Magnetic Resonance Imaging-Guided Stereotactic Body Radiation Therapy for Medically Inoperable Endometrial Cancer.

Endometrial carcinoma is the most frequently diagnosed gynecological cancer among women aged 50 and older in developed countries. In patients who are not amenable to surgery, radiotherapy results in improved survival with acceptable adverse effect profiles. Definitive stereotactic body radiotherapy (SBRT) as a monotherapy remains an unaddressed concept in the literature. Here, we present the case of an 86-year-old woman who was diagnosed with early-stage endometrial carcinoma and was medically inoperable due to cardiac comorbidities. She was treated with magnetic resonance imaging-guided online adaptive radiotherapy-based SBRT. She tolerated the treatment well, with mild increased vaginal discharge. Complete metabolic and radiological responses were obtained. She continues to be disease free in the first year of treatment with no long-term side effects. Our protocol presents promising results with a safe toxicity profile for inoperable early-stage endometrial cancer. Future studies are warranted in light of the current knowledge.

Efficacy of whole-sellar gamma knife radiosurgery for magnetic resonance imaging-negative Cushing's disease.

BACKGROUND: Corticotroph adenoma delineation in Cushing's disease (CD) patients with previous surgery can be challenging. This study investigated the outcome of whole-sellar gamma knife radiosurgery (GKRS) in MRI-negative, but hormone-active CD patients with prior failed treatment attempts. METHODS: We retrospectively analyzed data of nine CD cases who underwent whole-sellar GKRS between April 2008 and April 2020 at a single center. Remission was determined as normal morning serum cortisol, normal 24-hour urinary free cortisol (UFC) or extended postoperative requirement for hydrocortisone replacement. RESULTS: Median age was 35.0 years, and most of the cases were female (89%). All subjects had undergone previous surgery. The mean pre-GKRS morning serum cortisol and 24-hour UFC were 27.5 µg/dL and 408.0 µg, respectively. Target volume varied from 0.6 to 1.8 cc, and the median margin dose was 28 Gy. The median duration of endocrine follow-up was 105 months, and initial endocrine remission was achieved in eight subjects (89%) at a median time of 22 months. The actuarial initial remission was 44% at two years, 67% at four years, and 89% at six years. The mean recurrence-free survival was 128 months. Age and pre-GKRS morning serum cortisol was found to be predictors for initial and durable endocrine remissions. New-onset hypopituitarism was observed in two of five patients (40%). None of the patients developed new neurological deficits and had GKRS-related adverse events during the follow-up. CONCLUSIONS: Whole-sellar GKRS is a safe and efficient method to manage MRI-negative CD and provides similar GKRS outcome rates as in MRI-positive CD.

The effect of tumor shape irregularity on Gamma Knife treatment plan quality and treatment outcome: an analysis of 234 vestibular schwannomas.

The primary aim of Gamma Knife (GK) radiosurgery is to deliver high-dose radiation precisely to a target while conforming to the target shape. In this study, the effects of tumor shape irregularity (TSI) on GK dose-plan quality and treatment outcomes were analyzed in 234 vestibular schwannomas. TSI was quantified using seven different metrics including volumetric index of sphericity (VioS). GK treatment plans were created on a single GK-Perfexion/ICON platform. The plan quality was measured using selectivity index (SI), gradient index (GI), Paddick's conformity index (PCI), and efficiency index (EI). Correlation and linear regression analyses were conducted between shape irregularity features and dose plan indices. Machine learning was employed to identify the shape feature that predicted dose plan quality most effectively. The treatment outcome analysis including tumor growth control and serviceable hearing preservation at 2 years, were conducted using Cox regression analyses. All TSI features correlated significantly with the dose plan indices (P < 0.0012). With increasing tumor volume, vestibular schwannomas became more spherical (P < 0.05) and the dose plan indices varied significantly between tumor volume subgroups (P < 0.001 and P < 0.01). VioS was the most effective predictor of GK indices (P < 0.001) and we obtained 89.36% accuracy (79.17% sensitivity and 100% specificity) for predicting PCI. Our results indicated that TSI had significant effects on the plan quality however did not adversely affect treatment outcomes.

Prostate-specific antigen nadir within 1 year of radiotherapy combined with hormone therapy predicts cancer-specific mortality and biochemical recurrence-free survival in prostate cancer patients.

BACKGROUND: In this study, we investigated the ability of prostate-specific antigen (PSA) 12 months after (nPSA12) external beam radiotherapy (EBRT) combined with androgen deprivation therapy (ADT) to predict biochemical recurrence-free survival (BRFS), overall survival (OS), and prostate cancer-specific mortality (PCSM) in intermediate- and high-risk prostate cancer patients. METHODS: We retrospectively reviewed the clinical data of 338 intermediate- and high-risk prostate cancer patients treated with EBRT with ADT at our institution between 2000 and 2018. The median radiation dose was 76 Gy, the median initial PSA level was 17 ng/mL (range, 1-228 ng/mL), and the median duration of ADT was 24 months (range, 6-167 months). The median PSA level 1 months after EBRT was 0.06 ng/mL (range, 0-25.6 ng/mL). Univariate and multivariate analyses were performed. Patient survival was assessed using the Kaplan-Meier method and Cox proportional hazards regression analyses. RESULTS: The median follow-up time was 5 years (range, 1-20 years). Multivariate analysis revealed that nPSA was an independent and significant factor associated with OS, PCSM, and BRFS (P = 0.008, P = 0.001, P = 0.04). Furthermore, the time to nPSA12 was an independent predictor of PCSM and BRFS (P = 0.042, P = 0.021). Pelvic irradiation was also significantly associated with worse OS and PCSM (P = 0.004, P = 0.01). Additionally, age (≤ 70 or > 70 years) and hormone therapy duration (6 months, 1-3 years, or > 3 years) were significantly associated with OS and PCSM, respectively (P = 0.004, P = 0.02). For high risk, nPSA and nPSA12 were an independent predictor for BRFS. (P = 0.021, P = 0.029) CONCLUSION: The nPSA12 level of > 0.06 ng/mL may independently predict worse PCSM and BRFS in intermediate- and high-risk prostate cancer patients undergoing EBRT and ADT. Additionally, for high risk, nPSA > 0.06 ng/mL and nPSA12 > 0.06 ng/mL may independently predict worse BRFS.

Dosimetric evaluation of VMAT and helical tomotherapy techniques comparing conventional volumes with clinical target volumes based on new ESTRO ACROP post-mastectomy with immediate implant reconstruction contouring guidelines.

BACKGROUND: The ESTRO-ACROP Consensus Guideline (EACG) recommends implant excluded clinical target volume (CTVp) definitions for post-mastectomy radiation therapy after implant-based immediate breast reconstruction (IBR). The purpose of this study is to investigate the effectiveness of Helical Tomotherapy (HTp) and Volumetric Modulated Arc Therapy (VMATp) treatment techniques in terms of CTVp coverage and reduced organ at risk (OAR), normal tissue and implant doses when CTVp was used for treatment planning as the target structure instead of conventional CTV. METHODS: Eight left-sided and eight right-sided breast cancer patients who underwent IBR after mastectomy were included in this study. Planning CT data sets were acquired during free breathing and patients were treated with HT technique targeted to conventional CTV. Retrospectively, CTVp was delineated based on EACG by the same radiation oncologist, and treatment plans with HTp and VMATp techniques were generated based on CTVp. For each patient, relevant dosimetric parameters were obtained from three different treatment plans. RESULTS: There was no statistically significant difference on target coverage in terms of, PTVp-D95, PTVp-Vpres, homogeneity index (p > 0.05) between HTp and VMATp plans. But, the conformity numbers were significantly higher (HTp vs VMATp, 0.69 ± 0.15 vs 0.79 ± 0.12) for VMATp (Z = - 2.17, p = 0.030). While HTp significantly lowered Dmax and Dmean for LAD (LAD-Dmax: χ2 = 12.25, p = 0.002 and LAD-Dmean: χ2 = 12.30, p = 0.002), neither HTp nor VMATp could reduce maximum and mean dose to heart (p > 0.05). Furthermore, heart volume receiving 5 Gy was significantly higher for VMATp when compared to HTp (21.2 ± 9.8 vs 42.7 ± 24.8, p: 0.004). Both techniques succeeded in reducing the mean dose to implant (HTp vs HT, p < 0.001; VMATp vs HT, p < 0.001; VMATp vs HTp, p = 0.005). CONCLUSION: Both HTp and VMATp techniques succeeded to obtain conformal and homogeneous dose distributions within CTVp while reducing the mean implant dose. HTp was found to be superior to VMATp with regards to lowering all OAR doses except for CB.

Limited field adaptive radiotherapy for glioblastoma: changes in target volume and organ at risk doses.

OBJECTIVE: This study aimed to investigate the tumor volume changes occurring during limited-field radiotherapy (RT) for glioblastoma patients and whether a volume-adapted boost planning approach provided any benefit on tumor coverage and normal tissue sparing. MATERIALS AND METHODS: Twenty-four patients underwent simulation with magnetic resonance (MR) and computed tomography (CT) scans prior to RT (MR_initial, CT_initial) and boost treatment (MR_adapt, CT_adapt). For the boost phase, MR_initial and MR_adapt images were used to delineate GTV2 and GTV2_adapt, respectively. An initial boost plan (Plan_initial) created on CT_initial for PTV2 was then reoptimized on CT_adapt by keeping the same optimization and normalization values. Plan_adapt was generated on CT_adapt for PTV2_adapt volume. Dose volume histogram parameters for target volumes and organs-at-risk were compared using these boost plans generated on CT_adapt. Plan_initial and Plan_adaptive boost plans were summed with the first phase plan and the effect on the total dose was investigated. RESULTS: Target volume expansion was noted in 21% of patients while 79% had shrinkage. The average difference for the initial and adaptive gross tumor volume (GTV), clinical target volume (CTV), and planning target volume (PTV) volumes were statistically significant. Maximum dose differences for brainstem and optic chiasm were significant. Healthy brain tissue V10 and ipsilateral optic nerve maximum doses were found to decrease significantly in Plan_adaptive. CONCLUSION: Results of this study confirm occurrence of target volume changes during RT for glioblastoma patients. An adaptive plan can provide better normal tissue sparing for patients with lesion shrinkage and avoid undercoverage of treatment volumes in case of target volume expansion especially when limited-fields are used.

Hormonal and radiologic outcomes after gamma knife radiosurgery for nonfunctioning pituitary adenomas.

BACKGROUND: Gamma knife radiosurgery (GKRS) is an established treatment option for residual and recurrent nonfunctioning pituitary adenoma (NFPA). This investigation assessed hormonal and radiologic outcomes after adjuvant and primary GKRS for NFPAs. METHODS: This retrospective study included 252 patients with NFPA who underwent GKRS at a single center between 2005 and 2016. GKRS was performed as adjuvant procedure in 216 (85.8%) patients and as primary procedure in 36 (14.2%) patients. Characteristics of these two groups were compared. RESULTS: Mean age was comparable between adjuvant and primary GKRS groups (48.3 ± 12.6 vs. 52.2 ± 13.2 years, respectively, p > 0.05). Adjuvant GKRS and primary GKRS groups were similar in terms of the mean prescribed radiation dose and tumor volume (15.1 ± 2.7 vs. 15.3 ± 1.9 Gy and 4.2 ± 3.6 vs. 3.1 ± 2.5 cm3, respectively, p > 0.05 for both). The rate of endocrine deficiency during 5-year follow-up showed similar trend in adjuvant and primary GKRS groups (3.7%, 8.7%, and 14.8% vs. 5.6%, 13.9%, and 27.8% at first, third, and fifth year time points, respectively). Tumor control rates were also similar (98.6%, 96.3%, and 93% vs. 100%, 97.3%, and 94.5% at first, third, and fifth year time points, respectively). In both groups, tumor volume >5 cm3 was associated with higher rate of hypopituitarism and tumor progression. CONCLUSIONS: GKRS was effective both as adjuvant and primary procedure in patients with NFPA. Radiation dose of ≤13.5 Gy was associated with lower tumor control rate and tumor volume >5 cm3 was associated with higher rates of hypopituitarism and tumor progression.

Stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic patients: initial clinical experience.

PURPOSE: We aimed to present our initial clinical experience on the implementation of a stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic disease. MATERIALS AND METHODS: Twenty-one patients (24 lesions) with liver metastasis treated with SMART were included in this retrospective study. Step-and-shoot intensity-modulated radiotherapy technique was used with daily plan adaptation. During delivery, real-time imaging was used by acquiring planar magnetic resonance images in sagittal plane for monitoring and gating. Acute and late toxicities were recorded both during treatment and follow-up visits. RESULTS: The median follow-up time was 11.6 months (range, 2.2 to 24.6 months). The median delivered total dose was 50 Gy (range, 40 to 60 Gy); with a median fraction number of 5 (range, 3 to 8 fractions) and the median fraction dose was 10 Gy (range, 7.5 to 18 Gy). Ninety-three fractions (83.7%) among 111 fractions were re-optimized. No patients were lost to follow-up and all patients were alive except one at the time of analysis. All of the patients had either complete (80.9%) or partial (19.1%) response at irradiated sites. Estimated 1-year overall survival was 93.3%. Intrahepatic and extrahepatic progression-free survival was 89.7% and 73.5% at 1 year, respectively. There was no grade 3 or higher acute or late toxicities experienced during the treatment and follow-up course. CONCLUSION: SMART represents a new, noninvasive and effective alternative to current ablative radiotherapy methods for treatment of liver metastases in oligometastatic disease with the advantages of better visualization of soft tissue, real-time tumor tracking and potentially reduced toxicity to organs at risk.

Gamma knife radiosurgery for high-risk lactotroph adenomas: Long-term results.

Gamma Knife radiosurgery (GKRS) for lactotroph adenomas (LAs) or prolactinomas is limited due to the effectiveness of medical treatments and surgery. Cases who are refractory to medical treatment and/or surgery may be managed with GKRS. We aimed to describe the effectiveness of GKRS for high-risk lactotroph adenomas (HRLAs) and LAs that were medically and surgically refractory. We analyzed our series of patients with HRLAs and LAs who were managed with GKRS following failed medical treatment and surgery and who had at least three years of follow-up. A total of 52 patients (22 HRLAs and 30 LAs) were included in the analysis of radiological, endocrine, and clinical outcomes. Radiological control was achieved in 68.2% of subjects in the HRLA group and 96.7% of subjects in the LA group. Hormonal control was achieved in 68.2% of patients in the HRLA group and 80% of patients in the LA group. On univariate analysis, hormonal control was significantly associated with pre-treatment volume (p = 0.007), higher margin dose (p = 0.002) and Ki-67 proliferative index (p = 0.007). Complications involved new pituitary hormone deficiencies in 19.2% of patients and asymptomatic peripheral visual field defect in 1.9% of patients. To the best of our knowledge, this is the first study to examine the effectiveness of GKRS in LAs and HRLAs, with the highest median follow-up in the literature. High hormonal control rate, even in HRLAs, and lower complication rates suggest that GKRS should be part of the techniques for managing treatment refractory LAs.

Magnetic resonance image-guided adaptive stereotactic body radiotherapy for prostate cancer: preliminary results of outcome and toxicity.

OBJECTIVE: Using moderate or ultra-hypofractionation, which is also known as stereotactic body radiotherapy (SBRT) for treatment of localized prostate cancer patients has been increased. We present our preliminary results on the clinical utilization of MRI-guided adaptive radiotherapy (MRgRT) for prostate cancer patients with the workflow, dosimetric parameters, toxicities and prostate-specific antigen (PSA) response. METHODS: 50 prostate cancer patients treated with ultra-hypofractionation were included in the study. Treatment was performed with intensity-modulated radiation therapy (step and shoot) technique and daily plan adaptation using MRgRT. The SBRT consisted of 36.25 Gy in 5 fractions with a 7.25 Gy fraction size. The time for workflow steps was documented. Patients were followed for the acute and late toxicities and PSA response. RESULTS: The median follow-up for our cohort was 10 months (range between 3 and 29 months). The median age was 73.5 years (range between 50 and 84 years). MRgRT was well tolerated by all patients. Acute genitourinary (GU) toxicity rate of Grade 1 and Grade 2 was 28 and 36%, respectively. Only 6% of patients had acute Grade 1 gastrointestinal (GI) toxicity and there was no Grade ≥ 2 GI toxicity. To date, late Grade 1 GU toxicity was experienced by 24% of patients, 2% of patients experienced Grade 2 GU toxicity and 6% of patients reported Grade 2 GI toxicity. Due to the short follow-up, PSA nadir has not been reached yet in our cohort. CONCLUSION: In conclusion, MRgRT represents a new method for delivering SBRT with markerless soft tissue visualization, online adaptive planning and real-time tracking. Our study suggests that ultra-hypofractionation has an acceptable acute and very low late toxicity profile. ADVANCES IN KNOWLEDGE: MRgRT represents a new markerless method for delivering SBRT for localized prostate cancer providing online adaptive planning and real-time tracking and acute and late toxicity profile is acceptable.

Long-term results of gamma knife radiosurgery for foramen magnum meningiomas.

Outcomes of 37 patients of foramen magnum meningioma (FMM) were evaluated, and the related literature was reviewed to determine the efficacy of Gamma Knife radiosurgery (GKRS) for treating patients with FMM. We present the largest series reported from a single institution with the longest follow-up to date. The database of patients who underwent GKRS for FMM between 2007 and 2019 was evaluated retrospectively. A total of 37 patients with radiological and pathological features consistent with FMM were included in this series. Thirty-three patients were female, and 4 were male. The median age was 58 years (range, 23-74 years). The most common symptom at diagnosis was headache (64.9%). Twelve patients had a history of microsurgical resection. The median duration from the initial onset of symptoms to GKRS was 12 months (range 1-140 months). Among the 37 tumors, eight (21.6%) were located ventrally, 24 (64.9%) laterally, and five (13.5%) dorsally. The median target volume was 3.30 cm3 (range, 0.6-17.6 cm3). Thirty-five patients (95%) were treated with single fraction GKRS, and two patients (5%) were treated with hypofractionated GKRS. The median clinical follow-up was 80 months (range, 18-151 months), while the median radiological follow-up was 84 months (range, 18-144 months). At the last clinical follow-up after GKRS, 27 patients (73%) had improved symptoms, and none had worsened pre-GKRS symptoms. At the last radiological follow-up after GKRS, 23 tumors (62.2%) remained stable, 13 (35.1%) decreased in size, and 1 (2.7%) increased in size. Tumor control, including stable and regressed tumors, was achieved in 97.3% of patients. Our cohort demonstrates that GKRS is an effective and safe treatment for patients with either primary or recurrent/residual FMM.

Lymph node ratio as an independent prognostic factor for breast cancer-related mortality in patients with node-positive breast cancer.

AIM: This study assessed whether prognostic information could be obtained in patients with lymph node (LN)-positive breast cancer based on their LN ratios (LNRs) and explored the relationships between other potential prognostic factors and survival. SETTING AND DESIGN: This was a retrospective clinical study. MATERIALS AND METHODS: This study included 608 women with node-positive nonmetastatic breast cancer. Clinical and pathologic data were retrospectively evaluated. The median age was 51 years (range: 23-84 years). All patients received adjuvant radiotherapy after radical surgery. A total dose of 50 Gy was administered to the chest wall or breast and LN regions with 2 Gy daily fractions. A 10-Gy boost was administered to the breast tumor bed. The cutoff value of LNR was defined as low risk (<0.21) in 278 patients, intermediate risk (0.21-0.65) in 217 patients, and high risk (>0.65) in 113 patients. Prognostic variables included patient characteristics, disease characteristics, and interventional factors. The primary endpoint was overall survival and the secondary endpoint was breast cancer-related mortality. STATISTICAL ANALYSIS USED: Statistical analyses were performed using the Kaplan-Meier method, log-rank test, and Cox regression analysis. P value was required to be <0.05. RESULTS: Within a median follow-up period of 95.4 months (range: 5-232.4 months), overall survival rates for 10 and 15 years were 66% and 53%, respectively. Multivariate analysis revealed that LNR (P = 0.026), estrogen receptor status (ERS) (P = 0.021), age (P = 0.04), and smoking (P = 0.024) were independent significant prognostic factors for overall survival. Breast cancer-related mortality rates at 10 and 15 years were 70.7% and 60%, respectively. LNR (P = 0.03) and ERS (P = 0.002) were independent significant prognostic factors for breast cancer-related mortality. CONCLUSIONS: LNR and ERS were significant prognostic factors for survival at all endpoints.

Efficacy of gamma knife radiosurgery in the treatment of intraventricular meningiomas.

Intraventricular meningiomas (IVMs) are notably limited tumors and express one of the most challenging tumors in neurosurgery. Gamma Knife radiosurgery (GKRS) as an alternative for IVMs has been reported only in a few case series. We aimed to present six patients with IVMs who were treated with GKRS and do a literature review. The data of patients were retrospectively reviewed. All patients underwent a single session of GKRS with a median marginal dose of 12 Gy (range, 11-13). Target volume ranged from 1.2 to 9.5 cc. Routine imaging with contrast-enhanced MRI scans was performed every six months initially and thereafter yearly. New neurological deficits and symptoms stated or observed during follow-up were recorded and investigated. The mean age was 41.3 years (range, 30-71). GKRS was used as a primary treatment in five patients and as adjunctive treatment in one patient. The most common presenting symptom was a headache. The median duration of symptoms was 30 months (range, 5-240). Four tumors (67%) were located in the left lateral ventricle, and two were in the right lateral ventricle. During a median follow-up of 71.5 months (range, 23-139), tumor volume was noted to have shrunk (median = 59.6%) in all patients (100%). One patient experienced post-GKRS peritumoral edema that resolved after a short course of steroids. The mean progression-free survival was 117.5 months (95% CI, 81-154 months). Neurologic symptoms and signs improved in all patients. GKRS may be a feasible treatment alternative in patients with small IVMs with low morbidity.

Gamma knife radiosurgery in patients with Cushing's disease: Comparison of aggressive pituitary corticotroph tumor versus corticotroph adenoma.

Aggressive pituitary corticotroph tumors causing Cushing's disease are rare, and there is limited data about their clinical management. Here, we aimed to report our long-term experience with gamma knife radiosurgery (GKRS) as adjuvant treatment in patients with residual or recurrent pituitary corticotroph tumors. This retrospective study included 45 adult patients (M/F, 7/38; mean age, 40.2 ±â€¯13.1 years) with residual tumor or recurrence after initially successful surgical resection. Single-session GKRS was performed in all patients. Tumors with a Ki-67 value higher than 3 % and radiologic invasion to surrounding tissues were classified as aggressive tumor group. Clinical, hormonal and radiological findings were compared between the aggressive (n = 10) and non-aggressive adenoma (n = 35) groups. Following GKRS, tumor volumes were significantly reduced in both groups. The mean time to hormonal remission in the non-aggressive group was significantly shorter than in the aggressive group (23.5 ±â€¯6.3 vs 33.0 ±â€¯5.0 month, respectively, p < 0.05). New-onset hypopituitarism was identified in only seven patients (15 %) after GKRS in the whole cohort. The present study introduces several essential findings about aggressive corticotroph tumors. First, aggressive behavior tends to occur more frequently in male subjects. Second, time to GKRS was significantly shorter in the aggressive group. Moreover, a tumor volume ≥2 cm3 may be associated with clinical aggressiveness in corticotroph tumors. In conclusion, we suggest that early adjuvant GKRS is an effective treatment option in aggressive pituitary corticotroph tumors.

Prognostic factors in medically inoperable early stage lung cancer patients treated with stereotactic ablative radiation therapy (SABR): Turkish Radiation Oncology Society Multicentric Study.

OBJECTIVE: We identified factors influencing outcomes in patients with medically inoperable early stage lung cancer (MIESLC) treated with stereotactic ablative radiation therapy (SABR) at 14 centers in Turkey. MATERIALS AND METHODS: We retrospectively analyzed 431 patients with stage I-II MIESLC treated with SABR from 2009 through 2017. Age; sex; performance score; imaging technique; tumor histology and size; disease stage radiation dose, fraction and biologically effective dose with an α/ß ratio of 10 (BED10 ); tumor location and treatment center were evaluated for associations with overall survival (OS), local control (LC) and toxicity. RESULTS: Median follow-up time was 27 months (range 1-115); median SABR dose was 54 Gy (range 30-70) given in a median three fractions (range 1-10); median BED10 was 151 Gy (range 48-180). Tumors were peripheral in 285 patients (66.1%), central in 69 (16%) and <1 cm from mediastinal structures in 77 (17.9%). Response was evaluated with PET/CT in most cases at a median 3 months after SABR. Response rates were: 48% complete, 36.7% partial, 7.9% stable and 7.4% progression. LC rates were 97.1% at 1 year, 92.6% at 2 years and 91.2% at 3 years; corresponding OS rates were 92.6%, 80.6% and 72.7%. On multivariate analysis, BED10 > 100 Gy (P = .011), adenocarcinoma (P = .025) and complete response on first evaluation (P = .007) predicted favorable LC. BED10 > 120 Gy (hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.1-3.2, P = .019) and tumor size (<2 cm HR 1.9, 95% CI 1.3-3, P = .003) predicted favorable OS. No grade 4-5 acute side effects were observed; late effects were grade ≤3 pneumonitis (18 [4.2%]), chest wall pain (11 [2.5%]) and rib fracture (1 [0.2%]). CONCLUSION: SABR produced encouraging results, with satisfactory LC and OS and minimal toxicity. BED10 > 120 Gy was needed for better LC and OS for large, non-adenocarcinoma tumors.

Long-term results of Gamma Knife radiosurgery for facial nerve schwannomas.

OBJECTIVE: Long-term outcomes of eleven cases of facial nerve schwannoma were evaluated and the related literature was reviewed to determine the efficacy of Gamma Knife radiosurgery for treating patients with facial nerve schwannoma. METHODS: Eleven patients with facial nerve schwannoma (7 women and 4 men; mean age, 44.2 years; range, 19-73 years) underwent Gamma Knife radiosurgery. The most common symptoms were facial palsy (n = 10) and hearing loss (n = 7). Five patients presented with headache. Two patients had undergone prior resection. The patients' clinical and radiographic data were evaluated retrospectively. RESULTS: For the 11 cases of facial nerve schwannoma, mean tumor volume was 3.1 cm3 (range, 0.4-7.4 cm3) and the mean marginal dose applied was 11.9 Gy (range, 11-13 Gy). The mean follow-up period was 84.3 months (range, 66-117 months). Tumor control was achieved in all patients. At the time of writing, four patients experienced tumor volume regression and the other seven were in stable condition. During follow-up, nine patients experienced no change in their facial function, two experienced deteriorated facial function, and none developed new facial palsy. Ten patients who had serviceable hearing prior to Gamma Knife radiosurgery retained their hearing. CONCLUSIONS: Gamma Knife radiosurgery achieves excellent results with respect to tumor control for 7 years on average. In addition, Gamma Knife radiosurgery provides good results in facial nerve and hearing function at long term. Our series demonstrates that Gamma Knife radiosurgery is an effective and safe treatment for patients with either primary or residual facial nerve schwannoma.

Efficacy and Safety of Gamma Ventral Capsulotomy for Treatment-Resistant Obsessive-Compulsive Disorder: A Single-Center Experience.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a chronic disease with a lifetime prevalence of 3% and is associated with severe impairment in familial and socio-occupational functioning. Gamma ventral capsulotomy (GVC) is a treatment choice in carefully chosen patients, with few published reports. In this study, we aimed to report the efficacy and safety of GVC in 21 patients with treatment-resistant OCD. METHODS: This is a retrospective single-center study. Twenty-one patients meeting the selection criteria were included. Patients were considered responders if there were ≥35% reduction in post-GVC Yale-Brown Obsessive Compulsive Scale scores and considered in remission if scores were ≤8. The mean and median clinical follow-up durations were 60.7 and 56 months, respectively (range, 38-149 months). RESULTS: The mean baseline Yale-Brown Obsessive Compulsive Scale score of 35.7 (n = 21) decreased to 15.3 (n = 20) at 36 months follow-up evaluation (P < 0.0001). Fifteen patients (75%) achieved a full response. Of those patients, 7 (35%) were considered to be in remission. There were no partial responders, and 5 patients (25%) were classified as nonresponders. The pre-GVC mean Beck Depression Inventory-II score of 35.1 (n = 21) decreased to 13.8 (n = 20) at 36 months follow-up evaluation (P < 0.0001). Three patients (14.3%) had a transient post-GVC headache that resolved within a week, and 2 patients (9.5%) had persistent headaches that responded to 2-week oral corticosteroid treatment. A brain cyst developed after GVC in 2 patients (10%). No clinically notable abnormalities were seen on neurologic examination at any follow-up. CONCLUSIONS: Gamma ventral capsulotomy is a reasonable treatment method in select patients with treatment-resistant OCD.

Gamma Knife Radiosurgery for Anterior Clinoid Process Meningiomas: A Series of 61 Consecutive Patients.

OBJECTIVE: Gamma Knife radiosurgery (GKRS) outcomes for anterior clinoid process (ACP) meningiomas have not been specifically reported within any meningioma series. We present the initial and largest series in the literature that describes the presenting features, radiosurgery parameters, and radiologic and long-term clinical outcomes for 61 patients with ACP meningiomas treated with GKRS. METHODS: Medical records were reviewed for 61 consecutive patients at a single center who underwent GKRS for ACP meningioma between 2008 and 2016. RESULTS: Of 61 patients with ACP meningiomas, 49 (80%) were treated with GKRS as primary treatment, and 12 (20%) were treated with GKRS as an adjuvant therapy. Before GKRS, 29 patients presented with visual impairment and 50 patients presented with headache. Median patient age was 54.9 years. Median tumor volume was 3.2 cm3, and median margin dose was 12.0 Gy. The median radiologic follow-up time after GKRS was 75 months. During follow-up, tumor volume regressed in 37 cases (61%) and remained unchanged in 24 cases (39%). None of the patients experienced tumor volume progression. Tumor volume <3 cm3 was an independent predictor of tumor volume regression after GKRS (univariate analysis, P = 0.047; multivariate analysis, P = 0.049). Of 29 patients who presented with visual impairment, 16 (55%) improved after GKRS. None of the 61 patients developed new neurologic deficits after GKRS. CONCLUSIONS: GKRS provides a high rate of tumor volume control for ACP meningiomas as well as a low complication rate. Excellent tumor volume control was associated with smaller tumor size only.

Gamma knife radiosurgery for pituitary spindle cell oncocytomas.

OBJECTIVES: Spindle cell oncocytomas (SCOs) are benign lesions of the posterior portion of the pituitary gland that typically come to neurosurgical attention due to compression of the sellar or parasellar structures, and headaches. Initial treatment options for SCOs include surgical resection, particularly via the transsphenoidal approach. However, given that initial resection tends to be insufficient and subsequent revision surgery carries high complication risk, adjuvant treatment modalities may appear to offer promising solutions for controlling tumor progression. This report focuses on a potential new therapeutic option for SCOs, gamma knife radiosurgery (GKRS). PATIENTS AND METHODS: The authors identified all patients at one center who had a pituitary lesion treated with GKRS between 2005 and 2016. Five patients with histopathologically confirmed SCO who underwent GKRS were retrospectively identified and included in the present study RESULTS: The mean patient age was 52 years (range, 41-61 years). The most common presenting symptom was visual disturbance. All five patients had a history of transsphenoidal surgical resection prior to GKRS therapy. The mean tumor volume was 2.25 cm3 (range 0.7-5.38 cm3). The median tumor margin dose was 12 Gy (range, 12-14 Gy), and the median maximal dose was 24 Gy (range, 24-35 Gy). The median isodose was 50 (range, 40-50). No tumor volume progression was observed during radiological follow-up after GKRS (mean, 52 months; range, 36-84 months). At last follow-up, no neurological, endocrinological, or visual complications had been observed. CONCLUSION: Given their highly vascular and adherent nature, SCOs can be challenging tumors to treat, in particular when they recur. In our five cases, GKRS provided excellent tumor volume control for approximately 4.3 years on average. These results suggest that GKRS is a safe and effective treatment modality for histopathologically confirmed residual SCO.

Gamma Knife Radiosurgery for Hemorrhagic Brainstem Cavernomas.

AIM: To assess treatment results of gamma knife radiosurgery (GKRS) for hemorrhagic brainstem cavernous malformations (BSCMs). MATERIAL AND METHODS: A retrospective review of patients with hemorrhagic BSCMs, who were treated at the Acibadem Kozyatagi Hospital GKRS unit from May 2007 to October 2015 was performed. RESULTS: In total, 82 patients were identified. All patients had experienced at least one hemorrhagic event (range 1-3), and all of them presented with radiological evidence of hemorrhage. The median target volume was 0.3 ml, and the median marginal radiation dose was 12 Gy. The mean durations before and after surgery were 25.5 (range 1-204) months, and 50.3 (range 13-113) months, respectively. Pre-treatment hemorrhage rates were calculated from the date of first hemorrhage to the date of radiosurgery. There were 97 bleeds over 174.4 patient-years during the observation period, with an annual hemorrhage rate of 55.7%. If the first bleed is excluded, the annual hemorrhage rate was 8.6%. Only three patients demonstrated re-bleeding, which occurred at 3, 12 and 79 months after radiosurgery. Over a total follow up time of 344 patient-years the annual re-bleeding rate was therefore 0.87%, indicating that the risk of BSCM hemorrhage was significantly decreased by radiosurgery. CONCLUSION: GKRS was a safe and effective treatment for symptomatic low volume BSCMs when a low marginal dose is used. A randomized controlled trial is needed that compares GKRS to observation if we want to establish the true efficacy of this treatment.