Management of tumor bed cysts after chemotherapeutic wafer implantation. Report of four cases

The clinical significance of radiological changes associated with gliadel implantation in patients with recurrent high grade glioma

Gliadel occasionally induces edema following its implantation. We aimed to correlate such post-surgical radiological changes to its efficacy and subsequent survival. Fifty-six patients with recurrent high grade glioma were treated between 2005 and 2016 with Gliadel implantation. Volumetric measurements of MRI features, including FLAIR abnormalities, tumor bulk (volume of gadolinium enhancement on T1) and resection cavity volumes over time were conducted. To assess dynamics over time, linear regression trendlines for each of these were calculated and examined to correlate with survival. Median follow-up after resection was 21.5 months. Median survival post-Gliadel implantation and overall survival since diagnosis were 12 months and 22 months, respectively. A subgroup of patients (n = 6) with a transient increase in FLAIR changes volume over time survived significantly longer post-Gliadel compared to those who did not demonstrate such change (36 vs 12 months, p = .03). Positive trends, representing overall growth in volume over time, of tumor bulk and resection cavity predicted survival in multivariate analyses (hazard ratios 7.9 and 84, p = .003 and .002, respectively). Increase in tumor bulk and resection cavity over time were associated with decreased survival, while transient FLAIR increase was a favorable prognostic factor. This may represent a transient inflammatory process in the tumor, possibly stemming from a presumed immune-mediated anti-tumor response.

Discriminating surgical bed cysts from bacterial brain abscesses after Carmustine wafer implantation in newly diagnosed IDH-wildtype glioblastomas

Carmustine wafers can be implanted in the surgical bed of high-grade gliomas, which can induce surgical bed cyst formation, leading to clinically relevant mass effect. An observational retrospective monocentric study was conducted including 122 consecutive adult patients with a newly diagnosed supratentorial glioblastoma who underwent a surgical resection with Carmustine wafer implantation as first line treatment (2005-2018). Twenty-two patients (18.0%) developed a postoperative contrast-enhancing cyst within the surgical bed: 16 surgical bed cysts and six bacterial abscesses. All patients with a surgical bed cyst were managed conservatively, all resolved on imaging follow-up, and no patient stopped the radiochemotherapy. Independent risk factors of formation of a postoperative surgical bed cyst were age ≥ 60 years (p = 0.019), number of Carmustine wafers implanted ≥ 8 (p = 0.040), and partial resection (p = 0.025). Compared to surgical bed cysts, the occurrence of a postoperative bacterial abscess requiring surgical management was associated more frequently with a shorter time to diagnosis from surgery (p = 0.009), new neurological deficit (p < 0.001), fever (p < 0.001), residual air in the cyst (p = 0.018), a cyst diameter greater than that of the initial tumor (p = 0.027), and increased mass effect and brain edema compared to early postoperative MRI (p = 0.024). Contrast enhancement (p = 0.473) and diffusion signal abnormalities (p = 0.471) did not differ between postoperative bacterial abscesses and surgical bed cysts. Clinical and imaging findings help discriminate between surgical bed cysts and bacterial abscesses following Carmustine wafer implantation. Surgical bed cysts can be managed conservatively. Individual risk factors will help tailor their steroid therapy and imaging follow-up.

Space-Occupying Tumor Bed Cysts as a Complication of Modern Treatment for High-Grade Glioma

BACKGROUND

The management of high-grade glioma (HGG) has been affected by recent landmark trials and is now more proactive. More aggressive treatment leads to hospitalization due to side effects, however. Space-occupying tumor bed cysts have been described, but not systematically assessed. We sought to analyze this complication in a contemporary HGG cohort.

METHODS

We performed a retrospective review of patients with HGG treated between 2007 and 2013, identified patients with space-occupying tumor bed cysts, and reviewed their hospital notes for relevant variables. Statistical analyses were performed, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.

RESULTS

Tumor bed cysts were found in 12 of 282 patients (4%). The main symptoms were increased intracranial pressure (n = 11), new focal deficits (n = 6), and pseudomeningocele (n = 3), presenting at a median of 19 days since the last resection. Cysts were treated with cystoperitoneal (n = 7) and ventriculoperitoneal (n = 5) shunts, resulting in clinical benefit in 75% of those treated. Intraoperative opening of ventricles is a risk factor, with an OR of 39.339. We propose a classification system comprising 3 cyst types: isolated cyst, cyst with local cerebrospinal fluid (CSF) disturbance, and cyst with global CSF disturbance.

CONCLUSIONS

In modern neuro-oncology, the rate of tumor bed cysts complicating HGG management appears stable compared with historical data. Shunt implantation is feasible and effective. We propose a classification system as a common data element for comparison across future studies.

Iatrogenic postoperative cerebellar cyst

Cerebellar cyst is a known but uncommon entity. It is congenital in most cases, or may develop after brain parenchyma injuries or interventions. To our knowledge, de novo cerebellar cyst after extra-axial tumor excision, has not been described in the literature. We present the first reported case of a de novo cerebellar cyst developing in a 70-year-old woman following retrosigmoid craniotomy for vestibular schwannoma excision, and discuss the possible causes. Following cyst fenestration, there was no clinical or radiological evidence of a residual cyst.

Chronic Phase Intracranial Hemorrhage Caused by Ruptured Pseudoaneurysm Induced by Carmustine Wafer Implantation for Insulo-opercular Anaplastic Astrocytoma: A Case Report

Carmustine wafers improve the survival of patients with high-grade gliomas, but several adverse events have been reported. A 42-year-old man with left insulo-opercular anaplastic astrocytoma developed a massive intra-cavital hematoma with subarachnoid hemorrhage caused by ruptured pseudoaneurysm of the left middle cerebral artery (MCA) adjacent to the site of carmustine wafers implanted 6 months previously. Intraoperative finding demonstrated a dissection of the insular portion of the MCA, and pathological examination identified the resected pseudoaneurysm. This case demonstrates that carmustine wafers can cause changes in local vessels. Therefore, implantation of carmustine wafers near to important vessels passing close to the resection cavity should be considered with great caution.

Double-edged Sword in the Placement of Carmustine (BCNU) Wafers along the Eloquent Area: A Case Report

Although direct Gliadel^® wafer implantation into the resection cavity has been shown to significantly improve survival in patients with high-grade gliomas, several complications have been associated with the implantations of Gliadel wafers, including brain edema, healing delay, cerebral spinal fluid leak, intracranial infections, and cyst formation. The brain edema that is associated with Gliadel wafer implantation might result in neurological deficits and significant morbidities and mortalities. In particular, it is not clear if they should be placed in the eloquent areas, such as language areas, motor areas, and areas related to cognitive function, even if these areas contain a remnant tumor. Here, we present a case of profound brain edema along the pyramidal tract due to Gliadel wafer implantation, which resulted in severe neurological deficits. This treatment represents a double-edged sword due to the possibility of severe symptomatic brain edema along the eloquent area, even though Gliadel wafers might be effective in controlling local tumor growth. We should keep in mind that Gliadel wafer placement in eloquent areas may result in severe disadvantages to patients and a loss of their quality of life.

Cerebral Infarction Related to Carmustine Wafers in Glioblastoma: A Case Report

Implantation of carmustine-impregnated wafers (Gliadel^®) into the tumor resection cavity has demonstrated a survival benefit for patients with malignant glioma. However, some precautions should be taken regarding Gliadel implantation. We report a case of a 63-year-old man with glioblastoma who was implanted with Gliadel after a left temporal lobe tumor had been removed, and who later developed vasospasm of the lenticulostriate artery close to the implanted Gliadel, leading to serious cerebral infarction. Therefore, the implantation of Gliadel in cases where important vessels run close to the resection cavity should be considered with great caution.

Neurosurgical oncology: advances in operative technologies and adjuncts

Modern glioma surgery has evolved around the central tenet of safely maximizing resection. Recent surgical adjuncts have focused on increasing the maximum extent of resection while minimizing risk to functional brain. Technologies such as cortical and subcortical stimulation mapping, intraoperative magnetic resonance imaging, functional neuronavigation, navigable intraoperative ultrasound, neuroendoscopy, and fluorescence-guided resection have been developed to augment the identification of tumor while preserving brain anatomy and function. However, whether these technologies offer additional long-term benefits to glioma patients remains to be determined. Here we review advances over the past decade in operative technologies that have offered the most promising benefits for glioblastoma patients.

Growth pattern of tumor recurrence following bis-chloroethylnitrosourea (BCNU) wafer implantation in malignant glioma

Bis-chloroethylnitrosourea (BCNU; Gliadel, Eisai, Tokyo, Japan) is the only therapeutic agent for local chemotherapy of malignant gliomas approved by the US Food and Drug Administration and the European Medicines Agency. In a small patient cohort, it has previously been shown that glioblastomas recur locally despite treatment with BCNU. This raises concern about local treatment with BCNU as a stand-alone measure. The goal of this study was to analyze the growth pattern of tumor recurrence in a larger patient group: 41 patients were included in this study. Tumor recurrences were morphologically categorized as: local, diffuse, distant or multilocular. Thirty-three of the tumors (80%) that recurred were local or diffuse. These results show that BCNU implantation does not provide lasting local tumor control. Our data support the need to incorporate BCNU in to multimodal therapy schemes. The improved survival rates of patients who receive concomitant local and systemic adjuvant treatment support using local therapy to bridge the therapy-free interval of the initial postoperative phase.

Safety and efficacy of concomitant chemotherapeutic wafers and iodine-125 seeds for recurrent glioblastoma

Background:

Patients with recurrent malignant gliomas have a uniformly poor prognosis. However, further treatment is often warranted at the time of recurrence. Low-activity implanted brachytherapeutic devices, such as iodine-125 seeds, and implantable chemotherapeutic devices such as 1, 3-bis (2-chloroethyl)-nitrosourea (BCNU) impregnated polymer wafers (Gliadel^®) have been shown to be safe and modestly effective, but a comparison of combination therapy versus Gliadel^® implantation alone has not been performed.

Methods:

We retrospectively examined 24 patients following re-resection of recurrent glioblastoma, with 17 patients undergoing implantation of both Gliadel^® and iodine-125 seeds, and 7 patients undergoing implantation of Gliadel^® only. Outcomes examined included adverse events, survival after re-resection (SAR), and time to tumor progression after re-resection (PAR).

Results:

Implantation of both Gliadel^® and low activity iodine-125 seeds is safe with only two wound infections noted, a complication rate comparable to previous reports. The combination appears to confer a median SAR benefit if the activity per tumor resection volume exceeds 0.8 mCi/mL (60 versus 31 weeks, P = 0.02), and this benefit remained significant on multivariate analysis (HR =0.26 [CI:0.07-0.93], P = 0.03). Gross total resection of tumor was also significantly associated with longer time to PAR (HR =5.4 [CI: 1.13-26.0], P = 0.03).

Conclusions:

The concomitant use of Gliadel^® and low activity iodine-125 seeds following re-resection of recurrent glioblastoma is safe. Our study demonstrated a significant benefit in SAR if the iodine-125 activity per tumor volume is greater than 0.8 mCi/mL. While our sample size is small, our results are in agreement with previous studies demonstrating the efficacy of combination treatment.

Temporal changes in magnetic resonance imaging characteristics of Gliadel wafers and of the adjacent brain parenchyma

Carmustine is used in the treatment of glioblastomas as locally applied chemotherapy in the form of biodegradable wafers, which are lined on the walls of the resection cavity at the end of the resection, to increase local concentrations and decrease systemic toxicity. A total of 44 patients with glioblastoma with gross macroscopic tumor removal were included. MRIs were performed at various times postoperatively (within 24 hours, 1 week, 1 month, 2 months, 3 months, 6 months, 9 months, and 1 year). MR protocols included a T2-, diffusion-weighted, and T1-weighted sequences with and without intravenous administration of gadolinium. On T1, the wafers change from their initial hypointense to an isointense appearance after a period during which they appear to be hypointense, with a hyperintense rim most prominent less than 1 month postoperatively. On T2 they change from a hypointense to an isointense appearance. Restricted diffusivity reshaping the silhouette of the wafer's surface at the rim of the resection cavity can be found as early as day 1 postoperatively; however, 1 month after implantation, they all show areas of restricted diffusion, which may remain up to 1 year. Contrast enhancement at the rim of the resection cavity can already be found at day 1 postoperatively, with a peak shortly after 1 month after surgery. These changes can easily be mistaken for an abscess and hamper the early differentiation between residual tumor tissue and normal postoperative changes. However, early changes in either appearance do not predict overall survival or the progression free interval.

Space-occupying cyst development in the resection cavity of malignant gliomas following Gliadel® implantation--incidence, therapeutic strategies, and outcome

Gliadel® (Eisai Inc., Woodcliff Lake, NJ, USA) is the only therapeutic agent approved by the Food and Drug Administration and the European Medicines Agency for local chemotherapy of malignant gliomas. With increasing use of this treatment, characteristic side effects have become evident. While most side effects can be managed conservatively, cyst formation requires further intervention. From 2004 to 2009 at our institution 88 patients with malignant gliomas were treated with Gliadel®. Ten patients (11%) developed a space-occupying cyst in the resection cavity, seven of which caused clinical symptoms of mass effect that was most prominent 2 weeks after Gliadel® implantation (median=16, range=9-30). Despite dexamethasone treatment symptoms progressed, necessitating various surgical interventions. In four patients the cysts were drained percutaneously through a burrhole using a 19-gauge needle. If puncture was not possible (three patients) or not sufficient (two patients), an Ommaya reservoir was implanted for repetitive drainage. In two patients this treatment was combined with open decompression of the cyst. On average, cysts were drained three times. Eventually the symptoms subsided, corresponding to shrinkage of the cysts as shown on follow-up imaging. We describe a serious side effect of local chemotherapy, which may cause rapid clinical deterioration and require direct intervention. While reservoir implantation apparently represents a more elegant treatment option, our experience shows that draining the cyst, even only a few times, sufficiently ameliorates the symptoms and subsequently reverses and halts further cyst enlargement.

Expanding cerebrospinal fluid cyst in the operative cavity: an unusual postoperative complication

We present two cases of expanding cerebrospinal fluid (CSF) cyst formation appearing as a local complication after supratentorial craniotomy for complete brain tumour removal. Surgical treatment was simple and effective. Diagnosis was less obvious due to apparently normal radiological patterns and the absence of an expanding mass. CSF cysts should be included in the differential diagnosis of postoperative complications, particularly when neuroradiographic findings are inconclusive.

The first 3 months after BCNU wafers implantation in high-grade glioma patients: clinical and radiological considerations on a clinical series

PURPOSE

Carmustine (1,3-bis[2-chloroetyl]-1-nitrosurea (BCNU)) wafers are approved for the local treatment of newly diagnosed and recurrent malignant glioma. Reassuring data on both safety and efficacy of treatment have been previously reported by phase III studies. Although most of related adverse events are reported in the first few months after surgery, there is a lack in the literature of radiological data regarding this period. Few anecdotal experiences have been reported about surgical bed cyst occurrence. The aim of our study is to analyse the radiological course of patients treated with wafers implantation focusing on the relationship between radiological data, and in particular bed cyst occurrence, and safety data.

METHODS

Forty-three patients affected by malignant glioma underwent surgical removal and BCNU wafers implantation at the Department of Neurosurgery of Padova from April 2007 to October 2009. Safety data were collected according to previously reported phase III studies. Patients underwent clinical and radiological evaluation (MRI) postoperatively, then before discharge, at 1 month, then every 2 months. In the study were included only patients whose both 1- and 3-month MRIs were available. Finally, 36 out of 43 patients were available for the revision.

FINDINGS

Fifty-eight percent of patients treated with BCNU wafers presented a bed cyst of the surgical cave at the 1-month MRI. Forty-eight percent of them were symptomatic. Conversely, among patients who presented one or more adverse event (27%), bed cyst was detected in up to 90% of cases (OR 7.35), being intracranial hypertension more frequently associated (OR 7.35; p value <0.05). In general, cysts presented a benign behaviour in the sense that patients promptly improved with corticosteroid treatment, never required surgery, never reported permanent neurological deficits.

CONCLUSIONS

Surgical bed cyst occurrence in BCNU wafer-treated patients resulted more frequent than expected. Familiarity with the event is important to correctly handle a possible evolving phenomenon. However, only further larger experiences and prospective studies could reveal how the understanding of such event might be helpful to improve safety data.

Reoperation as a result of raised intracranial pressure associated with cyst formation in tumor cavity after intracranial tumor resection: a report of two cases

Reoperation as a result of increased intracranial pressure (ICP) associated with cyst formation in an intracranial tumor resection cavity is a rare clinical condition. We report two cases of reoperation as a result of raised ICP associated with cyst formation in the tumor resection cavity, one arising after glioma resection and the other after meningioma resection. In both cases, a "valve"-like structure was noted intraoperatively in the roof region of the tumor resection cavity. Surgical resection of the "valve"-like structure led to slow regression over several months after the reoperation rather than to immediate disappearance of the cyst. Both cases illustrate that the "valve"-like structure formed in the roof region of the tumor resection cavity may be responsible for cyst formation. Surgical resection of it provides good long-term outcomes in such patients though short-term outcomes are unsatisfactory; we speculate that if the resection of the cortical tissue around the "valve"-like structure is enough wide, its return may be avoided.

Carmustine wafers: localized delivery of chemotherapeutic agents in CNS malignancies

High-grade glioma is a devastating disease that leaves the majority of its victims dead within 2 years. To meaningfully increase survival, a trimodality approach of surgery, radiation, and chemotherapy is needed. Carmustine (1,3-bis (2-chloroethyl)-1-nitrosourea) is a nitrosourea alkylating agent that exerts its antitumor effect by akylating DNA and RNA. Systemic administration of nitrosoureas as a single agent or as part of procarbazine/3-cyclohexyl-1-nitroso-urea/vincristine has demonstrated little efficacy in the treatment of high-grade glioma. The development of carmustine wafers (Gliadel((R)) Wafer) as a method for controlled released delivery of carmustine from biodegradable polymer wafers enhances the therapeutic ratio by fully containing the drug within the confines of the brain tumor environment while minimizing systemic toxicities. Preclinical and clinical studies have proven the safety and efficacy of Gliadel in the management of glioblastoma. From these results, Gliadel is currently approved for use in patients with recurrent glioblastoma as an adjunct to surgery and in newly diagnosed patients with high-grade glioma as an adjunct to surgery and radiation. Other promising advances in the use of locally delivered chemotherapy for CNS malignancies, including Gliadel for brain metastases and combination therapies with systemic or biologic agents, are discussed.

Stent placement for intracranial cysts by combined stereotactic/endoscopic surgery

OBJECTIVE

The treatment of space-occupying cystic lesions includes percutaneous cyst aspiration, marsupialization, percutaneous ventriculocystotomy, or Rickham catheter implantation. In some patients, the cysts tend to recur and repeated evacuations are necessary. The authors present a new treatment method with internal drainage of cysts into the ventricular system using a balloon-mounted vascular stent.

METHODS

Six patients with cysts of low-grade gliomas, one with monocystic craniopharyngioma, and one with suprasellar arachnoid cyst were treated between September 2003 and May 2005. All patients were symptomatic after multiple previous treatments. Stent implantations were performed under local anesthesia in adults and under general anesthesia in children. In all patients, the stereotactic frame and computed tomographic and magnetic resonance fusion were used for an optimized approach. The treatment was performed in a compassionate manner and the patients were informed about the off-label use of the device.

RESULTS

Stent placement was successful in all eight patients without procedure-related complications. Improvement of clinical symptoms was seen in seven out of eight patients. Seven out of eight cysts decreased in size within a follow-up period of up to 23 months (mean, 17 mo; median, 18 mo; range, 6-23 mo). The first patient showed recurrence of the tumor cyst 3 months after initial treatment with a Herkulink stent (5 x 18 mm), followed by retreatment with an Omnilink stent (6 x 28 mm; Guidant Corp., Santa Clara, CA). Stenting was ineffective in one patient.

CONCLUSION

Treatment of intracranial cystic lesions by internal drainage is possible with the use of stent-assisted ventriculocystostomy.

Sustained radiographic and clinical response in patient with bifrontal recurrent glioblastoma multiforme with intracerebral infusion of the recombinant targeted toxin TP-38: case study

Glioblastoma multiforme remains refractory to conventional therapy, and novel therapeutic modalities are desperately needed. TP-38 is a recombinant chimeric protein containing a genetically engineered form of the cytotoxic Pseudomonas exotoxin fused to transforming growth factor (TGF)-alpha. TGF-alpha binds with high affinity to the epidermal growth factor receptor, which is uniformly overexpressed in malignant gliomas, often because of gene amplification. Prior to therapy with TP-38, the patient described here was completely refractory to multiple other therapies, with radiographic and pathologic evidence of tumor progression. After therapy, she improved clinically, was weaned off steroids and anti-convulsants, and experienced a progressive decrease in enhancing tumor volume. Despite multiple prior recurrences, she has not progressed for >43 months after TP-38 therapy. Small remaining areas of enhancement demonstrate no evidence of tumor histologically and are hypometabolic on positron emission tomography. This report describes a dramatic and sustained clinical and radiographic response in a patient with a bifrontal glioblastoma multiforme treated with intratumoral infusion of a novel targeted toxin, TP-38.