Is Postoperative Radiotherapy Needed in the Management of Adult Craniopharyngiomas?

BACKGROUND: The optimal treatment of adult craniopharyngioma (CP) remains controversial. Although benign, these tumors tend to recur locally. The choice between gross total resection (GTR) versus subtotal resection (STR) with adjuvant or delayed radiotherapy (RT) is debated. The objective of this study is to review our experience with adult CPs over a 20-year period and identify an optimal management strategy. METHODS: From 1999 to 2020, we reviewed all patients diagnosed with CP at our institution. We collected data regarding tumor characteristics, treatments, and toxicity. Disease progression was defined as growth on imaging. Descriptive statistics were used to assess patient characteristics. The Kaplan Meier method was used to assess progression-free survival (PFS) and corresponding 95% confidence intervals (CI) from the time since treatment initiation. RESULTS: Twenty-four patients with a median age of 50 were included in this study. The median follow-up was 85 months. Seven patients had initial GTR, 10 STR, and 7 STR + RT. The overall 5-year PFS was 56% (95% CI: 38-83%): 100% in the STR + RT group, 69% in the GTR group, and 18% in the STR group (p = 0.01). Of the 17 patients initially treated with surgery alone, 3 with GTR and 6 with STR required salvage RT at a median of 46 months, with no further progression after salvage RT. CONCLUSIONS: Our study underscores the importance of RT for local control and suggests that STR + RT should be considered a viable option in the management of these tumors as it may be associated with improved PFS compared to surgery alone.

Pharmacological and molecular characterization of the A-type muscarinic acetylcholine receptor from Anopheles gambiae.

Muscarinic acetylcholine receptors (mAChRs) which are G protein-coupled receptors play key roles in insect physiology. Whereas vertebrate mAChRs are important targets for pharmaceutical drugs, insect mAChRs are under-exploited by the agro-chemical industry. Moreover, insect mAChRs have been less well studied than their vertebrate counterparts. Their critical functions mean that a better knowledge of the insect mAChRs is crucial for the effort to develop a new molecular-level strategy for insect pest management. Almost all insects possess three mAChRs named A, B and C which differ according to their coupling effector systems and their pharmacological profile. The aim of this study was to characterize the A-type mAChR (mAChR-A) from Anopheles gambiae which is the major vector of malaria in order to develop new strategies in pest management. In this paper, we reported that mAChR-A is more expressed in adult mosquitoes than in larvae. Furthermore, using calcium imaging recordings, we found that the An. gambiae mAChR-A expressed in Sf9 cells is activated by specific muscarinic agonists acetylcholine, muscarine and oxotremorine M and blocked by several mAChR antagonists. Moreover, using inhibitors of phosphoinositide pathway such as Gαq/11 protein blocker, we have shown that an increased intracellular calcium concentration elicited by the acetylcholine application was mediated by PLC/IP3R pathway. As a rise in intracellular calcium concentration could lead to an increase in the insecticide target sensitivity, these results suggest that An. gambiae mAChR-A should not be only considered as a potential target for new molecules but also as a key element to optimize the efficacy of insecticide in vector control.

Exposure to a sublethal dose of imidacloprid induces cellular and physiological changes in Periplaneta americana: Involvement of α2 nicotinic acetylcholine subunit in imidacloprid sensitivity.

Neonicotinoids are the most important class of insecticides used as pest management tools during several decades. Exposition of insect to sublethal dose of insecticide induces physiological and cellular changes that could contribute to the adaptation of the insects in order to loss their sensitivity to insecticides. The aim of our study is to demonstrate that a subchronic exposure to a sublethal dose of a neonicotinoid imidacloprid is sufficient to induce molecular changes leading to a loss of imidacloprid sensitivity. We report that in the cockroach, Periplaneta americana, subchronic exposure to a sublethal dose of imidacloprid induced weak changes in detoxification enzyme activity and a significant decrease of the nicotinic acetylcholine α2 mRNA. This molecular effect is correlated to a decrease of imidacloprid sensitivity of cockroaches. Using RNA interference, we shown the key role of nicotinic acetylcholine α2 subunit in imidacloprid sensitivity. Thus, quantitative changes in insecticide targets lead to decreased sensitivity to insecticides. This parameter needs to be considered in order to develop sustainable insect resistance management strategies.

Independently validated sex-specific nomograms for predicting survival in patients with newly diagnosed glioblastoma: NRG Oncology RTOG 0525 and 0825.

BACKGROUND/PURPOSE: Glioblastoma (GBM) is the most common primary malignant brain tumor. Sex has been shown to be an important prognostic factor for GBM. The purpose of this study was to develop and independently validate sex-specific nomograms for estimation of individualized GBM survival probabilities using data from 2 independent NRG Oncology clinical trials. METHODS: This analysis included information on 752 (NRG/RTOG 0525) and 599 (NRG/RTOG 0825) patients with newly diagnosed GBM. The Cox proportional hazard models by sex were developed using NRG/RTOG 0525 and significant variables were identified using a backward selection procedure. The final selected models by sex were then independently validated using NRG/RTOG 0825. RESULTS: Final nomograms were built by sex. Age at diagnosis, KPS, MGMT promoter methylation and location of tumor were common significant predictors of survival for both sexes. For both sexes, tumors in the frontal lobes had significantly better survival than tumors of multiple sites. Extent of resection, and use of corticosteroids were significant predictors of survival for males. CONCLUSIONS: A sex specific nomogram that assesses individualized survival probabilities (6-, 12- and 24-months) for patients with GBM could be more useful than estimation of overall survival as there are factors that differ between males and females. A user friendly online application can be found here- https://npatilshinyappcalculator.shinyapps.io/SexDifferencesInGBM/ .

Oxaloacetate Protects Rat Liver From Experimental Warm Ischemia/Reperfusion Injury by Improving Cellular Energy Metabolism.

Liver ischemia/reperfusion injury (IRI) is an important cause of liver damage especially early after liver transplantation, following liver resection, and in other clinical situations. Using rat experimental models, we identified oxaloacetate (OAA) as a key metabolite able to protect hepatocytes from hypoxia and IRI. In vitro screening of metabolic intermediates beneficial for hepatocyte survival under hypoxia was performed by measures of cell death and injury. In vivo, the effect of OAA was evaluated using the left portal vein ligation (LPVL) model of liver ischemia and a model of warm IRI. Liver injury was evaluated in vivo by serum transaminase levels, liver histology, and liver weight (edema). Levels and activity of caspase 3 were also measured. In vitro, the addition of OAA to hepatocytes kept in a hypoxic environment significantly improved cell viability (P < 0.01), decreased cell injury (P < 0.01), and improved energy metabolism (P < 0.01). Administration of OAA significantly reduced the extent of liver injury in the LPVL model with lower levels of alanine aminotransferase (ALT; P < 0.01), aspartate aminotransferase (AST; P < 0.01), and reduced liver necrosis (P < 0.05). When tested in a warm IRI model, OAA significantly decreased ALT (P < 0.001) and AST levels (P < 0.001), prevented liver edema (P < 0.001), significantly decreased caspase 3 expression (P < 0.01), as well as histological signs of cellular vesiculation and vacuolation (P < 0.05). This was associated with higher adenosine triphosphate (P < 0.05) and energy charge levels (P < 0.01). In conclusion, OAA can significantly improve survival of ischemic hepatocytes. The hepatoprotective effect of OAA was associated with increased levels of liver bioenergetics both in vitro and in vivo. These results suggest that it is possible to support mitochondrial activity despite the presence of ischemia and that OAA can effectively reduce ischemia-induced injury in the liver.

Assessment of function and quality of life in a phase II multi-institutional clinical trial of fractionated simultaneous in-field boost radiotherapy for patients with 1-3 metastases.

We examined functional outcomes and quality of life of whole brain radiotherapy (WBRT) with integrated fractionated stereotactic radiotherapy boost (FSRT) for brain metastases treatment. Eighty seven people with 1-3 brain metastases (54/87 lung primary, 42/87 single brain metastases) were enrolled on this Phase II trial of WBRT (30 Gy/10) + simultaneous FSRT, (60 Gy/10). Median overall follow-up and survival was 5.4 months, 6 month actuarial intra-lesional control was 78 %; only 1 patient exhibited grade 4 toxicity (worsened seizures); most treatment related toxicity was grade 1 or 2; 2/87 patients demonstrated asymptomatic radiation necrosis on follow-up imaging. Mean (Min-Max) baseline KPS, Mini Mental Status Exam (MMSE) and FACT-BR quality of life were 83 (70-100), 28 (21-30) and 143 (98-153). Lower baseline MMSE (but not KPS or FACT-Br) was associated with worse survival after adjusting for age, number of metastases, primary and extra-cranial disease status. Crude rates of deterioration (>10 points decrease from baseline for KPS and FACT-Br, MMSE fall to <27) ranged from 26 to 38 % for KPS, 32-59 % for FACT-Br and 0-16 % for MMSE depending on the time-point assessed with higher rates generally noted at earlier time points (≤6 months post-treatment). Using a linear mixed models analysis, significant declines from baseline were noted for KPS and FACT-Br (largest effects at 6 weeks to 3 months) with no significant change in MMSE. The effects on function and quality of life of this integrated treatment of WBRT + simultaneous FSRT were similar to other published series combining WBRT + radiosurgery.

Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-ß (IFNB1) promoter following Sendai virus (SeV) infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of ß-catenin (CTNNB1) upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3) inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

The nitrate transporter MtNPF6.8 (MtNRT1.3) transports abscisic acid and mediates nitrate regulation of primary root growth in Medicago truncatula.

Elongation of the primary root during postgermination of Medicago truncatula seedlings is a multigenic trait that is responsive to exogenous nitrate. A quantitative genetic approach suggested the involvement of the nitrate transporter MtNPF6.8 (for Medicago truncatula NITRATE TRANSPORTER1/PEPTIDE TRANSPORTER Family6.8) in the inhibition of primary root elongation by high exogenous nitrate. In this study, the inhibitory effect of nitrate on primary root elongation, via inhibition of elongation of root cortical cells, was abolished in npf6.8 knockdown lines. Accordingly, we propose that MtNPF6.8 mediates nitrate inhibitory effects on primary root growth in M. truncatula. pMtNPF6.8:GUS promoter-reporter gene fusion in Agrobacterium rhizogenes-generated transgenic roots showed the expression of MtNPF6.8 in the pericycle region of primary roots and lateral roots, and in lateral root primordia and tips. MtNPF6.8 expression was insensitive to auxin and was stimulated by abscisic acid (ABA), which restored the inhibitory effect of nitrate in npf6.8 knockdown lines. It is then proposed that ABA acts downstream of MtNPF6.8 in this nitrate signaling pathway. Furthermore, MtNPF6.8 was shown to transport ABA in Xenopus spp. oocytes, suggesting an additional role of MtNPF6.8 in ABA root-to-shoot translocation. (15)NO3(-)-influx experiments showed that only the inducible component of the low-affinity transport system was affected in npf6.8 knockdown lines. This indicates that MtNPF6.8 is a major contributor to the inducible component of the low-affinity transport system. The short-term induction by nitrate of the expression of Nitrate Reductase1 (NR1) and NR2 (genes that encode two nitrate reductase isoforms) was greatly reduced in the npf6.8 knockdown lines, supporting a role of MtNPF6.8 in the primary nitrate response in M. truncatula.

Use of double-stranded RNA targeting ß2 divergent nicotinic acetylcholine receptor subunit to control pea aphid Acyrthosiphon pisum at larval and adult stages.

BACKGROUND: In recent years, the use of the RNA interference technology (RNAi) has emerged as one of the new strategies for species-specific control of insect pests. Its specificity depends on the distinctiveness of the target gene sequence for a given species. In this work, we assessed in the pea aphid Acyrthosiphon pisum (A. pisum) the use of a double-stranded RNA (dsRNA) that targets the ß2 divergent nicotinic acetylcholine receptor (nAChR) subunit (dsRNA-ß2), which shares low sequence identity with other subunits, to control populations of this pest at different developmental stages. Because nAChRs are targeted by neonicotinoid insecticides such as imidacloprid, we also assessed the effect of dsRNA-ß2 coupled to this insecticide on aphid survival. Finally, because the effect of a control agent on beneficial insect must be considered before any use of new pest management strategies, the acute toxicity of dsRNA-ß2 combined with imidacloprid was evaluated on honeybee Apis mellifera. RESULTS: In this work, we demonstrated that dsRNA-ß2 alone has an insecticidal effect on aphid larvae and adults. Moreover, dsRNA-ß2 and imidacloprid effects on aphid larvae and adults were additive, meaning that dsRNA-ß2 did not alter the efficacy of imidacloprid on these two developmental stages. Also, no obvious acute toxicity on Apis mellifera was reported. CONCLUSION: Using RNAi that targets ß2 divergent nAChR subunit is effective alone or combined with imidacloprid to control A. pisum at larval and adult stages. Because no obvious Apis mellifera mortality has been reported, this RNAi-based pest management strategy should be considered to control insect pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Using RNA interference targeting a nicotinic acetylcholine receptor subunit to counteract insecticide accommodation mechanisms: example of the ß1 subunit in the imidacloprid-accommodated American cockroach, Periplaneta americana.

Insecticide accommodation and resistance are limiting factors to the much-needed increase in agricultural production. Various physiological and cellular modifications, such as the changes of insecticide molecular targets, have been linked to these events. Thus, a previous study demonstrated that the imidacloprid accommodation set up by the cockroach Periplaneta americana after an exposure to a sublethal dose of this insecticide involves functional alterations of two nicotinic acetylcholine receptor (nAChR) subtypes. As RNA interference (RNAi) is one of the most promising strategies for controlling pest insects, we evaluated, in this study, the use of RNAi that targets the ß1 nAChR subunit to counteract the imidacloprid accommodation phenomenon in cockroaches. Interestingly, we showed that ingestion of dsRNA-ß1 increased the sensitivity to imidacloprid of accommodated cockroaches. Thus, we have demonstrated for the first time that RNAi that targets an nAChR subunit can counteract the accommodation mechanism to insecticide targeting nAChRs set up by an insect.

Impact of the delay in cryopreservation timing during biobanking procedures on human liver tissue metabolomics.

The liver is a highly specialized organ involved in regulating systemic metabolism. Understanding metabolic reprogramming of liver disease is key in discovering clinical biomarkers, which relies on robust tissue biobanks. However, sample collection and storage procedures pose a threat to obtaining reliable results, as metabolic alterations may occur during sample handling. This study aimed to elucidate the impact of pre-analytical delay during liver resection surgery on liver tissue metabolomics. Patients were enrolled for liver resection during which normal tissue was collected and snap-frozen at three timepoints: before transection, after transection, and after analysis in Pathology. Metabolomics analyses were performed using 1H Nuclear Magnetic Resonance (NMR) and Liquid Chromatography-Mass Spectrometry (LC-MS). Time at cryopreservation was the principal variable contributing to differences between liver specimen metabolomes, which superseded even interindividual variability. NMR revealed global changes in the abundance of an array of metabolites, namely a decrease in most metabolites and an increase in ß-glucose and lactate. LC-MS revealed that succinate, alanine, glutamine, arginine, leucine, glycerol-3-phosphate, lactate, AMP, glutathione, and NADP were enhanced during cryopreservation delay (all p<0.05), whereas aspartate, iso(citrate), ADP, and ATP, decreased (all p<0.05). Cryopreservation delays occurring during liver tissue biobanking significantly alter an array of metabolites. Indeed, such alterations compromise the integrity of metabolomic data from liver specimens, underlining the importance of standardized protocols for tissue biobanking in hepatology.

Characterization of the first honeybee Ca²âº channel subunit reveals two novel species- and splicing-specific modes of regulation of channel inactivation.

The honeybee is a model system to study learning and memory, and Ca(2+) signals play a key role in these processes. We have cloned, expressed, and characterized the first honeybee Ca(2+) channel subunit. We identified two splice variants of the Apis CaVß Ca(2+) channel subunit (Am-CaVß) and demonstrated expression in muscle and neurons. Although AmCaVß shares with vertebrate CaVß subunits the SH3 and GK domains, it beholds a unique N terminus that is alternatively spliced in the first exon to produce a long (a) and short (b) variant. When expressed with the CaV2 channels both, AmCaVßa and AmCaVßb, increase current amplitude, shift the voltage-sensitivity of the channel, and slow channel inactivation as the vertebrate CaVß2a subunit does. However, as opposed to CaVß2a, slow inactivation induced by Am-CaVßa was insensitive to palmitoylation but displayed a unique PI3K sensitivity. Inactivation produced by the b variant was PI3K-insensitive but staurosporine/H89-sensitive. Deletion of the first exon suppressed the sensitivity to PI3K inhibitors, staurosporine, or H89. Recording of Ba(2+) currents in Apis neurons or muscle cells evidenced a sensitivity to PI3K inhibitors and H89, suggesting that both AmCaVß variants may be important to couple cell signaling to Ca(2+) entry in vivo. Functional interactions with phospho-inositide and identification of phosphorylation sites in AmCaVßa and AmCaVßb N termini, respectively, suggest that AmCaVß splicing promoted two novel and alternative modes of regulation of channel activity with specific signaling pathways. This is the first description of a splicing-dependent kinase switch in the regulation of Ca(2+) channel activity by CaVß subunit.

Liver fibrosis protects mice from acute hepatocellular injury.

BACKGROUND & AIMS: Development of fibrosis is part of the pathophysiologic process of chronic liver disease. Although it is considered deleterious, it also represents a form of tissue repair. Deposition of extracellular matrix changes the cellular environment of the liver; we investigated whether it increases resistance to noxious stimuli and the role of changes in intracellular signaling to hepatocytes in mediating this effect. METHODS: Primary cultures of mouse hepatocytes were exposed to type I collagen (COL1); cell injury was assessed by morphologic and biochemical criteria. The expression of Bcl-2 family members was evaluated by immunoblot analyses. Activation of extracellular signal-regulated kinase (ERK) was assessed using phospho-specific antibodies. Liver fibrosis was induced by repeated administration of thioacetamide or carbon tetrachloride to mice; mice were then exposed to Fas antibodies. RESULTS: Hepatocytes exposed to COL1 were more resistant to a variety of hepatotoxins, in a dose-dependent manner, and had lower levels of Bad, Bid, and Bax proapoptotic proteins compared with control hepatocytes. Activation of ERK1/2 was stronger and quicker in hepatocytes exposed to COL1. The MEK1/2 inhibitors U0126 and PD98059 reversed the protective effects of COL1 and the decrease in proapoptotic proteins. Hepatocytes isolated from ERK1(-/-) mice were insensitive to the protective effect of COL1. Fibrotic livers from wild-type mice had high levels of phospho-ERK1 and were resistant to Fas-induced cell death. ERK1(-/-) mice lost this effect. CONCLUSIONS: Production of COL1 during liver fibrosis induces a hepatoprotective response that is mediated by activation of ERK1 signaling.

Failure pattern following complete resection plus radiotherapy and temozolomide is at the resection margin in patients with glioblastoma.

Glioblastomas (GBM) are highly motile cancers that invade through normal brain. In the absence of curative chemotherapy this invasion, beyond surgical and radiotherapy margins, to distant brain sites is thought to be an important cause of treatment failure. Paradoxically, studies analyzing failure patterns have consistently shown that the large majority of failures occur at the original tumor site. This conflict may be explained by the fact these cancers are often only sub-totally resected and radiotherapy and chemotherapies fail to control this significant local cancer burden. We analyzed the failure pattern in 20 consecutive patients with complete resection of the gadolinium-enhancing portion of GBM demonstrated on the immediate post-operative magnetic resonance study, and who underwent a radical course of radiotherapy and chemotherapy. We found that recurrences occurred only at the resection margin in 17 of 20 patients. Recurrences were exclusively distant in 2 of 20 patients and occurred at both the resection margin and a distant site in 1 of 20 cases. We found that even in cases of complete resection of the gadolinium-enhancing portion of GBM 85 % of recurrences are localized to the resection margin.

Metabolomics-Guided Identification of a Distinctive Hepatocellular Carcinoma Signature.

BACKGROUND: Hepatocellular carcinoma (HCC) is a major contributor to cancer-related morbidity and mortality burdens globally. Given the fundamental metabolic activity of hepatocytes within the liver, hepatocarcinogenesis is bound to be characterized by alterations in metabolite profiles as a manifestation of metabolic reprogramming. METHODS: HCC and adjacent non-tumoral liver specimens were obtained from patients after HCC resection. Global patterns in tissue metabolites were identified using non-targeted 1H Nuclear Magnetic Resonance (1H-NMR) spectroscopy whereas specific metabolites were quantified using targeted liquid chromatography-mass spectrometry (LC/MS). RESULTS: Principal component analysis (PCA) within our 1H-NMR dataset identified a principal component (PC) one of 53.3%, along which the two sample groups were distinctively clustered. Univariate analysis of tissue specimens identified more than 150 metabolites significantly altered in HCC compared to non-tumoral liver. For LC/MS, PCA identified a PC1 of 45.2%, along which samples from HCC tissues and non-tumoral tissues were clearly separated. Supervised analysis (PLS-DA) identified decreases in tissue glutathione, succinate, glycerol-3-phosphate, alanine, malate, and AMP as the most important contributors to the metabolomic signature of HCC by LC/MS. CONCLUSIONS: Together, 1H-NMR and LC/MS metabolomics have the capacity to distinguish HCC from non-tumoral liver. The characterization of such distinct profiles of metabolite abundances underscores the major metabolic alterations that result from hepatocarcinogenesis.

Radiation-Induced Sarcomas of the Breast: A Review of a 20-Year Single-Center Experience.

Background Radiation-induced sarcomas (RISs) are histologically proven sarcomas within or around a previously irradiated site, per Cahan's criteria. RIS incidence is higher in breast cancer compared to other solid cancers and the prognosis remains poor given limited treatment options. This study aimed to review 20-year experience with RISs at a large tertiary care center. Methodology Using our institutional cancer registry database, we included patients meeting Cahan's criteria diagnosed between 2000 and 2020. Patient demographics, oncologic treatment, and oncologic outcomes data were collected. Descriptive statistics were used to describe demographic data. Oncologic outcomes were assessed using the Kaplan-Meier method. Results A total of 19 patients were identified. The median age at RIS diagnosis was 72 years (range = 39-82 months), and the median latency period for the development of RIS was 112 months (range = 53-300 months). All patients underwent surgery, three patients received systemic therapy, and six patients received re-irradiation as salvage treatment. The median follow-up time was 31 months (range = 6-172 months) from the diagnosis of RIS. Overall, five patients had local recurrence, and one patient developed distant metastases. The median time to progression was seven months (range = 4-14 months). The progression-free survival (95% confidence interval (CI)) at two years was 56.1% (37.4-84.4%). At follow-up two years after the diagnosis of sarcoma, the overall survival (95% CI) was 88.9% (75.5-100%). Conclusions While breast RIS remains rare, when managed in a large tertiary care center, overall survival outcomes appear favorable. A significant proportion of patients recur locally after maximal treatment and require salvage therapy to improve outcomes. These patients should be managed in high-volume centers where multidisciplinary expertise is available.

Management of Oligometastatic Breast Cancer: An Expert Committee's Opinion.

Patients with oligometastatic breast cancer (BC) are candidates of choice for metastasis-directed therapy (MDT). This paper summarizes the opinions of an expert committee about the management of oligometastatic BC. The experts could complete the questionnaire from 13 September 2021, to 10 October 2021, followed by a discussion. The experts were physicians working in the Province of Quebec (Canada) and specialized in BC care, including surgical oncologists, medical oncologists, and radiation oncologists. The experts provided their opinions about the context of the disease and therapeutic approach, local and systemic therapies, and the prognosis of oligometastatic BC. In addition to the expert panel's opinions about the management of oligometastatic disease per se, the experts stated that a prospective data registry should be implemented to collect data about oligometastatic BC to improve knowledge about oligometastatic BC and implement data-driven MDT. These data could also allow for the design of treatment algorithms. In conclusion, this paper presents the expert panel's opinions about the management of oligometastatic BC and highlights the needs to be met to improve the care of this condition.

Evaluation of Dosimetry Formalisms in Intraoperative Radiation Therapy of Glioblastoma.

PURPOSE: The intraoperative radiotherapy in newly diagnosed glioblastoma multiforme (INTRAGO) clinical trial assesses survival in patients with glioblastoma treated with intraoperative radiation therapy (IORT) using the INTRABEAM. Treatment planning for INTRABEAM relies on vendor-provided in-water depth dose curves obtained according to the TARGeted Intraoperative radioTherapy (TARGIT) dosimetry protocol. However, recent studies have shown discrepancies between the estimated TARGIT and delivered doses. This work evaluates the effect of the choice of dosimetry formalism on organs at risk (OAR) doses. METHODS AND MATERIALS: A treatment planning framework for INTRABEAM was developed to retrospectively calculate the IORT dose in 8 INTRAGO patients. These patients received an IORT prescription dose of 20 to 30 Gy in addition to external beam radiation therapy. The IORT dose was obtained using (1) the TARGIT method; (2) the manufacturer's V4.0 method; (3) the CQ method, which uses an ionization chamber Monte Carlo (MC) calculated factor; (4) MC dose-to-water; and (5) MC dose-to-tissue. The IORT dose was converted to 2 Gy fractions equivalent dose. RESULTS: According to the TARGIT method, the OAR dose constraints were respected in all cases. However, the other formalisms estimated a higher mean dose to OARs and revealed 1 case where the constraint for the brain stem was exceeded. The addition of the external beam radiation therapy and TARGIT IORT doses resulted in 10 cases of OARs exceeding the dose constraints. The more accurate MC calculation of dose-to-tissue led to the highest dosimetric differences, with 3, 3, 2, and 2 cases (out of 8) exceeding the dose constraint to the brain stem, optic chiasm, optic nerves, and lenses, respectively. Moreover, the mean cumulative dose to brain stem exceeded its constraint of 66 Gy with the MC dose-to-tissue method, which was not evident with the current INTRAGO clinical practice. CONCLUSIONS: The current clinical approach of calculating the IORT dose with the TARGIT method may considerably underestimate doses to nearby OARs. In practice, OAR dose constraints may have been exceeded, as revealed by more accurate methods.

Targeted Intraoperative Radiation Therapy during Breast-Conserving Surgery for Patients with Early Stage Breast Cancer: A Phase II Single Center Prospective Trial.

Purpose: Patients with early stage breast cancer (ESBC) are conventionally treated with breast-conserving surgery (BCS) followed by whole-breast external beam radiation therapy (EBRT). The emergence of targeted intraoperative radiation therapy (TARGIT) with Intrabeam has been used as a therapeutic alternative for patients with risk-adapted ESBC. Here we present our radiation therapy toxicities (RTT), postoperative complications (PC), and short-term outcomes of the prospective phase II trial at the McGill University Health Center. Methods and Materials: Patients aged ≥50 years with biopsy-proven hormone receptor-positive, grade 1 or 2, invasive ductal carcinoma of the breast, cT1N0, were eligible for the study. Enrolled patients underwent BCS followed by immediate TARGIT of 20 Gy in 1 fraction. Upon final pathology, patients with low-risk breast cancer (LRBC) received no further EBRT, and those with high-risk breast cancer (HRBC) received further 15 to 16 fractions of whole breast EBRT. HRBC criteria included pathologic tumor size >2 cm, grade 3, positive lympho-vascular invasion, multifocal disease, close margins (<2 mm), or positive nodal disease. Results: A total of 61 patients with ESBC were enrolled in the study; upon final pathology, 40 (65.6%) had LRBC, and 21 (34.4%) had HRBC. The median follow-up was 3.9 years. The most common HRBC criteria were close margins in 66.6% (n = 14) and lymphovascular invasion in 28.6% (n = 6). No grade 4 RTT were observed in either group. The most common PC were seroma and cellulitis for both groups. The rate of locoregional recurrence was 0% in both groups. The overall survival in LRBC was 97.5% and in HRBC 95.2% with no significant differences. Deaths were nonbreast cancer related. Conclusions: In patients with ESBC undergoing BCS, the use of TARGIT shows low rates of RTT and PC complications. Moreover, our short-term outcomes show no significant difference at 3.9 years median follow-up for locoregional recurrence or overall survival between groups of patients receiving TARGIT alone or TARGIT followed by EBRT. Of all patients, 34.4% required further EBRT, most commonly due to close margins.

Phase II multicenter trial combining nivolumab and radiosurgery for NSCLC and RCC brain metastases.

Background: Anti-PD-1 has activity in brain metastases (BM). This phase II open labeled non-randomized single arm trial examined the safety and efficacy of combining nivolumab with radiosurgery (SRS) in the treatment of patients with BM from non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC). Methods: This was a multicenter trial (NCT02978404) in which patients diagnosed with NSCLC or RCC, having ≤ 10 cc of un-irradiated BM and no prior immunotherapy were eligible. Nivolumab (240 mg or 480 mg IV) was administered for up to 2 years until progression. SRS (15-21 Gy) to all un-irradiated BM was delivered within 14 days after the first dose of nivolumab. The primary endpoint was intracranial progression free survival (iPFS). Results: Twenty-six patients (22 NSCLC and 4 RCC) were enrolled between August 2017 and January 2020. A median of 3 (1-9) BM were treated with SRS. Median follow-up was 16.0 months (0.43-25.9 months). Two patients developed nivolumab and SRS related grade 3 fatigue. One-year iPFS and OS were 45.2% (95% CI 29.3-69.6%) and 61.3% (95% CI 45.1-83.3%), respectively. Overall response (partial or complete) of SRS treated BM was attained in 14 out of the 20 patients with ≥1 evaluable follow-up MRI. Mean FACT-Br total scores were 90.2 at baseline and improved to 146.2 within 2-4 months (P = .0007). Conclusions: The adverse event profile and FACT-Br assessments suggested that SRS during nivolumab was well tolerated. Upfront SRS with the initiation of anti-PD-1 prolonged the 1-year iPFS and achieved high intracranial control. This combined approach merits validation randomized studies.