Choice of Adjuvant Radiotherapy Facility in Major Salivary Gland Cancer.

OBJECTIVE: Undergoing surgery and adjuvant radiotherapy (aRT) at the same facility has been associated with higher overall survival (OS) in head and neck squamous cell carcinoma. Our study investigates whether undergoing surgery and aRT at the same academic facility is associated with higher OS in major salivary gland cancer (MSGC). METHODS: The 2006-2018 National Cancer Database was queried for patients with MSGC undergoing surgery at an academic facility and then aRT. Multivariable binary logistic and Cox proportional hazards regression models were implemented. RESULTS: Of 2801 patients satisfying inclusion criteria, 2130 (76.0%) underwent surgery and aRT at the same academic facility. Residence in a less populated area (adjusted odds ratio [aOR] 1.69, 95% confidence interval [CI] 1.16-2.45), treatment without adjuvant chemotherapy (aOR 1.97, 95% CI 1.41-2.76), and aRT duration (aOR 1.02, 95% CI 1.01-1.04) were associated with undergoing surgery and aRT at different facilities on multivariable logistic regression adjusting for patient demographics, clinicopathologic features, and adjuvant therapy (p < 0.01). Five-year OS was higher in patients undergoing surgery and aRT at the same academic facility (68.8% vs. 61.9%, p < 0.001). Undergoing surgery and aRT at different facilities remained associated with worse OS on multivariable Cox regression (aHR 1.41, 95% CI 1.10-1.81, p = 0.007). CONCLUSION: Undergoing surgery and aRT at the same academic facility is associated with higher OS in MSGC. Although undergoing surgery and aRT at the same academic facility is impractical for all patients, academic physicians should consider same-facility treatment for complex patients who would most benefit from clear multidisciplinary communication. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Case-Matched Outcomes of Proton Beam and Intensity-Modulated Radiation Therapy for Localized Prostate Cancer.

Purpose: Although both intensity-modulated radiation therapy (IMRT) and proton beam therapy (PBT) offer effective long-term disease control for localized prostate cancer (PCa), there are limited data directly comparing the 2 modalities. Methods: The data from 334 patients treated with conventionally fractionated (79.2 GyRBE in 44 fractions) PBT or IMRT were retrospectively analyzed. Propensity score matching was used to balance factors associated with biochemical failure-free survival (BFFS). Age, race, and comorbidities (not BFFS associates) remained imbalanced after matching. Univariable and covariate-adjusted multivariable (MVA) Cox regression models were used to determine if modality affected BFFS. Results: Of 334 patients, 176 (52.7%) were included in the matched cohort with exact matching to National Comprehensive Cancer Network (NCCN) risk group. With a median follow-up time of 9.0 years (interquartile range [IQR]: 7.8-10.2 years), long-term BFFS was similar between the IMRT and PBT matched arms with 8-year estimates of 85% (95% CI: 76%-91%) and 91% (95% CI: 82%-96%, P = .39), respectively. On MVA, modality was not significantly associated with BFFS in both the unmatched (hazard ratio [HR] = 0.75, 95% CI: 0.35-1.63, P = .47) and matched (HR = 0.87, 95% CI: 0.33-2.33, P = .78) cohorts. Prostate cancer-specific survival (PCSS) and overall survival (OS) were also similar (P > .05). However, in an unmatched analysis, the PBT arm had significantly fewer incidences of secondary cancers within the irradiated field (0.6%, 95% CI: 0.0%-3.1% versus 4.5%, 95% CI: 1.8%-9.0%, P = .028). Conclusions: Both PBT and IMRT offer excellent long-term disease control for PCa, with no significant differences between the 2 modalities in BFFS, PCSS, and OS in matched patients. In the unmatched cohort, fewer incidences of secondary malignancy were noted in the PBT group; however, owing to overall low incidence of secondary cancer and imbalanced patient characteristics between the 2 groups, these data are strictly hypothesis generating and require further investigation.

Cancer Control, Toxicity, and Secondary Malignancy Risks of Proton Radiation Therapy for Stage I-IIB Testicular Seminoma.

Purpose: This study's objective was to report cancer control and toxicity outcomes after proton radiation therapy (RT) in testicular seminoma and to compare secondary malignancy (SMN) risks with photon-based treatment alternatives. Methods and Materials: Consecutive patients with stage I-IIB testicular seminoma treated with proton RT at a single institution were retrospectively analyzed. Kaplan-Meier estimates for disease-free and overall survival were computed. Toxicities were scored using Common Terminology Criteria for Adverse Events version 5.0. Photon comparison plans, including 3-dimensional conformal RT (3D-CRT) and intensity modulated RT (IMRT)/volumetric arc therapy (VMAT), were created for each patient. Dosimetric parameters and SMN risk predictions for different in-field organs-at-risk were compared between the techniques. Excess absolute SMN risks were estimated with organ equivalent dose modeling. Results: Twenty-four patients were included (median age, 38.5 years). The majority of patients had stage II disease (IIA, 12 [50.0%]; IIB, 11 [45.8%]; IA, 1 [4.2%]). Seven (29.2%) and 17 (70.8%) patients had de novo and recurrent disease, respectively (de novo/recurrent: IA, 1/0; IIA, 4/8; IIB, 2/9). Most acute toxicities were mild (grade 1 [G1], 79.2%; G2, 12.5%) with G1 nausea being most common (70.8%). No serious events (G3-5) occurred. With a median follow-up time of 3 years (interquartile range, 2.1-3.6 years), 3-year disease-free and overall survival rates were 90.9% (95% confidence interval, 68.1%-97.6%) and 100% (95% confidence interval, 100%-100%), respectively. There were no documented late toxicities in the follow-up period, including worsening serial creatinine levels suggestive of early nephrotoxicity. Proton RT had significant reductions in mean organ-at-risk doses to the kidneys, stomach, colon, liver, bladder, and body compared with both 3D-CRT and IMRT/VMAT. Proton RT had significantly lower SMN risk predictions compared with 3D-CRT and IMRT/VMAT. Conclusions: Cancer control and toxicity outcomes using proton RT in stage I-IIB testicular seminoma are consistent with existing photon-based RT literature. However, proton RT may be associated with significantly lower SMN risks.

Proton Radiation Therapy After Chemotherapy in the Management of Aggressive Mediastinal Non-Hodgkin Lymphomas: A Particle Therapy Cooperative Group Lymphoma Subcommittee Collaboration.

Purpose: Combined modality therapy with multiagent chemotherapy and radiation therapy is a standard treatment option for aggressive mediastinal non-Hodgkin lymphomas (AMNHLs); however, concerns regarding acute and late radiation toxicities have fueled an effort to use systemic therapy alone. The use of proton therapy (PT) is a promising treatment option, but there are still limited data regarding clinical outcomes with this treatment modality. In this Particle Therapy Cooperative Group lymphoma subcommittee collaboration, we report outcomes of patients with AMNHL treated with pencil-beam scanning PT or double-scatter PT after chemotherapy. Methods and Materials: This was a multi-institutional retrospective observational cohort study of patients with AMNHL treated with PT following chemotherapy between 2011 and 2021. Progression-free survival (PFS), local recurrence-free survival (LRFS), and overall survival (OS) rates were estimated with the Kaplan-Meier method. PT toxicity was graded by the Common Terminology Criteria for Adverse Events version 5.0. A 2-tailed paired t test was used for dosimetric comparisons. Results: Twenty-nine patients were identified. With a median follow-up time of 4.2 years (range, 0.2-8.9 years), the estimated 5-year PFS for all patients was 93%, 5-year LRFS was 96%, and estimated 5-year OS was 87%. Maximum acute grade 1 (G1) toxicities occurred in 18 patients, and 7 patients had maximum G2 toxicities. No G3+ radiation-related toxicities were observed. Average mean lung dose and lung V20 Gy were lower for patients treated with pencil-beam scanning PT compared with double-scatter PT (P = .016 and .006, respectively), while patients with lower mediastinal disease had higher doses for all evaluated dosimetric heart parameters. Conclusions: PT after chemotherapy for patients with AMNHL resulted in excellent outcomes with respect to 5-year PFS, LRFS, and OS without high-grade toxicities. Future work with larger sample sizes is warranted to further elucidate the role of PT in the treatment of AMNHL.

Radiation Therapy for Relapsed or Refractory Diffuse Large B-Cell Lymphoma: What Is the Right Regimen for Palliation?

Purpose: To report objective response rates (ORR), time to local failure (TTLF), and overall survival (OS) among patients with relapsed or refractory diffuse large B-cell lymphoma after salvage- or palliative-intent radiation therapy (RT) and to investigate whether outcomes differed with conventional versus hypofractionated (≥2.5 Gy/fraction) RT. Methods and Materials: A single-institution observational cohort study was performed for patients who completed a course of RT for relapsed or refractory diffuse large B-cell lymphoma between January 1, 2008, and April 1, 2020. Predictors of ORR, TTLF, and OS were calculated using univariable and multivariable regression models. The Kaplan-Meier method was used to estimate TTLF and OS, and log-rank analysis was used to compare outcomes. Equivalent dose in 2 Gy fractions (EQD2) was calculated using an α/ß of 10. Results: One-hundred and sixty-nine patients were treated with 205 RT courses (73 [36%] salvage, 132 [64%] palliative), and hypofractionated RT was used in 100 RT courses (49%). Median RT dose was 30 Gy (range, 8-60 Gy). ORR was 60% for the total cohort (53% and 69% for palliative and salvage cohorts, respectively). Over a median follow-up time of 4 months, median OS in all patients was 5 months (3 and 22 months for palliative and salvage cohorts, respectively). No statistically significant differences in ORR, TTLF, and OS were observed with hypofractionation compared with conventional fractionation. EQD2 ≥35 Gy was associated with improved ORR (odds ratio, 3.79 [1.19-12.03]; P = .024) and prolonged TTLF (0.39 [0.18-0.87]; P = .022), while double-hit receptor status (8.18 [1.08-62.05]; P = .042), cell of origin (3.87 [1.17-8.74]; P = .0012), and bulky disease (≥7.5 cm; 2.12 [1.18-3.81]; P = .012) were associated with inferior TTLF. In the palliative-only cohort, a low-dose regimen of 8 Gy in 2 fractions was associated with similar ORR compared with other fractionation schema but trended towards inferior TTLF (P = .36). Conclusions: Hypofractionation is not associated with differences in disease outcomes for patients with relapsed or refractory diffuse large B-cell lymphoma, while higher RT dose (EQD2 ≥35 Gy) may improve ORR and TTLF. Future work is warranted to elucidate the ideal dose and fractionation schema for such patients who will likely also undergo novel systemic agents and cellular therapies.

Long-term Clinical Outcomes in Favorable Risk Prostate Cancer Patients Receiving Proton Beam Therapy.

Purpose: Long-term data regarding the disease control outcomes of proton beam therapy (PBT) for patients with favorable risk intact prostate cancer (PC) are limited. Herein, we report our institution's long-term disease control outcomes in PC patients with clinically localized disease who received PBT as primary treatment. Methods: One hundred sixty-six favorable risk PC patients who received definitive PBT to the prostate gland at our institution from 2010 to 2012 were retrospectively assessed. The outcomes studied were biochemical failure-free survival (BFFS), biochemical failure, local failure, regional failure, distant failure, PC-specific survival, and overall survival. Patterns of failure were also analyzed. Multivariate Cox proportional hazards modeling was used to estimate independent predictors of BFFS. Results: The median length of follow-up was 8.3 years (range, 1.2-10.5 years). The majority of patients had low-risk disease (58%, n = 96), with a median age of 64 years at the onset of treatment. Of 166 treated men, 13 (7.8%), 8 (4.8%), 2 (1.2%) patient(s) experienced biochemical failure, local failure, regional failure, respectively. Regional failure was seen in an obturator lymph node in 1 patient and the external iliac lymph nodes in the other. None of the patients experienced distant failure. There were 5 (3.0%) deaths, none of which were due to PC. The 5- and 8-year BFFS rate were 97% and 92%, respectively. None of the clinical disease characteristics or treatment-related factors assessed were associated with BFFS on multivariate Cox proportional hazards modeling (all P > .05). Conclusion: Disease control rates reported in our assessment of PBT were similar to those reported in previous clinically localized intact PC analyses, which used intensity-modulated radiotherapy, three-dimensional conformal radiotherapy, or radical prostatectomy as definitive therapy. In addition, BFFS rates were similar, if not improved, to previous PBT studies.

The Safety of Bridging Radiation with Anti-BCMA CAR T-Cell Therapy for Multiple Myeloma.

PURPOSE: B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR) T cells (CART-BCMA) are a promising treatment for relapsed/refractory multiple myeloma (r/rMM). We evaluated the safety and feasibility of bridging radiation (RT) in subjects treated on a phase I trial of CART-BCMA. EXPERIMENTAL DESIGN: Twenty-five r/rMM subjects were treated in three cohorts with two doses of CART-BCMA cells ± cyclophosphamide. We retrospectively analyzed toxicity, response, and CART manufacturing data based on RT receipt. RESULTS: Thirteen subjects received no RT <1 year before CART infusion (Group A). Eight subjects received RT <1 year before CART infusion (Group B) with median time from RT to apheresis of 114 days (range 40-301). Four subjects received bridging-RT (Group C) with a median dose of 22 Gy and time from RT to infusion of 25 days (range 18-35). Group C had qualitatively lower rates of grade 4 (G4) hematologic toxicities (25%) versus A (61.5%) and B (62.5%). G3-4 neurotoxicity occurred in 7.7%, 25%, and 25% in Group A, B, and C, respectively. G3-4 cytokine release syndrome was observed in 38.5%, 25%, and 25% in Group A, B, and C, respectively. Partial response or better was observed in 54%, 38%, and 50% of Group A, B, and C, respectively. RT administered <1 year (P = 0.002) and <100 days (P = 0.069) before apheresis was associated with lower in vitro proliferation during manufacturing; however, in vivo CART-BCMA expansion appeared similar across groups. CONCLUSIONS: Bridging-RT appeared safe and feasible with CART-BCMA therapy in our r/rMM patients, though larger future studies are needed to draw definitive conclusions.

Radiation Therapy for Plasma Cell Disease of the Brain and Skull: Poor Palliation and Survival After Treatment for Central Nervous System Involvement.

PURPOSE: Myeloma lesions of the head can present with central nervous system (CNS) involvement (leptomeningeal disease or brain metastasis), cranial neuropathy (CN), or impending neurologic involvement (INI). We analyzed response and survival after palliative radiation therapy (RT) to the brain and/or skull for myeloma lesions to determine whether CNS involvement fared worse than other RT indications. METHODS AND MATERIALS: We retrospectively analyzed 54 palliative RT courses administered at our institution from 2008 to 2019. Eleven courses were administered for CNS disease, 28 for CN, and 15 for INI. Demographic, disease, and RT variables were recorded as well as clinical response, radiographic response, and survival. Univariate analyses were performed for differences between groups, effects of clinical and RT treatment factors on response, as well as dose response. Survival was analyzed with the Kaplan-Meier method and compared by the log-rank test. RESULTS: This heavily pretreated cohort received a median of 20 to 24 Gy, most often to the base of skull, orbit(s), calvarium, or whole brain. Any clinical response (partial or complete vs no response or progressive disease) was significantly more likely for patients with CN and INI when collectively compared with patients with CNS disease (P < .001). Dose response was significant for doses ≥15 and 20 Gy for the whole cohort (P = .026 and .005, respectively) and patients with CN/INI (P = .023 and .002, respectively). Additionally, patients with high-risk cytogenetics were less likely to clinically respond (P = .009). Patients with CNS disease had worse survival (P = .005). CONCLUSIONS: Patients with leptomeningeal disease/brain metastasis have poor clinical response and survival after RT and their responses do not demonstrate a dose response. Given these poor outcomes, the potential benefit of RT may be limited for some patients who may be alternatively managed by supportive care or short RT courses. Patients with CN/INI have longer survival and better response rates and may benefit from RT courses ≥15 to 20 Gy.

Contemporary treatment of keloids: A 10-year institutional experience with medical management, surgical excision, and radiation therapy.

INTRODUCTION: We evaluate a single center's, decade-long experience utilizing 3 approaches to keloid treatment: corticosteroid medical management (MM), surgical excision (SE), and surgical excision + radiation therapy (SE + RT). STUDY DESIGN: Patients undergoing keloid treatment were identified (2008-2017). Outcomes were symptomatology/cosmesis for MM, and recurrence and complications for SE and SE + RT. Logistic regression was used to determine factors associated with recurrence and complications. RESULTS: 284 keloids (95 MM, 94 SE, 95 S E + RT) corresponded to patients with a median age of 39.1 (IQR: 26.1-53), 68.1% Black, and followed-up for 15.4 months (IQR: 5.6-30.7). For MM, 84.6% and 72.5% reported improvement in cosmesis and symptoms, respectively. SE and SE + RT recurrence were 37.2 and 37.9%, respectively. In adjusted analyses, higher radiation doses were associated with decreased recurrence whereas male gender (OR 3.3) and postoperative steroids (OR 9.5) were associated with increased recurrence (p < 0.01). There were more complications in the SE + RT group. CONCLUSIONS: MM resulted in at least some improvement. Recurrence rates after SE and SE + RT were similar. Female sex is protective, race does not affect outcomes.

Initial clinical experience treating patients with palliative radiotherapy for malignant pleural mesothelioma on the HalcyonTM linear accelerator.

BACKGROUND: Radiation therapy (RT) can provide effective symptomatic palliation in patients with malignant pleural mesothelioma (MPM). Advances in RT technology, including intensity-modulated RT (IMRT) and volumetric-modulated arc therapy (VMAT), have improved treatment conformality, potentially improving the therapeutic ratio of RT. A novel 6-MV flattening-filter-free O-ring linear accelerator, HalcyonTM (Varian Medical Systems, Palo Alto, CA, USA), was built to provide such advanced therapies, while possibly reducing treatment time. Here, we report the initial clinical experience using HalcyonTM to deliver palliative RT for patients with MPM. METHODS: We retrospectively assessed consecutive patients with MPM who received thoracic RT on HalcyonTM. Their electronic medical records were reviewed for clinical, RT planning, treatment timing, and image-guidance RT (IGRT) data. RESULTS: Four patients with metastatic MPM received palliative RT on HalcyonTM between 1/2017-1/2020 for severe pain (50%), dysphagia (25%), or dyspnea (25%). Targets included a combination of pleura, chest wall, lung, hilum, and mediastinum, with patient-specific dose and fractionation regimens ranging from 20-45 Gy in 5-15 fractions, and 75% of patients receiving concurrent systemic therapy. Pre-specified target and organ-at-risk constraints were met for nearly all plans. At a median follow-up of 2.2 months (range, 1.6-7.1 months), all patients experienced either improved (75%) or stable (25%) tumor-related symptoms following palliative RT. The mean 3D vector couch correction was 0.67±0.15 cm. The mean beam-on, treatment (beam-on plus cone-beam computed tomography times), and approximated total room usage times were 1.6±0.2, 1.8±0.2, and 9.8±0.2 min, respectively. Grade 2 fatigue and cough occurred in 25% and 25% of patients, and no patients experienced Grade ≥3 toxicity. CONCLUSIONS: In this initial clinical experience treating patients with palliative RT for MPM on HalcyonTM, treatment provided symptom palliation and local control across multiple palliative scenarios, with minimal toxicity, acceptable dosimetry, and setup corrections and treatment times that compared favorably with other published experiences of MPM RT. Palliative RT on HalcyonTM can provide patients with MPM quick and safe tumor-related symptom relief, even in a frail, elderly population.

Scalp Invasion by Atypical or Anaplastic Meningioma Is a Risk Factor for Development of Systemic Metastasis.

BACKGROUND: Atypical and anaplastic meningiomas (AAMs) are rare and comprise approximately 5% of all meningiomas. Extracranial metastases in meningioma patients occur in 0.1% of all cases, but these lesions are difficult to treat and may be a poor prognostic factor. METHODS: We conducted a retrospective chart review between 1990 and 2016 of patients who had surgical resection of AAM. In a cohort of 149 patients, 6 had metastatic lesions that were histologically confirmed to be meningioma. We compared baseline characteristics between patients with and without metastasis and performed a multivariate Cox regression analysis to assess risk factors for the development of systemic metastasis. RESULTS: Six patients had histologically confirmed meningioma metastasis. We hypothesized that the presence of scalp invasion in patients could be a potential risk factor for the development of systemic meningioma metastasis. Nine out of the 149 patients without metastasis had scalp invasion, whereas 4 out of the 6 patients with metastasis had scalp invasion. Patients with metastasis had a median age of 62 ± 20. Patients without metastasis had a median age of 59 ± 15 years. Gender distribution was similar; approximately 50% of patients in each group were female. Eighty-five percent of patients with metastatic disease were white, and 65% of patients without metastatic disease were white. Among patients without metastatic disease, 77% had World Health Organization II tumors, whereas 50% of patients with metastatic disease had World Health Organization II tumors. In multivariate analysis including age, tumor grade, size, location, extent of resection, sex, and scalp invasion, the only significant predictor of systemic metastasis was scalp invasion (odds ratio = 39.67; 95% confidence interval = 3.74-421.12; P = 0.0023). Median overall survival (OS) with metastasis was 126 months, and median OS without metastasis was 158 months. Having metastatic disease was not significantly associated with worse OS (P = 0.33). CONCLUSIONS: Metastasis development from AAM is a rare but serious event. Because scalp invasion is a strongly associated predictive factor for development of systemic metastasis in patients with AAM, it is necessary to consider strategies to prevent and to be vigilant of the development of scalp invasion.

In Vivo Bioluminescence Tomography Center of Mass-Guided Conformal Irradiation.

PURPOSE: The cone-beam computed tomography (CBCT)-guided small animal radiation research platform (SARRP) has provided unique opportunities to test radiobiologic hypotheses. However, CBCT is less adept to localize soft tissue targets growing in a low imaging contrast environment. Three-dimensional bioluminescence tomography (BLT) provides strong image contrast and thus offers an attractive solution. We introduced a novel and efficient BLT-guided conformal radiation therapy and demonstrated it in an orthotopic glioblastoma (GBM) model. METHODS AND MATERIALS: A multispectral BLT system was integrated with SARRP for radiation therapy (RT) guidance. GBM growth curve was first established by contrast CBCT/magnetic resonance imaging (MRI) to derive equivalent sphere as approximated gross target volume (aGTV). For BLT, mice were subject to multispectral bioluminescence imaging, followed by SARRP CBCT imaging and optical reconstruction. The CBCT image was acquired to generate anatomic mesh for the reconstruction and RT planning. To ensure high accuracy of the BLT-reconstructed center of mass (CoM) for target localization, we optimized the optical absorption coefficients µa by minimizing the distance between the CoMs of BLT reconstruction and contrast CBCT/MRI-delineated GBM volume. The aGTV combined with the uncertainties of BLT CoM localization and target volume determination was used to generate estimated target volume (ETV). For conformal irradiation procedure, the GBM was first localized by the predetermined ETV centered at BLT-reconstructed CoM, followed by SARRP radiation. The irradiation accuracy was qualitatively confirmed by pathologic staining. RESULTS: Deviation between CoMs of BLT reconstruction and contrast CBCT/MRI-imaged GBM is approximately 1 mm. Our derived ETV centered at BLT-reconstructed CoM covers >95% of the tumor volume. Using the second-week GBM as an example, the ETV-based BLT-guided irradiation can cover 95.4% ± 4.7% tumor volume at prescribed dose. The pathologic staining demonstrated the BLT-guided irradiated area overlapped well with the GBM location. CONCLUSIONS: The BLT-guided RT enables 3-dimensional conformal radiation for important orthotopic tumor models, which provides investigators a new preclinical research capability.

Genome-wide investigation of intragenic DNA methylation identifies ZMIZ1 gene as a prognostic marker in glioblastoma and multiple cancer types.

DNA methylation has long been recognized as a tumor-promoting factor when aberrantly regulated in the promoter region of genes. However, the effect of intragenic DNA methylation remains poorly understood on the clinical aspects of cancer. Here, we first evaluated the significance of intragenic DNA methylation for survival outcomes of cancer patients in a genome-wide manner. Glioblastoma patients with hypermethylated intragenic regions exhibited better survival than hypomethylated patients. Enrichment analyses of intragenic DNA methylation profiles with epigenetic signatures prioritized the intragenic DNA methylation of ZMIZ1 as a possible glioblastoma prognostic marker that is independent of MGMT methylation in IDH1 wild-type patients. This intragenic region harbored molecular signatures of alternative transcription across many cell types. Furthermore, we found that the intragenic region of ZMIZ1 can serve as a molecular marker in multiple cancers including astrocytomas, bladder cancer and renal cell carcinoma according to DNA methylation status. Finally, in vitro and in vivo experiments uncovered the role of ZMIZ1 as a driver of tumor cell migration. Altogether, our results identify ZMIZ1 as a prognostic marker in cancer and highlight the clinical significance of intragenic methylation in cancer.

Combination anti-CXCR4 and anti-PD-1 immunotherapy provides survival benefit in glioblastoma through immune cell modulation of tumor microenvironment.

BACKGROUND: Emerging evidence suggests that myeloid cells play a critical role in glioblastoma (GBM) immunosuppression. Disappointing results of recent checkpoint inhibitor trials suggest that combination immunotherapy with alternative agents could be fruitful in overcoming immunosuppression. Overexpression of chemokine receptor CXCR4 is associated with poor prognosis in GBM. We investigate the treatment effects of combination immunotherapy with anti-PD-1 and anti-CXCR4 in a murine glioma model. METHODS: C57BL/6 mice were implanted with GL261-Luc+ glioma cells and randomized into 4 arms: (1) control (2) anti-PD-1 (3) anti-CXCR4, and (4) anti-PD-1 and anti-CXCR4 therapy. Overall survival and median survival were assessed. Cell populations were assessed by flow cytometry. RESULTS: Combination therapy conferred a significant survival benefit compared to control and monotherapy arms. Mice that received combination therapy demonstrated immune memory and decreased populations of immunosuppressive tumor-infiltrating leukocytes, such as monocytic myeloid-derived suppressor cells and microglia within the brain. Furthermore, combination therapy improved CD4+/CD8+ ratios in the brain as well as contributed to increased levels of pro-inflammatory cytokines. CONCLUSIONS: Anti-CXCR4 and anti-PD-1 combination immunotherapy modulates tumor-infiltrating populations of the glioma microenvironment. Targeting myeloid cells with anti-CXCR4 facilitates anti-PD-1 to promote an antitumor immune response and improved survival rates.

Contrasting impact of corticosteroids on anti-PD-1 immunotherapy efficacy for tumor histologies located within or outside the central nervous system.

Immune checkpoint blockade targeting programmed cell death protein 1 (PD-1) is emerging as an important treatment strategy in a growing list of cancers, yet its clinical benefits are limited to a subset of patients. Further investigation of tumor-intrinsic predictors of response and how extrinsic factors, such as iatrogenic immunosuppression caused by conventional therapies, impact the efficacy of anti-PD-1 therapy are paramount. Given the widespread use of corticosteroids in cancer management and their immunosuppressive nature, this study sought to determine how corticosteroids influence anti-PD-1 responses and whether their effects were dependent on tumor location within the periphery versus central nervous system (CNS), which may have a more limiting immune environment. In well-established anti-PD-1-responsive murine tumor models, corticosteroid therapy resulted in systemic immune effects, including severe and persistent reductions in peripheral CD4+ and CD8 + T cells. Corticosteroid treatment was found to diminish the efficacy of anti-PD-1 therapy in mice bearing peripheral tumors with responses correlating with peripheral CD8/Treg ratio changes. In contrast, in mice bearing intracranial tumors, corticosteroids did not abrogate the benefits conferred by anti-PD-1 therapy. Despite systemic immune changes, anti-PD-1-mediated antitumor immune responses remained intact during corticosteroid treatment in mice bearing intracranial tumors. These findings suggest that anti-PD-1 responses may be differentially impacted by concomitant corticosteroid use depending on tumor location within or outside the CNS. As an immune-specialized site, the CNS may potentially play a protective role against the immunosuppressive effects of corticosteroids, thus sustaining antitumor immune responses mediated by PD-1 blockade.

Outcomes of Metastatic Brain Lesions Treated with Radioactive Cs-131 Seeds after Surgery: Experience from One Institution.

Introduction Brain metastases are common in patients with advanced systemic cancer and often recur despite treatment with surgical resection and radiotherapy. Whole brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) have significantly improved local control rates but are limited by complications including neurocognitive deficits and radiation necrosis. These risks can be higher in the re-irradiation setting. Brachytherapy may be an alternative method of additional targeted adjuvant radiotherapy with acceptable rates of toxicity. Methods A retrospective chart review of all patients undergoing resection for metastatic brain lesions and permanent low-dose rate Cs-131 brachytherapy was performed for one institution over a 10-year period. All patients had previous radiation therapy already and, after surgery, were followed with imaging every three months. Patient demographics, disease characteristics, intracranial disease, peri- and post-operative complications, and outcomes were recorded. The primary outcome of interest was local tumor recurrence at the site of brachytherapy while secondary outcomes included distant disease progression (within the brain) and complications such as radiation necrosis. Results During the study period, nine cases of individual patients met inclusion criteria. The median preoperative lesion diameter was 3 cm (0.8-4.1). The median overall survival after surgery and brachytherapy was 10.3 months, after excluding two patients who were lost to follow-up. Six of nine patients had no local recurrence, while three patients had development or progression of distant lesions. No patients experienced acute or delayed complications. Conclusion Cs-131 brachytherapy is a promising alternative method for controlling brain metastases after previous radiation interventions and surgical resection. In this case series, there were no incidences of local tumor recurrence or complications such as radiation necrosis.

TIGIT and PD-1 dual checkpoint blockade enhances antitumor immunity and survival in GBM.

The use of inhibitory checkpoint blockade in the management of glioblastoma has been studied in both preclinical and clinical settings. TIGIT is a novel checkpoint inhibitor recently discovered to play a role in cancer immunity. In this study, we sought to determine the effect of anti-PD-1 and anti-TIGIT combination therapy on survival in a murine glioblastoma (GBM) model, and to elucidate the underlying immune mechanisms. Using mice with intracranial GL261-luc+ tumors, we found that TIGIT expression was upregulated on CD8+ and regulatory T cells (Tregs) in the brain compared to draining cervical lymph nodes (CLN) and spleen. We then demonstrated that treatment using anti-PD-1 and anti-TIGIT dual therapy significantly improved survival compared to control and monotherapy groups. The therapeutic effect was correlated with both increased effector T cell function and downregulation of suppressive Tregs and tumor-infiltrating dendritic cells (TIDCs). Clinically, TIGIT expression on tumor-infiltrating lymphocytes was shown to be elevated in patient GBM samples, suggesting that the TIGIT pathway may be a valuable therapeutic target. Expression of the TIGIT ligand, PVR, further portended a poor survival outcome in patients with low-grade glioma. We conclude that anti-TIGIT is an effective treatment strategy against murine GBM when used in combination with anti-PD-1, improving overall survival via modifications of both the T cell and myeloid compartments. Given evidence of PVR expression on human GBM cells, TIGIT presents as a promising immune therapeutic target in the management of these patients.

Adjuvant radiotherapy and outcomes of presumed hemorrhagic melanoma brain metastases without malignant cells.

BACKGROUND: Patients with melanoma can present with a hemorrhagic intracranial lesion. Upon resection, pathology reports may not detect any malignant cells. However, the hemorrhage may obscure their presence and so physicians may still decide whether adjuvant radiotherapy should be applied. Here, we report on the outcomes of a series of patients with melanoma with hemorrhagic brain lesions that returned with no tumor cells. METHODS: All melanoma patients who had craniotomies from 2008 to 2017 at a single institution for hemorrhagic brain lesions were identified through retrospective chart review. Those who had pathology reports with no malignant cells were analyzed. Recurrence at the former site of hemorrhage and resection was the primary outcome. RESULTS: Ten patients met inclusion criteria, and the median follow-up time was 8.5 (1.8-27.3) months. At the time of craniotomy, the median number of brain lesions was 3 (1-25). Two patients had prior craniotomies, eight had prior radiation, and six had prior immunotherapy to the lesion of interest. After surgery, one patient received stereotactic radiosurgery (SRS) to the resection bed. Only one patient developed subsequent melanoma at the resection site; this patient developed the lesion recurrence once and had not received postoperative SRS. CONCLUSION: Although small foci of metastatic disease as a source of bleeding for some patients cannot be excluded, melanoma patients with a suspected hemorrhagic brain metastasis that shows no tumor cells on pathology may benefit from close observation. The local recurrence risk in such cases appears to be low, even without adjuvant radiation.

Population-based Study Determining Predictors of Cancer-Specific Mortality and Survival in Pediatric High-grade Brainstem Glioma.

BACKGROUND: Pediatric high-grade brainstem gliomas are aggressive tumors with dismal prognoses. Large-scale studies are needed to further characterize these tumors and determine factors influencing cancer-specific mortality and survival at varying time points. METHODS: We used the SEER (Surveillance Epidemiology and End Results) database to conduct a population-based study of pediatric patients with histologically confirmed anaplastic astrocytoma or glioblastoma tumors located within the brainstem. Multivariate analyses incorporating patient demographics, tumor characteristics, and treatments were used to determine predictors of cancer-specific mortality and survival at 6 months, 9 months, 1 year, and 2 years. RESULTS: We included 154 patients from the SEER database: 72 patients with anaplastic astrocytoma (47%) and 82 (53%) with glioblastoma. Median survival for the entire cohort was 10.0 months. Glioblastoma histology, developmental stage, and large tumor size were significantly associated with cancer-specific mortality. Six-month, 9-month, 1-year, and 2-year survival was 75%, 57%, 42%, and 20%, respectively. Glioblastoma histology was associated with worsened survival at 6 months (odds ratio [OR], 0.19; P = 0.0081), 9 months (OR, 0.18; P < 0.001), 1 year (OR, 0.19; P < 0.001), and 2 years (OR, 0.14; P = 0.0055). Radiation therapy was associated with improved survival at 6 (OR, 8.53; P = 0.0012) and 9 months (OR, 3.58; P = 0.035) but not at 1 or 2 years. Radiation therapy was associated with improved survival in glioblastoma (9.0 vs. 3.0 months; P < 0.001). CONCLUSIONS: This population-based study showed that glioblastoma histology is associated with a poor prognosis in pediatric patients with high-grade brainstem gliomas. Regardless of histology, radiation therapy improved survival at 6 and 9 months but not long-term.

Dendritic cell activation enhances anti-PD-1 mediated immunotherapy against glioblastoma.

INTRODUCTION: The glioblastoma (GBM) immune microenvironment is highly suppressive as it targets and hinders multiple components of the immune system. Checkpoint blockade (CB) is being evaluated for GBM patients. However, biomarker analyses suggest that CB monotherapy may be effective only in a small fraction of GBM patients. We hypothesized that activation of antigen presentation would increase the therapeutic response to PD-1 blockade. RESULTS: We show that activating DCs through TLR3 agonists enhances the anti-tumor immune response to CB and increases survival in GBM. Mice treated with TLR3 agonist poly(I:C) and anti-PD-1 demonstrated increased DC activation and increased T cell proliferation in tumor draining lymph nodes. We show that DCs are necessary for the improved anti-tumor immune response. CONCLUSIONS: This study suggests that augmenting antigen presentation is an effective multimodal immunotherapy strategy that intensifies anti-tumor responses in GBM. Specifically, these data represent an expanded role for TLR3 agonists as adjuvants to CB. METHODS: Using a preclinical model of GBM, we tested the efficacy of combinatorial immunotherapy with anti-PD-1 and TLR3 agonist, poly(I:C). Characterization of the immune response in tumor infiltrating immune cells and in secondary lymphoid organs was performed. Additionally, dendritic cell (DC) depletion experiments were performed.