Intraventricular Tumor Resection

This is a case of a 49-year-old patient who presented with persistent headaches with no focal neurologic deficit. An MRI was performed which revealed an intraventricular tumor. The lesion was seen entering the third ventricle and potentially compressing both foramina of Monro. This was further confirmed through coronal reconstruction. The proposed method for tumor removal is an interhemispheric, transcallosal approach.

Central nervous system (CNS) tumors, such as this, are uncommon neoplasms that often present with symptoms like headache, nausea, vomiting, ataxia, vertigo, and papilledema. There is also the possibility of hydrocephalus, as the tumor can obstruct cerebrospinal fluid (CSF) outflow, and the development of seizures. These tumors often grow slowly and can be managed with surgical resection, chemotherapy, and/or stereotactic radiosurgery. For intraventricular tumor resection, the surgical approach can vary based on the tumor location, experience, and preference of the surgeon. Further details of the procedure and patient outcomes will be discussed in the subsequent sections of this article.

Ventricle tumor; cerebral neoplasm; cerebroventricular ventricular neoplasm; brain.

Intraventricular tumors of the central nervous system (CNS) can either arise in the anterior fossa or the posterior fossa, with the former being more common in adults. Of these tumors in the anterior fossa, the oncotypes are most commonly subependymomas, central neurocytomas, intraventricular meningiomas, and metastases.¹ Brain tumors originating from the posterior fossa are commonly ependymomas, subependymal giant cell astrocytomas, and choroid plexus papillomas.¹ Brain tumors of any type accounted for 1.4% of all new cases of cancer and 2.4% of all cancer deaths in 2014.² Due to their precarious location, intraventricular tumors have been an operative challenge, historically. Fortunately, advancements in neurosurgery have circumvented much of the inherent risk of a transcortical approach, with microsurgery among the most important developments for patients with intraventricular tumors. Ionizing radiation is a well-known risk factor for CNS tumors. The common risk factors of cancers, tobacco, alcohol, and/or diet, have not yet been explicitly implicated in the pathogenesis of CNS tumors.³ In this case, an interhemispheric transcallosal approach was utilized to resect a tumor in the lateral ventricle of a 49-year-old patient with symptoms of persistent headaches.

In this case, the patient presented with persistent headaches. This symptom is one of the most common in patients with intracranial tumors, which can vary based on the size and location of the tumor. While the patient did not exhibit other common symptoms such as seizures, it’s important to note that these symptoms can occur in other cases.²

Intracranial tumors, depending on their location, can obstruct the cerebrospinal fluid (CSF) tracts, potentially leading to the development of hydrocephalus and causing papilledema, which would be observable on a fundoscopic exam. However, this patient did not present with these symptoms.

It’s also worth noting that intraventricular tumors are often asymptomatic and found incidentally.⁴ Despite the absence of these symptoms in our patient, the diagnosis was confirmed through imaging, which is the most reliable method for detecting such masses. This highlights the importance of thorough examination and diagnostic testing in the management of intracranial tumors. Further investigation and management of this case will be discussed in the subsequent sections of this report.

The most specific imaging modality, gadolinium-enhanced MRI, was used in this case.² There is no specific radiological feature to delineate between tumors of metastatic or primary origin. There is a role for chest and abdomen computed tomography if metastasis is suspected; however, in the absence of clinical features pointing to a specific origin, determining the primary location of an extracranial tumor can be difficult.

Intraventricular and intracranial tumors that are left untreated not only lead to a worsening of symptoms but may also cause complications such as cerebral edema and volumetric growth of the tumor. While intracranial tumors are typically slow-growing, there is a possibility for acute intracranial or intratumoral hemorrhage or acute obstructive hydrocephalus, which would indicate a surgical emergency.⁵

Management of intracranial tumors is largely surgical. In certain circumstances, chemotherapy or radiotherapy can be utilized to optimize surgical candidates for total surgical resection. The surgical approach varies on the ventricle that the tumor is in.³

The chemotherapy regimen of choice is ifosfamide, carboplatin, etoposide (ICE).⁶ Chemotherapy can be used to stall the progression of the disease for patients’ first surgery or a second-look surgery, and pretreatment with chemotherapy has been shown to have high rates of near-total resection. Of note, the use of chemotherapy is associated with significant neurocognitive impairment.⁶

Stereotactic radiosurgery (SRS) and whole-brain radiotherapy (WBRT) are also options that can be used in conjunction with surgery or as a substitute for surgery. Outcomes of SRS and surgical resection are similar, with SRS being reserved for patients with more advanced disease with multiple locations.⁷

The goal of treatment was to remove the tumor in order to relieve symptoms, determine the oncotype of the tumor and other complications that may impact the patient’s quality of life.

Patients should always be counseled on the possible side effects of each treatment option. With advancements in microsurgery, the inherent risk of intracranial operations has been notably reduced and remains the best option for therapy.

In this case, a successful transcallosal approach was used to remove an intraventricular tumor lying in the lateral ventricles of a 49-year-old patient who presented with symptoms of an intracranial mass.

The surgical procedure began with a craniotomy, which was performed 2/3 ahead and 1/3 behind the coronal suture. However, it’s worth noting that some authors suggest that for the best avascular approach, the midpoint of the craniotomy could be aimed at 2.5 cm ahead of the coronal suture.⁹

Following the craniotomy, the dura was opened and the interhemispheric space was prepared. Both pericallosal arteries and the corpus callosum were then prepared. The next step involved opening the corpus callosum, removing the CSF, and identifying the intraventricular tumor.

The final stage of the procedure was the removal of the tumor. In this case, due to the small size of the callosotomy, the tumor was removed in a piecemeal fashion. However, it should be emphasized that en bloc removal is generally the preferred option when conditions permit. This comprehensive approach ensured the successful execution of the procedure, with further details to be discussed in the subsequent sections of this report.

Surgical management is the most effective treatment for intraventricular tumors if there are clinical manifestations and can be performed via three different approaches: open ventriculostomy, neuroendoscopical, and transcallosal.^3,8 Choice of the surgical technique depends on several factors such as the size and location of tumor. Neuroendoscopy and transcallosal approaches are associated with positive outcomes such as shorter operative time, decreased blood loss, shorter hospitalization, reduced postoperative pain, and earlier return to normal activity. Alternatively, neuroendoscopy is becoming a more popular technique and is also associated with positive outcomes similar to traditional approaches.⁸ However, these approaches are not indicated when patients present with larger tumors, due to their increased risk of complications. Neuroendoscopic removal of the tumor can be especially challenging, causing excessive bleeding and thus prolonged operative time.⁸

SRS is an alternative procedure that has several indications: multiple intracranial tumors, very large intracranial tumors, restricted operability, microscopic disease remaining after primary resection.⁷ SRS remains a good option for metastatic disease in the brain. However, the risk-to-benefit ratio for radiation therapy for benign tumors has not been established. WBRT has a broad toxicity profile and has fallen out of favor as a result of SRS therapy becoming more accessible.⁷

In some circumstances, the ICE chemotherapy regimen is used in patients in addition to surgical intervention. ICE therapy is often used for lymphoma; however, it is also indicated in the treatment of choroid plexus carcinoma. In a study published by Lafay-Cousin et al., ICE therapy has been shown to lead to a cessation in tumor growth; however, this chemotherapy also comes with a plethora of side effects including nephrotoxicity, neurotoxicity, and neutropenia.⁶ Despite the evidence that pretreating with ICE improves the possibility of total or near-total resection, the risk of neurotoxicity is not to be understated. A plurality of patients treated with ICE chemotherapy displayed significant neurocognitive or sensory derangement after therapy. The risk-to-benefit ratio of nonoperative management of intraventricular tumors is low. At this time, further research is needed to determine the role, and in which combination with surgery, that these therapies play in the treatment of intraventricular tumors.⁶

Standard neurosurgical equipment.

Nothing to disclose.

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.