Multiple Brain Metastases Research Articles

P16.07.B PROSPECTIVE DOUBLE ARM PHASE 2 RANDOMIZED TRIAL FOR PATIENTS WITH MULTIPLE BRAIN METASTASIS AND/OR LEPTOMENINGEAL CARCINOMATOSIS: COMPARISON OF WHOLE BRAIN RADIATION THERAPY (WBRT) ALONE AND WBRT PLUS SILIBININ

Abstract BACKGROUND Occurrence of brain metastases (BMs) is increasing given availability of Magnetic Resonance Imaging (MRI) able to detect also small brain lesions, and most effective systemic therapy able to better control extra-cranial disease. Estimated 20% of patients with cancer will develop BMs. In case of limited brain metastases, radiosurgery or hypofractionated radiosurgery is treatment of choice. A subgroup of patients characterized by extensive brain disease and/or leptomeningeal carcinomatosis can require whole brain radiotherapy (WBRT). Since the 1950s, WBRT has been the most treatment used for patients with multiple BMs, given its effectiveness in palliation, widespread availability, and ease to deliver. However, the median overall survival (OS) recorded is restricted to 3 months, on the average. A better understanding of molecular and cellular mechanisms underlying brain metastasis might be expected to lead of improvements in overall survival. Recent studies demonstrated that active signal transducer and activator of transcription 3 (STAT3) in reactive astrocytes correlates with reduced survival from diagnosis of intracranial metastases. Blocking STAT3 signaling in reactive astrocytes reduces experimental brain metastasis, even at advanced stages of colonization. Silibinin is a natural polyphenolic flavonoid isolated from seed extracts of herb milk thistle. It has been shown to impair STAT3 activation, and in preclinical studies, show an anticancer effects in vitro and in vivo. Based on this background, we designed a double arm phase 2 randomized trial evaluating the benefit of Silibinin associated to WBRT respect to WBRT alone. Primary endpoint is OS, secondary endpoints are toxicity in term of corticosteroid therapy use, brain failure (BF) and progression free survival (PFS). MATERIAL AND METHODS Forty-four patients will be enrolled in two years. Patients with histological or cytological confirmation of solid tumor malignancy, clinical indication for WBRT and Karnofsky performance status (KPS) ≥60 will be enrolled. In arm A experimental, WBRT is concomitant to Silibinin, in arm B control, WBRT alone will be administered. In both arms, total dose of radiotherapy is 30 Gy in 10 fractions. Quality of life and use of corticosteroids will be evaluated first, last day of RT, and during follow-up. Outcome will be evaluated by MRI or CT at 2 months after RT, and every 3 months thereafter. RESULTS From March 2023, 6 patients were enrolled, 2 patients in Arm A and 4 in arm B. Primary histology was breast cancer in 3 patients and non small cell lung cancer in 3. In arm A, 1 patients dismissed RT for worsening of general conditions related to rapid lung progression. CONCLUSION WBRT with or without Silibinin was well tolerated, no acute toxicities or increase of corticosteroids were observed.

P01.06.B EVOLUTION OF NEUROCOGNITIVE FUNCTIONING AFTER RADIOTHERAPY IN PATIENTS WITH BRAIN METASTASES

Abstract BACKGROUND Brain metastases (BMs) occur in ten to thirty percent of the adult population. They present a heterogeneous population, with almost half already experiencing cognitive impairment prior to brain radiotherapy (RT). While RT aims to improve or stabilize the neurologic deficit(s), neurocognitive decline is often reported after treatment. To better understand cognitive performance after RT, we assessed the individual cognitive performance before, three months and at least eleven months after RT. METHODS The study population consisted of 32 adult patients with BMs that were referred for brain RT. An elaborate battery of neuropsychological tests was used to assess objective cognitive performance. Additionally, the Cognitive Failures Questionnaire (CFQ) and a semi-structured interview measured subjective cognitive performance and the EORTC QLQ-C30 and EQ-5D-3L were used to assess quality of life (QoL). The reliable change index (RCI) as formulated by Maassen et al. (2009) represented clinically significant change in cognitive performance at the follow-up time points, whereby RCI <-1.645 was denoted decline and RCI >1.645 improvement. This RCI takes into account test-retest reliability and practice effects. RESULTS Three months post-RT, 83% of the patients showed declines in at least one cognitive domain, with declines most frequent in memory (58%) and processing speed (36%). On the other hand, improvements were also found, especially for attention (92%) and fine motor coordination (46%). 50-60% of patients showed further decline in cognitive performance at task-level from three to eleven month follow-up, while 40% of patients showed further improvement. Multinomial logistic regressions indicated that a higher number of BMs was predictive of declined cognitive performance three months post-RT, specifically regarding executive functioning, processing speed and fine motor coordination. Additionally, patients without symptoms at the moment of BMs diagnosis more often showed declines in processing speed. BMs growth and age were not related to cognitive change. The change in cognitive performance was not related to either subjective cognitive performance or self-reported QoL. CONCLUSION Using a stringent RCI, we found patients who benefited from RT, but also patients who showed a clinical relevant cognitive decline three months post-RT. In most patients, this trend continued until at least eleven months after RT. Patients with multiple brain metastases may be particularly vulnerable to cognitive decline and death caused by tumour growth. However, life-extending RT also has its costs and thus requires careful consideration in shared decision-making regarding treatment options. GRANT INFORMATION The APRICOT study described in the current abstract as well as EG, were supported by funding from the Dutch Cancer Society “Koningin Wilhelmina Fonds (KWF)” (#11110).

Propensity score-matched analysis comparing hippocampus-avoidance whole-brain radiotherapy plus simultaneous integrated boost with hippocampus‑avoidance whole-brain radiotherapy alone for multiple brain metastases-a retrospective study in multiple institutions

BackgroundThe optimal treatment for multiple brain metastases has been recently controversially discussed.This study was aimed to explore the feasibility of Hippocampus-Avoidance Whole-Brain Radiotherapy plus a simultaneous integrated boost (HA-WBRT + SIB) in patients with multiple brain metastases and assess tumor control in comparison with Hippocampus-Avoidance Whole-Brain Radiotherapy (HA-WBRT) alone for brain metastases.MethodsIn this study, 63 patients with multiple brain metastases (≥ 4 metastases) had undergone HA-WBRT + SIB between January 2016 and December 2020 in the observation group:HA-WBRT (30 Gy in 12 fractions, the maximum dose of the hippocampus ≤ 14 Gy) plus a simultaneous integrated boost (48 Gy in 12 fractions) for brain metastases.Overall Survival (OS), Median survival,intracranial control (IC = control within the entire brain), intracranial progression-free survival (iPFS) and adverse events were compared with the control group (a HA-WBRT retrospective cohort) by propensity score matching analysis.ResultsAfter 1:1 propensity score matching,there were 56 patients in each group (the observation group, the control group). OS, median survival and iPFS were significantly longer in the observation group (18.4 vs. 10.9 months, P<0.001), (13.0 vs. 8.0 months, P<0.001), (13.9 vs.7.8 months, P<0.001). In comparison of 1-year-IC rates, the observation group also demonstrated higher than the control group (51.8% vs. 21.4%, P = 0.002), respectively. Seven hippocampal metastases were found in the control group (4/56,7.1%) and the observation group (3/56,5.4%) after HA-WBRT. The death rate of intracranial progression were 23.2% in the observation group and 37.5% in the control group.All adverse events were not significant difference between the two groups (P>0.05).ConclusionsHA-WBRT + SIB resulted in better OS,median survival, IC, iPFS, an acceptable risk of radiation response, and a potential way of declining neurocognitive adverse events, which may be a better treatment for patients with multiple brain metastases.

BSBM-11 COMBINING IMMUNOTHERAPY AND WHOLE-BRAIN RADIATION THERAPY IN A NOVEL SYNGENEIC LUNG CANCER BRAIN METASTASIS PRECLINICAL MODEL: DOES TIMING OF ADMINISTRATION MATTER?

Abstract Approximately 50% of all brain metastasis cases originate from primary lung tumors. Whole-brain radiation therapy (WBRT) is a common treatment for patients with multiple brain metastases, but patients rarely survive longer than one year after diagnosis. Recent studies demonstrate improved outcomes with combinatorial radiotherapy and immunotherapy, but the optimal timing of immunotherapy administration is unclear. Eliciting a robust immune response post-immunotherapy is vital for therapeutic efficacy. Our work shows that the BBB is disrupted and proinflammatory cytokines are increased in the brain 12 hours post-WBRT in immunocompetent but not immunocompromised mice. Additionally, efflux transporter activity is decreased at this time point. This study utilizes a novel Lewis Lung Carcinoma cell line, LLC-Br, which was developed in our laboratory to preferentially metastasize to the brain. Mice were treated with immune checkpoint inhibitors (ICIs) before or after WBRT then we evaluated tumor progression, survival, and blood-tumor barrier (BTB) permeability. We hypothesized administration of ICI following WBRT would increase survival, decrease tumor burden, and increase BTB permeability in our preclinical syngeneic lung cancer brain metastasis model.

The Redox-Active Manganese(III) Porphyrin, MnTnBuOE-2-PyP5+, Impairs the Migration and Invasion of Non-Small Cell Lung Cancer Cells, Either Alone or Combined with Cisplatin.

Manganese(III) porphyrin MnTnBuOE-2-PyP5+ (MnBuOE, BMX-001) is a third-generation redox-active cationic substituted pyridylporphyrin-based drug with a good safety/toxicity profile that has been studied in several types of cancer. It is currently in four phase I/II clinical trials on patients suffering from glioma, head and neck cancer, anal squamous cell carcinoma and multiple brain metastases. There is yet an insufficient understanding of the impact of MnBuOE on lung cancer. Therefore, this study aims to fill this gap by demonstrating the effects of MnBuOE on non-small cell lung cancer (NSCLC) A549 and H1975 cell lines. The cytotoxicity of MnBuOE alone or combined with cisplatin was evaluated by crystal violet (CV) and/or 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-Tetrazolium (MTS) reduction assays. Intracellular ROS levels were assessed using two fluorescent probes. Furthermore, the impact of MnBuOE alone or in combination with cisplatin on collective cell migration, individual chemotactic migration and chemoinvasion was assessed using the wound-healing and transwell assays. The expression of genes related to migration and invasion was assessed through RT-qPCR. While MnBuOE alone decreased H1975 cell viability at high concentrations, when combined with cisplatin it markedly reduced the viability of the more invasive H1975 cell line but not of A549 cell line. However, MnBuOE alone significantly decreased the migration of both cell lines. The anti-migratory effect was more pronounced when MnBuOE was combined with cisplatin. Finally, MnBuOE alone or combined with cisplatin significantly reduced cell invasion. MnBuOE alone or combined with cisplatin downregulated MMP2, MMP9, VIM, EGFR and VEGFA and upregulated CDH1 in both cell lines. Overall, our data demonstrate the anti-metastatic potential of MnBuOE for the treatment of NSCLC.

Reduced Mortality and Radiation Necrosis After Surgery With Postoperative Stereotactic Radiation in Patients With Multiple Brain Metastases.

Although stereotactic radiation has frequently supplanted whole-brain radiation therapy (WBRT) in treating patients with multiple brain metastases, the role of surgery for these patients remains unresolved. No randomized trials have compared surgical resection with postoperative stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) to SRS/SRT alone. Previous studies addressing surgery for patients with multiple brain metastases are often limited by small sample sizes, a lack of appropriate comparison groups, or a focus on patients treated before recent advances in targeted therapy and immunotherapy. We compared outcomes in patients with multiple brain metastases treated with surgical resection and postoperative SRS/SRT to those treated with SRS/SRT alone. We studied 734 patients with multiple newly diagnosed brain metastases (surgery with SRS/SRT, n = 228; SRS/SRT alone, n = 506) from 2011 to 2022 in a retrospective, single-institution cohort. Patients who received upfront whole-brain radiotherapy were excluded. Cox proportional hazards models were constructed for overall survival and additional intracranial outcomes. After adjustment for potential confounders, surgery with postoperative SRS/SRT was associated with decreased all-cause mortality compared with SRS/SRT alone (hazard ratio [HR]: 0.67, 95% CI [0.50-0.89], P = 5.56 × 10-3). The association between surgical resection and overall survival was replicated in a subset of the cohort after cardinality matching (HR: 0.64, 95% CI [0.46-0.88], P = 6.68 × 10-3). Patients with melanoma benefited significantly less from surgical resection compared with patients with other tumor types, most notably non-small-cell lung cancer. Compared with definitive SRS/SRT, cavity SRS/SRT was associated with a significantly reduced risk of both symptomatic radiation necrosis (HR: 0.22, 95% CI [0.08-0.59], P = 2.70 × 10-3) and radiographic radiation necrosis (HR: 0.23, 95% CI [0.09-0.57], P = 1.43 × 10-3) in multivariable models. In patients with multiple brain metastases, surgical resection before SRS/SRT is associated with reduced mortality and radiation necrosis. Prospective studies may further delineate patient populations that benefit from aggressive local, brain-directed treatment even with significant intracranial disease burden.

A sub-analysis of multi-center planning radiosurgery for intracranial metastases through automation (MC-PRIMA) comparing UK and international centers

A sub-analysis of the MC-PRIMA study was performed to compare the plan quality of stereotactic radiosurgery (SRS) to multiple brain metastases (MBM) between UK and other international centres. Six centres from the UK and nineteen from other international centres autoplanned using Multiple Brain Mets™ (AutoMBM; Brainlab, Munich, Germany) software for a five MBM study case from a prior planning competition that was originally organized by the Trans-Tasmania Radiation Oncology Group (TROG). Twenty-three dosimetric metrics and the resulting composite plan score per the TROG planning competition were compared between the UK and other international centres. Planning experience and planning time from each planner were recorded and statistically compared. Planning experiences between two groups are equal. Except for mean dose to the hippocampus, all other 22 dosimetric metrics were comparable between two groups. The inter-planner variations in these 23 dosimetric metrics and the composite plan score were also statistically equivalent. Planning time is slightly longer in the UK group (mean = 86.8 min) with a mean difference of 50.3 min. AutoMBM effectively achieves standardization of the plan quality of SRS to MBM within UK and further against the other international centres. Significant planning efficiency gain by AutoMBM both among the UK and other international centres may help to increase the capacity of SRS service by alleviating the clinical and technical loadings.

Comparison of Single and Multiple Treatment Plans Made in CyberKnife® Radiosurgery System on Phantom

While the use of CyberKnife® radiosurgery systems is increasing, the choice of treatment plan is also important. In this study, it was aimed to determine the more advantageous application by comparing the irradiation of all metastases at once and the protocols of irradiation of metastases separately in multiple brain metastases. For this, on an entirely new head phantom; 6 brain metastases and 3 critical organs, including the spinal cord, brain stem, and chiasm, were determined over the spaces where the dosimeters were placed. Computed tomography (CT) images of the head phantom were taken and these 6 tumors and 3 critical organs were drawn (contouring) on the image. In the treatment planning system, the dose we wanted to give was written and irradiation plans were created to be done separately with a single irradiation. Luminescence (OSL) dosimeters with BeO optical excitation were removed from the phantom after each irradiation and the count value obtained from the dosimeter reader device was recorded. Homogeneity index (HI), conformity index (CI), new conformity index (nCI), duration of treatment, and gradient index (GI) values of irradiation at one time and separately were compared. While it was found that irradiation of tumors with a separate treatment plan was more advantageous in terms of conformity index (CI), new conformity index (nCI), homogeneity index (HI), and coverage values, it was seen that a single plan was more suitable in terms of gradient index and duration.

Incurring detriments of unplanned readmission to the intensive care unit following surgery for brain metastasis

ObjectPostoperative intensive care unit (ICU) monitoring is a common regime after neurosurgical resection of brain metastasis (BM). In comparison, unplanned secondary readmission to the ICU after initial postoperative treatment course occurs in response to adverse events and might significantly impact patient prognosis. In the present study, we analyzed the potential prognostic implications of unplanned readmission to the ICU and aimed at identifying preoperatively collectable risk factors for the development of such adverse events.MethodsBetween 2013 and 2018, 353 patients with BM had undergone BM resection at the authors’ institution. Secondary ICU admission was defined as any unplanned admission to the ICU during the initial hospital stay. A multivariable logistic regression analysis was performed to identify preoperatively identifiable risk factors for unplanned ICU readmission.ResultsA total of 19 patients (5%) were readmitted to the ICU. Median overall survival (mOS) of patients with unplanned ICU readmission was 2 months (mo) compared to 13 mo for patients without secondary ICU admission (p<0.0001). Multivariable analysis identified “multiple BM” (p=0.02) and “preoperative CRP levels > 10 mg/dl” (p=0.01) as significant and independent predictors of secondary ICU admission.ConclusionsUnplanned ICU readmission following surgical therapy for BM is significantly related to poor OS. Furthermore, the present study identifies routinely collectable risk factors indicating patients that are at a high risk for unplanned ICU readmission after BM surgery.

Delivery accuracy of VMAT on two beam-matched linacs provided by accelerated go live service.

Dosimetric accuracy is critical when a patient treated with volumetric modulated arc therapy (VMAT) is transferred to another beam-matched linac. To evaluate the performance of Accelerated Go Live (AGL) service, the measured beam characteristics and patient specific quality assurance (QA) results between two AGL-matched linacs were compared. Two VersaHD linacs were installed using the AGL service. After the installation, the beam data such as percentage depth dose (PDD), lateral profiles and output factors for all photon beams were measured. Relative doses were also measured as a function of the multi-leaf collimator (MLC) leaf gap width. Subsequently, VMAT plans were created for prostate, pelvis, head and neck, liver, lung cancers and multiple brain metastases. Dose distributions and point doses were measured by multi-dimensional detectors and ionization chambers for patient specific quality assurance, and comparisons were made between the two linacs. Dose differences in PDDs were all within±1% except the entrance region, and the averaged gamma indices of the lateral profiles were within 0.3. The differences in doses as a function of the MLC leaf gap width between the two linacs were within ±0.5%. For all the plans, gamma passing rates were all higher than 95% with criteria of 2%/2mm. The average and the SD of dose differences on the multi-dimensional detector between both measurements was 0.06±2.12%, and the average of point dose differences was -0.03±0.33%. We have evaluated the AGL performance in the context of beam characteristics and patient specific QA. It was demonstrated that the AGL service provides an accurate VMAT treatment reproducibility for many tumor sites with gamma pass rates greater than 95% under criteria of 2%/2mm.

Spatiotemporal fractionation schemes for stereotactic radiosurgery of multiple brain metastases.

Stereotactic radiosurgery (SRS) is an established treatment for patients with brain metastases (BMs). However, damage to the healthy brain may limit the tumor dose for patients with multiple lesions. In this study, we investigate the potential of spatiotemporal fractionation schemes to reduce the biological dose received by the healthy brain in SRS of multiple BMs, and also demonstrate a novel concept of spatiotemporal fractionation for polymetastatic cancer patients that faces less hurdles for clinical implementation. Spatiotemporal fractionation (STF) schemes aim at partial hypofractionation in the metastases along with more uniform fractionation in the healthy brain. This is achieved by delivering distinct dose distributions in different fractions, which are designed based on their cumulative biologically effective dose ( ) such that each fraction contributes with high doses to complementary parts of the target volume, while similar dose baths are delivered to the normal tissue. For patients with multiple brain metastases, a novel constrained approach to spatiotemporal fractionation (cSTF) is proposed, which is more robust against setup and biological uncertainties. The approach aims at irradiating entire metastases with possibly different doses, but spatially similar dose distributions in every fraction, where the optimal dose contribution of every fraction to each metastasis is determined using a new planning objective to be added to the BED-based treatment plan optimization problem. The benefits of spatiotemporal fractionation schemes are evaluated for three patients, each with >25 BMs. For the same tumor BED10 and the same brain volume exposed to high doses in all plans, the mean brain BED2 can be reduced compared to uniformly fractionated plans by 9%-12% with the cSTF plans and by 13%-19% with the STF plans. In contrast to the STF plans, the cSTF plans avoid partial irradiation of the individual metastases and are less sensitive to misalignments of the fractional dose distributions when setup errors occur. Spatiotemporal fractionation schemes represent an approach to lower the biological dose to the healthy brain in SRS-based treatments of multiple BMs. Although cSTF cannot achieve the full BED reduction of STF, it improves on uniform fractionation and is more robust against both setup errors and biological uncertainties related to partial tumor irradiation.

Rates of hematologic toxicity in WBRT vs SRS.

e14014 Background: Whole brain radiotherapy (WBRT) has historically been a standard of care in patients with multiple brain metastases. Studies show WBRT may be associated with a transient detriment in hematological parameters because of exposure to a larger proportion of circulating lymphocytes, platelets and hematopoietic cells within the bone marrow of the cranium. We tested the hypothesis that stereotactic radiotherapy (SRS) has reduced hematologic toxicity in patients compared to WBRT. Methods: We retrospectively identified 100 patients treated for brain metastasis, with either SRS or WBRT from 2016 to 2019, and queried their pre- and post-treatment hematological parameters including hemoglobin, total white blood cell (WBC), absolute neutrophil count (ANC), absolute lymphocyte count, and platelet count. CTCAE v5.0 was used for grading hematologic toxicities. Serial values were compared by treatment type and controlled for age, gender, &amp; systemic therapy. Student t-test was used for intergroup comparison and p-value &lt;0.05 was considered significant. Results: Of 100 patients, median brain metastases was 3 (range 1-22), 51 received SRS and 49 received WBRT. We observed that patients treated with WBRT had a significantly higher post-treatment reduction in platelet count (-51.2 vs 9.8; p=0.001) and higher incidence of any grade thrombocytopenia (31.2% vs 10%; p=0.019) compared to patients treated with SRS. We also noted that compared with SRS, WBRT was associated with a higher post-treatment reduction in circulating lymphocytes (-0.80 vs 0.14; p = 0.071) and higher incidence of G3+ lymphopenia (43.2% vs 22.2%; p=0.07). Numerical incidence of any G3+ hematological toxicity was also higher in the WBRT group but the difference was not statistically significant (40% vs 28%, p=0.162). Hemoglobin count, WBC, and ANC were not meaningfully different pre- and post-treatment for either group. Conclusions: WBRT results in an increased amount and duration of radiation exposure to circulating intracranial blood volume. In our study, patients treated with WBRT experienced higher rates of clinically significant lymphopenia &amp; thrombocytopenia compared to patients treated with SRS. In addition to the cognitive benefits of SRS compared to WBRT, there may be significant hematologic benefits as well. Further studies are warranted to clarify and validate these findings. [Table: see text]

Retrospective non-inferiority study of stereotactic radiosurgery for more than ten brain metastases.

This study aimed to investigate the clinical benefits of stereotactic radiosurgery (SRS) in patients with > 10 brain metastases (BM) compared to patients with 2-10 BM. The study included multiple BM patients who underwent SRS between 2014 and 2022, excluding patients who underwent whole brain radiotherapy, had a Karnofsky Performance Status score < 60, suspected leptomeningeal disease, or a single BM lesion. Patients were divided into two groups (2-10 and > 10 BM groups) and matched 2:1 based on propensity scores. The primary endpoint was overall survival (OS) in the matched dataset, with intracranial progression-free survival (PFS) as the secondary endpoint. Non-inferiority was established if the upper limit of the 95% confidence interval (CI) of the adjusted hazard ratio was below 1.3. Of the 1042 patients identified, 434 met eligibility criteria. After propensity score matching, 240 patients were analyzed (160 in the BM 2-10 group and 80 in the > 10 BM group). The median OS was 18.2months in the 2-10 BM group and 19.4months in the > 10 BM group (P = 0.60). The adjusted hazard ratio was 0.86 (95% CI: 0.59-1.24), indicating non-inferiority. PFS was not significantly different between the groups (4.8months vs. 4.8months, P = 0.94). The number of BM did not significantly impact OS or PFS. SRS for selected patients with > 10 BM was non-inferior in terms of OS compared to those with 2-10 BM in a propensity score-matched dataset.

Outcome of Brain Metastases Treated with Gamma Knife Stereotactic Radiosurgery: A Retrospective Cohort Study of 205 Cases

Brain metastases (BMs) are the most common expansive intracranial lesions in adults. Approximately 50% of patients diagnosed with new BMs will have >1 BM at the diagnosis. We report our experience with BMs treated with Leksell Gamma Knife stereotactic radiosurgery (GKSR) and evaluate the outcomes. Patients treated by GKSR in our institution between 2008 and 2021 for BMs were evaluated retrospectively. A total of 205 patients (56.6% women) were included, with a median age of 59 years (range, 25-83 years). The breast (n= 85; 42.5%) and lung (n= 76; 38%) were the most common original locations for the primary tumors. Of the 205 patients, 103 (50.3%) had a single BM and 102 (49.7%) had ≥2 BMs. The median number of multiple BMs treated was 4 (range, 2-43). The mean overall survival (OS) time was 6.00 months (95% confidence interval [CI], 5.07-6.93 months) for all BMs. The median rate of tumor control after radiosurgery was 65% (range, 20%-99%) during a median follow-up of 6.00 months (95% CI, 3-84 months). In the overall population, the 1-, 2-, and 5-year OS rate was 37.55%, 25.12%, and 18.51%, respectively. The mean OS time was longer for those with multiple BMs than for those with a single BM (mean, 10 months [95% CI, 6.67-13.33 months] vs. mean, 5 months [95% CI, 4.21-5.70 months]; P= 0.03). Retreatment, tumor stability (control), and progression influenced the OS of patients with BMs, whether single or multiple (P < 0.001). GKSR provides good results in terms of OS and better quality of life for patients with BMs, whether single or multiple. Tumor stability and retreatment influenced the OS of patients with BMs.

Quality assurance and safety of hippocampal avoidance prophylactic cranial irradiation in the multicenter randomized phase III trial (NCT01780675)

ObjectiveNCT01780675, a multicenter randomized phase III trial of prophylactic cranial irradiation (PCI) versus PCI with hippocampal sparing in small cell lung cancer (SCLC) investigated neurocognitive decline and safety. As part of quality assurance, we evaluated if hippocampal avoidance (HA)-PCI was performed according to the NCT01780675 trial protocol instructions, and performed a safety analysis to study the incidence and location of brain metastases for patients treated with HA-PCI. MethodsThis retrospective analysis evaluated the quality of the irradiation given in the randomized controlled trial (RCT) comparing SCLC patients receiving PCI with or without hippocampal avoidance, using intensity modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT). The dose distribution for each patient receiving HA-PCI was retrieved and analyzed to evaluate if the treatment dose constraints were met. A questionnaire was sent out to all participating sites, and data on radiotherapy technique, pre-treatment dummy runs, phantom measurements and treatment electronic portal imaging device (EPID) dosimetry were collected and analyzed. As part of the safety analysis, the follow-up magnetic resonance imaging (MRI) or computerized tomography (CT) scans on which cranial disease progression was first diagnosed were collected and matched to the radiotherapy planning dose distribution. The matched scans were reviewed to analyze the location of the brain metastases in relation to the prescribed dose. ResultsA total of 168 patients were randomized in the NCT01780675 trial in 10 centers in the Netherlands and Belgium from April 2013 until March 2018. Eighty two patients receiving HA-PCI without evidence of brain metastases were analyzed. All patients were treated with 25 Gy in 10 fractions. Dummy runs and phantom measurements were performed in all institutions prior to enrolling patients into the study. The radiotherapy (RT) plans showed a median mean bilateral hippocampal dose of 8.0 Gy, range 5.4–11.4 (constraint ≤ 8.5 Gy). In six patients (7.3%) there was a protocol violation of the mean dose in one or both hippocampi. In four of these six patients (4.9%) the mean dose to both hippocampi exceeded the constraint, in 1 patient (1.2%) only the left and in 1 patient (1.2%) only the right hippocampal mean dose was violated (average median dose left and right 8.9 Gy). All patients met the trial dose constraint of V115%PTV ≤ 1%; however the DmaxPTV constraint of ≤ 28.75 Gy was violated in 22.0% of the patients. The safety analysis showed that 14 patients (17.1%) developed cranial progression. No solitary brain metastases in the underdosed region were found. Two out of 11 patients with multiple brain metastasis developed metastasis in the underdosed region(s). ConclusionsThe radiotherapy quality within the HA-PCI trial is performed according to the protocol guidelines. The dose constraints to the hippocampi are met in the vast majority of cases. In all patients, the volume of the brain for which a higher dose was accepted, is according to the trial. However, within this volume there are small areas with higher doses than advised.

PO-2010 Comparison of Varian Halcyon and Elekta Synergy for HA-WBRT+SIB in multiple brain metastases

PO-2010 Comparison of Varian Halcyon and Elekta Synergy for HA-WBRT+SIB in multiple brain metastases

A study of the prognosis of patients with limited-stage small cell lung cancer who did or did not receive prophylactic cranial irradiation after effective chemoradiotherapy.

To investigate the prognosis of patients with LS-SCLC who responded to chest chemoradiotherapy but did not receive PCI. A retrospective analysis was conducted on LS-SCLC patients who had achieved complete remission (CR) or partial remission (PR) after definitive chemoradiotherapy but did not receive PCI. The survival rates were calculated using Kaplan-Meier method. The prognosis was analyzed using Cox proportional hazard regression model. The main endpoint was OS. Of the 500 patients with LS-SCLC admitted between June 2002 and January 2018, 327 achieved CR or PR after definitive chest chemoradiotherapy, 103 did not receive PCI, and 63 of them developed brain metastases (BM). The 1-year and 3-year OS rates in PCI group were 87.5% and 42.3% respectively, versus 70.4% and 20.9% for non-PCI group(P=0.002). The median survival time after BM was 8.7 months (range: 0.3-48.7), and 3-year OS rate was 15.0%, the median survival time of patients without BM was 20.1 months (range: 2.9-79.4), and 3-year OS was 33.4% (P=0.014). Patients with BM were subsequently treated with palliative therapy. Multivariate analysis showed that compared with no treatment, brain radiotherapy alone (HR: 0.131, 95%CI: 0.035-0.491, P=0.003) and radiotherapy combined with chemotherapy (HR: 0.039, 95%CI: 0.008-0.194, P<0.001) significantly reduced the risk of death. Multiple BM (HR: 2.391, 95%CI: 1.082-5.285, P=0.031) was an independent adverse prognostic factor for OS. LS-SCLC patients who achieved good response after chest chemoradiotherapy without receiving PCI were prone to develop BM and have a poor prognosis. Multiple BM was an independent adverse prognostic factor. PCI remains the standard of care for LS-SCLC patients.

Multiple craniotomies in a single surgery — the resection of scattered brain metastases

Patients with brain metastases (BM), who can benefit from resection of multiple scattered lesions, often will not be offered a procedure involving multiple craniotomies in one session due to the overall poor prognosis. However, carefully selected candidates may well benefit from the resection of multiple lesions using multiple craniotomies through a significantly shortened hospital stay, aggressive decompression, and rapid eligibility for adjuvant therapies. In this retrospective analysis, the records of patients, who were treated for multiple BM using one surgical session involving multiple craniotomies, were reviewed. A group of patients with multiple BM, whose surgery only involved one craniotomy, were assigned to a control group. Clinical and surgical characteristics, preoperative and postoperative Karnofsky Performance Scale (KPS), complication rate, preoperative tumor size, number of lesions, number of craniotomies, skin incisions, and intraoperative repositioning of patients were recorded. Thirty-three patients were included in the multiple-craniotomy group. Thirty patients underwent two craniotomies, while three cases involved three craniotomies. Seven patients (21%) were intraoperatively repositioned from a prone to a supine position, which required an average of 23.3 ± 9.3 min from wound closure to the following skin incision. Thirty-six patients with multiple BM and matching characteristics, who received only one craniotomy for the dominant lesion, served as the control group. No difference was detected in postoperative KPS (p = 0.269), complication rate (p = 0.612), rate of new postoperative neurological deficits (p = 0.278), length of intensive care unit (ICU) (p = 0.991), and hospital stay (p = 0.913). There was a significant difference in average preoperative tumor size (p = 0.002), duration of surgery (p < 0.001), and extent of resection (p = 0.002). In the age of personalized medicine, selected patient may benefit from a single surgery for BM using multiple craniotomies. This study shows no significant increase of the perioperative complication rate for surgeries with multiple craniotomies.

Mapping distribution of brain metastases in renal cell carcinoma (RCC) and association with clinical features.

727 Background: Brain metastases (BM) are frequently observed in metastatic RCC (mRCC) with a tendency to present with hemorrhagic BM. Distribution patterns of BM in RCC and associations with clinical outcomes are not well understood. Here we present a detailed distribution analysis in a surgically resected BM RCC cohort with a focus on clinically relevant associations. Methods: A retrospective analysis was performed on patients (pts) with mRCC who underwent craniotomy for BM at our institution. We reviewed gadolinium-enhanced MRI brain and CT head (if available) at the time of BM diagnosis. We assessed the presence of hemosiderin on MRI or hemorrhage on CT in the BM lesion and marked each at their corresponding anatomic location. Public brain atlases were used for distribution analysis. Overall survival (OS) from the date of BM diagnosis and CNS progression free survival (CNS-PFS) from the date of craniotomy were calculated. Results: A total of 67 BM were analyzed from 46 pts. 23 with synchronous BM, 9 with two and 6 with 3 concurrent BM. Most patients were male (n=35, 76%) with a median age at diagnosis of 63 years. Primary histology was clear cell in 42 pts (91%) and 10 pts (22%) had renal vein thrombosis (RVT) at primary diagnosis. IMDC scores at time of BM diagnosis were favorable in 20%, intermediate in 60% and poor in 20%. Hemosiderin (MRI) or hemorrhage (CT) was seen in 82% and 80% of BM, respectively. 55% of lesions were left sided, 45% frontal, 21% parietal, 18% occipital, 7% temporal and 6% cerebellar. Posterior circulation and posterior cerebral artery territories contained 42% and 34% of BM despite supplying only 30% and 16% of the brain volume, respectively. Patients with solitary BM had higher Karnofsky performance status (p=0.006) and lower disease burden (p=0.004) than those with multiple BM. Shorter CNS-PFS was seen in association with hemosiderin on MRI (log-rank p=0.04) and RVT in primary specimen (log-rank p=0.002). IMDC risk scores (log-rank p&lt;0.001) predicted OS. On multivariable OS analysis, BM lateralized to the right (HR 2.6, p=0.06), hemosiderin in BM (HR 6.5, p=0.02) and IMDC risk groups (intermediate HR 2.9, poor risk HR 25.6, p&lt;0.04) were independent prognostic factors for shorter OS. Conclusions: The above-presented lesion mapping method shows clinically relevant findings in RCC BM. Tumoral hemosiderin deposits appear a potential parameter to predict outcomes in RCC BM which deserve further study and validation.

Initial Treatment of Aumolertinib in Combination with Bevacizumab for Advanced NSCLC with Primary EGFR T790M Mutation: A Report of Three Cases and Literature Review

With the development of sequencing technology, the detection rate of non-small cell lung cancer (NSCLC) with primary epidermal growth factor receptor (EGFR) T790M mutation is increasing. However, the first-line treatment for primary EGFR T790M-mutated NSCLC still lacks standard recommendations. Here, we reported three advanced NSCLC cases with EGFR-activating mutation and primary T790M mutation. The patients were initially treated with Aumolertinib combination with Bevacizumab; among which, one case was discontinued Bevacizumab due to bleeding risk after treatment for three months. Treatment was switched to Osimertinib after ten months of treatment. Another case switched to Osimertinib and discontinued Bevacizumab after thirteen months of treatment. The best effect response in all three cases was partial response (PR) after initial treatment. Two cases progressed after first-line treatment and progression-free survival (PFS) was eleven months and seven months respectively. The other one patient had persistent response after treatment, and the treatment duration has reached nineteen months. Two cases had multiple brain metastases before administration and the best response to intracranial lesions was PR. The intracranial PFS was fourteen months and not reached (16+ months), respectively. There were no new adverse events (AEs), and no AEs of grade three or above were reported. In addition, we summarized the research progress of Osimertinib in the treatment of NSCLC with primary EGFR T790M mutation. In conclusion, Aumolertinib combined with Bevacizumab in the treatment of advanced NSCLC with primary EGFR T790M mutation has a high objective response rate (ORR) and control ability of intracranial lesions, which can be used as one of the initial options for first-line advanced NSCLC with primary EGFR T790M mutation. .