Chondrosarcoma of the petrous apex. Dilemmas in diagnosis and treatment

Racial disparity in recommendation for surgical resection of skull base chondrosarcomas: A Surveillance, Epidemiology, and End Results (SEER) analysis

INTRODUCTION

There is increased appreciation of racial disparities in the delivery of neurosurgical care. Here, we explore whether race influences surgical recommendations in the management of skull base chondrosarcomas.

METHODS

We identified 493 patients with skull base chondrosarcoma using the Surveillance, Epidemiology, and End Results (SEER) registry (November 2017 submission). Regression analyses were performed to identify demographic variables associated with recommendation against surgery. Univariate and multivariate cox proportional hazards models were used for survival analysis.

RESULTS

In a univariate analysis, we found that the African-American race was associated with an increased likelihood of surgeon recommendation against surgery (OR = 4.416, 95% CI = 1.893-10.302, p = 0.001). This association remained robust in the multivariate model that controlled for other covariates, including age of diagnosis (OR = 5.091, 95% CI = 2.127-12.187, p < 0.001). For patients who received a recommendation against surgery, the likelihood of dying from non-chondrosarcoma causes was comparable between Caucasian and African-American patients, suggesting that the prevalence and severity of medical conditions that increase the risk of death were comparable between these cohorts (HR = 0.466, 95% CI = 0.057-3.802, p = 0.475). The likelihood of dying from chondrosarcoma was comparable between Caucasian and African-American patients who underwent surgery (HR = 0.982, 95% CI = 0.353-2.732, p = 0.973), suggesting absence of race-specific surgical benefits.

CONCLUSION

We identified a racial disparity against African-Americans in recommendations for surgical resection of skull base chondrosarcomas.

Endoscope-assisted contralateral transmaxillary approach to the clivus and the hypoglossal canal: technical case report

Clival lesions are still considered surgically complex due to their anatomical location. Critical structures, such as the internal carotid arteries (ICAs), cavernous sinuses, cranial nerves, and brainstem, may be encased within the lesion. Although advances in endoscopic endonasal approaches have provided new routes to these lesions, exposure and resection of clival tumors through the endonasal route remain a technical challenge. Here, the authors report a left-sided endoscopic transmaxillary approach to access the right aspect of the clivus and the hypoglossal canal.A 35-year-old woman presented with progressive right 6th cranial nerve palsy. MRI revealed a contrast-enhancing right petroclival chondrosarcoma that involved Meckel's cave and extended into the right hypoglossal canal. An endoscopic-contralateral-transmaxillary approach through a left sublabial incision was used to access the right petroclival region and right hypoglossal canal. A left maxillary osteoplastic flap was elevated to expose the left maxillary sinus. This was followed by a left medial maxillectomy, gaining access to the left posterior nasal cavity. The posterior third of the left inferior turbinate and nasal septum were removed to access the right side of the petroclival region. Near-total resection was achieved without any vascular or neurological complications. A thin shell of residual tumor was left behind due to involvement of vital structures, such as the ICA, and further treated with proton-beam radiotherapy.The endoscopic-contralateral-transmaxillary approach provides a direct surgical corridor and good lateral visualization of the skull base vasculature. This approach allows wide maneuverability around the ICA and hypoglossal canal, which, in this case, allowed maximal tumor resection with full preservation of neurological function.

Endoscopic transorbital route to the petrous apex: a feasibility anatomic study

BACKGROUND

While the subtemporal approach represents the surgical module milestone designed to reach the petrous apex, a novel ventral route, which is the superior eyelid endoscopic transorbital approach, has been proposed to access the skull base. Accordingly, we aimed to evaluate the feasibility of this route to the petrous apex, providing a qualitative and quantitative analysis of this relatively novel pathway.

METHODS

Five human cadaveric heads were dissected at the Laboratory of Surgical NeuroAnatomy of the University of Barcelona. After proper dissection planning, anterior petrosectomy via the endoscopic transorbital route was performed. Specific quantitative analysis, as well as dedicated three-dimensional reconstruction, was done.

RESULTS

Using the endoscopic transorbital approach, it was possible to reach the petrous apex with an average volume bone removal of 1.33 ± 0.21 cm³. Three main intradural spaces were exposed: cerebellopontine angle, middle tentorial incisura, and ventral brainstem. The first one was bounded by the origin of the trigeminal nerve medially and the facial and vestibulocochlear nerves laterally, the second extended from the origin of the oculomotor nerve to the entrance of the trochlear nerve into the tentorium free edge while the ventral brainstem area was hardly accessible through the straight, ventral endoscopic transorbital trajectory.

CONCLUSION

This is the first qualitative and quantitative anatomic study concerning details of the lateral aspect of the incisura and ventrolateral posterior fossa reached via the transorbital window. This manuscript is intended as a feasibility anatomic study, and further clinical contributions are mandatory to confirm the effectiveness of this approach, defining its possible role in the neurosurgical armamentarium.

Skull base chondrosarcomas: surgical treatment and results

OBJECTIVES

We describe our experience in the management of patients with skull base chondrosarcoma, an uncommon neoplasm of the skull base.

METHODS

Thirteen cases of surgically treated skull base chondrosarcomas were identified. The patients' follow-ups ranged from 7 to 86 months (mean, 47 months).

RESULTS

The most common tumor locations were the jugular foramen (5 cases), the petrous apex (3 cases), and the petroclival region (3 cases). An infratemporal fossa type A approach was performed in 2 cases, and 2 patients underwent an infratemporal fossa type B approach. Two patients underwent a transotic approach, 1 patient underwent a petro-occipital transsigmoid approach, and a petro-occipital transsigmoid approach combined with a transotic approach was chosen in 1 case. One patient underwent an infratemporal fossa type C approach combined with a transotic approach, and 2 patients underwent an infratemporal fossa type B approach combined with a transotic approach. One patient underwent an infratemporal fossa type B approach combined with a transzygomatic approach, and the last patient underwent a transmastoid approach. Gross total tumor removal was achieved in all patients. Postoperative radiotherapy was performed in 7 cases. The most common complications were lower cranial nerve deficits. Two patients experienced recurrences, 36 months and 6 years after surgical removal.

CONCLUSIONS

We believe that the primary treatment for chondrosarcomas of the skull base is gross total surgical resection. We usually do not recommend radiotherapy as the primary treatment for patients with skull base chondrosarcomas; however, radiotherapy may be considered as an alternative primary treatment in selected cases in which there are serious medical contraindications to surgery, as well as in elderly patients. We reserve postoperative radiotherapy for patients with histologically aggressive tumors (grade II or III), as well as for cases of subtotal resection or recurrent tumors.

Skull base chondrosarcoma: evidence-based treatment paradigms

Chondrosarcomas are indolent but invasive chondroid malignancies that can form in the skull base. Standard management of chondrosarcoma involves surgical resection and adjuvant radiation therapy. This review evaluates evidence from the literature to assess the importance of the surgical approach and extent of resection on outcomes for patients with skull base chondrosarcoma. Also evaluated is the ability of the multiple modalities of radiation therapy, such as conventional fractionated radiotherapy, proton beam, and stereotactic radiosurgery, to control tumor growth. Finally, emerging therapies for the treatment of skull-base chondrosarcoma are discussed.

Cranial chondrosarcoma and recurrence

The literature regarding recurrences in patients with cranial chondrosarcoma is limited to small series performed at single institutions, raising the question if these data precisely reflect the true recurrence of this tumor for guiding the clinician in the management of these patients. An extensive systematic review of the English literature was performed. The patients were stratified according to treatment modality, treatment history, histological subtype, and histological grade, and the recurrence rates were analyzed. A total of 560 patients treated for cranial chondrosarcoma were included. Five-year recurrence rate among all patients was 22% with median follow-up of 60 months and median disease-free interval of 16 months. Tumor recurrence was more common in patients who only received surgery or had mesenchymal subtype tumors. Our systematic review closely reflects the actuarial recurrence rate and provides predictive factors in the recurrence of cranial chondrosarcoma.

A systematic review of intracranial chondrosarcoma and survival

Most data regarding survival in patients with chondrosarcoma are limited to case studies and small series performed at single institutions. A systematic review was performed to study the relationship between potential prognostic factors and survival. The survival rates were analyzed according to modality of treatment, treatment history, histological subtype, and histological grade. A total of 560 patients with intracranial chondrosarcoma were analyzed. Median follow-up time was 60 months. The 5-year mortality among all patients was 11.5% with median survival of 24 months. Mortality at 5 years was significantly greater for patients with tumors of higher grade, or of the mesenchymal subtype, or who had received surgical resection alone. The results of our systematic review provide useful data in predicting survival among intracranial chondrosarcoma patients.

Unusual presentation of petro-clival chondrosarcoma: short report

Skull base chondrosarcoma is a rare neoplasm. Our patient presented with acute onset of diplopia along with symptoms of lower cranial nerve palsies in 1997. She showed complete resolution of symptoms following a short course of antibiotics and remained quiescent for three years. However, remission of symptoms in chondrosarcoma is unusual. An unusual case of a patient with petroclival low grade chondrosarcoma, who presented with relapse of symptoms after three years and was treated with surgery and radiotherapy, is presented.

Chondrosarcomas of the skull base and temporal bone

OBJECTIVE

To evaluate the clinical presentation and outcomes of treatment for patients with chondrosarcomas involving the skull base and temporal bone.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary medical centre.

PATIENTS

Cases of histologically confirmed chondrosarcoma involving the skull base and temporal bones.

INTERVENTION

Surgery.

MAIN OUTCOME MEASURES

Demographic features of presenting patients; presenting symptoms and signs; surgical approach employed; use of post-operative radiation therapy; histological grade of tumour; and interval of post-operative follow up.

RESULTS

Twelve patients were identified with chondrosarcomas involving the skull base, with post-operative follow up ranging from three to 33 years. The average age at presentation was 42 years. The most common presenting symptoms were diplopia, decreased visual acuity and headaches. Five of the 12 patients required multiple surgical procedures.

CONCLUSIONS

Patients with chondrosarcoma involving the skull base and temporal bone may present in a variety of ways. Surgical resection, even subtotal, in combination with radiation therapy, can often provide good tumour control over many years for these rare tumours.

The challenges of revision skull base surgery

Because the skull base is an anatomically complex structure, skull base tumors can hide easily in the crevices that interconnect the intra- and extracranial spaces and intermingle with important neurovascular structures. Often, total surgical resection of these tumors is not possible, and even with postoperative adjuvant radiotherapy, some recurrences after treatment are inevitable. Early detection of recurrent skull base tumors requires clinical vigilance and periodic imaging studies. The management of recurrent skull base tumors presents many challenges beyond those associated with primary procedures. A multidisciplinary setting that includes modern microsurgery and stereotactic radiation therapy provides patients with optimal care.

[Skull base chondrosarcoma. An interdisciplinary challenge]

BACKGROUND

Chondrosarcoma is a rare differential diagnosis of malignant tumours of the skull base. The prognosis was rated as unfavourable in articles for many years. It has, however, improved considerably in recent years. The objective of this study was to evaluate and current, new optimised treatment strategies.

PATIENTS AND METHODS

We retrospectively analysed the case histories and course of four patients whom we treated for chondrosarcoma of the skull base over the past 5 years at the Freiburg Skull Base Centre.

RESULTS

Because of initially mild symptoms, the patients first came for examination at an advanced stage of the tumour. All patients underwent surgery, whereby an R0-resection was barely or only questionably present. Three patients underwent radiation therapy postoperatively. All patients are currently tumour free.

CONCLUSIONS

Surgical treatment with curative intent is basically the therapy of choice. Due to the usually large size of the tumour and its close relationship to relevant structures, complete resection is, however, not always possible despite advances in surgical procedures. Taking the possibility of modern adjuvant radiotherapeutic procedures into account, an incomplete, function-preserving resection is preferred to a radical and mutilating resection.

Chondrosarcoma of the skull base

OBJECTIVES

Sarcomas of the skull base are challenging, potentially lethal tumors. Prognosis is considered poor. The present report reviews treatment options and presents a case of treatment with en bloc resection of the temporal bone and adjacent skull base.

STUDY DESIGN

Single case report and literature review.

RESULTS

Extensive skull base resection for chondrosarcoma can be performed successfully and may be curative.

CONCLUSION

There is a role for en bloc resection of large areas of the skull base for treatment of chondrosarcoma. It appears that treatment combining surgery and radiation therapy is most likely to be effective.