Safety and Efficacy of Hypo Fractionated Stereotactic Radiosurgery in Facial Nerve Schwannoma: a Single Institution Retrospective Case Series

Background: In the current era of modern neurosurgery, the treatment strategies have been shifted to “nerve-preservation approaches” for achieving a higher facial and hearing function preservation rate following facial nerve tumors.Objective: We have conducted this novel report on determining the outcome of patients with facial nerve schwannomas (FNS) treated with hypo fractionated stereotactic radiosurgery (hfSRS).Methods: Retrospective chart review of a prospectively maintained database search was conducted. Patients who underwent hfSRS CyberKnife (Accuray Inc, Sunnyvale, California., USA) for FNS were included. Outcomes consisted of tumor control, facial and hearing nerve function as graded by House-Brackmann (HB) and Gardner-Robertson scale, and adverse radiation effects. SPSS 23 was used to perform statistical analysis.Results: With an institutional board review approval, we retrospectively identified 5 patients with FNS [4 intracranial (80%) and 1 extracranial (20%)] treated with hfSRS (2011-2019). Patients received definitive SRS in 3 patients (60.0%) wile adjuvant to surgical resection in 2 patients (40.0%). A median tumor volume of 7.5 cm3 (range, 1.5-19.6 cm3) received a median prescription dose of 23.2 Gy (range, 21-25 Gy) administered in median of 3 fractions (range, 3-5 session). With a median radiographic follow-up of 31.4 months (range, 13.0-71.0 months) and clinical follow-up of 32.6 months (range, 15.1-72.0 months), the local tumor control was 100.0%. At last clinical follow-up, the facial nerve function improved or remained unchanged HB I-II in 80.0% of the patients, while the hearing nerve function improved or remained stable in 100.0% (Gardner-Robertson I-II) of the patients. Temporary clinical toxicity was seen in 3 patients (60.0%) which resolved. None of the patient developed adverse radiation effect.Conclusion: From our case series, hfSRS in FNS seems to be safe and efficacious in terms of local tumor control, and improved facial and hearing nerve function.

Hearing Rehabilitation with Cochlear Implants after CyberKnife Radiosurgery of Vestibular Schwannoma: A Report Based on Four Clinical Cases

Severe sensorineural hearing loss can be a symptom of the benign tumor vestibular schwannoma (VS). The treatment of VS with non-invasive stereotactic radiosurgery (SRS) offers a high local tumor control rate and an innovative possibility of sequential hearing rehabilitation with cochlear implantation. This study evaluated the feasibility, complications, and auditory outcomes of such a therapeutic approach. Three males and one female (mean age 65.3 ± 9.4 years) scheduled for cochlear implantation and diagnosed with sporadic VS classified as T1 or T2 (according to Samii) were enrolled in this study. All patients had progressive hearing loss qualifying them for cochlear implantation. First, the tumor was treated using CyberKnife SRS. Next, sequential auditory rehabilitation with a cochlear implant (CI) was performed. Clinical outcomes and surgical feasibility were analyzed, and audiological results were evaluated using pure tone audiometry and speech recognition tests. All patients exhibited open-set speech understanding. The mean word recognition score (at 65 dB SPL, Freiburg Monosyllabic Test, FMT) improved after cochlear implantation in all four patients from 5.0 ± 10% (with hearing aid) preoperatively to 60.0 ± 22.7% six months postoperatively. Our results suggest that in patients with profound hearing loss caused by sporadic vestibular schwannoma, the tumor removal with SRS followed by cochlear implantation is an effective method of auditory rehabilitation.

STMO-17 Treatment outcome of photodynamic therapy using talaporfin sodium for recurrent high-grade glioma

Objective: Photodynamic therapy (PDT) using Talaporfin Sodium (TS) is a novel therapeutic strategy to improve local tumor control in high-grade glioma. TS is a photosensitizer that accumulates in tumor cells and produces highly toxic free radicals by intraoperative irradiation of laser with a 664nm wavelength. However, little is known about the treatment outcomes of PDT in recurrent high-grade gliomas (rHGG). In this study, we investigated the treatment outcome of PDT in rHGG and evaluated the correlation between intratumoral TS accumulation and outcomes. Methods: We included 21 patients with rHGG and 22 tumors, who were treated by PDT between June 2016 and March 2021. TS was transvenously administered 22–26 hours before PDT. Intratumoral TS concentrations were measured by liquid chromatography using frozen tissue. Results: The rHGGs included 10 glioblastoma, IDH1/2-wildtype (GBM, IDH1/2-WT: 45.5%), 3 GBM, IDH1/2-mutant (GBM, IDH1/2-Mut: 13.6%), 7 anaplastic oligodendroglioma, IDH1/2-Mut/codel (AO, IDH1/2-Mut/codel: 31.8%), 1 anaplastic astrocytoma, IDH1/2-WT (AA, IDH1/2-WT: 4.5%), 1 high-grade astrocytoma, IDH1/2-WT (4.5%). The median local progression free survival (PFS) time after PDT was 3.6 months and the median survival time from PDT was 19.4 months. The intratumoral TS concentrations of 7 tumors (TS(-): 31.8%) were below the limit of quantification, and the intratumoral TS concentrations of the remaining 15 tumors (TS(+)) were 43.5 ng/mg-protein (14.7–132 ng/mg-protein). The intratumoral TS concentrations were not significantly associated with IDH1/2 mutation status, cellularity, tumor grade, and pattern of enhancement. The median PFS from PDT tended to be longer in TS(+) than in TS(-) (TS(+): 6.3 vs TS(-): 1.4 months, p = 0.054). Conclusions: We found that the intratumoral TS concentrations were heterogeneous and 31.8% were below the limit of quantification. TS(+) tended to have better local tumor control than TS(-), suggesting the intratumoral TS accumulation have an impact of treatment outcomes of PDT.

Late Toxicities, Failure Patterns, Local Tumor Control, and Survival of Esophageal Squamous Cell Carcinoma Patients After Chemoradiotherapy With a Simultaneous Integrated Boost: A 5-Year Phase II Study

PurposeWe aimed to evaluate the long-term outcomes of concurrent chemoradiotherapy (CCRT) with a simultaneous integrated boost (SIB) of radiotherapy for esophageal squamous cell carcinoma (ESCC).Methods and MaterialsEighty-seven patients with primary ESCC enrolled in this phase II trial. The majority (92.0%) had locoregionally advanced disease. They underwent definitive chemoradiotherapy. The radiotherapy doses were 66 Gy for the gross tumor and 54 Gy for the subclinical disease. Doses were simultaneously administered in 30 fractions over 6 weeks. The patients also underwent concurrent and adjuvant chemotherapy, which comprised cisplatin and fluorouracil. The study end points were acute and late toxicities, first site of failure, locoregional tumor control, and overall survival rates.ResultsThe median follow-up time was 65.7 (range, 2.2-97.5) months for all patients and 81.5 (range, 19.4-97.5) months for those alive. There were 17 cases (19.5%) of severe late toxicities, including four cases (4.6%) of grade 5 and seven (8.0%) of grade 3 esophageal ulceration, four (4.6%) of grade 3 esophageal stricture, and two (2.3%) of grade 3 radiation-induced pneumonia. Twenty-three (26.4%) patients had locoregional disease progression. Most (86.7%) locally progressive lesions were within the dose-escalation region in the initial radiation plan, while majority of the recurrent lymph nodes were found out-of-field (83.3%) and in the supraclavicular region (75.0%). The 1-, 2-, 3-, and 5-year locoregional tumor control and overall survival rates were 79.2%, 72.4%, 72.4%, 70.8%, and 82.8%, 66.6%, 61.9%, 58.4%, respectively. Incomplete tumor response, which was assessed immediately after CCRT was an independent risk predictor of disease progression and death in ESCC patients.ConclusionsCCRT with SIB was well tolerated in ESCC patients during treatment and long-term follow-up. Moreover, patients who underwent CCRT with SIB exhibited improved local tumor control and had better survival outcomes compared to historical data of those who had standard-dose radiotherapy.

Molecular Response to Combined Molecular- and External Radiotherapy in Head and Neck Squamous Cell Carcinoma (HNSCC)

Combination treatment of molecular targeted and external radiotherapy is a promising strategy and was shown to improve local tumor control in a HNSCC xenograft model. To enhance the therapeutic value of this approach, this study investigated the underlying molecular response. Subcutaneous HNSCC FaDuDD xenografts were treated with single or combination therapy (X-ray: 0, 2, 4 Gy; anti-EGFR antibody (Cetuximab) (un-)labeled with Yttrium-90 (90Y)). Tumors were excised 24 h post respective treatment. Residual DNA double strand breaks (DSB), mRNA expression of DNA damage response related genes, immunoblotting, tumor histology, and immunohistological staining were analyzed. An increase in number and complexity of residual DNA DSB was observed in FaDuDD tumors exposed to the combination treatment of external irradiation and 90Y-Cetuximab relative to controls. The increase was observed in a low oxygenated area, suggesting the expansion of DNA DSB damages. Upregulation of genes encoding p21cip1/waf1 (CDKN1A) and GADD45α (GADD45A) was determined in the combination treatment group, and immunoblotting as well as immunohistochemistry confirmed the upregulation of p21cip1/waf1. The increase in residual γH2AX foci leads to the blockage of cell cycle transition and subsequently to cell death, which could be observed in the upregulation of p21cip1/waf1 expression and an elevated number of cleaved caspase-3 positive cells. Overall, a complex interplay between DNA damage repair and programmed cell death accounts for the potential benefit of the combination therapy using 90Y-Cetuximab and external radiotherapy.

Stereotactic Radiosurgery Versus Active Surveillance for Asymptomatic, Skull-Based Meningiomas: An International, Multicenter Matched Cohort Study

Objective: The optimal management of asymptomatic, skull-based meningiomas is not well defined. The aim of this study is to compare the imaging and clinical outcomes of patients with asymptomatic, skull-based meningiomas managed either with upfront stereotactic radiosurgery (SRS) or active surveillance.Methods: This retrospective, multicenter study involved patients with asymptomatic, skull-based meningiomas. The study end-points included local tumor control and the development of new neurological deficits attributable to the tumor. Factors associated with tumor progression and neurological morbidity were also analyzed.Results: The combined unmatched cohort included 417 patients. Following propensity score matching for age, tumor volume, and follow-up 110 patients remained in each cohort. Tumor control was achieved in 98.2% and 61.8% of the SRS and active surveillance cohorts, respectively. SRS was associated with superior local tumor control (p<0.001, HR=0.01, 95% CI=0.002-0.13) compared to active surveillance. Three patients (2.7%) in the SRS cohort and six (5.5%) in the active surveillance cohort exhibited neurological deterioration. One (0.9 %) patient in the SRS-treated and 11 (10%) patients in the active surveillance cohort required surgical management of their meningioma during follow-up.Conclusions: SRS is associated with superior local control of asymptomatic, skull-based meningiomas as compared to active surveillance and does so with low morbidity rates. Active surveillance with regular neuroimaging studies does not always detect tumor growth before symptomatic progression. SRS should be considered as an alternative to active surveillance at diagnosis of an asymptomatic skull base meningioma. If active surveillance is initially chosen, SRS should be recommended when tumor growth from the original presenting volume is noted during follow-up.

High-Dose Rate Interstitial Spine Brachytherapy Using an Intraoperative Mobile Computed Tomography-Guided Surgical Navigation System

BACKGROUND Up to 15% of previously irradiated metastatic spine tumors will progress. Re-irradiation of these tumors poses a significant risk of exceeding the radiation tolerance to the spinal cord. High-dose rate (HDR) brachytherapy is a treatment alternative. OBJECTIVE To develop a novel HDR spine brachytherapy technique using an intraoperative computed tomography-guided navigation (iCT navigation). METHODS Patients with progressive metastatic spine tumors were included in the study. HDR brachytherapy catheters were placed under iCT navigation. CT-based planning with magnetic resonance imaging fusion was performed to ensure conformal dose delivery to the target while sparing normal tissue, including the spinal cord. Patients received single fraction radiation treatment. RESULTS Five patients with thoracolumbar tumors were treated with HDR brachytherapy. Four patients previously received radiotherapy to the same spinal level. Preimplant plans demonstrated median clinical target volume (CTV) D90 of 116.5% (110.8%-147.7%), V100 of 95.7% (95.5%-99.6%), and Dmax of 8.08 Gy (7.65-9.8 Gy) to the spinal cord/cauda equina. Postimplant plans provided median CTV D90 of 113.8% (93.6%-120.1%), V100 of 95.9% (87%-99%), and Dmax of 9.48 Gy (6.5-10.3 Gy) to cord/cauda equina. Patients who presented with back pain (n = 3) noted symptomatic improvement at a median follow-up of 22 d after treatment. Four patients demonstrated local tumor control of spinal metastatic tumor at a median follow-up of 92 d after treatment. One patient demonstrated radiographic evidence of local tumor progression 2.7 mo after treatment. CONCLUSION HDR spine brachytherapy with iCT navigation is a promising treatment alternative to induce local tumor control and reduce pain symptoms associated with metastatic spine disease.

Association between Time to Local Tumor Control and Treatment Outcomes Following Repeated Loco-Regional Treatment Session in Patients with Hepatocellular Carcinoma: A RETROSPECTIVE, Single-Center Study

Background: Whether the number of loco-regional treatment sessions and the time required to obtain local tumor control (LTC) affects the prognosis of patients with hepatocellular carcinoma (HCC) remains controversial. This study aimed to determine whether a longer time to LTC is a significant and independent predictor of poor treatment outcomes. Methods: In this retrospective study, we analyzed data of 139 treatment-naive patients with HCC who were not eligible for a treatment other than transarterial chemoembolization (TACE) at baseline. The outcome analyses were performed using the Cox proportional hazard model and Kaplan–Meier method, while the overall survival (OS) and progression free survival (PFS) were the primary study endpoints. Results: Overall, LTC was achieved in 82 (59%) of patients, including 67 (81%) patients who achieved LTC following TACE sessions alone and 15 (19%) subjects required additional ablation session. The median OS did not differ significantly between groups that needed 2, 3, or >3 locoregional treatment sessions to achieve LTC (p = 0.37). Longer time to LTC (in weeks) was significantly associated with shorter OS in univariate analysis (p = 0.04), but not in an adjusted model (p = 0.14). Both univariate and adjusted analyses showed that longer time to reach LTC was significantly associated with shorter PFS (adjusted HR = 1.04, 95% CI 1.001–1.09, p = 0.048). Conclusions: These findings show that the longer time to LTC is not an independent predictor of OS, but suggest that PFS may be significantly shorter in patients with longer time to LTC.

The Role of a Navigational Radiofrequency Ablation Device and Concurrent Vertebral Augmentation for Treatment of Difficult-to-Reach Spinal Metastases

Aims: The purpose of this study was to assess the effectiveness of a navigational radiofrequency ablation device with concurrent vertebral augmentation in the treatment of posterior vertebral body metastatic lesions, which are technically difficult to access. Primary outcomes of the study were evaluation of pain palliation and radiologic assessment of local tumor control. Materials and Methods: Thirty-five patients with 41 vertebral spinal metastases involving the posterior vertebral body underwent computed tomography-guided percutaneous targeted radiofrequency ablation, with a navigational radiofrequency ablation device, associated with vertebral augmentation. Twenty-one patients (60%) had 1 or 2 metastatic lesions (Group A) and fourteen (40%) patients had multiple (>2) vertebral lesions (Group B). Changes in pain severity were evaluated by visual analog scale (VAS). Metastatic lesions were evaluated in terms of radiological local control. Results: The procedure was technically successful in all the treated vertebrae. Among the symptomatic patients, the mean VAS score dropped from 5.7 (95% CI 4.9–6.5) before tRFA and to 0.9 (95% CI 0.4–1.3) after tRFA (p < 0.001). The mean decrease in VAS score between baseline and one week follow up was 4.8 (95% CI 4.2–5.4). VAS decrease over time between one week and one year following radiofrequency ablation was similar, suggesting that pain relief was immediate and durable. Neither patients with 1–2 vertebral metastases, nor those with multiple lesions, showed radiological signs of local progression or recurrence of the tumor in the index vertebrae during a median follow up of 19 months (4–46 months) and 10 months (4–37 months), respectively. Conclusion: Treatment of spinal metastases with a navigational radiofrequency ablation device and vertebral augmentation can be used to obtain local tumor control with immediate and durable pain relief, providing effective treatment in the multimodality management of difficult-to-reach spinal metastases.