Impact of Race on Outcomes of High-Risk Patients With Prostate Cancer Treated With Moderately Hypofractionated Radiotherapy in an Equal Access Setting.

Background: Moderately hypofractionated radiotherapy (MHRT) is an accepted treatment for localized prostate cancer; however, limited MHRT data address high-risk prostate cancer (HRPC) and/or African American patients. We report clinical outcomes and toxicity profiles for individuals with HRPC treated in an equal access system. Methods: We identified patients with HRPC treated with MHRT at a US Department of Veterans Affairs referral center. Exclusion criteria included < 12 months follow-up and elective nodal irradiation. MHRT included 70 Gy over 28 fractions or 60 Gy over 20 fractions. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicities were graded using Common Terminology Criteria for Adverse Events, version 5.0. Clinical endpoints, including biochemical recurrence-free survival (BRFS), distant metastases-free survival (DMFS), overall survival (OS), and prostate cancer-specific survival (PCSS) were estimated using Kaplan-Meier methods. Clinical outcomes, acute toxicity, and late toxicity-free survival were compared between African American and White patients with logistic regression and log-rank testing. Results: Between November 2008 and August 2018, 143 patients with HRPC were treated with MHRT and followed for a median of 38.5 months; 82 (57%) were African American and 61 were White patients. Concurrent androgen deprivation therapy (ADT) was provided for 138 (97%) patients for a median duration of 24 months. No significant differences between African American and White patients were observed for 5-year OS (73% [95% CI, 58%-83%] vs 77% [95% CI, 60%-97%]; P = .55), PCSS (90% [95% CI, 79%-95%] vs 87% [95 % CI, 70%-95%]; P = .57), DMFS (91% [95% CI, 80%-96%] vs 81% [95% CI, 62%-91%]; P = .55), or BRFS (83% [95% CI, 70%-91%] vs 71% [95% CI, 53%-82%]; P = .57), respectively. Rates of acute grade 3+ GU and GI were low overall (4% and 1%, respectively). Late toxicities were similarly favorable with no significant differences by race. Conclusions: Individuals with HRPC treated with MHRT in an equal access setting demonstrated favorable clinical outcomes that did not differ by race, alongside acceptable rates of acute and late toxicities.

Prognostic Model for Intracranial Progression after Stereotactic Radiosurgery: A Multicenter Validation Study.

Stereotactic radiosurgery (SRS) is a standard of care for many patients with brain metastases. To optimize post-SRS surveillance, this study aimed to validate a previously published nomogram predicting post-SRS intracranial progression (IP). We identified consecutive patients completing an initial course of SRS across two institutions between July 2017 and December 2020. Patients were classified as low- or high-risk for post-SRS IP per a previously published nomogram. Overall survival (OS) and freedom from IP (FFIP) were assessed via the Kaplan−Meier method. Assessment of parameters impacting FFIP was performed with univariable and multivariable Cox proportional hazard models. Among 890 patients, median follow-up was 9.8 months (95% CI 9.1−11.2 months). In total, 47% had NSCLC primary tumors, and 47% had oligometastatic disease (defined as ≤5 metastastic foci) at the time of SRS. Per the IP nomogram, 53% of patients were deemed high-risk. For low- and high-risk patients, median FFIP was 13.9 months (95% CI 11.1−17.1 months) and 7.6 months (95% CI 6.4−9.3 months), respectively, and FFIP was superior in low-risk patients (p < 0.0001). This large multisite BM cohort supports the use of an IP nomogram as a quick and simple means of stratifying patients into low- and high-risk groups for post-SRS IP.

Patterns of recurrence after intracranial stereotactic radiosurgery for brain-only metastases from non-small cell lung cancer and the impact of upfront thoracic therapy with synchronous presentation.

Background: We characterized long-term organ-specific patterns of recurrence, time to progression (TTP) and overall survival (OS) in patients with non-small cell lung cancer (NSCLC) with brain-only metastases treated with single-fraction stereotactic radiosurgery (SRS) and analyzed the impact of upfront thoracic therapy (UTT) in those with synchronous presentation of primary NSCLC and brain metastases. Methods: The clinical records of 137 patients with brain metastases from NSCLC treated with intracranial SRS, and no other metastatic sites, were retrospectively reviewed. Patients with available follow-up imaging (n=124) were analyzed for patterns of recurrence; all were analyzed for OS. Results: The majority of first distant recurrences were in brain and thoracic sites, while extra-thoracic sites were relatively uncommon. After median follow-up of 16.0 months, 24.8% did not develop recurrence outside of brain and/or thoracic sites and 43.5% were free of distant extracranial recurrence. Whole brain radiotherapy (WBRT) and UTT, but not systemic therapy, altered patterns of recurrence and intracranial or extracranial TTP. Multivariable analysis revealed UTT, but not systemic therapy or WBRT, was associated with more favorable OS [hazard ratio (HR) 0.515, P=0.029] among 88 patients with synchronous presentation. Within the subgroup of thoracic stage III patients (n=69), those treated with UTT experienced remarkable median extracranial TTP and OS of 19.3 and 22.7 months, respectively. Conclusions: First and cumulative recurrences in patients treated with intracranial SRS for NSCLC metastases limited to brain are most often in the brain and thorax. Long-term survival is possible, regardless of thoracic stage, and is dependent on UTT among other factors.

Effect of Large Prostate Volume on Efficacy and Toxicity of Moderately Hypofractionated Radiation Therapy in Patients With Prostate Cancer.

Purpose: To evaluate the effect of prostate volume on outcomes after moderately hypofractionated radiation therapy (mHFRT) for prostate cancer. Methods and Materials: Prostate cancer patients treated with mHFRT at a Veteran's Affairs Medical Center from August 20, 2008, to January 31, 2018, were identified. Patients were placed into a large prostate planning target volume (LPTV) cohort if their prostate PTV was in the highest quartile. Acute/late genitourinary (GU) and gastrointestinal toxicity events among patients with and without LPTV were compared. Multivariable analyses estimated the effect of factors on toxicity. Overall survival, biochemical recurrence-free survival, and freedom from late GU/gastrointestinal toxicity of patients with and without LPTV were estimated via Kaplan-Meier. Results: Four hundred and seventy-two patients were included. Ninety-three percent received 70 Gy in 2.5 Gy fractions; 75% received androgen deprivation therapy. Median follow-up was 69 months. Patients with LPTV (PTV >138.4 cm3) had a higher late 2 + GU toxicity compared with those without (59% vs 48%, P = .03). Earlier time to late 2 + GU toxicity was associated with LPTV (hazard ratio 1.36; 95% confidence interval [CI], 1.00-1.86; P = .047), androgen deprivation therapy use (hazard ratio 1.60; 95% CI, 1.13-2.27; P = .01), and higher baseline American Urologic Association symptom score (odds ratio 1.03; 95% CI, 1.02-1.05; P < .001). At 2 years, freedom from late 2 + GU toxicity was 46% (95% CI, 47%-54%) for those with LPTV versus 61% (95% CI, 55%-65%) for those without (P = .04). Late grade 3 GU toxicity was 7% for those with LPTV and 4% for those without. No differences in overall survival or biochemical recurrence-free survival were observed between patients with or without LPTV. Conclusions: LPTV did not affect efficacy of mHFRT for prostate cancer; however, it was associated with increased risk and earlier onset of late grade 2 + GU toxicity.

Effective Pain Control With Very Low Dose Palliative Radiation Therapy for Patients With Multiple Myeloma With Uncomplicated Osseous Lesions.

BACKGROUND: Osteolytic lesions are present in 75% of patients with multiple myeloma (MM) and frequently require palliation with radiation therapy (RT). Prior case series of patients with MM with bone pain undergoing palliative RT suggests doses ≥12 Gy (equivalent dose in 2Gy fractions, EQD2) provide excellent bone pain relief. However, recent advances in care and novel biologic agents have significantly improved overall survival and quality of life for patients with MM. We hypothesized that lower-dose RT (LDRT, EQD2 <12 Gy) offers an effective alternative to higher-dose RT (HDRT, EQD2 ≥12 Gy) for palliation of painful, uncomplicated MM bone lesions. METHODS: We retrospectively identified patients with MM treated with RT for uncomplicated, painful bone lesions and stratified by EQD2 ≥/< 12 Gy. Clinical pain response (CPR) rates, acute and late toxicity, pain response duration, and retreatment rates between LDRT and HDRT groups were analyzed. RESULTS: Thirty-five patients with 70 treated lesions were included: 24 patients (48 lesions) treated with HDRT and 11 patients (22 lesions) with LDRT. Median follow-up was 14 and 16.89 months for HDRT and LDRT, respectively. The median dose of HDRT treatment was 20 Gy versus 4 Gy in the LDRT group. The CPR rate was 98% for HDRT and 95% for LDRT. There was no significant difference in any-grade acute toxicity between the HDRT and LDRT cohorts (24.5% vs 9.1%, Χ2 P = .20). Pain recurred in 10% of lesions (12% HDRT vs 9.5% LDRT). Median duration of pain response did not significantly differ between cohorts (P = .91). Five lesions were retreated, 2 (9.5%) in the LDRT cohort, and 3 (6.3%) in the HDRT cohort. CONCLUSION: In this study, LDRT effectively palliated painful, uncomplicated MM bony lesions with acceptable CPR and duration of palliation. These data support prospective comparisons of LDRT versus HDRT for palliation of painful, uncomplicated MM bony lesions.

Development and Implementation of an Educational Simulation Workshop in Fiberoptic Laryngoscopy for Radiation Oncology Residents.

PURPOSE: Fiberoptic laryngoscopy (FOL) is a critical tool for the diagnosis, staging, assessment of treatment response, and detection of recurrence for head and neck (H&N) malignancies. No standardized recommendations exist for procedural FOL education in radiation oncology. We therefore implemented a pilot simulation workshop to train radiation oncology residents in pertinent H&N anatomy and FOL technique. METHODS AND MATERIALS: A 2-phase workshop and simulation session was designed. Residents initially received a lecture on H&N anatomy and the logistics of the FOL examination. Subsequently, residents had a practical session in which they performed FOL in 2 simulated environments: a computerized FOL program and mannequin-based practice. Site-specific attending physicians were present to provide real-time guidance and education. Pre- and postworkshop surveys were administered to the participants to determine the impact of the workshop. Subsequently, postgraduate year (PGY)-2 residents were required to complete 6 supervised FOL examinations in clinic and were provided immediate feedback. RESULTS: Annual workshops were performed in 2017 to 2019. The survey completion rate was 14 of 18 (78%). Participants ranged from fourth-year medical students to PGY-2 to PGY-5 residents. All PGY-2 residents completed their 6 supervised FOL examinations. On a 5-point Likert scale, mean H&N anatomy knowledge increased from 2.4 to 3.7 (standard deviation = 0.6, P < .0001). Similarly, mean FOL procedural skill confidence increased from 2.2 to 3.3 (standard deviation = 0.7, P < .0001). These effects were limited to novice (fourth-year medical students to PGY-2) participants. All participants found the exercise clinically informative. CONCLUSIONS: A simulation-based workshop for teaching FOL procedural skills increased confidence and procedural expertise of new radiation oncology residents and translated directly to supervised clinical encounters. Adoption of this type of program may help to improve resident training in H&N cancer.

Multi-Institutional Analysis of Synchronous Prostate and Rectosigmoid Cancers.

Purpose: To perform a multi-institutional analysis of patients with synchronous prostate and rectosigmoid cancers. Materials and Methods: A retrospective review of Duke University and Durham Veterans Affairs Medical Center records was performed for men with both prostate and rectosigmoid adenocarcinomas from 1988 to 2017. Synchronous presentation was defined as symptoms, diagnosis, or treatment of both cancers within 12 months of each other. The primary study endpoint was overall survival. Univariate and multivariable Cox regression was performed. Results: Among 31,883 men with prostate cancer, 330 (1%) also had rectosigmoid cancer and 54 (16%) of these were synchronous. Prostate cancer was more commonly the initial diagnosis (59%). Fifteen (28%) underwent prostatectomy or radiotherapy before an established diagnosis of rectosigmoid cancer. Stage I, II-III, or IV rectosigmoid cancer was present in 26, 57, and 17% of men, respectively. At a median follow-up of 43 months, there were 18 deaths due rectosigmoid cancer and two deaths due to prostate cancer. Crude late grade ≥3 toxicities include nine (17%) gastrointestinal and six (11%) genitourinary. Two anastomotic leaks following low anterior resection occurred in men who received a neoadjuvant radiotherapy prostate dose of 70.6-76.4 Gy. Rectosigmoid cancer stages II-III (HR 4.3, p = 0.02) and IV (HR 16, p < 0.01) as well as stage IV prostate cancer (HR 31, p < 0.01) were associated with overall survival on multivariable analysis. Conclusions: Synchronous rectosigmoid cancer is a greater contributor to mortality than prostate cancer. Men aged ≥45 with localized prostate cancer should undergo colorectal cancer screening prior to treatment to evaluate for synchronous rectosigmoid cancer.

Current multidisciplinary management of brain metastases.

Brain metastasis (BM), the most common adult brain tumor, develops in 20% to 40% of patients with late-stage cancer and traditionally are associated with a poor prognosis. The management of patients with BM has become increasingly complex because of new and emerging systemic therapies and advancements in radiation oncology and neurosurgery. Current therapies include stereotactic radiosurgery, whole-brain radiation therapy, surgical resection, laser-interstitial thermal therapy, systemic cytotoxic chemotherapy, targeted agents, and immune-checkpoint inhibitors. Determining the optimal treatment for a specific patient has become increasingly individualized, emphasizing the need for multidisciplinary discussions of patients with BM. Recognizing and addressing the sequelae of BMs and their treatment while maintaining quality of life and neurocognition is especially important because survival for patients with BMs has improved. The authors present current and emerging treatment options for patients with BM and suggest approaches for managing sequelae and disease recurrence.

The effect of MLC leaf width in single-isocenter multi-target radiosurgery with volumetric modulated arc therapy.

PURPOSE: Single-isocenter multi-target (SIMT) volumetric modulated arc therapy (VMAT) is primarily limited to linear accelerators utilizing 2.5 mm leaf width MLCs. We explore feasibility of applying this technique to linear accelerators utilizing MLCs with leaf width of 5 mm. METHODS: Twenty patients with 3-10 intracranial brain metastases originally treated with 2.5 mm MLCs were re-planned using 5 mm MLCs and relevant dosimetric indices were compared. We also evaluated various strategies of adding VMAT arcs to mitigate degradations of dose quality values. RESULTS: Wider MLCs caused small changes in total MUs (5827 ± 2334 vs 5572 ± 2220, p = 0.006), and conformity index (CI) (2.22% ± 0.05%, p = 0.045), but produced more substantial increases in brain V30%[%] and V50%[%] (27.75% ± 0.16% and 20.04% ± 0.13% respectively, p < 0.001 for both), and V12Gy[cc] (16.91% ± 0.12%, p < 0.001). CONCLUSION: SIMT radiosurgery delivered via VMAT using 5 mm wide MLCs can achieve similar CI compared to that using 2.5 mm leaf width MLCs but with moderately increased isodose spill, which can be only partially mitigated by increasing the number of VMAT arcs.

Hypofractionated Image-Guided Radiation Therapy With Simultaneous-Integrated Boost Technique for Limited Metastases: A Multi-Institutional Analysis.

Purpose: To perform a multi-institutional analysis following treatment of limited osseous and/or nodal metastases in patients using a novel hypofractionated image-guided radiotherapy with simultaneous-integrated boost (HIGRT-SIB) technique. Methods: Consecutive patients treated with HIGRT-SIB for ≤5 active metastases at Duke University Medical Center or Durham Veterans' Affairs Medical Center between 2013 and 2018 were analyzed to determine toxicities and recurrence patterns following treatment. Most patients received 50 Gy to the PTVboost and 30 Gy to the PTVelect simultaneously in 10 fractions. High-dose treatment volume recurrence (HDTVR) and low-dose treatment volume recurrence (LDTVR) were defined as recurrences within PTVboost and PTVelect, respectively. Marginal recurrence (MR) was defined as recurrence outside PTVelect, but within the adjacent bone or nodal chain. Distant recurrence (DR) was defined as recurrences not meeting HDTVR, LDTVR, or MR criteria. Freedom from pain recurrence (FFPR) was calculated in patients with painful osseous metastases prior to HIGRT-SIB. Outcome rates were estimated at 12 months using the Kaplan-Meier method. Results: Forty-two patients met inclusion criteria with 59 sites treated with HIGRT-SIB (53% nodal and 47% osseous). Median time from diagnosis to first metastasis was 31 months and the median age at HIGRT-SIB was 69 years. The most common primary tumors were prostate (36%), gastrointestinal (24%), and lung (24%). Median follow-up was 11 months. One acute grade ≥3 toxicity (febrile neutropenia) occurred after docetaxel administration immediately following HIGRT-SIB. Four patients developed late grade ≥3 toxicities: two ipsilateral vocal cord paralyzes and two vertebral compression fractures. The overall pain response rate was 94% and the estimated FFPR at 12 months was 72%. The estimated 12 month rate of HDTVR, LDTVR, MR, and DR was 3.6, 6.2, 7.6, and 55.8%, respectively. DR preceded MR, HDTVR, or LDTVR in each instance. The estimated 12 month probability of in-field and marginal control was 90.0%. Conclusion: Targeting areas at high-risk for occult disease with a lower radiation dose, while simultaneously boosting gross disease with HIGRT in patients with limited osseous and/or nodal metastases, has a high rate of treated metastasis control, a low rate of MR, acceptable toxicity, and high rate of pain palliation. Further investigation with prospective trials is warranted.

Increasing PET Use in Small Cell Lung Cancer: Survival Improvement and Stage Migration in the VA Central Cancer Registry.

Background: Accurate staging for small cell lung cancer (SCLC) is critical for determining appropriate therapy. The clinical impact of increasing PET adoption and stage migration is well described in non-small cell lung cancer but not in SCLC. The objective of this study was to evaluate temporal trends in PET staging and survival in the Veterans Affairs Central Cancer Registry and the impact of PET on outcomes. Patients and Methods: Patients diagnosed with SCLC from 2001 to 2010 were identified. PET staging, overall survival (OS), and lung cancer-specific survival (LCSS) were assessed over time. The impact of PET staging on OS and LCSS was assessed for limited-stage (LS) and extensive-stage (ES) SCLC. Results: From 2001 to 2010, PET use in a total of 10,135 patients with SCLC increased from 1.1% to 39.2%. Median OS improved for all patients (from 6.2 to 7.9 months), those with LS-SCLC (from 10.9 to 13.2 months), and those with ES-SCLC (from 5.0 to 7.0 months). Among staged patients, the proportion of ES-SCLC increased from 63.9% to 65.7%. Among 1,536 patients with LS-SCLC treated with concurrent chemoradiotherapy, 397 were staged by PET. In these patients, PET was associated with longer OS (median, 19.8 vs 14.3 months; hazard ratio [HR], 0.78; 95% CI, 0.68-0.90; P<.0001) and LCSS (median, 22.9 vs 16.7 months; HR, 0.74; 95% CI, 0.63-0.87; P<.0001) with multivariate adjustment and propensity-matching. In the 6,143 patients with ES-SCLC, PET was also associated with improved OS and LCSS. Conclusions: From 2001 to 2010, PET staging increased in this large cohort, with a corresponding relative increase in ES-SCLC. PET was associated with greater OS and LCSS for LS-SCLC and ES-SCLC, likely reflecting stage migration and stage-appropriate therapy. These findings emphasize the importance of PET in SCLC and support its routine use.

Predicting intracranial progression following stereotactic radiosurgery for brain metastases: Implications for post SRS imaging.

PURPOSE: Follow-up imaging after stereotactic radiosurgery (SRS) is crucial to identify salvageable brain metastases (BM) recurrence. As optimal imaging intervals are poorly understood, we sought to build a predictive model for time to intracranial progression. METHODS: Consecutive patients treated with SRS for BM at three institutions from January 1, 2002 to June 30, 2017 were retrospectively reviewed. We developed a model using stepwise regression that identified four prognostic factors and built a predictive nomogram. RESULTS: We identified 755 patients with primarily non-small cell lung, breast, and melanoma BMs. Factors such as number of BMs, histology, history of prior whole-brain radiation, and time interval from initial cancer diagnosis to metastases were prognostic for intracranial progression. Per our nomogram, risk of intracranial progression by 3 months post-SRS in the high-risk group was 21% compared to 11% in the low-risk group; at 6 months, it was 43% versus 27%. CONCLUSION: We present a nomogram estimating time to BM progression following SRS to potentially personalize surveillance imaging.

CIED malfunction in patients receiving radiation is a rare event that could be detected by remote monitoring.

INTRODUCTION: An increasing number of patients with cardiac devices require radiation therapy for treatment of a variety of cancers. This study aimed to identify the incidence and predictors of cardiac implantable electronic devices (CIED) malfunction in a real-world population that has received radiation therapy. METHODS: This retrospective cohort study included 109 adult patients who received radiation therapy at the University of Rochester Medical Center, Radiation Oncology Department, between 2000 and 2015. Sixty patients had pacemakers and 49 had automatic implantable cardioverter defibrillators. Subjects received either high energy (16 MV) and/or low energy (6 MV) photon beams with or without electron beams (6-16 MeV). We included interrogations done from first day of radiation and up to 3 months' postradiation therapy. Outcomes analyzed were device-related malfunctions and device-related clinical events. Fisher's exact, Wilcoxon, and Kruskall-Wallis tests were used for bivariate analysis. Logistic regression with robust adjustment was used for multivariate analysis. RESULTS: We identified six device-related malfunctions. All events were minor and included partial settings reset leading to loss of historical data, pacing thresholds changes, lead impedance changes, and LV output increase. Two patients had device-related clinical events, including dyspnea and diaphragmatic-stimulation. In bivariate analysis, CIED malfunction was associated with CIED duration in situ. In multivariate analysis, there was no significant statistical association between adverse events and beam energy type, CIED location, or dose of radiation delivered to the target. CONCLUSIONS: CIED malfunctions are uncommon in real-world patients and associated with minor clinical events. In our cohort, remote CIED monitoring would have identified all events.

Managing Patients With Oligometastatic Non-Small-Cell Lung Cancer.

Metastatic lung cancer has long been considered incurable, with the goal of treatment being palliation. However, a clinically meaningful number of these patients with limited metastases (approximately 25%) are living long term after definitive treatment to all sites of active disease. These patients with so-called oligometastatic disease likely represent a distinct clinical group who may possess a more indolent biology compared with their more widely metastatic counterparts. Hellman and Weichselbaum proposed the existence of the oligometastatic state, on the basis of the spectrum theory of cancer spread. The literature suggests that an oligometastatic state exists in patients with non-small-cell lung cancer (NSCLC). This observation in the setting of rapidly evolving systemic therapies, including immune checkpoint inhibitors and an increasing number of targeted therapies, represents a unique clinical opportunity. Metastasis-directed therapies to address sites of disease include surgery (metastasectomy) and/or radiation therapy. Available evidence suggests that treating patients with limited or oligometastases may improve outcomes in a meaningful way; however, the majority of the randomized data includes patients with intracranial metastatic disease, and there are limited robust, randomized data available in the setting of NSCLC with only extracranial sites of metastatic disease. Ongoing randomized trials, including NRG-LU002 and the UK Conventional Care Versus Radioablation (Stereotactic Body Radiotherapy) for Extracranial Oligometastases trial, are aimed at evaluating this question further. One of the current limitations of aggressive treatment of oligometastatic NSCLC is the inability to accurately identify these patients before therapy, yet molecular markers, including microRNA profiles, are being investigated as a promising way to identify these patients.

SBRT for Hepatocellular Carcinoma: 8-Year Experience from a Regional Transplant Center.

PURPOSE: The study aimed to evaluate stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC) in patients not eligible for liver transplant (LT). METHODS: We retrospectively identified transplant-ineligible HCC patients treated with SBRT to the liver between 2004 and 2013. Our primary endpoint was overall survival (OS). We also report treatment toxicities using CTCAE 3.0, radiographic response, and patterns of failure. RESULTS: We identified 93 patients with median age at SBRT of 65.8 years. Forty-six percent were classified as Child-Pugh B or C and 85% had an Eastern Cooperative Oncology Group performance status of 1-2. After SBRT, 86% of patients experienced no or mild treatment-related adverse events. Only 8% of patients experienced grade 3 and 2% of patients experienced grade 4 adverse events. Overall radiographic response was complete in 1.2%, partial in 35.4%, stable in 43.9%, and progressive disease in 19.5%. Median OS was 8.8 months with 1-, 2-, and 3-year OS rates of 38.0, 29.8 and 21.2%, respectively. The Cancer of the Liver Italian Program (CLIP) score was found to strongly correlate with survival. Median OS for patients with CLIP scores of 0, 1, 2, and 3 was 21.1, 8.5, 5.1, and 7.1 months, respectively (p = 0.003). CONCLUSION: Our series demonstrates that SBRT is generally safe for HCC patients, even those with advanced liver failure. Although survival is generally poor, we were able to identify a group of patients with good liver function and early tumor stage who can achieve median OS of close to 2 years with SBRT.

Brain radiation injury leads to a dose- and time-dependent recruitment of peripheral myeloid cells that depends on CCR2 signaling.

BACKGROUND: Cranial radiotherapy is used to treat tumors of the central nervous system (CNS), as well as non-neoplastic conditions such as arterio-venous malformations; however, its use is limited by the tolerance of adjacent normal CNS tissue, which can lead to devastating long-term sequelae for patients. Despite decades of research, the underlying mechanisms by which radiation induces CNS tissue injury remain unclear. Neuroinflammation and immune cell infiltration are a recognized component of the CNS radiation response; however, the extent and mechanisms by which bone marrow-derived (BMD) immune cells participate in late radiation injury is unknown. Thus, we set out to better characterize the response and tested the hypothesis that C-C chemokine receptor type 2 (CCR2) signaling was required for myeloid cell recruitment following brain irradiation. METHODS: We used young adult C57BL/6 male bone marrow chimeric mice created with donor mice that constitutively express enhanced green fluorescent protein (eGFP). The head was shielded to avoid brain radiation exposure during chimera construction. Radiation dose and time response studies were conducted in wild-type chimeras, and additional experiments were performed with chimeras created using donor marrow from CCR2 deficient, eGFP-expressing mice. Infiltrating eGFP+ cells were identified and quantified using immunofluorescent microscopy. RESULTS: Brain irradiation resulted in a dose- and time-dependent infiltration of BMD immune cells (predominately myeloid) that began at 1 month and persisted until 6 months following ≥15 Gy brain irradiation. Infiltration was limited to areas that were directly exposed to radiation. CCR2 signaling loss resulted in decreased numbers of infiltrating cells at 6 months that appeared to be restricted to cells also expressing major histocompatibility complex class II molecules. CONCLUSIONS: The potential roles played by infiltrating immune cells are of current importance due to increasing interest in immunotherapeutic approaches for cancer treatment and a growing clinical interest in survivorship and quality of life issues. Our findings demonstrate that injury from brain radiation facilitates a dose- and time-dependent recruitment of BMD cells that persists for at least 6 months and, in the case of myeloid cells, is dependent on CCR2 signaling.

Adult murine hippocampal neurogenesis is inhibited by sustained IL-1ß and not rescued by voluntary running.

Acute neuroinflammation reduces adult hippocampal neurogenesis but the role of chronic neuroinflammation, which may be more representative of ongoing processes in CNS disorders, remains relatively unknown. Interleukin-1ß (IL-1ß) is a pro-inflammatory cytokine that has been shown to acutely impair neurogenesis. To further investigate the relationship between sustained IL-1ß expression and adult neurogenesis, a mouse model with an IL-1ß excisionally activated transgene, IL-1ß(XAT), was utilized. Upon exposure to Cre recombinase, IL-1ß overexpression in this model results in chronic neuroinflammation, which persists up to 12 months and causes glial activation, cellular recruitment, and deficits in learning and memory. We hypothesized that adult neurogenesis would be reduced by sustained hippocampal IL-1ß overexpression and rescued by voluntary running, which has been shown to enhance neurogenesis. Hippocampal inflammation in the IL-1ß(XAT) model severely impaired doublecortin (DCX) positive cells at 1 and 3 months after IL-1ß induction. Furthermore, BrdU labeling demonstrated a shift in cell lineage from neuronal to astroglial in the context of sustained hippocampal IL-1ß overexpression. Deletion of the IL-1 receptor prevented the decrease in DCX(+) cells. Voluntary running did not attenuate the effects of IL-1ß expression demonstrated by DCX staining. These results suggest that chronic neuroinflammation severely impairs adult hippocampal neurogenesis and voluntary running is not beneficial as a therapy to rescue these effects.