Parenchymal Metastases Research Articles

Clinical significance of intensity-modulated radiotherapy (IMRT) to the distant metastatic lymph nodes for metastatic cervical cancer

ObjectiveTo retrospectively explore the clinical significance of radiotherapy to the distant metastatic lymph nodes (cervical/ clavicular/ mediastinal et al.) in metastatic cervical cancer. Hereinto, these cervicothoracic lymph nodes were metastasized from IB1-IVA (initial stage at first treatment), and IVB initially had metastatic disease in these areas at diagnosis.MethodsMetastatic cervical cancer only with the distant cervicothoracic metastatic lymph nodes (cervical/ clavicular/ mediastinal et al.), without distant parenchymal organs metastasis such as lung, liver, bone, and peritoneum, were enrolled in the analysis. These patients were classified into IB1-IVA and IVB based on their initial stage of first treatment. All patients received IMRT for the distant metastatic lymph nodes. The progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan–Meier method.ResultsOverall, the median PFS was 9 months, and the median OS was 27 months. The subgroup analysis showed that for IB1-IVA, the median PFS was 11 months, and the median OS was 30.5 months. For IVB, the median PFS was 8 months, and the median OS was 16 months.ConclusionRadiotherapy is beneficial to the distant metastatic lymph nodes (cervical/ clavicular/ mediastinal et al.), and could effectively bring the longer PFS and OS for metastatic cervical cancer.

1377P Association of anatomic proximity of brain parenchymal metastasis to the CSF space and upfront stereotactic radiosurgery to subsequent leptomeningeal metastasis development in brain metastatic NSCLC

1377P Association of anatomic proximity of brain parenchymal metastasis to the CSF space and upfront stereotactic radiosurgery to subsequent leptomeningeal metastasis development in brain metastatic NSCLC

Genetic characteristics of cerebrospinal fluid-derived circulating tumor DNA in brain metastases of lung adenocarcinoma.

e20503 Background: Brain metastases (BM), encompassing parenchymal metastases (PM) and leptomeningeal metastases (LM), are a common and fatal complication of advanced lung adenocarcinoma (LUAD). However, the genomic disparities between PM and LM, as determined by cerebrospinal fluid (CSF)-derived circulating tumor DNA (ctDNA), and its clinical utility as a liquid biopsy medium remain unclear. Methods: We conducted a retrospective study involving 33 patients diagnosed with BM from LUAD, comprising 16 cases with PM and 17 cases with LM, at Shandong Cancer Hospital between March 2018 and June 2021. CSF and matched peripheral blood lymphocyte samples were collected from all patients, and plasma samples were collected from 25 of them. Genomic profiles of CSF and plasma in patients with PM and LM were compared. CSF-ctDNA, plasma-ctDNA, and DNA from matched peripheral blood lymphocytes underwent next-generation sequencing (NGS) based on a 769 cancer-related gene panel. Results: A total of 363 mutations were detected in CSF-ctDNA, with 90.9% (30/33) of all LUAD patients with PM or LM showing mutations. EGFR mutations were the most common, occurring in PM samples from 56.3% (9/16) of patients and in LM samples from 76.5% (13/17) of patients, followed by other frequently mutated driver genes, including TP53 in 19 (57.6%) patients, MLH1 in 9 (27.3%) patients, and KMT2C in 8 (24.2%). Notably, EGFR 19del was more prevalent as a driver mutation in patients with LM compared to those with PM in our study, particularly the p.E746_A750del mutated subtype. Furthermore, the frequency of mutations in the mismatch repair (MMR) pathway was significantly higher in patients with LM than in those with PM. Additionally, CSF exhibited a more comprehensive profile of driver genomic mutations than matched plasma in patients with any form of BM, accompanied by a higher variation burden and detection of druggable mutations. Conclusions: CSF-ctDNA sequencing revealed distinct genomic patterns in patients with BM, particularly in LM, and could potentially enhance the management of BM patients compared to plasma.

Clinical features and outcomes of patients with breast cancer with leptomeningeal carcinomatosis.

e13162 Background: Leptomeningeal carcinomatosis (LMC) is a rare, but deadly complication in breast cancer, with prior studies showing median overall survival (OS) of 15 weeks. There is a paucity of data on histologic and receptor subtype-specific survival, and there is no standard of care currently for treatment of LMC in breast cancer. We reviewed the outcomes of a contemporary cohort of breast cancer patients (pts) with LMC. Methods: This is a single-institution retrospective analysis of 38 female breast cancer pts diagnosed with LMC between 2016-2023, based on radiographic features and/or positive cerebrospinal fluid (CSF) cytology or CSF circulating tumor cells (CTCs). Patients consented to share information with a research biorepository, and we conducted a chart review of their clinical features and OS with LMC. Results: 25 pts (65.8%) had invasive ductal carcinoma (IDC), 7 pts (18.4%) had invasive lobular carcinoma (ILC), 4 (10.5%) had metaplastic carcinoma, and 2 (5.3%) had mixed IDC/ILC. 22 pts (57.9%) had triple-negative breast cancer (TNBC), 12 (31.6%) had estrogen receptor positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-), and 4 (10.5%) had HER2+ disease. Median age at LMC diagnosis was 50 years. Median time between Stage IV and LMC diagnosis was 11 months. Pts received a median of 2 lines of systemic therapy for metastatic disease prior to LMC diagnosis. 11 pts (28.9%) had parenchymal brain metastasis prior to LMC diagnosis. 32 pts (84.2%) had signs of LMC on Magnetic Resonance Imaging of the brain and/or spine at diagnosis. 25 pts underwent CSF cytology and 13 pts underwent CSF CTC evaluation at LMC diagnosis; 14/25 pts (56%) had positive CSF cytology and 10/13 pts (76.9%) had detectable CSF CTCs. 21 pts (55.3%) underwent whole-brain radiotherapy, and 2 pts (5.3%) received proton craniospinal irradiation. 21 pts (55.3%) received IT therapy. 27 pts (71.1%) received at least 1 line of systemic therapy post-LMC diagnosis. Median OS between LMC diagnosis and death or last oncology follow up for the entire cohort was 5 months (range 0-57 months, 95% CI 3.0-8.0). There was a significant difference in median OS with LMC by receptor subtype: TNBC 3.5 months, ER+/HER2- 8 months, and HER2+ 23 months (p=0.0047). Two HER2+ pts survived ≥ 3 years post-LMC diagnosis with anti-HER2 antibody-drug conjugates and tyrosine kinase inhibitors +/- stereotactic radiosurgery (SRS) to parenchymal brain metastases. Amongst 9 pts with ER+/HER2-low disease, longer survival with LMC (≥ 16 months) was observed with trastuzumab deruxtecan, IT topotecan +/- IT trastuzumab, and SRS to parenchymal brain metastases. Conclusions: This study highlights heterogeneity in outcomes amongst breast cancer pts with LMC by receptor subtype, as well as improvement in outcomes for selected pts treated with novel therapeutics and a multidisciplinary approach. Larger prospective studies are needed to inform treatment paradigms for LMC.

PROTAC EZH2 degrader-1 overcomes the resistance of podophyllotoxin derivatives in refractory small cell lung cancer with leptomeningeal metastasis

BackgroundLeptomeningeal metastasis (LM) of small cell lung cancer (SCLC) is a highly detrimental occurrence associated with severe neurological disorders, lacking effective treatment currently. Proteolysis-targeting chimeric molecules (PROTACs) may provide new therapeutic avenues for treatment of podophyllotoxin derivatives-resistant SCLC with LM, warranting further exploration.MethodsThe SCLC cell line H128 expressing luciferase were mutated by MNNG to generate H128-Mut cell line. After subcutaneous inoculation of H128-Mut into nude mice, H128-LM and H128-BPM (brain parenchymal metastasis) cell lines were primarily cultured from LM and BPM tissues individually, and employed to in vitro drug testing. The SCLC-LM mouse model was established by inoculating H128-LM into nude mice via carotid artery and subjected to in vivo drug testing. RNA-seq and immunoblotting were conducted to uncover the molecular targets for LM.ResultsThe SCLC-LM mouse model was successfully established, confirmed by in vivo live imaging and histological examination. The upregulated genes included EZH2, SLC44A4, VEGFA, etc. in both BPM and LM cells, while SLC44A4 was particularly upregulated in LM cells. When combined with PROTAC EZH2 degrader-1, the drug sensitivity of cisplatin, etoposide (VP16), and teniposide (VM26) for H128-LM was significantly increased in vitro. The in vivo drug trials with SCLC-LM mouse model demonstrated that PROTAC EZH2 degrader-1 plus VM26 or cisplatin/ VP16 inhibited H128-LM tumour significantly compared to VM26 or cisplatin/ VP16 alone (P < 0.01).ConclusionThe SCLC-LM model effectively simulates the pathophysiological process of SCLC metastasis to the leptomeninges. PROTAC EZH2 degrader-1 overcomes chemoresistance in SCLC, suggesting its potential therapeutic value for SCLC LM.

Abstract 6472: Response to PARP inhibitors in patients with breast cancer metastatic to the central nervous system

Abstract Background: Central nervous system (CNS) metastasis from breast cancer can be challenging to treat due to the limited blood brain barrier penetration of many systemic therapies. PARP inhibitors (PARPi) block single-strand DNA break repairs and have activity in cancers with homologous recombination repair deficiency; they are FDA approved for patients with metastatic HER2 negative breast cancer with germline BRCA1/2 mutations. While preclinical studies suggest that PARPi have CNS penetration, clinical data is limited. The goal of our study is to describe the clinical benefit of PARPi in patients with breast cancer CNS metastasis. Methods: This retrospective case series was conducted at three academic cancer centers (Johns Hopkins, Dana-Farber, and Duke) and included patients with the following criteria: (1) age≥18 years with a breast cancer diagnosis (any subtype); (2) diagnosis of parenchymal brain metastasis or leptomeningeal disease (LMD); and (3) received PARPi (olaparib, talazoparib) for CNS metastasis. Clinical and pathologic information were analyzed with descriptive statistics (median, range) and Kruskal-Wallis rank sum tests. Survival analysis was performed using Kaplan-Meier curves with log-rank p-values. Results: Although this analysis includes one center’s experience, we will present a combined dataset (N = 45) at the main conference. 11 patients were identified at Johns Hopkins. 4 (36.4%) were Black and 6 (54.5%) were White; 6 (54.5%) had ER+HER2- disease and 5 (45.5%) had TNBC at time of brain metastasis; 5 (45.5%) had BRCA1 mutations, 5 (45.5%) had a BRCA2 mutations, and 1 patient (9%) had a BARD1 mutation; 7 (63.6%) had brain metastasis and 4 (36.4%) had LMD. Median lines of therapy prior to PARPi was 6 [1 - 11]; 8 patients (72.7%) had previous CNS radiation (5 SRS and 3 WBRT) and 3 (27.3%) had previous CNS surgery. On average, patients remained on PARPi for 5 months [0.5 - 66], and overall survival (OS) time from PARPi to death was 16 months [2 - 66]. Time on PARPi was 5 months [2 - 66] for patients with brain metastasis and 3 months [0.5 - 10] for those with LMD (p=0.22). Duration of PARPi and OS did not differ significantly between ER+HER2- and TNBC (p=0.74 and 0.69, respectively), BRCA 1 and 2 (p=0.78 and 0.72, respectively), or brain and LMD metastasis (p=0.22 and 0.91, respectively). Black patients had significantly shorter PARPi duration and survival than White patients (PARPi 2 vs. 8 months, p=0.028 and OS 4 vs 18 months, p=0.028). Prior CNS radiation was significantly associated with longer PARPi duration and survival (PARPi 5 vs 1 month, p=0.02 and OS 17 vs. 3 months, p=0.032). Prior CNS surgery was significantly associated with longer PARPi duration, but not overall survival (PARPi 18 vs 3 months, p=0.05 and OS 28 vs. 7 months, p=0.14). Conclusions: PARPi are associated with significant clinical benefit in patients with breast cancer CNS metastasis. Larger data series will help confirm these observations. Citation Format: Seoho Lee, Rani Bansal, Melissa E. Hughes, Amanda E. Van Swearingen, Heather N. Moore, David O. Kamson, Solmaz Sahebjam, Greg Kirkner, Anna Gorfinkel, Sarah Sammons, Nancy U. Lin, Carey Anders, Cesar A. Santa-Maria. Response to PARP inhibitors in patients with breast cancer metastatic to the central nervous system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6472.

Treatment modalities and survival outcomes in prostate cancer parenchymal brain metastasis.

Prostate cancer (PCa) parenchymal brain metastases are uncommon and troubling observations in the course of the disease. Our study aims to evaluate the prevalence of brain metastases among PCa patients while reporting various therapeutic modalities, clinical features, and oncological outcomes. We retrospectively identified 34 patients with parenchymal brain metastasis out of 4575 patients using a prospectively maintained database that contains clinicopathologic characteristics of PCa patients between January 2012 and December 2021. Based on the three treatment modalities used, the patients were divided into three groups: stereotactic radiosurgery (SRS), whole brain radiotherapy (WBRT), and systemic therapy alone. The Kaplan-Meier curve was used to calculate overall survival [OS] probability and the Cox proportional hazards regression model was used to compare between groups. At the time of brain metastasis diagnosis, the median age was 66 years, the median (interquartile range [IQR]) prostate-specific antigen (PSA) was 2.2 (0.1-26.6) ng/ml and the median (IQR) months from initial PCa diagnosis to brain metastasis development was 70.8 (27.6-100.9). The median (IQR) primary Gleason score was 8 (7-9) and over a median (IQR) follow-up time of 2.2 (1.2-16.5) months, 76.5% (n = 26) of the patients died. Thirteen (38.2%) patients had solitary lesion, whereas 21 (61.8%) had ≥2 lesions. The lesions were supratentorial in 19 (55.9%) patients, infratentorial in six (17.6%), and both sides in nine (26.5%). Among all 34 patients, 10 (29.4%) were treated with SRS, seven (20.6%) with WBRT, and 17 (50%) with systemic therapy alone. OS varied greatly between the three treatment modalities (log-rank test, p = 0.049). Those who were treated with SRS and WBRT had better OS compared with patients who were treated with systemic therapy alone (hazard ratio: 0.37, 95% confidence interval: 0.16-0.86, p = 0.022). In our single-institutional study, we confirmed that PCa brain metastasis is associated with poor survival outcomes and more advanced metastatic disease. Furthermore, we found that SRS and WBRT for brain metastasis in patients with recurrent PCa appear to be associated with improved OS as compared with systemic therapy alone and are likely secondary to selection bias.

Clinical characteristics and their influences on the survival of leptomeningeal metastasis derived from lung adenocarcinoma harboring epithelial growth factor receptor mutation

Objective: To analyze the clinical characteristics of leptomeningeal metastasis (LM) patients from epithelial growth factor receptor (EGFR)-mutated lung adenocarcinoma, and their impacts on the survival of the patients. Methods: From July 2018 to July 2022, the clinicopathological data of 81 patients diagnosed as EGFR-mutated lung adenocarcinoma LM by cytopathology who admitted to the Department of Oncology of Xiangya Hospital of Central South University were retrospectively analyzed, including 33 males and 48 females. The age ranged from 31 to 76 years, with a median age of 54 years. All the 81 patients were followed up, with a median follow-up of 21.0 months (95%CI: 12.5 to 29.5 months). The Kaplan Meier method was used to draw survival curve. Cox proportional hazards regression model was used to analyze the impact of the factors on the survival of patients. Results: Among the 81 patients, the interval between the initial diagnosis of lung cancer and the pathological diagnosis of LM in cerebrospinal fluid (CSF) was 0-108 months, with a median interval of 14 months. Fifty-two patients (64.2%) used the third-generation epithelial growth factor receptor tyrosine kinase inhibitor (EGFR-TKIs), while 17 patients (21.0%) used EGFR-TKIs in combination with other drugs, and 12 patients (14.8%) were treated with best supportive care (BSC). Sixty patients (74.1%) had a Kanofsky performance status (KPS) score of less than 60 points, and 71 patients (87.7%) had brain parenchymal metastasis and/or spinal metastasis. Twenty-two patients (27.2%) used pemetrexed through intrathecal CSF, and 17 patients (21.0%) used pemetrexed through the Ommaya sac to the CSF of the ventricle. The incidence of adverse event related to the administration of pemetrexed through CSF was 64.1% (25/39), mainly manifested as myelosuppression, including 22 patients of leukocyte reduction, 25 patients of hemoglobin reduction, and 14 patients of platelet reduction. The median post-leptomeningeal metastasis overall survival (pLM-OS) in 81 patients was 11.0 (95%CI: 7.7-14.3) months. KPS score≥60 points (HR=0.407, 95%CI: 0.170-0.973, P=0.043), CSF cytology negative after treatment (vs persistent positive, HR=0.351, 95%CI: 0.155-0.792, P=0.012), intraventricular administration of pemetrexed (vs non intraventricular administration of pemetrexed, HR=0.319, 95%CI: 0.137-0.745, P=0.008) and the treatment with third-generation EGFR-TKIs after LM (vs EGFR-TKIs in combination with other drugs, HR=0.486, 95%CI: 0.237-0.998, P=0.049) were a factor affecting pLM-OS of patients. Conclusions: Brain parenchyma, or/and spine are the most sites where the LM patients concurrently metastasize. KPS score≥60 points and CSF cytology negative after treatment, intraventricular administration of pemetrexed and the treatment with third-generation EGFR-TKIs are indictors affecting pLM-OS of the patients.

A retrospective analysis for investigating the relationship between FIGO stage IVA/IVB and cytoreductive surgery with prognosis in epithelial ovarian cancer.

To investigate the effect of primary debulking surgery (PDS), NACT followed by interval debulking surgery (NACT-IDS), and chemotherapy alone on the prognosis of FIGO stage IV epithelial ovarian cancer (EOC) with different metastatic patterns. We retrospectively analyzed 133 cases of FIGO stage IV EOC with pleural effusion (stage IVA), parenchymal metastases (stage IVB), or extra-abdominal lymph node metastases (stage IVB) at our Hospital between January 2014 and July 2021. Among 133 cases with stage IV disease, 16.5% (n=22) presented with pleural effusion, 46.6% (n=62) with parenchymal metastases, and 36.9% (n=49) with extra-abdominal lymph node metastases. Regardless of the metastatic patterns, the 90.2% (n=120) of cases who underwent PDS/NACT-IDS exhibited a significantly superior overall survival (OS) compared to the 9.8% cases (n=13) who received chemotherapy alone (32 vs 17 months, p=0.000). The cohort was further stratified into 58 cases (48.3%) with R0, 41 cases (34.2%) with R1, and 21 cases (17.5%) with R2. The median OS of cases with R0 was significantly better than that of cases with R1/R2 (74 vs 27 months, p=0.000). There was no significant difference in median OS between PDS and NACT-IDS (43 vs 31 months, p=0.676), as well as between FIGO IVA and IVB (35 vs 31 months, p=0.582). Additionally, the metastatic patterns and the number of neoadjuvant chemotherapy cycles (≤4 or >4) did not demonstrate any prognostic significance for median OS (p=0.820 and 33 vs 26 months, p=0.280, respectively). Regardless of FIGO IVA and IVB stages or metastatic patterns, patients diagnosed with stage IV EOC may benefit from cytoreductive surgery with abdominal R0, compared with chemotherapy alone.

Phase II study of nivolumab (nivo) in combination with relatlimab (rela) in patients (pts) with active melanoma brain metastases (MBM).

TPS9605 Background: More than half of all pts diagnosed with metastatic melanoma (MM) will develop brain metastases. Despite this prevalence, pts with MBM are excluded from the majority of clinical trials, preventing them from potential benefit of novel therapies. Long-term outcomes of the CheckMate 204 study combining ipilimumab (ipi) (3mg/kg) plus nivo (1 mg/kg) for asymptomatic MBM reported an intracranial (IC) response in 54% of pts. The 36-month IC progression-free survival (PFS) was 54% and overall survival (OS) was 72%. Grade 3 or 4 treatment-related adverse events (TRAEs) occurred in 55% of pts. RELATIVITY-047, a global phase II/III randomized study, reported on the fixed-dose combination of nivo (480 mg) and rela (a LAG-3–blocking antibody,160 mg) compared to nivo (480 mg) alone for pts with advanced unresectable and untreated melanoma. The combination demonstrated significantly improved PFS and improved OS and objective response rate (ORR) compared to monotherapy. At 19.3 months of median follow-up, only the PFS benefit was statistically significant with a hazard ratio (HR) of 0.78 (95% CI 0.64-0.94). The OS benefit was not statistically significant (HR 0.8, 95% CI 0.64-1.01), and the descriptive ORR was 43.1% compared to 32.6% for single agent nivo. Grade 3 or 4 TRAEs occurred in 21% of pts in the combination group compared to 11% in the monotherapy group with no new safety signals. The nivo/rela combination has been FDA approved for the treatment of pts with MM but has not been studied in pts with MBM. We hypothesize that nivo/rela will be safe and tolerable for pts with MBM and demonstrate favorable outcomes compared to nivo monotherapy with fewer AEs in contrast to ipi/nivo combination. Methods: This single arm, single center, open-label phase II trial will evaluate the safety and efficacy of nivo/rela in pts with MBM (NCT05704647). 30 MBM pts who are treatment naïve to anti-PD-1 therapy will be enrolled. At least one unirradiated parenchymal brain metastasis at least 5 mm or larger is required for inclusion. Asymptomatic pts not requiring steroids for the management of their neurological symptoms are eligible. Pts requiring urgent local therapy with radiation or surgery are not eligible. Pts will be treated with nivo (480 mg)/rela (160 mg) every 4 weeks for up to 25 cycles, disease progression, or unacceptable toxicity. The primary objective is to evaluate IC ORR (CR + PR) by MRI per modified RECIST 1.1 criteria. Monitoring for futility will be performed using the Bayesian Optimal Phase 2 (BOP2) design. Thirty evaluable patients will provide 82% power to detect a difference between the historical IC ORR of 20% for nivo alone to a targeted ORR of 40% for nivo/rela. Longitudinal research blood, tissue, and microbiome samples will be collected along with neurocognitive assessment and quality of life surveys. Clinical trial information: NCT05704647 .

Safety and survival in adult women with platinum sensitive relapsed BRCA mutant ovarian cancer: A study of patients in Olaparib Turkey Early Access Program—LynTurk study.

e17509 Background: SOLO-2 trial results have proven the efficacy of Olaparib in BRCA-mutant platinum-sensitive relapsed ovarian cancer patients. LynTurk as an open label, multi-center study, designed to show the real world safety and efficacy results of Turkey Olaparib managed access program. Methods: Patients with BRCA mutated relapsed ovarian cancer who are in complete or partial response following platinum based chemotherapy were eligible for Olaparib maintenance in Turkish managed access program. The primary aim was safety. Progression free survival, overall survival were the secondary endpoints. Results: Between December 2014 and March 2021, 48 patients were accepted for program. Due to immaturity of data, in this report, a total of 26 patient results were analyzed. BRCA2 mutation was present in 5 patients, one patient have both BRCA1 and BRCA2 mutations; 20 cases were found to be BRCA1 mutated. The median age of patients was 51 (29-61) years. All patients have high grade serous adenocarcinoma of ovary or primary peritoneal carcinoma. The most common site of involvement are lymph nodes and peritoneal surfaces; in 11% of cases there are liver parenchyma metastasis. All of the patients received at least two lines of platinum-based chemotherapy; median 3 lines (2-4) of treatment were applied before Olaparib maintenance. Previous bevacizumab treatment was allowed in this program, 53.8% of cases were received at least 3 cycles, maintenance bevacizumab was given to 12 patients. Median treatment duration with Olaparib was 26,2 months (3-80m). In 30.7% of cases no adverse events were noted, at least one level dose reduction was needed for 50% of patients due to toxicity. Hematological adverse events were the mostly encountered followed by dyspepsia and fatigue. Anemia was the reason for permanent drug discontinuation in 2 patients (0.7%). No febrile neutropenia was reported. During the follow-up, no secondary malignancy and pneumonitis was noted. Median progression free survival from the end of last chemotherapy was 19.3 months. One-year PFS rate was 88.4% and 2-y PFS rate was 53.8%. One-year OS rate from the end of chemotherapy was 92.3% and 2-year was 61.5%. Conclusions: The real world data from Turkey managed access program has showed that Olaparib has a safety profile in paralel with clinical trials (SOLO). No new safety signals were reported. Although a heterogenous population including heavily pretreated patients, maintenance Olaparib was found effective. This report will be updated as the data of all intent to treat population will gather and will get mature.

Identification of incidental brain tumors in prostate cancer patients via PSMA PET/CT.

Brain metastases are rare in patients with prostate cancer and portend poor outcome. Prostate-specific membrane antigen positron emission tomography (PSMA PET)/CT scans including the brain have identified incidental tumors. We sought to identify the incidental brain tumor detection rate of PSMA PET/CT performed at initial diagnosis or in the setting of biochemical recurrence. An institutional database was queried for patients who underwent 68Ga-PSMA-11 or 18F-DCFPyL (18F-piflufolastat) PET/CT imaging at an NCI-designated Comprehensive Cancer Center from 1/2018 to 12/2022. Imaging reports and clinical courses were reviewed to identify brain lesions and describe clinical and pathologic features. Two-thousand seven hundred and sixty-three patients underwent 3363 PSMA PET/CT scans in the absence of neurologic symptoms. Forty-four brain lesions were identified, including 33 PSMA-avid lesions: 10 intraparenchymal metastases (30%), 4 dural-based metastases (12%), 16 meningiomas (48%), 2 pituitary macroadenomas (6%), and 1 epidermal inclusion cyst (3%) (incidences of 0.36, 0.14, 0.58, 0.07, and 0.04%). The mean parenchymal metastasis diameter and mean SUVmax were 1.99cm (95%CI:1.25-2.73) and 4.49 (95%CI:2.41-6.57), respectively. At the time of parenchymal brain metastasis detection, 57% of patients had no concurrent extracranial disease, 14% had localized prostate disease only, and 29% had extracranial metastases. Seven of 8 patients with parenchymal brain metastases remain alive at a median 8.8 months follow-up. Prostate cancer brain metastases are rare, especially in the absence of widespread metastatic disease. Nevertheless, incidentally detected brain foci of PSMA uptake may represent previously unknown prostate cancer metastases, even in small lesions and in the absence of systemic disease.

Brain parenchymal and leptomeningeal metastasis in non-small cell lung cancer

Patients with advanced non-small cell lung cancer (NSCLC) are prone to brain metastases (BM), which essentially include brain parenchymal metastases (PM) and leptomeningeal metastases (LM). We conducted a retrospective study to comprehensively assess the clinical characteristics and risk factors of patients with advanced NSCLC who develop PM and LM. Patients with advanced NSCLC were enrolled. These patients were then divided into three groups for analysis: patients without BM (No-BM), patients with PM and patients with LM. Data on clinical characteristics of each patient at the time of diagnosis advanced NSCLC were extracted and analyzed. In addition, prediction models were developed and evaluated for PM and LM. A total of 592 patients were enrolled in the study. BM was present in 287 patients (48.5%). Among them, 185 and 102 patients had PM or LM. Patients with LM had a higher proportion of EGFR exon 21point mutations (L858R) compared to patients with No-BM and PM (p < 0.0001). The median time to the onset of PM and LM from the diagnosis of advanced NSCLC was 0 months and 8.3 months, respectively. Patients with LM had a statistically shorter over survival (OS) compared to either No-BM or PM patients (p < 0.0001). Based on independent predictive variables, two nomogram models were constructed to predict the development of PM and LM in advanced NSCLC patients, and the C-indexes were 0.656 and 0.767, respectively. Although both considered as BM, PM and LM had different clinical characteristics. And the nomogram showed good performance in predicting LM development, but not PM.

Molecular characteristics and prognostic factors of leptomeningeal metastasis in non-small cell lung cancer

BackgroundNon-small cell lung cancer with leptomeningeal metastasis (NSCLC-LM) is emerging as a new management challenge for oncologists and is associated with poor prognosis. This study aimed to investigate the molecular characteristics and prognostic factors of NSCLC-LM. MethodsThis retrospective study included 97 patients with NSCLC-LM between January 2015 and October 2021. Progression-free survival (PFS) and overall survival (OS) were evaluated. Gene mutations were detected by next-generation sequencing (NGS). ResultsThe median PFS and OS were 8.4 (95 % confidence interval [CI]: 4.839–11.901) and 14.0 (95 % CI: 9.254–18.746) months, respectively. Sixty-seven patients harboured epidermal growth factor receptor-mutated (EGFRm): L858R (34), 19del (29), T790M (13), and G719C with L861Q (1). Other mutations included ALK (5), ROS1 (3), KRAS (1), TP53 (14), MET amplification (6). The detection rate and types of circulating tumour DNA (ctDNA) in the cerebrospinal fluid (CSF) samples were higher than the paired plasma samples. Patients with EGFR mutations had a longer median OS than those without mutations (19.0 vs. 13.0 months, P = 0.015). Patients with gene mutations had shorter median OS than those without mutations, such as ALK (11.8 vs. 19.9 months, P = 0.014), ROS1 (12.7 vs. 19.8 months, P = 0.014), KRAS (4.0 vs. 19.0 months, P = 0.005), TP53 (15.0 vs. 19.0 months, P = 0.014), and MET amplification (6.0 vs. 19.0 months, P = 0.003). Multivariate analysis indicated that MET amplification was an independent predictor of poor survival. Along with Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥ 3, LM accompanied with brain parenchymal metastasis (BPM), extracranial disease, and seizures were independent predictors of poor survival, whereas intrathecal chemotherapy, and third-generation EGFR-TKIs were independent predictors of favorable survival. ConclusionsCSF ctDNA detected using NGS had a high sensitivity for NSCLC-LM, showing high potential in detecting driver and drug-resistant gene mutations. Genomic profiles, combined with clinically relevant prognostic factors, will guide individualised treatments and improve the outcomes of NSCLC-LM patients.

Parenchymal liver metastasis in advanced ovarian cancer: Can bowel involvement influence the frequency and the related mortality rate?

ObjectiveThis retrospective study estimates the frequency of parenchymal liver metastasis (PLM) and the overall survival (OS) rate of patients with FIGO Stage IIIC-IV Advanced Epithelial Ovarian Cancer (EOC) with bowel involvement. Study designBetween November 2008 and July 2020, all consecutive patients with FIGO Stage IIIC-IV EOC who underwent Visceral Peritoneal Debulking and bowel resection(s) at the Gynaecological Oncology Unit of “Centro di Riferimento Oncologico (CRO)”, Aviano, Italy, without evidence of PLM at pre-operative imaging assessment, were included in the study. The presence and the time of the onset of PLM during the follow-up period were detected by diagnostic imaging (CT-scan, Ultrasound and PET). The OS of patients with and without PLM was compared. Considering the bowel’s layers, the association between depth of bowel involvement, number of PLM, and the relative OS rate was evaluated. ResultsThe median follow-up period was 47.3 (12–138) months. PLM occurred in 24/72 (33.0%) cases; the average onset time of PLM was 13 months. PLM was associated with increased significant mortality risk and an average OS of 33.2 versus 56.8 months (p < 0.001). The risk of developing PLM correlated directly with the depth of bowel involvement. However, there was no statistical difference between the layers in terms of OS at the end of the observational period. ConclusionsPLM occurred more frequently among patients with EOC and bowel involvement. The PLM arose within 15 months of follow-up and the frequency increased according to the depth of involvement. Particularly, the difference is remarkably higher starting from muscular layer where the total number of PLM arose significantly (p = 0.02). Although there was no significant difference among the infiltrated bowel layers in terms of OS, patients with bowel involvement up to muscular had a dramatic reduction in the OS rate during the first 30 months of follow-up.

Ovarian Cancer Metastasis to Lung Parenchyma without Peritoneal Dissemination: A Rare Case

Ovarian cancer is the most lethal gynecological malignancy worldwide. Despite the advances in treatment for ovary cancer, the 5-year survival rate of advanced ovarian cancer patients with peritoneal metastasis remains as high as 30%. Clinical stage is the most important prognostic factor and most patients are at an advanced stage. There is often no clearly identifiable precursor lesion; therefore, the events which lead to metastatic disease are poorly understood. Solitary lung parenchyma metastasis is extremely rare. We report a case of 39-year-old woman who was admitted with a lung mass. She had a history of high-grade serous carcinoma ovary, which was detected and treated 6 years ago with cytoreductive surgery as well ashyperthermic intraperitoneal and adjuvant chemotherapy. During the routine follow-up, positron emission tomography computed tomography scan showed two nodules of soft-tissue density in the lung parenchyma of the left lower lobe with a dimension of 2.8 × 2.5 cm. Intraoperatively, two conglomerated lung nodules seen in lung parenchyma of the left lower lobe. Deeper nodule was in close proximity to the left lower lobe bronchus and left lower lobe pulmonary artery. Video-assisted thoracoscopic surgery was conducted to perform left lower lobectomy. Postoperatively, the patient was stable. Microscopically, the tumor was classified as a high-grade serous carcinoma, and the patient was diagnosed for having an ovarian cancer metastasis. Ovarian cancer rarely metastasizes to the lung parenchyma in a relapse. However, excision of lesion with further chemotherapy showed excellent results. Surgical excision biopsy and intraoperative frozen sectioning, followed by lobectomy or segmentectomy, are both diagnostic and therapeutic.

Prognostic Factors and Survival According to Tumor Subtype in Women With Breast Cancer Brain Metastases

Breast cancer (BC) is the second most cause of central nervous system (CNS) metastases. Studies report that almost one third of patients (pts) with triple-negative, one-third with human epidermal growth factor receptor 2 (HER2)-positive and 15% of those with hormone receptor-positive, HER2-negative metastatic breast cancer will develop brain metastases. It is known that the development of symptomatic brain metastases in women with advanced breast cancer is associated with poor prognosis, irrespective of local and systemic treatments. In the present study, we aim to determine the association between BC subtypes and CNS metastases occurrence and prognosis. Retrospective analysis of 309 BC patients with CNS metastases, confirmed by pathological and/or radiological methods, treated in a Cancer Center between 2003 and 2021, was obtained to identify clinicopathologic factors associated with early onset of brain metastases and survival outcomes. For analysis purposes, 3 BC subtypes were considered according to hormone receptor status and HER-2 expression: ER and/or PR positive, HER-2 positive and triple negative. The median time between diagnosis of BC and detection of CNS metastases was 43 months, and it was significantly shorter in triple negative group (8 months). Twenty-one patients (6,8%) had CNS metastases at BC diagnosis, with CNS being the first site of recurrence in 35,3%, mainly in HER2 positive. Most of the patients had parenchymal metastases (n = 245) and 37 (12%) had leptomeningeal (LM) disease, with predominance in ER and/or PR positive subtype (70,3%). In patients submitted to CNS surgery, the concordance between primary tumor and metastases subtype was higher in triple negative (76,9%) compared to 63,2% in HER-2 positive and 38,9% in ER and/or PR positive group (P < 0.05). After CNS involvement, 25,4% (n = 34) of patients with triple negative disease did not receive any systemic therapy, compared to 30,6% (n = 41) in HER-2 positive and 44% (n = 59) in ER and/or PR positive groups (P = 0.05). Median survival after CNS metastases was 9 months, but significantly longer in HER-2 positive group (16 months) and in patients submitted to surgical resection of CNS metastases, irrespectively of subtype (22 months vs 5 months in other treatment modalities). In multivariate Cox regression analysis, having HER-2 positive tumor was an independent prognostic factor for increasing survival after CNS metastases (HR 0.60, 95% CI: 0.41-0.87, P = 0.007), regardless the therapeutic strategy. Clinical behavior and prognosis of CNS metastases varies according to BC subtype. The association between LM disease and ER and/or PR positive tumors should be explored in upcoming studies. Also, these patients’ prognosis depends on the availability of specific treatment options, therefore, innovative and effective therapeutic approaches are needed, in order to improve survival and quality of life of these patients.

NIMG-07. BEYOND RANDOM AND NUMERIC LESIONS: DIFFERENT IMAGING PATTERNS OF CENTRAL NERVOUS SYSTEM METASTASIS BASED ON PRIMARY TUMOR LOCATION AND MOLECULAR PROFILE

Abstract The purpose of this exhibit is to discuss different imaging patterns of central nervous system (CNS) metastasis based on their primary cancer site and to review the recent literature of the particularities of CNS metastasis distribution in the era of molecular advancement in oncology. Selected cases extracted from our institutions database will be presented. The cases will be didactically organized to illustrate the most common imaging characteristics and distribution of brain metastasis based on their organ of origin, such as lung, breast, renal, skin, testicle and gastrointestinal tract. (SCHROEDER T. et al., J Neurooncol. 2020). We will also discuss the correlation between tumor imaging findings and genetic profile. We intend to review well-known CNS metastasis imaging patterns, as preferential involvement of the posterior fossa and anatomic watershed areas in cases of lung cancer (TAKANO, K. et al. Neuro-Oncology, 2016) and the rarity of parenchyma metastasis from prostate cancer (HATZOGLOU V. et al, J Neuroimaging. 2014). We will also demonstrate newly described imaging findings in correlation with primary tumors genetic mutations, such as higher incidence of leptomeningeal involvement in triple negative breast cancer and increase in the number of brain lesions in cases of EGFR positive lung cancer. Familiarity with the most prevalent imaging characteristics of central nervous system metastasis helps oncologists and radiologists not to miss out a CNS progression in case of a known tumor, and also helps to direct systemic investigation of a primary tumor when brain metastasis is the initial presentation. The correlation between molecular profile and the most common sites of CNS involvement can help on treatment planning, including brain radiation (Yanagihara TK,et al., Tomography. 2017), and also bring to discussion the mechanisms of tumor dissemination, which can be targets for future treatments.

Selected Articles from This Issue

Colony stimulating factor 1 receptor (CSF1R)-dependent cells in the microenvironment (such as macrophages and osteoclasts) contribute to angiogenesis, tumor growth, metastasis, and bone degradation. In this First Disclosure, Smith and colleagues present the characterization of vimseltinib, a selective oral inhibitor of CSF1R in tenosynovial giant cell tumor (TGCT). Vimseltinib depleted macrophages and CSF1R-dependent cells and inhibited tumor growth in preclinical studies. Clinically, the authors present three patients whose CSF1R biomarkers and tumor burden were reduced. Their data supports the continued clinical development of vimseltinib for TGCT.The triple-negative subtyp. of breast cancer (TNBC) carries the highest rate of parenchymal brain metastasis (BrM) and leptomeningeal metastasis (LM). In this manuscript, Deng and colleagues disclose the nitrogen mustard-based compound QBS10072S. QBS10072S delayed tumor growth and reduced leptomeningeal dissemination in a preclinical brain metastasis model. Interestingly, the compound was able to target micro-metastases, which remains a difficult aspect of detecting and treating LM. As the compound was well-tolerated, the continued development of QBS10072S for TNBC LM patients is warranted.Brain metastases occur in approximately 30% of NSCLC patients, leading to significantly worse prognosis. Stereotactic radiotherapy and/or whole brain radiotherapy is currently standard of care for these patients. To increase the effectiveness of radiation therapy in NSCLC brain metastases, Baschnagel and colleagues administered the ATP-competitive ATR inhibitor M6620. M6620 radiosensitized patient-derived xenografts in mice by inhibiting pChk1 and reducing DNA double-strand break (DSB) repair. Ultimately, this resulted in longer overall survival in the preclinical model. Their results support the ongoing phase I clinical study of M6620 in combination with whole brain irradiation (NCT02589522).Adenosine acts as an immunosuppressor by suppressing T cells and dendritic cells and stimulating regulatory T cells. Adenosine is generated in the tumor microenvironment by CD73 from AMP released by cell turnover. In this study, Wurm and colleagues generate a humanized antagonistic CD73 antibody, mAb19. Combining mAb19 with PD-1 inhibition increased T cell activation in vitro. They also demonstrate the combination of mAb19 with the adenosine receptor agonist ADORA3 and doxorubicin, which is known to increase adenosine levels. mAb19 therefore inhibits immunosuppression from the adenosine pathway and is suited for continued development as a cotherapy with immune-targeted or chemotherapy.

Leptomeningeal Disease in Breast Cancer: Pre-Treatment Prognostic Factors and Outcomes

Leptomeningeal disease (LMD) is a devastating diagnosis with limited treatment options and poor prognosis. With recent advances in treatment, women with breast cancer (BC) are living longer and the incidence of LMD in this population is increasing. There remains little data regarding the prognosis and optimal treatment of these patients. As such, we conducted a multi-institutional retrospective review of women with BC LMD and analyzed outcomes based on prognostic factors and treatments.We analyzed the records of women diagnosed with BC LMD via MRIs of their brain and/or spine between 2000 and 2020 at two academic medical centers. Demographic and clinical characteristics were abstracted from electronic medical records and an in-depth radiographic review was performed by a neuro-radiologist for each case. Univariate and multivariate Cox proportional-hazards models were generated to identify factors associated with prolonged survival. Collection and analysis of the data was approved by institutional IRB.We identified 227 women with BC LMD. Prior to developing LMD, most women initially presented with Stage I-III BC (62.1%) with ductal histology (67.0%) and biological subtypes including ER-positive/HER2-negative (56.8%), HER2-positive (17.6%), and triple-negative (22.0%). LMD was first diagnosed a median of 4.6 years (range: 0 to 34.1 years) after the initial diagnosis of BC, and the median age at LMD diagnosis was 54.6 years (range: 29.4 to 84.5 years). At time of LMD diagnosis, 146 (64.3%) women presented with a Karnofsky Performance Status (KPS) ≥ 70, 90 (39.6%) had a preceding parenchymal brain metastasis, and 23 (10.1%) had LMD as their only site of metastatic disease. Radiographically, classical LMD (61.7%) was observed more frequently than nodular-only LMD (13.2%). Brain-only LMD was present in 55.1% of patients, spine-only in 6.1% of patients, and both brain and spine in 38.8% of patients. Median survival from the time of LMD diagnosis was 4.5 months (95% CI: 3.4-7.8). Pre-treatment clinical factors associated with improved survival on univariate analysis included ER-positive/HER2-negative subtype (P = 0.010), KPS ≥ 70 (P < 0.001), LMD as the only site of metastasis (P = 0.004), stable or controlled extracranial metastases (P = 0.042), absence of leukopenia (P = 0.040) and the presence of nodular LMD (P < 0.001). After adjusting for these clinical factors, the receipt of radiation therapy (adjusted hazard ratio [AHR] 0.50, 95% CI: 0.37 - 0.68), systemic therapy (AHR 0.27, 95% CI: 0.19 - 0.38) and intrathecal chemotherapy (AHR 0.49, 95% CI: 0.33 - 0.75) were all associated with improved survival.In one of the largest multi-institutional reviews to date, we found that several pre-treatment clinical factors were significantly associated with improved survival among women with breast cancer LMD. However, despite treatment overall survival remains poor, and there is a need for new, effective therapies.M.G. Milligan: None. A. Aitelli: None. W.A. Mehan: Consultant; Kura Oncology. D.D. Shi: None. D.N. Cagney: Research Grant; Viewray, NhTheraguix. K.S. Oh: None. N. Wang: None. P. Brastianos: Research Grant; Merck, Eli Lily, BMS. Honoraria; Merck, Genentech. Consultant; Angiochem, Dantari Pharmaceuticals, Elevatebio, Eli Lily, Genentech, Pfizer, SK Life Sciences, Tesaro. B. Moy: Research Grant; PUMA biotechnology. N.U. Lin: Research Grant; Genentech, Merck, Pfizer, Seattle Genetics. Consultant; PUMA Biotechnology, Seattle Genetics, Daiichi Sankyo, Astra Zeneca, Denali Therapeutics, California Institute for Regenerative Medicine, Prelude Therapeutics. H.A. Shih: Employee; Dartmouth Hitchcock. Research Grant; AbbVie, NIH. Honoraria; UpToDate. Consultant; Cleveland Clinic. Speaker's Bureau; prIME Oncology. advisory; The Radiosurgery Society. director of clinical operations; Massachusetts General Hospital. clinical operational leader; Massachusetts General Hospital.