Risk Factors for Progression in Vestibular Schwannomas After Incomplete Resection: A Single Center Retrospective Study

Background and Purpose: The risk factors for progression in vestibular schwannomas (VSs) after incomplete resection (IR) remain to be elucidated. The purpose of this study was to investigate the risk factors for progression in remnant VSs after surgery.Methods: From January 2009 to January 2018, 140 consecutive patients who underwent IR of VSs via suboccipital retrosigmoid approach in our institution were retrospectively analyzed. During follow-up, if progression was detected, the patient was classified into Progressive Group (PG); if the residual tumor was stable or shrank, the patient was classified into Stable Group (SG). Univariate analysis and multivariate analysis were used to evaluate the risk factors for progression after IR of VSs.Results: After a mean follow-up of 80.4 months (range, 24–134 months), 35 (25.0%) patients (PG) had a progression, and no progression was detected in 105 (75.0%) patients (SG). The average tumor size was 36.5 ± 8.9 mm in PG and 31.0 ± 9.8 mm in SG, respectively. The residual tumor volume was 304.6 ± 443.3 mm3 in PG and 75.9 ± 60.0 mm3 in SG, respectively. Univariate analysis showed that preoperative tumor size, residual tumor volume, and irregular internal auditory canal (IAC) expansion were significantly different between the two groups, whereas gender, age, cystic component, or Ki-67 labeling index (LI) did not differ significantly between the two groups. Multivariate analysis showed residual tumor volume was the independent risk factor for progression.Conclusions: VSs that underwent IR with larger preoperative size, greater residual tumor volume, or irregular IAC expansion may have a higher progression rate. Strict follow-up with shorter interval in these patients to detect early progression is necessary.

SURG-01. CYSTIC BRAIN METASTASES MANAGED WITH RESERVOIR PLACEMENT AND STEREOTACTIC RADIOSURGERY

BACKGROUND Stereotactic radiosurgery (SRS) has become a mainstay of treatment for patients with metastatic brain tumors. However, metastatic tumors with a large cystic component often exceed the size limit for safe and effective SRS. In such cases, surgical resection may not be the preferred first method of treatment, due to tumor location, patient co-morbidities, and patient preference. In such cases volume reduction by cyst aspiration followed by SRS may be a preferred option. OBJECTIVE To present the treatment of patients with cystic metastases using reservoir placement followed by SRS. METHODS Seven patients were treated with this method. We performed reservoir insertion for the aspiration of cystic component in each patient and followed that with outpatient SRS. RESULTS Mean overall volume reduction from this treatment method was 80% (range 46.5-94.9). Mean volume reduction from the cyst aspiration alone was 60.7% (range 3.5-90.9), and after SRS a further 71.6% (range 34.6-94.4), accounting for some cyst reaccumulation between the time of surgery and SRS. The interval between those two procedures were 24 days on average (range 11-58 days). Repeat reservoir aspiration was done a total of 10 times in 5 patients. CONCLUSION Cyst aspiration with reservoir placement followed by SRS is a good option for patients with large cystic brain metastases. The reservoir allows for repeat aspiration if needed. Catheter placement at the center of the cyst, and SRS within 2-3 weeks of surgery, can maximize the likelihood of a successful outcome.

Case Series: Cystic Brain Metastases Managed With Reservoir Placement and Stereotactic Radiosurgery

BACKGROUND Stereotactic radiosurgery (SRS) has become one of the mainstays of treatment for patients with metastatic brain tumors. However, metastatic tumors with a large cystic component often exceed the size limit for safe and effective SRS. In such cases, surgical resection may not be the preferred first method of treatment, due to tumor location, patient co-morbidities, and patient preference. In these patients, volume reduction by cyst aspiration (CA) followed by SRS may be a viable alternative treatment option. OBJECTIVE To present the treatment of patients with cystic metastases using reservoir placement followed by SRS. METHODS Nine patients were treated with this method. We performed reservoir insertion for the aspiration of cystic component in each patient and followed that with outpatient SRS. RESULTS Mean overall volume reduction from this treatment method was 78.5%. Mean volume reduction from the CA alone was 59.8%, and after SRS, a further 66.6%, accounting for some cyst reaccumulation between the time of surgery and SRS. Repeat reservoir aspiration was done a total of 10 times in 5 patients. Our study showed local tumor control in 7 of 9 patients (77.8%), while 2 patients required later surgical resection of their tumors. CONCLUSION CA with reservoir placement followed by SRS is a good option for patients with large cystic brain metastases. The reservoir allows for repeat aspiration if needed. Catheter placement at the center of the cyst, and SRS within 2 to 3 wk of surgery, can maximize the likelihood of a successful outcome.

Quantification of tumor response of cystic vestibular schwannoma to Gamma Knife radiosurgery by using artificial intelligence

OBJECTIVE Gamma Knife radiosurgery (GKRS) is a common treatment modality for vestibular schwannoma (VS). The ability to predict treatment response is important in patient counseling and decision-making. The authors developed an algorithm that can automatically segment and differentiate cystic and solid tumor components of VS. They also investigated associations between the quantified radiological features of each component and tumor response after GKRS. METHODS This is a retrospective study comprising 323 patients with VS treated with GKRS. After preprocessing and generation of pretreatment T2-weighted (T2W)/T1-weighted with contrast (T1WC) images, the authors segmented VSs into cystic and solid components by using fuzzy C-means clustering. Quantitative radiological features of the entire tumor and its cystic and solid components were extracted. Linear regression models were implemented to correlate clinical variables and radiological features with the specific growth rate (SGR) of VS after GKRS. RESULTS A multivariable linear regression model of radiological features of the entire tumor demonstrated that a higher tumor mean signal intensity (SI) on T2W/T1WC images (p < 0.001) was associated with a lower SGR after GKRS. Similarly, a multivariable linear regression model using radiological features of cystic and solid tumor components demonstrated that a higher solid component mean SI (p = 0.039) and a higher cystic component mean SI (p = 0.004) on T2W/T1WC images were associated with a lower SGR after GKRS. A larger cystic component proportion (p = 0.085) was associated with a trend toward a lower SGR after GKRS. CONCLUSIONS Radiological features of VSs on pretreatment MRI that were quantified using fuzzy C-means were associated with tumor response after GKRS. Tumors with a higher tumor mean SI, a higher solid component mean SI, and a higher cystic component mean SI on T2W/T1WC images were more likely to regress in volume after GKRS. Those with a larger cystic component proportion also trended toward regression after GKRS. Further refinement of the algorithm may allow direct prediction of tumor response.

Case Report: Giant Thyroid Cyst with Critical Airway Compresion

Thyroid nodules with cystic component are common and the vast majority of them do not cause symptoms. Their neck location, close to airway and vascular structures, makes them a potentially life-threating condition if they become bigger or suffer from an acute haemorrhage. In this case report we expose the case of a twenty-two year old man who went to our emergency service suffering from odynophagia and neck swelling. He was diagnosed with giant thyroid cyst and critical tracheal compression. Initially, in order to relieve symptoms, we carried out two ultrasound-guided aspirations; later, as final treatment, the patient underwent thyroid lobectomy. He progressed successfully without postoperative complications. In our experience, surgery is an effective and definitive treatment to consider in cases for big thyroid cyst in young patients.

Microsurgical resection of a giant cervico-medullary ependymoma: 2D-dimensional video

Background: Ependymoma is a slowly growing benign neoplasm that constitutes 3–9% of all neuroepithelial spinal cord tumors.[3,4] They rarely involve the cervicomedullary junction where they both compress the distal brainstem and upper cervical cord. Due to the critical contiguous structures, gross total resection of these lesions may result in significant morbidity/mortality.[1,2] Utilizing intraoperative neuromonitoring can help limit the risks of removing these lesions. Not when considering the risk/complications of partial versus total resection, the surgeon should keep in mind that they are benign slow growing tumors with relatively good long-term survivals following partial removals. This surgical video shows the surgical strategy and management of a giant cervicomedullary ependymoma performed in a 23-year-old female. Case Description: A 23-year-old female presented with cervical pain and quadriparesis of 1-year’s duration. The MR with/without gadolinium showed a large intradural, intramedullary cervical spinal cord tumor that severely expanded the spinal cord. It contained a significant cystic component, extending from the lower brain stem to the inferior aspect of C7. The lesion was hyperintense on T1 and T2 sequences and demonstrated minimal contrast enhancement. Surgery warranted a posterior cranio-cervical midline approach consisting of a suboccipital craniectomy with laminotomy. The pathological diagnosis was consistent with an ependymoma (WHO I). Fifteen days postoperatively, the patient was discharged with a minimal residual quadriparesis that largely resolved within 6 postoperative months. Three months later, the MRI confirmed complete tumor removal of the lesion. Notably, longer-term follow-up is warranted before complete excision can be confirmed. If there is a recurrence, repeat resection versus stereotactic radiosurgery may be warranted. Conclusion: This video highlights a safe and effective surgical technique for the resection of a giant cervicomedullary ependymoma.

Trousseau’s syndrome associated with an ovarian borderline tumour

A 71-year-old woman was admitted to our hospital because of sudden onset of weakness on the left side of her body. Her medical history was unremarkable, and on physical examination, hemiparesis and hyperreflexia on the left side were found. MRI of the brain showed multiple areas of restricted diffusion in both parietal lobes and in the cerebellum, consistent with embolic shower. Magnetic resonance angiography showed no abnormal findings. A contrast-enhanced CT scan revealed multiple pulmonary emboli. Abdominal MRI showed a 135 mm left ovarian tumour composed of a solid and a cystic component with liquid level formation. After a total hysterectomy and bilateral adnexectomy, the histopathology confirmed a seromucinous borderline tumour. Therefore, the patient was diagnosed with Trousseau’s syndrome associated with an ovarian seromucinous borderline tumour. To our knowledge, this is the first report mentioning a borderline ovarian tumour detected as Trousseau’s syndrome.

RADI-01. Cystic brain metastases managed with reservoir placement and stereotactic radiosurgery

Background Stereotactic radiosurgery (SRS) has become a mainstay of treatment for patients with metastatic brain tumors. However, metastatic tumors with a large cystic component often exceed the size limit for safe and effective SRS. In such cases, surgical resection may not be the preferred first method of treatment, due to tumor location, patient co-morbidities, and patient preference. In such cases volume reduction by cyst aspiration followed by SRS may be a preferred option. Methods Seven patients were treated with this method. We performed reservoir insertion for the aspiration of cystic component in each patient and followed that with outpatient SRS. Results Mean overall volume reduction from this treatment method was 80% (range 46.5–94.9). Mean volume reduction from the cyst aspiration alone was 60.7% (range 3.5–90.9), and after SRS a further 71.6% (range 34.6–94.4), accounting for some cyst reaccumulation between the time of surgery and SRS. The interval between those two procedures were 24 days on average (range 11–58 days). Repeat reservoir aspiration was done a total of 10 times in 5 patients. Conclusion Cyst aspiration with reservoir placement followed by SRS is a good option for patients with large cystic brain metastases. The reservoir allows for repeat aspiration if needed. Catheter placement at the center of the cyst, and SRS within 2–3 weeks of surgery, can maximize the likelihood of a successful outcome.

A SILENT CASE OF LARGE CYSTIC MENINGIOMA

Meningiomas are the most common extra-axial neoplasms. Meningiomas, in general may be benign or malignant. Cystic meningiomas are one of the subtypes of meningioma, mimicking an intra-axial lesion radiologically and clinically. The common clinical manifestations may include but not limit to headache, vomiting, seizures & focal neurological decits. The cystic component is an uncommon nding that makes it difcult to distinguish between a meningioma and a glial neoplasm radiologically. Here, we discuss a 54-year-old female patient who presented with subacute onset of transient memory disturbances and a sudden neurological deterioration who was found to have a cystic meningioma.

Heavily Calcified Gastrointestinal Stromal Tumour of Stomach: A Diagnostic Dilemma

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumour of gastrointestinal tract and the stomach being the most commonly involved organ. Focal calcification may be seen in GIST but prominent or heavy calcification is rare. Gastric mass with prominent calcification on imaging may create a diagnostic dilemma. We present a rare case of gastric GIST with heavy calcification in a 55 years old female presenting with abdominal lump. Computed tomography (CT) showed a large heterogenous juxta gastric mass with solid-cystic component with heavy calcification. She underwent laparotomy and en-bloc gastric sleeve resection with the mass. Microscopic examination showed tumour with spindle cell and calcification with mitotic index of 6/50 High power field. Immunoreactivity with Vimentin, CD34 and DOG 1 confirmed diagnosis of GIST. Dystrophic calcification of necrotic or degenerative tissue is thought to be cause of calcification in GIST. Very few cases of heavily calcified GIST have been reported in literature, our case is of interest because presence of solid cystic component and a huge size ~ 14 cm (longest diameter).