 months postsurgery, presumably from aspiration. At the time of this submission, there were no signs of recurrence in five patients. CONCLUSIONS: The authors believe that, in most cases, en bloc resection of cervical chordoma is not feasible. This is due to the tendency of chordomas to involve multiple compartments at the time of diagnosis. In the authors' experience, intralesional radical resection remains an effective surgical approach to this disease entity.

N-cadherin expression in breast cancer: correlation with an aggressive histologic variant--invasive micropapillary carcinoma.

Upregulation of N-cadherin in epithelial tumor cells has been shown to contribute to the invasive/metastatic phenotype. It remains however to be determined whether N-cadherin is increased in human breast cancers with enhanced malignant potential. We examined a large number of invasive breast cancer specimens (n = 114) for N- and E-cadherin. These specimens compared invasive duct carcinomas (IDCs) of varying histologic grades with an aggressive subtype, invasive micropapillary carcinoma of the breast (MPAP), which has a high propensity for lymphatic invasion and lymph node metastasis. Staining scores for N- and E-cadherin were compared between non-MPAP and MPAP IDCs, and between the invasive and ductal carcinoma in situ (DCIS) of each IDC using statistical analysis. We found that N-cadherin was expressed in 76% of MPAP and 52% of non-MPAP carcinomas, and E-cadherin in 57% of MPAP and 36% of non-MPAP tumors. More MPAP (25%) compared to non-MPAP (5%) tumors expressed both cadherins. Of the two cadherins, N-cadherin was significantly associated with MPAP tumors (p = 0.033) compared to E-cad (p = 0.171). Moreover, in the majority of tumors that were positive for N-cadherin, the staining scores were increased in the IDC relative to intraductal components, and this effect was more dramatic in the MPAP carcinomas. This difference for N-cadherin was greater than the corresponding difference for E-cadherin in the MPAP group (p = 0.005), whereas such changes were not significant in the non-MPAP group (p = 0.10). Thus, N-cadherin is associated with tumor aggressiveness and metastatic potential and may contribute to tumor progression.

Cadherins and catenins in clival chordomas: correlation of expression with tumor aggressiveness.

The local invasiveness and occasional rapid growth of chordomas, despite optimal treatment, highlight the need to develop ways to predict their biologic behavior. Alterations in adhesion proteins have been shown to participate in proliferation, invasiveness, and metastasis in epithelial tumors. We therefore analyzed the expression of E-cadherin, N-cadherin, as well as their cytosolic binding proteins alpha-catenin, beta-catenin, and gamma-catenin, in 51 paraffin archived and 17 cryopreserved chordoma specimens. In the majority of chordomas, E-cadherin and N-cadherin expression was inversely correlated, whereas beta-catenin and gamma-catenin expression was directly correlated. By multivariate analysis, N-cadherin up-regulation correlated with a diminished recurrence-free survival, and E-cadherin down-regulation strongly correlated with increased probabilities of death as determined by the Kaplan-Meier log-rank test. There was a 3.28-fold increased probability of having a tumor recurrence and a 10.98-fold increased probability of dying when, respectively, N-cadherin was up-regulated and E-cadherin down-regulated. These results suggest that changes in the relative expression of the cadherin-catenin complex reflect chordoma aggressiveness; and that decreased expression of E-cadherin and increased expression of N-cadherin may underlie the transition from a less to a more aggressive tumor phenotype.