Nuances in the treatment of malignant tumors of the clival and petroclival region

Abstract

Introduction Malignancies of the clivus and petroclival region are mainly chordomas and chondrosarcomas. Although a spectrum of malignancies may present in this area, a finite group of commonly encountered malignant pathologies will be the focus of this review, as they are recognized to be formidable pathologies due to adjacent critical neurovascular structures and challenging surgical approaches. Objectives The objective is to review the literature regarding medical and surgical management of malignant tumors of the clival and petroclival region with a focus on clinical presentation, diagnostic identification, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to the skull base. Data Synthesis A literature review was conducted, searching for basic science and clinical evidence from PubMed, Medline, and the Cochrane Database. The selection criteria encompassed original articles including data from both basic science and clinical literature, case series, case reports, and review articles on the etiology, diagnosis, treatment, and management of skull base malignancies in the clival and petroclival region. Conclusions The management of petroclival malignancies requires a multidisciplinary team to deliver the most complete surgical resection, with minimal morbidity, followed by appropriate adjuvant therapy. We advocate the combination of endoscopic and open approaches (traditional or minimally invasive) as required by the particular tumor followed by radiation therapy to optimize oncologic outcomes.

Keywords: chondrosarcoma; chordoma; clival; craniotomy; endoscopic endonasal; malignancy; petroclival; plasmacytoma; skull base.

Fig. 1

Clival chordoma in a 21-year-old man, who presented with a large compressive midline lesion and diplopia, dysphagia, and left upper extremity weakness. (Left) Sagittal computed tomography and arterial angiography scan demonstrating a large expansile lytic mass in the clivus with compression of important surrounding neurovascular structures and brainstem. (Middle) Magnetic resonance imaging (MRI) of postcontrast T1-weighted sequence axial scans of a heterogeneously enhancing chordoma with significant mass effect. (Right) Postoperative MRI postcontrast T1-weighted scans showing extensive resection and decompression of around brainstem.

Fig. 2

Petroclival midline lytic mass incidentally discovered on computed tomography scan (CT) after a 38-year-old man was involved in a motor vehicle accident (top left). Follow-up scans with magnetic resonance imaging (MRI) revealed interval growth of the midline lesion and an enhancing pattern with a midline location consistent with chordoma (top middle). T2-weighted sequences revealed a hyperintense mass also consistent with chordoma (top right). Aggressive gross total resection evidenced by postoperative CT and MRI scan (bottom left, middle, and right) was followed by proton beam therapy.

Fig. 3

Progressive recurrence of a clival chordoma that had been resected and treated with proton beam therapy. From left to right progressive recurrence over a 3-year period of local spread down the cervical spine inevitably leading to spinal cord compression, paralysis, and eventually death.

Fig. 4

Right-sided petroclival chondrosarcoma in a 47-year-old woman who presented with diplopia, headaches, and nausea/vomiting. Magnetic resonance imaging (MRI) revealed an enhancing mass at the right petrous apex with involvement of the clivus and significant temporal brain compression. (Top left) coronal MRI T1-weighted postcontrast scans demonstrating temporal lobe compression. (Top middle) axial MRI T1-weighted postcontrast scans. (Top right) T2-weighted sequence scans demonstrating hyperintense lateral paraclival mass with posterior fossa compression. (Bottom) Postoperative MRI scans in matching order as the top row. Gross total resection was achieved via an endoscopic transsphenoidal surgical resection of the lesion, which had followed a subtemporal craniotomy for debulking performed previously elsewhere.

Fig. 5

A 41-year-old man, who had undergone surgery and proton beam radiotherapy for a chondrosarcoma of the clivus in his early 20s. He presented ∼20 years later with new symptoms and worsening of his double vision, pain, and a new expansile clival mass. Biopsy of the lesion revealed a spindle cell sarcoma confirmed to be a malignant meningioma (World Health Organization grade III) that was refractory to chemotherapy. An endoscopic endonasal approach for gross total resection was achieved. (Top left and right) Sagittal and axial computed tomography and arterial angiography scans demonstrating an expansile clival with mass effect on the brain stem. (Middle left and right) Preoperative magnetic resonance imaging (MRI) T1-weighted postcontrast scans demonstrating clival meningioma. (Bottom left and right) Postoperative MRI T1-weighted postcontrast scans demonstrating resection of clival meningioma and brainstem decompression.

Fig. 6

Magnetic resonance imaging (MRI) and gross pathologic specimen from a patient with a malignant peripheral nerve sheath tumor. (Top left and right) Preoperative MRI T1-weighted postcontrast scans demonstrating a large extensive left-sided malignant peripheral nerve sheath tumor of the trigeminal nerve seen within the petrous bone and extending out into the parotid gland (not seen). (Middle left and right) Postoperative MRI T1-weighted postcontrast scans. (Bottom) Resection of gross specimen pictured as seen with histologic examination revealing a malignancy consistent with a malignant schwannoma.

Fig. 7

A 51-year-old man presented initially with some right-sided hearing symptoms, and investigation showed the presence of a large destructive lesion involving the right petrous apex and internal auditory canal with extension anterior to the skull base, the right internal auditory canal, on computed tomography scans (left). Magnetic resonance postcontrast scans (right) confirm an enhancing lesion in the petrous bone with intracranial extension into the right cerebellopontine angle cistern with extension around the internal carotid artery and high cervical area. Days later in the middle of his medical workup that was largely negative for multiple myeloma, he presented with a seventh cranial nerve palsy. An endoscopic endonasal approach confirmed the pathology was consistent with a plasmacytoma.

Fig. 8

A 61-year-old patient presented with cranial nerve VI palsy and a midline clival mass, possibly chordoma. (Top left to right) Preoperative magnetic resonance imaging (MRI) T1-weighted postcontrast scans demonstrating a focal midline moderately enhancing clival mass. T2-weighted sequences revealed a hypointense mass atypical for chordoma (top row, fourth panel on the right). Endoscopic endonasal approach and resection of mass revealed a metastatic thyroid carcinoma. (Bottom left and right) Postoperative MRI T1-weighted postcontrast scans. Bottom row also includes gross specimen pictured as seen with histologic examination revealing a malignancy consistent with thyroid carcinoma.

Fig. 9

Our surgical setup includes preparations for endoscopic endonasal approaches (EEAs), open craniotomies, and combined approaches to pathologies of the skull base. (Top left and middle) Our endoscopic endonasal approach surgical suite with two operating teams, neurosurgery and otolaryngology, positioned on either side of the patient with dual video monitors in their field of view. (Middle) A screen shot of an operator's field of view on the monitor during dissection. (Top right) An open craniotomy after the completion of a first-stage endoscopic endonasal approach. (Bottom) A skull base chordoma in a 47-year-old woman with lateral extension that required a two-stage procedure. (Left) Preoperative magnetic resonance imaging (MRI) T1-weighted postcontrast scans demonstrating the large chordoma with lateral extension. (Middle) Postoperative MRI after an EEA with residual lateral tumor that could not be reached. (Right) Postoperative MRI after open pterional craniotomy and gross total resection of enhancing remnant tumor.