Results Of Gamma Knife Radiosurgery Research Articles

Gamma knife radiosurgery for orbital cavernous hemangioma: a systematic review and single-arm meta-analysis.

Gamma knife radiosurgery (GKRS) for orbital cavernous hemangioma (OCH) has emerged as a promising method due to its significant clinical improvement and low incidence of complications. This study aimed to evaluate the safety and efficacy of GKRS for the treatment of OCH. In accordance with the PRISMA framework, we searched PubMed, Cochrane Central, and Embase for studies reporting outcomes of GKRS for OCH. Studies reporting complications, visual improvement, proptosis, tumor reduction rate, and tumor progression rate for OCH following GKRS were included. Six studies, out of 1856 search results, with 100 patients were included. Among them, only 5 minor complications were related to GKRS, including 3 with orbital pain and 2 with periorbital chemosis. Thus, the complication rate was 13% (95% CI, 7-25%). Visual acuity and visual field improvement rates after GKRS were 80% (95% CI, 63-96%) and 71% (95% CI, 47-95%) respectively. Proptosis improved in 94% of cases (95% CI, 83-100%). The tumor reduction rate was 77% after GKRS (95% CI, 69-85%). GKRS for OCH appears to be a safe technique, as evidenced by the rate of clinical improvement and radiological improvement. However, studies are limited by an absence of a control group. Additional studies are needed to evaluate the relative efficacy of GKRS as compared with alternative surgical modalities for OCH.

Gamma Knife Versus Volumetric Arc Modulated Therapy in a Linear Accelerator in Treatment of Multiple Brain Metastasis: Literature Review

This literature review introduces the treatment results of Gamma Knife radiosurgery (GKRS) and volumetric arc therapy (VMAT) administered by linear accelerators for patients diagnosed with multiple brain metastases. The present study aimed to compare Gamma Knife radiosurgery with Volumetric Arc Modulated Therapy (VMAT) administered using a linear accelerator for brain metastases and their respective safety profiles and therapeutic results. The review assesses research on treatment precision, local control rates, survival outcomes, radiation necrosis incidence, and post-treatment quality of life. It evaluates technical progress, treatment plans, and physiological effects on brain tissue. Both modalities have the potential for managing brain metastases, with GKRS being beneficial for well-defined lesions and VMAT being a flexible and efficient option for larger or irregular-shaped metastases. The study highlights the unique benefits of each therapy for different types of brain metastases. GKRS and VMAT are effective treatments for brain metastases, using concentrated radiation for localised lesions and advanced imaging techniques for intricate or expanded regions. GKRS offers precise interventions with minimal invasiveness, suitable for patients with lower metastatic burdens or suboptimal surgical tolerance. Both therapies show similar effectiveness in local control and survival but may be better suited for specific patient needs and lesion characteristics

Gamma Knife radiosurgery for the management of glomus jugulare tumors: A systematic review and report of the experience of a radioneurosurgery unit in Latin America.

Glomus jugulare tumors (GJTs) are rare and mainly affect women between the 5th and 6th decades of life. Its localization and anatomic relationships make conventional surgical treatment difficult and with a considerable risk of complications. This manuscript aims to describe the results of Gamma Knife radiosurgery (GKR) in patients with GJT treated in a single center in Latin America, as well as to systematically review the literature to determine the clinical and radiological effectiveness of this technique. A search of information from January 1995 to June 2023 was performed. Twenty-two articles reporting 721 GJT patients treated with GKR were included in the study. Variables such as symptomatic control, control of tumor size, and complications were evaluated. These variables were described using measures of central tendency and proportions. For the institutional experience, 77 patients with GJT tumors were included in the study. Pre-treatment clinical variables and follow-up data were collected from medical charts and phone interviews. The Short Form-36 scale was applied to assess the quality of life. The data were analyzed using the statistical program STATA17.0. A total of 721 patients were considered. The median of patients included in these studies was 18.5. The mean age was 58.4 years. The median of symptom control was 89%, and the median of imaging control was 95.7%. In our institution, 77 patients were included in the study. The mean age was 53.2 years. The median hospital stay was 4.92 hours. For the clinical follow-up, information on 47 patients was obtained. An improvement in pre-treatment symptoms was described in 58%, with general symptomatic control of 97%. The tumor-control rate was 95%, and there were statistically significant differences in six of the nine Short Form-36 scale domains. GKR is an effective, safe, and cost-effective technique that offers a high degree of symptomatic and tumor size control in patients with GJT.

Long-term outcomes of Gamma Knife radiosurgery in treating glossopharyngeal neuralgia.

Glossopharyngeal neuralgia (GPN) is an unusual disorder causing severe, brief pain episodes in the areas supplied by the glossopharyngeal nerve. Initial treatment involves medications like carbamazepine, but if these are ineffective or cause side effects, interventional pain management techniques or surgery may be considered. Gamma Knife radiosurgery is becoming popular in managing GPN due to its lower risk of complications than surgical interventions like microvascular decompression or rhizotomy. In this retrospective case series, we examined the outcomes of Gamma Knife radiosurgery in eight patients with GPN. The decision to utilize Gamma Knife radiosurgery was made following specific criteria, including failed surgical interventions, patient preference against surgery, or contraindications to surgical procedures. Patients were administered radiation doses within the range of 80 to 90 Gy, targeting either the cisternal glossopharyngeal nerve or glossopharyngeal meatus of the jugular foramen. Evaluations were conducted before the Gamma Knife radiosurgery; at 3, 6, and 12 months after Gamma Knife radiosurgery; and annually thereafter. Pain severity was assessed using the modified Barrow Neurological Institute scale grades, with patients achieving grade I-IIIa considered to have a good treatment outcome and grade IV-V to have a poor treatment outcome. Pain control and absence of radiosurgery-related complications were primary endpoints. The median age of the patients was 46.5 years, varying from 8 to 72 years. The median duration of pain was 32 months (range, 12-120 months). All patients, except one, were on polydrug therapy. All cases exhibited preoperative grade V pain. The median follow-up duration after Gamma Knife radiosurgery was 54.5 months, varying from 14 to 90 months. The overall clinical assessments revealed a gradual neurological improvement, particularly within the first 8.5 weeks (range, 1-12 weeks). The immediate outcomes at 3 months revealed that all patients (8/8, 100%) experienced pain relief, with 25% (2/8) achieving a medication-free status (Grade I). Three patients (37%) experienced a recurrence during the follow-up and were managed with repeat Gamma Knife radiosurgery (n = 2) and radiofrequency rhizotomy (n = 1). At the last follow-up, 88% (7/8) of patients had pain relief (Grades I-IIIa), with three (37%) achieving a medication-free status (Grade I). No adverse events or neurological complications occurred. The patient who underwent radiofrequency rhizotomy continued to experience inadequately controlled pain despite medication (Grade IV). Gamma Knife radiosurgery is a non-invasive, efficacious treatment option for idiopathic GPN, offering short- and long-term relief without permanent complications.

Alexithymia and depression may predict treatment failure in patients undergoing Gamma Knife radiosurgery for trigeminal neuralgia: the potential contribution of colored pain drawings.

Gamma Knife radiosurgery (GKRS) effectively achieves high rates of pain control in trigeminal neuralgia (TN); however, psychological factors can also impact how individuals perceive pain and respond to treatment. The authors aimed to measure the effects of alexithymia and depression on GKRS outcomes, as well as the potential role of colored pain drawings (CPDs) in identifying patients who require additional psychological support. Seventy-three medically intractable, typical patients with TN were included. Participants completed a visual analog scale (VAS), the Toronto Alexithymia Scale (TAS-20), and the Turkish version of the Beck Depression Inventory-II (BDI-II). Participants used colored pens to draw their pain patterns on standardized face charts and CPDs were categorized as expected or unexpected. Based on the Barrow Neurological Institute pain scale, patients were categorized as responders or nonresponders. Most patients (63%) were female, and the median age was 60 (range 27-88) years. Of 73 patients, 56 (76.7%) were responders and 17 (23.3%) were nonresponders. Forty-nine patients (67.1%) had expected CPDs, whereas 24 (32.9%) had unexpected CPDs. Responder and nonresponder groups had similar ages, genders, education, comorbidities, and initial VAS scores. Both groups preferred the colors red and black to describe intense pain (79.2% vs 67.3%, p = 0.411). Significantly better pain relief was observed in patients with expected CPDs than in those with unexpected CPDs (87.8% vs 54.2%, p = 0.003). The unexpected CPD group had significantly more alexithymia (58.3% vs 32.7%, p = 0.045). The mean BDI-II score of the cohort was 26 (range 15-37) and was significantly higher in the unexpected group (28.3 vs 24.8, p = 0.028). Unexpected CPD (OR 12.540) and higher TAS-20 score (OR 3.22) increased treatment failure risk. The outcomes of TN treatment can be influenced by psychological factors, and patients with TN with higher total TAS-20 and BDI-II scores, along with unexpected CPDs, had an increased likelihood of treatment failure. CPDs can be accessed quickly and may allow the physician to screen out most patients with unfavorable psychometrics and proceed with the necessary treatment with appropriate psychological support.

RADT-41. PREDICTION OF TREATMENT OUTCOME IN GAMMA KNIFE RADIOSURGERY OF BENIGN MENINGIOMAS

Abstract Objective This study aimed to assess the predictability of machine learning (ML) ensemble models for the success of Gamma Knife radiosurgery (GKRS) on non-skull base benign meningiomas. METHODS A total of 331 non-skull base benign meningiomas treated primarily with GKRS between 1997 and 2015 were retrospectively analyzed. When a tumor remained not larger than 125% of the initial volume at the last imaging follow-up and no significant change in the high signal intensity area around the tumor, it was classified as 'treatment success (TS).' Univariate correlation and multivariate logistic regression analyses were performed to identify statistically significant prognostic factors. Four ensemble algorithms were trained to predict the outcome of GKRS. The importance of features related to TS was analyzed. RESULTS The median MR imaging follow-up period was 8.6 years. The tumor control and signal change rates were 91.5% and 16.3%, respectively, and the TS rate was 77.6%. The conventional multivariate logistic regression model showed 83.7% accuracy and 37.8% specificity. The ML models had accuracies between 78.0% and 82.2% and specificities between 30.3% and 80.7%, and they were similar to those of conventional logistic regression analyses. The smaller brain volume absorbed more than 14 Gy, and the absence of signal change before GKRS was a favorable prognostic factor for TS in all models. The bagging algorithm with selected features showed the best specificity of 80.7% and the most significant AUC of 0.723. CONCLUSION A bagging ensemble algorithm with selected features had better specificity with similar accuracy than conventional multivariate logistic regression in predicting GKRS outcomes for non-skull base meningiomas.

Feasibility of Gamma Knife Radiosurgery for Brain Arteriovenous Malformations According to Nidus Type.

Gamma Knife radiosurgery (GKRS) is an effective and noninvasive treatment for high-risk arteriovenous malformations (AVMs). Since differences in GKRS outcomes by nidus type are unknown, this study evaluated GKRS feasibility and safety in patients with brain AVMs. This single-center retrospective study included patients with AVM who underwent GKRS between 2008 and 2021. Patients were divided into compact- and diffuse-type groups according to nidus characteristics. We excluded patients who performed GKRS and did not follow-up evaluation with magnetic resonance imaging or digital subtraction angiography within 36 months from the study. We used univariate and multivariate analyses to characterize associations of nidus type with obliteration rate and GKRS-related complications. We enrolled 154 patients (mean age, 32.14±17.17 years; mean post-GKRS follow-up, 52.10±33.67 months) of whom 131 (85.1%) had compact- and 23 (14.9%) diffuse-type nidus AVMs. Of all AVMs, 89 (57.8%) were unruptured, and 65 (42.2%) had ruptured. The mean Spetzler-Martin AVM grades were 2.03±0.95 and 3.39±1.23 for the compact- and diffuse-type groups, respectively (p<0.001). During the follow-up period, AVM-related hemorrhages occurred in four individuals (2.6%), three of whom had compact nidi. Substantial radiation-induced changes and cyst formation were observed in 21 (13.6%) and one patient (0.6%), respectively. The AVM complete obliteration rate was 46.1% across both groups. Post-GKRS complication and complete obliteration rates were not significantly different between nidus types. For diffuse-type nidus AVMs, larger AVM size and volume (p<0.001), lower radiation dose (p<0.001), eloquent area location (p=0.015), and higher Spetzler-Martin grade (p<0.001) were observed. GKRS is a safe and feasible treatment for brain AVMs characterized by both diffuse- and compact-type nidi.

Outcomes of Gamma Knife Radiosurgery for Brain Metastases in the Motor Cortex.

To study the clinical, imaging, and survival outcomes in patients with motor cortex brain metastases treated with stereotactic radiosurgery (SRS). Imaging and clinical data were obtained from our prospective patient registry. Tumor volumes were obtained from serial imaging data. The outcomes of 208 patients with metastases involving the motor cortex who underwent SRS between 2012 and 2021 were analyzed. A total of 279 metastases (0.01 cm 3 -12.18 cm 3 , mean 0.74 cm 3 ) were irradiated. The SRS margin dose varied from 10 to 20 Gy (mean 16.9 Gy). The overall tumor control rate was 97.8%. Perilesional edema was noted in 69 (25%) tumors at presentation. Adverse radiation effects (ARE) were noted in 6% of all tumors but were symptomatic in only 1.4%. Median time to appearance of symptomatic ARE was 8 months. Edema without ARE was observed in 13%. New focal seizures were noted in 5 patients (2%) and new generalized seizures in 1 patient (0.3%). Thirty-six patients (17%) presented with motor deficits. At final follow-up, 32 (85%) were improved or unchanged, 13 (41%) had a normal examination, 10 (31%) had mild deficits, and 9 (28%) still had moderate deficits. New remote brain metastases were found in 31% of patients at a median of 8 months. After treatment, the Karnofsky performance score distribution of the population showed an overall right shift and a median survival of 10 months. Patients with incidentally found brain metastases had significantly better survival than those presenting with deficits (median 13 vs 9 months) ( P = .048). Absence of a neurological deficit, recursive partitioning analysis Class I and II, and dose >18 Gy were each associated with a significant survival advantage. SRS for motor cortex metastases is safe in most patients and effective in providing tumor control. Patients treated before neurological deficits develop show better outcomes.

Outcomes of Gamma Knife Radiosurgery for Drug-Resistant Primary Trigeminal Neuralgia.

To evaluate the result of gamma knife radiosurgery (GKRS) for drug-resistant primary trigeminal neuralgia (TN). Patients who were diagnosed with drug-resistant primary TN were treated with GKRS at the Nuclear Medicine and Oncology Center, Bach Mai Hospital from January 2015 to June 2020. Using the pain rating scale of the Barrow Neurological Institute (BNI), follow-ups and evaluations were conducted at 1 month, 3 months, 6 months, and 9 month, and 1, 2 years, 3 years, and 5 years after radiosurgery. Comparisons of pain levels was performed before and after radiosurgery according to the BNI scale. From January 2015 to June 2020, 33 patients were treated with GKS. There were 23 female patients and 10 male patients; the average age was 61.9. The average onset time of disease was 4.42 years. Among all patients, 84.8% of patients were relieved from pain and 78.8% were pain-free without medication. The mean time for pain relief was 3 months and was not related to the dose of GKS (<80 Gy and ≥80 Gy). The efficacy of pain relief is not related to blood vessel contact with the trigeminal nerve, the dose of GKS, and the onset of disease. The rate of recurrence after the first pain relief was low (14.3%). Gamma knife is an effective method for the treatment of primary drug-resistant TN, especially in elderly patients with underlying medical conditions. The analgesic effect does not depend on the presence of nerve-vascular conflict.

Long-Term Results of Gamma Knife Radiosurgery for Trigeminal Neuralgia

Although the short- to medium-term efficacy of Gamma Knife therapy for drug-resistant essential trigeminal neuralgia has been reported, long-term evaluations are limited. We evaluated patient data obtained at least 10years post-treatment and examined the significance of this treatment using new end points. Among 249 consecutive patients with essential trigeminal neuralgia who were treated with Gamma Knife radiosurgery (retrogasserian target/4-mm single isocenter/90Gy at 100%) at our institution between January 2003 and October 2011, 103 patients who were followed up for at least 10years (mean, 174 [120-219] months) after treatment and whose data were amenable to accurate evaluation, were included in this retrospective study. Herein, we used the Barrow Neurological Institute (BNI) pain intensity scale as a clinical evaluation method for pain and the BNI numbness scale to evaluate complications (namely facial dysesthesia). The initial and final follow-up pain attack cessation (BNI pain intensity score I-IIIa) rate was 82.5% (85 of 103) and 58.2% (60 of 103), respectively. Furthermore, sensory impairment (BNI numbness score≥II) at the last follow-up was observed in 24.3% (25 of 103) of the cases, while very bothersome status (BNI numbness score IV) was observed in 2.9% of the cases. Gamma Knife radiosurgery for essential trigeminal neuralgia showed good therapeutic effects during long-term follow-up. Serious complications of significant concern in the short- to mid-term follow-up, resolved spontaneously. Therefore, the indications for treatment should be expanded to include patients who strongly desire Gamma Knife therapy.

Treatment Outcome of Gamma Knife Radiosurgery for Brain Metastasis from Thyroid Cancer: Favorable Local Control but Poor Survival

Brain metastasis from thyroid cancer (TCBM) is extremely rare; thus, despite a good treatment outcome for thyroid cancer, TCBM has shown poor clinical outcomes. Considering the short survival and poor general condition of patients with TCBM, stereotactic radiosurgery may be preferred to achieve local control. A total of 25 patients with TCBM who underwent Gamma Knife radiosurgery (GKS) were initially included in this study; however, 3 patients were excluded because of a lack of data. There were 7 men (31.8%) and 15 women (68.2%) and the mean age was 63.7 years. The most common type of thyroid cancer histology was papillary carcinoma. Fourteen patients (63.6%) harbored single brain metastatic tumor and 8 (36.3%) had multiple brain metastatic tumors. The mean duration from thyroid cancer diagnosis to detection of brain metastasis was 7.7 years (range, 0-23 years). The median dose of radiation of GKS was 22 Gy (range, 18-25 Gy). There was no radiation-induced complication after GKS. The median overall survival (OS) was 15 months and the 1-year OS of patients with TCBM was 63%, the 2-year OS was 38%, and the 5-year OS was 28%. The 6-month progression-free survival (PFS) for local recurrence of TCBM was 90.4%, the 1-year PFS was 84%, and the 3-year PFS was 84%. GKS showed favorable local control for TCBM. However, the rate of distant brain metastasis was high and median survival of patients with TCBM was only 15 months.

Gamma Knife Radiosurgery for Metastatic Brain Tumors from Uterine Cervical and Endometrial Carcinomas: Histopathological Analysis of Survival and Local Control. A Japanese Multi-Institutional Cooperative and Retrospective Cohort Study

A retrospective comparative analysis of the outcomes of gamma knife radiosurgery (GKRS) for brain metastases from uterine cervical carcinoma (CC) and endometrial carcinoma (EC), investigated the efficacy and prognostic factors for survival and local tumor control. Histopathological analysis was also performed. The authors retrospectively reviewed 61 patients with 260 tumors of CC and 73 patients with 302 tumors of EC who had undergone GKRS. The survival times after GKRS had no difference between CC and EC. Uncontrolled primary cancer was significant unfavorable factor. CC resulted in significantly higher neurological death and post-GKRS neurological deterioration. New lesions appeared intracranially after GKRS, with no significant difference between CC and EC. Local tumor control rates at 6, 12, and 24months after GKRS were 90.0%, 86.6%, and 78.0% for CC and 92.2%, 87.9%, and 86.4% for EC. Primary cancer of CC, more than 7cm3 volume, and prescription dose less than 20Gy were significantly correlated in control failure. Local tumor control rates were significantly lower for squamous cell carcinoma in CC. No significant differences were found between histopathological subtypes of EC. This study established a relationship between the efficacy of GKRS for CC and EC brain metastases and the histopathological. Though, survival time after GKRS has no difference between CC and EC, CC was significantly higher neurogenic death and neurological deterioration after GKRS. Squamous cell carcinoma had a significantly lower rate of local tumor control among all CC, thereby resulting in CC having lower local tumor control than EC.

The role of stereotactic radiosurgery in the multidisciplinary management of pituitary metastases

This study evaluates the role and outcomes of Gamma Knife radiosurgery (GKRS) in the management of pituitary metastases. The records of brain metastases patients who underwent GKRS at the University of Pittsburgh Medical Center during the 10-year interval of 2010-2020 were systematically reviewed. Outcome measures included patient survival, tumor control rate, pituitary hormonal outcomes, visual outcomes, adverse radiation effects (AREs), and need for adjuvant therapy. Eighteen patients with pituitary metastases (eight male; median age of 65.5years) had sufficient clinical follow-up for analysis. The most common primary cancers were non-small cell lung cancer (n = 6) and breast cancer (n = 4). Patients presented with headache (n = 9) and visual difficulties (n = 6). One patient underwent resection before GKRS. The median tumor volume was 0.78cc (range 0.04-6.42cc). The median overall survival after GKRS was 6.5months (range 0.5-58months). The overall survival after GKRS at 3-, 6-, and 12-months were 72.2%, 50.0% and 38.9%, respectively. The tumor control rate was 94.4%. One patient had further progression that required additional GKRS. None of the patients developed AREs after GKRS. GKRS is an effective treatment modality for the multidisciplinary management of patients with pituitary metastases. This minimally-invasive strategy is associated with optimal tumor control rate and low risk to adjacent opticnerves or neurovascular structures.

Outcomes of Gamma Knife radiosurgery for skull base chondrosarcomas: a multi-institutional retrospective study.

Radiotherapy has an essential role in the management of skull base chondrosarcomas (SBCs) after resection. This multi-institutional study evaluated the outcomes of Gamma Knife radiosurgery (GKRS) for histopathologically proven SBCs. Data of patients who underwent GKRS for SBCs at Gamma Knife centers in Japan were retrospectively collected. Patients without a histopathological diagnosis and those who had intracranial metastases from extracranial chondrosarcomas were excluded. Histologically, grade III and some nonconventional variants were identified as aggressive types. The cumulative local control rates (LCRs) and disease-specific survival (DSS) rates were calculated using the Kaplan-Meier method. Factors potentially affecting the LCR were evaluated using the Cox proportional hazards model for bivariate and multivariate analyses. The incidence of radiation-induced adverse effects (RAEs) was calculated as crude rates, and factors associated with RAEs were examined using Fisher's exact test. Fifty-one patients were enrolled, with a median age of 38 years. Thirty patients (59%) were treated with upfront GKRS for residual SBCs after resection (n = 27) or biopsy (n = 3), and 21 (41%) underwent GKRS as a salvage treatment for recurrence. The median tumor volume was 8 cm3. The overall LCRs were 87% at 3 years, 78% at 5 years, and 67% at 10 years after GKRS. A better LCR was associated with a higher prescription dose (p = 0.039) and no history of repeated recurrence before GKRS (p = 0.024). The LCRs among patients with the nonaggressive histological type and treatment with ≥ 16 Gy were 88% at 3 years, 83% at 5 years, and 83% at 10 years. The overall survival rates after GKRS were 96% at 5 years and 83% at 10 years. Although RAEs were observed in 3 patients (6%), no severe RAEs with Common Terminology Criteria for Adverse Events grade 3 or higher were identified. No significant factor was associated with RAEs. GKRS for SBCs has a favorably low risk of RAEs and could be a reasonable therapeutic option for SBC in multimodality management. A sufficient GKRS prescription dose is necessary for higher LCRs. Histological grading and subtype evaluations are important for excluding exceptional SBCs. Patients with conventional SBCs have a long life expectancy and should be observed for life after treatment.

Gamma Knife radiosurgery for metastatic brain tumors from ovarian cancer: histopathological analysis of survival and local control. A Japanese multi-institutional cooperative and retrospective cohort study.

Brain metastasis is rare in ovarian cancer patients. The results of Gamma Knife radiosurgery (GKRS) for the treatment of patients with brain metastases from ovarian cancer were retrospectively analyzed to derive the efficacy and prognostic factors for survival and local tumor control. Further histopathological analysis was also performed. The authors retrospectively reviewed the medical records of 118 patients with 566 tumors who had undergone GKRS at the 10 GKRS institutions in Japan. After the initial GKRS, the median overall survival time was 18.1 months. Multivariate analysis showed that uncontrolled primary cancer (p = 0.003) and multiple intracranial metastases (p = 0.034) were significant unfavorable factors. Ten patients died of uncontrolled brain metastases at a median of 17.1 months. The 6-, 12-, and 24-month neurological death rates were 3.2%, 4.6%, and 11.9%, respectively. The 6-, 12-, and 24-month neurological deterioration rates were 7.2%, 13.5%, and 31.4%, respectively. The 6-, 12-, and 24-month distant brain control failure rates were 20.6%, 40.2%, and 42.3%, respectively. Median tumor volume was 1.6 cm3 and marginal dose was 20 Gy. The 6-, 12-, and 24-month local tumor control rates were 97.6%, 95.2%, and 88.0%, respectively. Peritumoral edema (p = 0.043), more than 7-cm3 volume (p = 0.021), and prescription dose less than 18 Gy (p = 0.014) were factors that were significantly correlated in local tumor control failure. Eight patients had symptomatic radiation injury. The 6-, 12-, and 24-month GKRS-related complication rates were 3.3%, 7.8%, and 12.2%, respectively. Primary ovarian cancer was histopathologically diagnosed for 313 tumors in 69 patients. Serous adenocarcinoma was found in 37 patients and other types in 32 patients. Median survival times were 32.3 months for the serous type and 17.4 months for other types after initial GKRS. Patients with serous-type tumors survived significantly longer than patients with other types (p = 0.039). The 6-, 12-, and 24-month local tumor control rates were 100%, 98.8%, and 98.8%, respectively. Serous-type tumors were a significantly good prognosis factor for local tumor control after GKRS (p = 0.005). This study established a relationship between the efficacy of GKRS treatment for brain metastases and the histological type of primary ovarian cancer. GKRS for ovarian cancer brain metastasis can provide satisfactory survival and local control, especially in cases of serous adenocarcinoma.

Gamma Knife radiosurgery for meningiomas of the confluence of the falx and tentorium.

Meningiomas arising from the confluence of the falx and tentorium (CFT) are a rare and challenging subset of meningiomas. Gamma Knife radiosurgery (GKRS) is well-established as a safe and effective management strategy for intracranial meningiomas, but its role in treating CFT meningiomas is not well-described. This paper reports the largest series focused exclusively on the outcomes of GKRS for CFT meningiomas. We retrospectively identified 20 CFT meningiomas out of 2031 meningioma patients who underwent GKRS at our institution between 1987 and 2021. Tumor control, overall survival (OS), and complications were recorded and analyzed. The median tumor margin dose was 13Gy at the 50% isodose line. The median tumor volume treated was 4.4cc (IQR 3.5-7.7). The median patient age was 58years (range 33-83), the median MRI surveillance duration was 59months (IQR 34-92), and the median overall follow-up duration was 92months (IQR 42-201). The local tumor control rate (PFS) at 5 and 10-years were 100% (N=10) and 83% (N=4), respectively. Eight patients had stable tumor volumes and 11 patients had regression. One patient with a twice-operated tumor had delayed progression at 7.5years and was retreated with GKRS. No patient had adverse radiation effects during the period of MRI surveillance. The 5 and 10-year OS were 100% (N=13) and 100% (N=7), respectively. GKRS is a valuable therapeutic strategy for patients with newly diagnosed CFT meningiomas or progressive residual tumors after surgical resection.

436 Colored Pain Drawing in Patients With Trigeminal Neuralgia and Its Impact on Gamma Knife Radiosurgery Outcomes

INTRODUCTION: Trigeminal neuralgia (TN) is one of the most common causes of facial pain and Gamma Knife radiosurgery (GKRS) has been used for a long time with high pain relief rates. However, psychological processes can influence the pain perception and adversely affect treatment outcome. Colored pain drawing (CPD) is a simple,powerful tool for capturing essential aspects of the subjective pain. METHODS: Fifty consecutive patients with medically intractable, ICHD-3 beta-confirmed TN were included. A numerical pain rate scale (NPRS) was used to assess usual level of pain experienced by the patient. Patients were asked to draw the distribution of usual pain pattern with a colored pen of their choice on two standardized face charts. The patients then underwent GKRS. Follow-up data were obtained by clinical examination and/or telephone questionnaire postoperatively at 1, 3 and 6 months. Outcome results were categorized based on the Barrow Neurological Institute (BNI) pain scale (BNI I–III:good outcomes and BNI IV–V:treatment failure). BNI facial numbness score was used to assess complications. All CPDs were classified as “expected” or “unexpected” based on the patient’s description of pain. RESULTS: The median age was 64 years (range, 27-88) years and the male/female ratio was 3:2. 86% of the patients experienced immediate pain relief within the first 3 months. Of those patients, 39 (90.7%) did not have any pain recurrence (BNI I). At last follow-up, 39 (78%) patients had good treatment outcome and 11 patients (22%) had treatment failure. 96% of the patients did not experience any facial numbness. There were 35 patients with “expected” and 15 patients with “unexpected” CPDs. NPRS scores were not significantly different between groups (p = 0.985). The preference of association of pain with black or red color was distinct and did not differ between two groups (p = 0.08). Patients with “expected” CPDs reported significantly better freedom from pain compared with those with “unexpected” CPDs (p &lt; 0.0001). CONCLUSION: CPDs could serve as clinical acumen for outcomes of GKRS treatment for TN.

Gamma Knife radiosurgery for tuberculum sellae meningiomas: a series of 78 consecutive patients.

Outcomes of Gamma Knife radiosurgery (GKRS) for tuberculum sellae meningiomas (TSMs) have not been reported explicitly within any meningioma series. We present the first and largest TSM series with clinical, radiosurgical, and outcome features for 78 consecutive patients managed with GKRS. Patients who underwent GKRS for TSMs between 2005 and 2021 and had a minimum of 6months of follow-up were included. Medical records, imaging studies, and follow-up examinations were evaluated retrospectively. A total of 78 patients with a median age of 50.5years were included. SRS was conducted as an upfront treatment for 38 patients (48.7%). The median target volume was 1.7 cm3 (range, 0.1-14.6). During a median follow-up of 78.5months, the cumulative PFS rates of the whole cohort at 1, 5, and 10years by Kaplan-Meier analysis were 100%, 97.9%, and 94.5%, respectively. Of 47 patients with impaired vision, improvement and/or preservation of visual acuity, and visual field were achieved in 55.3% and 42.6%, respectively. No new-onset hormonal deficits were observed. Based on our data, SRS represents an effective and safe modality for unresected or recurrent/residual TSMs. SRS should be offered to patients who are not willing or not ideal candidates for surgery.

Gamma Knife radiosurgery for the treatment of cluster headache: a systematic review.

Cluster headache (CH) is a severe trigeminal autonomic cephalalgia that, when refractory to medical treatment, can be treated with Gamma Knife radiosurgery (GKRS). The outcomes of studies investigating GKRS for CH in the literature are inconsistent, and the ideal target and treatment parameters remain unclear. The aim of this systematic review is to evaluate the safety and the efficacy, both short and long term, of GKRS for the treatment of drug-resistant CH. A systematic review of the literature was performed to identify all clinical articles discussing GKRS for the treatment of CH. The literature review revealed 5 studies describing outcomes of GKRS for the treatment of CH for a total of 52 patients (48 included in the outcome analysis). The trigeminal nerve, the sphenopalatine ganglion, and a combination of both were treated in 34, 1, and 13 patients. The individual studies demonstrated initial meaningful pain reduction in 60-100% of patients, with an aggregate initial meaningful pain reduction in 37 patients (77%). This effect persisted in 20 patients (42%) at last follow-up. Trigeminal sensory disturbances were observed in 28 patients (58%) and deafferentation pain in 3 patients (6%). Information related to GKRS for CH are limited to few small open-label studies using heterogeneous operative techniques. In this setting, short-term pain reduction rates are high, whereas the long-term results are controversial. GKRS targeted on the trigeminal nerve or sphenopalatine ganglion is associated to a frequent risk of trigeminal disturbances and possibly deafferentation pain.

Long-term outcome of adjunctive Gamma Knife radiosurgery in skull-base chordomas and chondrosarcomas: An Indian experience

Skull-base chordomas (CD) and chondrosarcomas (CS) are locally-invasive tumors, have similar clinical presentations, while differing in their nature of growth and outcomes. In this study, we compare the long-term outcomes of Gamma Knife Radiosurgery (GKRS) as an adjunctive treatment modality for residual skull-base CD and CS. A retrospective analysis of clinico-radiological, pathological, radiotherapeutic and outcome data was carried out in patients who underwent adjunctive GKRS for residual skull-base CD and CS at P D Hinduja Hospital, Mumbai, between 1997 and 2020. All 27 patients included had either histopathologically proven CD (20 patients) or CS (7 patients). Brachyury immunohistochemistry in CD specimens gave 70.6% positivity. Total sessions of GKRS in CD and CS groups were 22 and 7, respectively. Mean tumor volume and mean margin dose in CD group were 6.53 ± 4.18 cm3 and 15.95 ± 1.49 Gy respectively, while for CS group, they were 4.16 ± 2.79 cm3 and 18.29 ± 3.15 Gy. With mean follow-up periods of 5.25 ± 4.73 years and 6 ± 2.07 years respectively, the CD and CS groups showed 5-year progression free survival (PFS) of 56.8% and 57.1%, and a 5-year overall survival (OS) of 82.1% and 100%. Sub-group analysis in both CD and CS groups revealed a better 5-year PFS with the following factors – CS histopathology, patient age < 45 years, margin dose > 16 Gy, tumor volume < 7 cm3 (p-value < 0.05), gross total resection, and brachyury positivity. Adjunctive radiotherapy for skull-base CD and CS holds promise.