Adjuvant chemotherapy omission after pancreatic cancer resection: a French nationwide study

BACKGROUND

Adjuvant chemotherapy (AC) improves the prognosis after pancreatic ductal adenocarcinoma (PDAC) resection. However, previous studies have shown that a large proportion of patients do not receive or complete AC. This national study examined the risk factors for the omission or interruption of AC.

METHODS

Data of all patients who underwent pancreatic surgery for PDAC in France between January 2012 and December 2017 were extracted from the French National Administrative Database. We considered "omission of adjuvant chemotherapy" (OAC) all patients who failed to receive any course of gemcitabine within 12 postoperative weeks and "interruption of AC" (IAC) was defined as less than 18 courses of AC.

RESULTS

A total of 11 599 patients were included in this study. Pancreaticoduodenectomy was the most common procedure (76.3%), and 31% of the patients experienced major postoperative complications. OACs and IACs affected 42% and 68% of the patients, respectively. Ultimately, only 18.6% of the cohort completed AC. Patients who underwent surgery in a high-volume centers were less affected by postoperative complications, with no impact on the likelihood of receiving AC. Multivariate analysis showed that age ≥ 80 years, Charlson comorbidity index (CCI) ≥ 4, and major complications were associated with OAC (OR = 2.19; CI95%[1.79-2.68]; OR = 1.75; CI95%[1.41-2.18] and OR = 2.37; CI95%[2.15-2.62] respectively). Moreover, age ≥ 80 years and CCI 2-3 or ≥ 4 were also independent risk factors for IAC (OR = 1.54, CI95%[1.1-2.15]; OR = 1.43, CI95%[1.21-1.68]; OR = 1.47, CI95%[1.02-2.12], respectively).

CONCLUSION

Sequence surgery followed by chemotherapy is associated with a high dropout rate, especially in octogenarian and comorbid patients.

Studying the stability of polymer nanoparticles by size exclusion chromatography of radioactive polymers

The properties of nanomedicines will influence how they can deliver drugs to patients reproducibly and effectively. For conventional pharmaceutical products, Chemistry, Manufacturing and Control (CMC) documents require monitoring stability and storage conditions. For nanomedicines, studying these important considerations is hindered by a lack of appropriate methods. In this paper, we show how combining radiolabelling with size exclusion chromatography, using a method called SERP (for Size Exclusion of Radioactive Polymers), can inform on the in vitro degradation of polymer nanoparticles. Using nanoparticles composed of biodegradable poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), we show that SERP is more sensitive than dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) to detect degradation. We also demonstrate that the properties of the polymer composition and the nature of the aqueous buffer affect nanoparticle degradation. Importantly, we show that minute changes in stability that cannot be detected by DLS and NTA impact the pharmacokinetic of nanoparticles injected in vivo. We believe that SERP might prove a valuable method to document and understand the pharmaceutical quality of polymer nanoparticles.

Optimization of a lipid nanoparticle-based protocol for RNA transfection into primary mononuclear phagocytes

The effective delivery of synthetic RNA into mononuclear phagocytes is a prerequisite for experimental research and therapeutic development. However, traditional methods are highly ineffective and toxic for these cells. Here, we aimed to optimize a transfection protocol for primary bone marrow-derived phagocytes, specifically dendritic cells and macrophages, using lipid nanoparticles generated by microfluidics. Our results show that a lipid mixture similar to that used in Moderna's COVID-19 mRNA vaccine outperforms the others tested. Improved mRNA transfection can be achieved by replacing uridine with methylpseudouridine but not methoxyuridine, which interferes with transfection. The addition of diphenyleneiodonium or apocynin can enhance transfection in a cell type-dependent manner without adverse effects, while apolipoprotein E provides no added value. These optimized transfection conditions can also be used for microRNA agonists and antagonists. In sum, this study offers a straightforward, highly efficient, reproducible, and non-toxic protocol to deliver RNA into different primary mononuclear phagocytes in culture.

Conventional cytotoxic chemotherapy for gastrointestinal cancer in patients with cirrhosis: A multicentre case-control study

BACKGROUND & AIMS

Progresses in management make a higher proportion of cirrhotic patients with gastrointestinal (GI) cancer candidates to chemotherapy. Data are needed on the safety and liver-related events associated with the use of chemotherapy in these patients.

METHODS

Forty-nine patients with cirrhosis receiving chemotherapy against GI cancer from 2013 to 2018 were identified in the French Health Insurance Database using ICD-10 codes K70-K74, and matched 1:2 to non-cirrhotic controls (n = 98) on age, tumour type and type of treatment. Adverse events (AE), dose tapering, discontinuation rate, liver-related events and survival rate were compared.

RESULTS

Patients with cirrhosis (Child-Pugh A 91%) more often received lower doses (38.8% vs 7.1%, p < .001), without significant differences in terms of grade 3/4 AE or dose tapering rates (29.6% vs. 36.7%; 22.3% vs 24.4%, respectively). Treatment discontinuation rate was higher in patients with cirrhosis (23.3% vs. 11.3%, p = .005). Child-Pugh (p = .007) and MELD (p = .025) scores increased under chemotherapy. Five patients with cirrhosis (10.2%) had liver decompensation within 12 months, and 17.2% of deaths in the cirrhosis group were liver-related versus 0% in matched controls. WHO-PS stage > 1 (HR 3.74, CI95%: 2.13-6.57, p < .001), TNM-stage M1 (HR 3.61, CI 95%: 1.82-7.16, p < .001), non-colorectal cancer (HR 1.73, CI 95%: 1.05-2.86, p = .032) and bilirubin higher than 5 mg/dL (HR 2.26, CI 95%: 1.39-3.70, p < .001) were independent prognostic factors of 2-year mortality, whereas cirrhosis was not.

CONCLUSIONS

Chemotherapy should be proposed only in patients with compensated cirrhosis with close monitoring of liver function. Dose management remains challenging. Multidisciplinary management is warranted to improve these patients' outcomes.

Encapsulation of conjugated linoleic acid and ruminant trans fatty acids to study the prevention of metabolic syndrome-a review

Studies have reported the potential benefits of consuming conjugated linoleic acid (CLA) and ruminant trans fatty acids (R-TFAs) in reducing the risk factors of metabolic syndrome (MetS). In addition, encapsulation of CLA and R-TFAs may improve their oral delivery and further decrease the risk factors of MetS. The objectives of this review were (1) to discuss the advantages of encapsulation; (2) to compare the materials and techniques used for encapsulating CLA and R-TFAs; and (3) to review the effects of encapsulated vs non-encapsulated CLA and R-TFAs on MetS risk factors. Examination of papers citing micro- and nano-encapsulation methods used in food sciences, as well as the effects of encapsulated vs non-encapsulated CLA and R-TFAs, was conducted using the PubMed database. A total of 84 papers were examined; of these, 18 studies were selected that contained information on the effects of encapsulated CLA and R-TFAs. The 18 studies that described encapsulation of CLA or R-TFAs indicated that micro- or nano-encapsulation processes stabilized CLA and prevented oxidation. CLA was mainly encapsulated using carbohydrates or proteins. So far, oil-in-water emulsification followed by spray-drying were the frequently used techniques for encapsulation of CLA. Further, 4 studies investigated the effects of encapsulated CLA on MetS risk factors compared with non-encapsulated CLA. A limited number of studies investigated the encapsulation of R-TFAs. The effects of encapsulated CLA or R-TFAs on the risk factors for MetS remain understudied; thus, additional studies comparing the effects of encapsulated and non-encapsulated CLA or R-TFAs are needed.

Animal Models in Eye Research: Focus on Corneal Pathologies

The eye is a complex sensory organ that enables visual perception of the world. The dysfunction of any of these tissues can impair vision. Conduction studies on laboratory animals are essential to ensure the safety of therapeutic products directly applied or injected into the eye to treat ocular diseases before eventually proceeding to clinical trials. Among these tissues, the cornea has unique homeostatic and regenerative mechanisms for maintaining transparency and refraction of external light, which are essential for vision. However, being the outermost tissue of the eye and directly exposed to the external environment, the cornea is particularly susceptible to injury and diseases. This review highlights the evidence for selecting appropriate animals to better understand and treat corneal diseases, which rank as the fifth leading cause of blindness worldwide. The development of reliable and human-relevant animal models is, therefore, a valuable research tool for understanding and translating fundamental mechanistic findings, as well as for assessing therapeutic potential in humans. First, this review emphasizes the unique characteristics of animal models used in ocular research. Subsequently, it discusses current animal models associated with human corneal pathologies, their utility in understanding ocular disease mechanisms, and their role as translational models for patients.

Glioblastoma-targeted, local and sustained drug delivery system based on an unconventional lipid nanocapsule hydrogel

The objective of this work was to develop an implantable therapeutic hydrogel that will ensure continuity in treatment between surgery and radiochemotherapy for patients with glioblastoma (GBM). A hydrogel of self-associated gemcitabine-loaded lipid nanocapsules (LNC) has shown therapeutic efficacy in vivo in murine GBM resection models. To improve the targeting of GBM cells, the NFL-TBS.40-63 peptide (NFL), was associated with LNC. The LNC-based hydrogels were formulated with the NFL. The peptide was totally and instantaneously adsorbed at the LNC surface, without modifying the hydrogel mechanical properties, and remained adsorbed to the LNC surface after the hydrogel dissolution. In vitro studies on GBM cell lines showed a faster internalization of the LNC and enhanced cytotoxicity, in the presence of NFL. Finally, in vivo studies in the murine GBM resection model proved that the gemcitabine-loaded LNC with adsorbed NFL could target the non-resected GBM cells and significantly delay or even inhibit the apparition of recurrences.

Enhancing collaboration between geriatricians, oncologists, and pharmacists to optimize medication therapy in older adults with cancer: A position paper from SOFOG-SFPO

Optimizing anticancer treatment and medication therapy in older patients with cancer requires a multidisciplinary approach, with a strong collaboration between geriatricians, oncologists and pharmacists. While all patients can benefit, some clinical situations seem to be high-priority. Careful attention should be given to patients with cardiovascular comorbidities and/or diabetes, which are prone to decompensate during anticancer treatment and often involve multiple medications. Another great concern is the risk of falls, closely related to polypharmacy, hence the need for a comprehensive medication review. Managing the pharmacological treatment of depression is also challenging and require shared expertise. Finally, pharmacists can prove valuable in situations of adherence difficulties or use of complementary medicines. Collaborative practice should begin at initiation of anticancer treatment and continue throughout the care pathway, as continuous reassessment is essential. Although the integration of pharmacists in multidisciplinary teams is often challenged by funding, collaborative should still be strongly encouraged.

Design of experiment and machine learning inform on the 3D printing of hydrogels for biomedical applications

In the biomedical field, 3D printing has the potential to deliver on some of the promises of personalized therapy, notably by enabling point-of-care fabrication of medical devices, dosage forms and bioimplants. To achieve this full potential, a better understanding of the 3D printing processes is necessary, and non-destructive characterization methods must be developed. This study proposes methodologies to optimize the 3D printing parameters for soft material extrusion. We hypothesize that combining image processing with design of experiment (DoE) analyses and machine learning could help obtaining useful information from a quality-by-design perspective. Herein, we investigated the impact of three critical process parameters (printing speed, printing pressure and infill percentage) on three critical quality attributes (gel weight, total surface area and heterogeneity) monitored with a non-destructive methodology. DoE and machine learning were combined to obtain information on the process. This work paves the way for a rational approach to optimize 3D printing parameters in the biomedical field.

Stability of Opened Durvalumab (IMFINZI) Vials. The Beginning of the End of Costly Product Wastage?

Durvalumab is a monoclonal antibody approved for the treatment of lung, urothelial and biliary tract cancers. Durvalumab is supplied in vials as a solution containing no preservatives. Monographs recommend single use of durvalumab vials, and that any leftovers be discarded within 24 h. Thus, significant portions of unused product from opened vials are wasted on a daily basis, generating considerable financial losses. The objective of the present study was to assess the physicochemical and microbiological stability of durvalumab vials kept at 4 °C or room temperature, at 7 and 14 days after opening. Following pH and osmolality measurements, turbidity and submicronic aggregation of durvalumab solution were evaluated by spectrophotometry and dynamic light scattering, respectively. Moreover, steric exclusion high performance liquid chromatography (SE-HPLC), ion exchange HPLC (IEX-HPLC) and peptide mapping HPLC were used to respectively assess aggregation/fragmentation, charge distribution and primary structure of durvalumab. Microbiological stability of durvalumab was evaluated by incubation of vial leftovers on blood agar. All experiments showed physicochemical and microbiological stability of durvalumab vial leftovers for at least 14 days when aseptically handled and kept at either 4 °C or at room temperature. These results suggest the possible extension of utilization of durvalumab vial leftovers well beyond 24 h.

Preserving bone in cancers of the elderly: A necessity

The occurrence of bone fractures is frequent in the elderly population, and in cancer patients, especially with bone metastases. The growing incidence of cancer associated with an aging population implies important health challenges, including bone health. Decisions on cancer care in older adults have to take into account older adults' specificities. Screening tools as G8 or VES 13 and evaluating tools as comprehensive geriatric assessment (CGA) do not include bone-related items. Bone risk assessment is indicated according to identification of geriatric syndromes such as falls, history, and the oncology treatment plan. Some cancer treatments disrupt bone turnover and decrease bone mineral density. This is mainly caused by hypogonadism, induced by hormonal treatments and some chemotherapies. Treatments can also cause direct (i.e., chemotherapy, radiotherapy or glucocorticoids) or indirect toxicity through electrolyte disorders (i.e., some chemotherapies or tyrosine kinase inhibitors) on bone turnover. Bone risk prevention is multidisciplinary. Certain interventions proposed in the CGA aim to improve bone health and reduce the risk of falling. It is also based on the drug management of osteoporosis, and the prevention of complications from bone metastases. Management of fractures, related or not to bone metastases relates to the concept of orthogeriatrics. It is also based on the benefit-risk ratio of the operation, access to minimally invasive techniques, prehabilitation or rehabilitation, but also the prognosis related to cancer and geriatric syndromes. Bone health is essential in older cancer patient's care. Bone risk assessment should be part of CGA in routine use and specific decision-making tools should be developed. Bone event management must be integrated throughout the patient's care pathway and oncogeriatrics multidisciplinarity should include rheumatological expertise.

Effects of Proton Pump Inhibitors Intake During Chemoradiotherapy for Rectal Cancer: a Retrospective Cohort Study

PURPOSE

Proton pump inhibitors (PPIs) are one of the most widely used drugs worldwide and are involved in several drug interactions. Recently, several studies have suggested that PPIs may interfere with the efficacy of capecitabine. This study primarily aimed to investigate the effects of PPI intake on the pathologic response rate of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy with capecitabine.

METHOD

A retrospective study was conducted at a French Comprehensive Cancer Center. Patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by surgery were included in the study. Demographic parameters, treatment characteristics, survival data, and PPI intake data were collected. Frequencies and percentages were reported for categorical variables and medians and interquartile ranges for continuous variables. Distribution of variables was compared according to PPI treatment using the chi-square test or Fisher's exact test for categorical data and nonparametric Wilcoxon tests for continuous variables. Survival data were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

In total, 215 patients were included, of whom 135 (62.8%) were men. The PPI intake frequency was 16.1%. The rate of complete pathological response was not significantly lower in patients on PPIs than in those not on PPIs (8.7% vs. 19%, p = 0.36). PPI intake was not associated with a statistically significant decrease in recurrence-free survival (hazard ratio [HR] = 1.26, 95% confidence interval [CI] 0.61-2.60, p = 0.54) or overall survival (HR = 0.95, 95% CI 0.33-2.76, p = 0.93).

CONCLUSION

No significant association was observed between PPI co-medication and complete pathological response or survival in patients treated for locally advanced rectal cancer. However, the safety of PPIs could not be confirmed. Further ancillary studies of prospective clinical trials or studies using the Health Data Hub are necessary to explore the effects of PPIs on rectal cancer more accurately.

Projecting overall survival in health-economic models: uncertainty and maturity of data

OBJECTIVE

As lifetime horizons are considered for economic evaluations, the Kaplan-Meier (KM) estimate is used to extrapolate survival in cases of immature overall survival (OS) data. This study estimated the error induced by the choice of distribution when extrapolating different levels of OS maturity.

METHODS

Fifteen phase 3 trials reporting KM estimates of OS where at least 70% maturity (i.e. 70% of the population had died during follow-up) were included and compared to artificially created truncated data (30 and 50% maturity). Individual patient-data were reproduced using the Guyot algorithm based on digitized KM curves. Parametric survival distributions were fit for each arm in each study, for each maturity level, using the same time horizon (equal to the maximum follow-up). For each KM curve, the best distribution was chosen based on visual inspection, Akaike/Bayesian information criteria, and external validity. Outcomes were measured as life expectancy in months (LM) and life months gained (LMG).

RESULTS

The Weibull (33%), log-logistic (32%) and log-normal (27%) were most often selected as the best fitting distribution. Compared to LM at full maturity, LM was overestimated in 23 and 40% of cases, at 30 and 50% maturity, respectively. Mean absolute error was 2.12months at 30% maturity, and decreased to 0.88months at 50% maturity. When comparing to mature data, the mean percentage of error in LMG was 126.4 and 62.4% at 30 and 50% maturity, respectively.

CONCLUSION

The extent of OS maturity increases the risk of error when projecting long-term life expectancy for economic models. Even marginal gains in OS maturity result in more accurate estimations and should be considered when developing models.

Diabetes is associated with high risk of severe adverse events during chemotherapy for cancer patients: A single-center study

Diabetes mellitus (DM) is a common comorbidity among cancer patients, but its impact on chemotherapy tolerance has not been widely studied. We aimed to compare the occurrence of severe grade 3/4 adverse events (G3/4 AEs) within 90 days of starting chemotherapy between patients with and without diabetes. We conducted a retrospective single-center study in Lille University Hospital Oncology Department, France. Patients who received the first cycle of chemotherapy for gastrointestinal, gynecological or cancer of unknown primary source between 1 May 2013 and 1 May 2016, were included. Overall, 609 patients were enrolled: 490 patients without diabetes (80.5%) and 119 patients with diabetes (19.5%). Within 90 days of starting chemotherapy, patients with diabetes had a significantly higher occurrence of AEs G3/4 compared to those with no diabetes (multivariate odds ratio [OR]: 1.57 [1.02-2.42], P = .04). More frequent G3/4 AEs in patients with diabetes were infection (26%), hematological disorders (13%), endocrine disorders (13%) and deterioration of the general condition (13%). In the year following the beginning of chemotherapy, patients with diabetes were twice as likely to be hospitalized as those without diabetes (univariate OR: 2.1 [1.40-3.15], P = .0003). After multivariate adjustment, diabetes was no longer significantly associated with the risk of hospitalization (P = .051). There were no differences between patients with and without diabetes regarding dose reduction and chemotherapy treatment delays (P = .61 and P = .30, respectively). Our study suggests the need for better consideration of DM in the personalized care plan to improve chemotherapy tolerance and quality of life of patients with DM.

The mechanisms of anti-PEG immune response are different in the spleen and the lymph nodes

Polyethylene glycol (PEG) is a common ingredient in nanomedicines and pharmaceuticals. Recent studies show that approximately 20-70% of humans have anti-PEG antibodies that can recognize the polymer. Because these anti-PEG antibodies can reduce the effectiveness of certain PEGylated therapeutics, understanding how these immunoglobulins are produced is important. In this work, we investigate the mechanisms of the anti-PEG immune response, following the injection of polymeric nanoparticles by different routes of administration. We observed that the extent of systemic absorption and splenic deposition cannot predict the production of anti-PEG IgM - possibly because redundant biological pathways can be involved. Data obtained by surgically removing the spleen or depleting the complement activity suggest that the mechanisms behind the anti-PEG immune response differ between intravenous and subcutaneous injections. While B cells from the spleen appear to necessitate complement proteins to interact with nanoparticles, internalization by follicular B cells from the lymph nodes is unaffected by depletion of the cascade. This study confirms that the biological mechanisms involved in the immune recognition of nanomedicines varies based on the administration route. This knowledge can be utilized to use nanomedicines to engage the immune system in differentiated ways.

Taste Preference Between Ruminant and Industrial Trans Fat in C57BL/6 Mice Measured With the Automated IntelliCage System

Objectives

The objective is to evaluate the taste preference between water, lecithin, R-TFA and I-TFA (TFAs in lecithin at a ratio of 14:86 (w/w)) nanovesicles measured with the automated IntelliCage system in C57BL/6 mice. We hypothesized that the preference for industrially originated trans-fatty acids (elaidic acid (EA trans 18: 1n-9)) and ruminant trans fatty acids (trans-palmitoleic acid (TPA t16:1 n-7)) -is higher than lecithin (control) and/or water. The objective is to evaluate the taste preference between water, lecithin, R-TFA and I-TFA (TFAs in lecithin at a ratio of 14:86 (w/w)) nanovesicles measured with the automated IntelliCage system in C57BL/6 mice.

Methods

Twenty-four female C57BL/6 mice were divided into 2 groups in two separate IntelliCages where had ad libitum access to food (Teklad global 18% protein extruded (18% fat)). On week 1, both groups had access to only water (control). On week 2, in cage 1 mice received lecithin and EA and in cage 2 mice received lecithin and TPA. In week 3 mice had access to only water. On weeks 4 and 5, mice had access to EA and TPA where the positions of trans fatty acids were interchanged for week 5 compared to week 4. Water also was added to the cages on week 5. Mice weights were measured for each week. Corner preference was recorded by 1- the number of the times a mouse enters a corner (corners visits), 2- crossing a hole to reach the bottles (nose pokes); and 3-the number of licking the bottles (licks). Differences between total number of licks was assessed by t-test.

Results

During week 2, mice preferred either EA (7.6 times) in cage 1 or TPA (7.9 times) in cage 2 over lecithin (P < 0.05). During week 4 in cage 1, the mice drank more EA (3.14 times) compared to TPA (P < 0.05). Oppositely during week 4, in cage 2, mice drank more TPA compared to EA (1,2 times, P < 0.05). After corners were switched for fat solutions in week 5, mice drank TPA 2.66 times more than EA (P < 0.05) and 3.5 times more than water (P < 0.05) in cage 1. Equally in cage 2, mice drank EA 1.44 and 4.4 times more than TPA and water (P < 0.05) in week 5.

Conclusions

Results showed mice preferred dietary trans fat, either EA and TPA in equal matter over control and drinking water. Further, mice changed their fat preference (EA to TPA and TPA to EA) when the positions of trans fatty acids in corners were switched; therefore, more analysis needs to be done.

Funding Sources

NSERC, CMDO.

Isolating Nanoparticles from Complex Biological Media by Immunoprecipitation

Polyethylene glycol (PEG) is considered the gold standard to prepare long circulating nanoparticles. The hydrophilic layer that sterically protects PEGylated nanomedicines also impedes their separation from biological media. In this study, we describe an immunoprecipitation method using AntiPEG antibodies cross-linked to magnetic beads to extract three types of radiolabeled PEGylated systems: polymeric nanoparticles, liposomes, and therapeutic proteins. The potential of the method is emphasized by isolating these systems after in vivo administration and ex vivo incubation in human biological fluids. Immunoprecipitation also allows a unique perspective on the size distribution of nanoparticles in the bloodstream after intravenous and intraperitoneal administrations. Further, we highlight the potential of the approach to inform on nanomaterial-associated drug in plasma as well as help characterize the protein corona. Altogether, we believe this method answers an unmet need in nanomedicine research and will contribute a fresh perspective on the interactions of nanomedicines with biological systems.

Effects of Industrial and Ruminant Trans-fatty Acids-Enriched Diet on Fecal Microbiome and Short Chain Fatty Acid Metabolites of C57BL/6 Mice

Objectives

We hypothesized that the intake of industrially originated trans-fatty acids (elaidic acid (EA trans 18: 1n-9)) and ruminant trans fatty acids (trans-palmitoleic acid (TPA t16:1 n-7)) will differentially modify gut microbiota and short-chain fatty acids (SCFA) profiles. The objective is to compare the long- and short-term effects of EA and TPA on the fecal microbiome and SCFAs profiles in mice.

Methods

Forty C57BL/6 mice were divided to 4 groups. Each group was given one of the following 4 formulations in the drinking water: lecithin nanovesicles, nanovesicles containing either lecithin with EA or TPA (86:14 (w/w)) or water alone (control) for 28 days with a normal fat diet. Fecal samples were collected at days 0, 7 and 28. Gut microbiota profiles were determined by 16S rRNA gene sequencing. SCFAs were measured by headspace gas chromatography coupled to a single quadrupole mass spectrometer. Baseline data (relative abundance of bacteria or levels of SCFAs) was pooled and then compared with data from day 7 or day 28 for each formulation.

Results

After 7 days of lecithin, 16S rRNA analysis revealed an increase in the relative abundance of Lactobacillus. After 28 days of lecithin, an increase in the relative abundance of Lactobacillus, Erysipelotrichaceae, and Enterobacteriaceae together with a decrease in Bacteroidaceae was observed. Further, a tendency to increase level of butyric acid (P = 0.053) was observed after 28 days of lecithin. After 7 days of EA, an increase in the relative abundance of Lactobacillus, whereas a decrease in the relative abundance of Parabacteroides, Bacteroides, Rumininococcaceae, Lachnospiraceae and Peptococcaceae was observed. After 7 days of TPA, results show a decreased level of isovaleric acid (P = 0.04) and valeric acid (P = 0.03). After 28 days of TPA, data demonstrates an increase in the level of butyric acid (P = 0.01) and propionic acid (P = 0.01). Water intake for 28 days decreased the level of valeric acid (P = 0.02).

Conclusions

Consumption of industrial and ruminant trans-fatty acids modify differentially bacterial taxa present in the gut microbiome and SCFA profiles.

Funding Sources

NSERC, CMDO.

Efficacy and tolerance of gemcitabine and nab-paclitaxel in elderly patients with advanced pancreatic ductal adenocarcinoma

BACKGROUND

The efficacy and safety of gemcitabine and nab-paclitaxel (GnP) among elderly patients with advanced pancreatic ductal adenocarcinoma (PDAC) remains poorly understood. We aimed to evaluate the safety and efficacy of GnP in this setting.

PATIENTS AND METHODS

We retrospectively included all consecutive patients aged ≥65 years with histologically proven PDAC who received at least one cycle of GnP (January 2014 to May 2018) in four academic centers. The primary endpoints were toxicity and overall survival (OS). Secondary endpoints were progression-free survival (PFS) and objective response rate. We compared patients aged ≥ or <75 years.

RESULTS

The study included 127 patients; among them 42 (33.1%) were aged ≥ 75 years. Fifty-seven and seventy patients received GnP as the first-line and the second-line treatment or beyond, respectively. Sixty-seven patients had at least one grade 3/4 adverse event, the most frequent being neutropenia and peripheral neuropathy. No deaths were related to toxicity. OS (median, 8.0 months; 95% confidence interval (CI), 5.8-10.2) and PFS (median, 5.5 months; 95% CI, 4.8-6.2) were similar for patients aged <75 or ≥75 years in the whole cohort and among patients receiving GnP as the first-line treatment. Cephalic PDAC, liver metastases, hypoalbuminemia, and GnP received beyond the first-line were associated with a significantly shorter OS on the multivariate analysis.

CONCLUSION

GnP is well tolerated and effective in elderly patients with advanced PDAC, even patients aged ≥75 years. The data from daily clinical practice are consistent with the results reported with first-line treatment and highlight the relevance of GnP administration in elderly patients.

Vismodegib in neoadjuvant treatment of locally advanced basal cell carcinoma: First results of a multicenter, open-label, phase 2 trial (VISMONEO study): Neoadjuvant Vismodegib in Locally Advanced Basal Cell Carcinoma

BACKGROUND

Surgery is the primary treatment for basal cell carcinoma (BCC). In locally advanced basal cell carcinoma (laBCC), surgery may cause functional or aesthetic damage. In laBCC, neoadjuvant administration of vismodegib, an inhibitor of the Hedgehog signaling pathway, may reduce tumor size, facilitate resection, and reduce functional and aesthetic consequences of surgery. The VISMONEO study assessed efficacy and safety of vismodegib in neoadjuvant treatment of laBCC.

METHODS

VISMONEO (NCT02667574) is an open-label, noncomparative, multicenter, phase 2 study. Patients with ≥1 histologically confirmed facial BCC, inoperable or operable with functional or major aesthetic sequelae risk, were included. Oral vismodegib 150 mg was administered once daily for 4 to 10 months before planned surgery, which was performed once the best response under vismodegib was observed. Primary endpoint was percentage of patients with BCC with tumor downstaging following surgical resection after neoadjuvant vismodegib. Downstaging was defined according to a 6-stage surgical classification related to the aesthetic and functional consequences of surgery.

FINDINGS

55 patients (median age: 73 years) with laBCC were included from November 2014 to June 2015. At inclusion, 4 patients were inoperable, 15 were operable with a major functional risk, and 36 were operable with a minor functional risk or a major aesthetic risk. Mean size of target lesion was 47.3 mm (SD: 27.2 mm). 44 patients presented with downstaging after vismodegib treatment (80%; 95% confidence interval [CI], 67 to 90). Of these 44 patients, 27 had a complete response (25 proved by biopsy). Mean treatment duration was 6.0 months. Overall Response Rate according to RECIST 1.1 criteria was 71% (95% CI, 59 to 88). At 3-years of follow-up, 16/44 patients had known recurrence (36%; 95%CI, 22 to 51).

INTERPRETATION

Neoadjuvant vismodegib allows for a downstaging of the surgical procedure for laBCCs in functionally sensitive locations.

FUNDING

VISMONEO was funded by F. Hoffmann-La Roche Ltd.

Innate and adaptive immune responses toward nanomedicines

Since the commercialization of the first liposomes used for drug delivery, Doxil/Caelyx® and Myocet®, tremendous progress has been made in understanding interactions between nanomedicines and biological systems. Fundamental work at the interface of engineering and medicine has allowed nanomedicines to deliver therapeutic small molecules and nucleic acids more efficiently. While nanomedicines are used in oncology for immunotherapy or to deliver combinations of cytotoxics, the clinical successes of gene silencing approaches like patisiran lipid complexes (Onpattro®) have paved the way for a variety of therapies beyond cancer. In parallel, the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has highlighted the potential of mRNA vaccines to develop immunization strategies at unprecedented speed. To rationally design therapeutic and vaccines, chemists, materials scientists, and drug delivery experts need to better understand how nanotechnologies interact with the immune system. This review presents a comprehensive overview of the innate and adaptative immune systems and emphasizes the intricate mechanisms through which nanomedicines interact with these biological functions.

Is the survival of patients treated with ipilimumab affected by antibiotics? An analysis of 1585 patients from the French National hospital discharge summary database (PMSI)

Background: The gut microbiota has a key role in the regulation of the immune system. Disruption of the gut microbiota’s composition by antibiotics might significantly affect the efficacy of immune checkpoint inhibitors. In a study of patients treated with ipilimumab, we sought to assess the relationship between overall survival and in-hospital antibiotic administration.

Methods: Patients having been treated with ipilimumab between January 2012 and November 2014 were selected from the French National Hospital Discharge Summary Database. Exposure to antibiotics was defined as the presence of a hospital stay with a documented systemic bacterial infection in the 2 months before or the month after initiation of the patient’s first ever course of ipilimumab. The primary outcome was overall survival.

Results: We studied 43,124 hospital stays involving 1585 patients from 97 centers. All patients had received ipilimumab monotherapy for advanced melanoma. Overall, 117 of the 1585 patients (7.4%) were documented as having received systemic antibiotic therapy in hospital during the defined exposure period. The median overall survival time was shorter in patients with infection (6.3 months, vs. 15.4 months in patients without an infection; hazard ratio (HR) = 1.88, 95% confidence interval [1.46; 2.43], p = 10⁻⁶). In a multivariate analysis adjusted for covariates, infection was still significantly associated with overall survival (HR = 1.68, [1.30; 2.18], p = 10⁻⁵).

Conclusions: In patients treated with ipilimumab for advanced melanoma, infection, and antibiotic administration in hospital at around the time of the patient’s first ever course of ipilimumab appears to be associated with significantly lower clinical benefit.

Role of the complement cascade in the biological fate of liposomes in rodents

Nanomedicines, including liposomes, have been used to improve the clinical efficacy and safety of drugs. In some liposomal formulations, a hydrophilic polymer coating of poly(ethylene glycol) (PEG) is used to increase the circulation time. Understanding the biological mechanisms responsible for the clearance of PEGylated and non-PEGylated nanomedicines is necessary to develop better-performing materials. The purpose of this work is to explore the role of complement in the elimination of intravenously administered liposomes (PEGylated and non-PEGylated) in mice and rats. Here, the complement cascade was depleted by intraperitoneal injections of cobra venom factor (CVF) 12 and 24 hours before the intravenous injection of radiolabeled liposomes. In both mice and rats, non-PEGylated liposomes showed faster elimination than PEGylated liposomes. At a lipid dose of 20 mg kg^-1, the abrogation of the complement cascade (in CVF group) did not alter the circulation time of either PEGylated or non-PEGylated liposomes. In contrast, at lower doses (2 mg kg^-1), animals treated with CVF had slightly higher levels of circulating liposomes, especially during the 24 hours pharmacokinetic studies. The complement cascade seems to govern the uptake of non-PEGylated liposomes by splenic B cells. Altogether, these results suggest that although PEGylated and non-PEGylated liposomes can activate complement, the impact of this cascade on their circulation time is minor and mostly perceivable at later phases of distribution. This work enlightens biological pathways responsible for in vivo clearance of liposomes and will help in orienting future research in elucidating the nano-bio interface.

Drinkable lecithin nanovesicles to study the biological effects of individual hydrophobic macronutrients and food preferences

Fundamental nutritional studies on bioactive molecules require minimizing exposure to confounding foreign elements, like solvents. Herein, aqueous formulations of lecithin nanovesicles are proposed to study three individual trans fatty acids relevant to human nutrition: elaidic acid, trans-vaccenic acid and trans-palmitoleic acid. This proof-of-concept study describes the encapsulation of fatty acids, in vivo bioavailability, and the use of nanovesicles in behavioral experiments. The oral bioavailability of the encapsulated molecules and the selective exposure of animals to each trans-fatty acid of interest were confirmed in healthy rats. Behavioral studies also evidenced that nanovesicles can be used to evaluate the palatability of the lipids and investigate food preferences in mice. Altogether this study shows that lecithin nanovesicles offer an elegant tool to efficiently deliver hydrophobic molecules to animal models. This approach paves the way for future studies deconvoluting the nutritional effects of trans-fatty acids.

External Validation of an MRI-Derived Radiomics Model to Predict Biochemical Recurrence after Surgery for High-Risk Prostate Cancer

Adjuvant radiotherapy after prostatectomy was recently challenged by early salvage radiotherapy, which highlighted the need for biomarkers to improve risk stratification. Therefore, we developed an MRI ADC map-derived radiomics model to predict biochemical recurrence (BCR) and BCR-free survival (bRFS) after surgery. Our goal in this work was to externally validate this radiomics-based prediction model.

EXPERIMENTAL DESIGN

A total of 195 patients with a high recurrence risk of prostate cancer (pT3-4 and/or R1 and/or Gleason's score > 7) were retrospectively included in two institutions. Patients with postoperative PSA (Prostate Specific Antigen) > 0.04 ng/mL or lymph node involvement were excluded. Radiomics features were extracted from T2 and ADC delineated tumors. A total of 107 patients from Institution 1 were used to retrain the previously published model. The retrained model was then applied to 88 patients from Institution 2 for external validation. BCR predictions were evaluated using AUC (Area Under the Curve), accuracy, and bRFS using Kaplan-Meier curves.

RESULTS

With a median follow-up of 46.3 months, 52/195 patients experienced BCR. In the retraining cohort, the clinical prediction model (combining the number of risk factors and postoperative PSA) demonstrated moderate predictive power (accuracy of 63%). The radiomics model (ADC-based SZEGLSZM) predicted BCR with an accuracy of 78% and allowed for significant stratification of patients for bRFS (p < 0.0001). In Institution 2, this radiomics model remained predictive of BCR (accuracy of 0.76%) contrary to the clinical model (accuracy of 0.56%).

CONCLUSIONS

The recently developed MRI ADC map-based radiomics model was validated in terms of its predictive accuracy of BCR and bRFS after prostatectomy in an external cohort.

The European FOOD programme (Fighting Obesity through Offer and Demand)

Key messages

Creating healthier eating patterns during the working day. Making the healthy choice the easy choice.

Projecting overall survival data for health-economic models in oncology: Do maturity levels impact uncertainty?

e18350

Background: A lifetime horizon is recommended for health-economic evaluation of anticancer drugs. If overall survival (OS) data is immature, extrapolation of the Kaplan-Meier (KM) curve using distributions is done to obtain long-term data. Depending on OS maturity, the distribution chosen may impact estimation of life expectancy (LE) and of life years gained (LYG) between treatments. This study aimed to estimate the error (on LE and LYG) induced by the choice of extrapolation distributions, for 2 levels of OS maturity (30% and 50%), as compared to LE and LYG at full maturity. Methods: Fifteen phase 3 trials published between 2013 and 2017 containing OS KM curves were selected if maturity > 70% (Full). To test 2 maturity levels, each KM curve was truncated at 30% and 50%. A 3-step process was performed: 1) KM was digitalized, 2) individual patient-data was reproduced using the Guyot algorithm, and 3) 5 parametric survival distributions were fit using the R-Survival package. For each study, the process was done for each treatment arm and each of the 3 maturity levels on the same time horizon, equal to the maximum follow-up of the study. For each curve, the best distribution was chosen by a board of 2 oncologists and 2 health-economists, based on visual inspection, Akaike/Bayesian Information criteria and external validity. Results: Based on the board review of the 90 KM curves, main chosen distributions were Weibull (33%), Log-logistic (32%) and Log-normal (27%). As compared to LE at full maturity, LE was overestimated in 23% and 40% at 30% and 50% maturity, respectively. Mean absolute error was 0.88 at 30% maturity, and decreased to 2.12 at 50% maturity, i.e. estimation was 2.4 times better from 30% to 50% maturity. On average, at 30% maturity versus full, mean percentage of error in LYG was 126.4% and 62.4% at 50% maturity versus full. Conclusions: The use of immature OS data increases the risk of error when projecting long-term LE. Even marginal gains in OS maturity can be translated in more accurate estimations and guide health-economist in developing models.

Effects of Initial Soil Moisture, Clod Size, and Clay Content on Ammonia Volatilization after Subsurface Band Application of Urea

Ammonia losses from broadcast urea vary based on soil physical and chemical properties; however, less is known about how soil properties affect NH losses after subsurface banding of urea. Therefore, three field trials were established to determine how initial soil moisture, clod size, and clay content affect NH volatilization from subsurface-banded (0.025-m depth) urea using wind tunnels. The first study measured volatilization after banding in a loamy mixed frigid Typic Humaquept at 50, 100, 150, 200, or 250 g kg gravimetric water content (WC). Study 2 measured volatilization from the same soil after covering the bands with soil clods that ranged from <2 to >24 mm in diameter, whereas Study 3 measured volatilization from transplanted, acidic soils with clay contents ranging from 5 to 57%. Cumulative 17-d NH losses for study one ranged from 8.3 to 20.8% of applied N, with the soil wetted to 200 g kg WC experiencing the greatest losses. For Study 2, cumulative NH volatilization losses ranged from 10.8 to 20.8% of applied N, with the greatest losses from the largest clod sizes. For Study 3, NH losses ranged from 2.5 to 51.7% of applied N, with the NH losses correlated to the maximum pH measured in the band ( < 0.001), and to the soil cation exchange capacity ( = 0.054), titratable acidity ( = 0.072), and clay content ( = 0.100). However, the soil with high silt, not sand, content had the highest volatilization losses, suggesting that high silt soils may have the greatest potential for NH volatilization.

T-box genes and retinoic acid signaling regulate the segregation of arterial and venous pole progenitor cells in the murine second heart field

The arterial and venous poles of the mammalian heart are hotspots of congenital heart defects (CHD) such as those observed in 22q11.2 deletion (or DiGeorge) and Holt-Oram syndromes. These regions of the heart are derived from late differentiating cardiac progenitor cells of the Second Heart Field (SHF) located in pharyngeal mesoderm contiguous with the elongating heart tube. The T-box transcription factor Tbx1, encoded by the major 22q11.2 deletion syndrome gene, regulates SHF addition to both cardiac poles from a common progenitor population. Despite the significance of this cellular addition the mechanisms regulating the deployment of common progenitor cells to alternate cardiac poles remain poorly understood. Here we demonstrate that Tbx5, mutated in Holt-Oram syndrome and essential for venous pole development, is activated in Tbx1 expressing cells in the posterior region of the SHF at early stages of heart tube elongation. A subset of the SHF transcriptional program, including Tbx1 expression, is subsequently downregulated in Tbx5 expressing cells, generating a transcriptional boundary between Tbx1-positive arterial pole and Tbx5-positive venous pole progenitor cell populations. We show that normal downregulation of the definitive arterial pole progenitor cell program in the posterior SHF is dependent on both Tbx1 and Tbx5. Furthermore, retinoic acid (RA) signaling is required for Tbx5 activation in Tbx1-positive cells and blocking RA signaling at the time of Tbx5 activation results in atrioventricular septal defects at fetal stages. Our results reveal sequential steps of cardiac progenitor cell patterning and provide mechanistic insights into the origin of common forms of CHD.

Insights into gold nanoparticles as a mucoadhesive system

A large number of drugs are administered on different mucosal surfaces. However, due to the poor mucoadhesion of the current formulations, their bioavailability is often very low. The development of efficient mucoadhesive drug delivery systems is thus crucial for improving the performance of these drugs. The mucoadhesive properties of gold nanoparticles were investigated. First, two types of gold nanoparticles were synthesized: AuNP1 and AuNP2. AuNP1 only contain internal thiol groups on their metallic core, and AuNP2 contain both internal and peripheral thiol groups. Different protocols based on an adapted quantitative colorimetric method, UV-visible and fluorescence spectroscopies were then developed to gather information on their mucoadhesive properties. Moreover, a global correction factor for the inner filter effect in spectrofluorimetry was proposed, and the data obtained were compared to those commonly used in the literature. Mucins deeply interact with AuNP1, perturbing their core, whereas they remain at the periphery of AuNP2. The quantitative method suggests that a larger number of mucins interact with AuNP2. The establishment of this protocol could be applied to assess the mucoadhesive properties of other stable molecules. This mucoadhesive property of gold nanoparticles could be combined with their drug delivery ability in order to improve the medication administered on mucosa.

Induction of endoplasmic reticulum stress by aminosteroid derivative RM-581 leads to tumor regression in PANC-1 xenograft model

The high fatality and morbidity of pancreatic cancer have remained almost unchanged over the last decades and new clinical therapeutic tools are urgently needed. We determined the cytotoxic activity of aminosteroid derivatives RM-133 (androstane) and RM-581 (estrane) in three human pancreatic cancer cell lines (BxPC3, Hs766T and PANC-1). In PANC-1, a similar level of antiproliferative activity was observed for RM-581 and RM-133 (IC₅₀ = 3.9 and 4.3 μM, respectively), but RM-581 provided a higher selectivity index (SI = 12.8) for cancer cells over normal pancreatic cells than RM-133 (SI = 2.8). We also confirmed that RM-581 induces the same ER stress-apoptosis markers (BIP, CHOP and HERP) than RM-133 in PANC-1 cells, pointing out to a similar mechanism of action. Finally, these relevant in vitro results have been successfully translated in vivo by testing RM-581 using different doses (10-60 mg/kg/day) and modes of administration in PANC-1 xenograft models, which have led to tumor regression without any sign of toxicity in mice (animal weight, behavior and histology). Interestingly, RM-581 fully reduced the pancreatic tumor growth when administered orally in mice.

Pharmacokinetic profile of PBRM in rodents, a first selective covalent inhibitor of 17β-HSD1 for breast cancer and endometriosis treatments

The development of a covalent inhibitor of 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1) is a promising approach for the treatment of hormone-dependent breast cancer and endometriosis. After reporting the steroid derivative PBRM as a first potent covalent inhibitor of 17β-HSD1 without estrogenic activity, we are now interested in studying its pharmaceutical behavior. The metabolism study in a human liver microsomal preparation showed a gradual transformation of PBRM into PBRM-O, an oxidized ketonic form of PBRM at position C17. Interestingly, PBRM-O also inhibits 17β-HSD1 and is not estrogenic in estrogen-sensitive T-47D cells. However, when PBRM was injected subcutaneously (sc) in mice, a very small proportion of PBRM-O was measured in a 24 h-time course experiment. A pharmacokinetic study in mice revealed suitable values for half-life (T_1/2 = 3.4 h), clearance (CL = 2088 mL/h kg), distribution volume (Vz = 10.3 L/kg) and absolute bioavailability (F = 65%) when PBRM was injected sc at 14.7 mg/kg. A good F value of 33% was also obtained when PBRM was given orally. A tritiated version of PBRM, ³H-PBRM, was synthesized and used for an in vivo biodistribution study that showed its gradual accumulation in various mouse tissues (peak at 6 h) followed by elimination until complete disappearance after 72 h. Elimination was found to occur in feces (93%) and urine (7%) as revealed by a mass balance experiment. PBRM was also evaluated for its toxicity in mice and it was found to be very well tolerated after weekly sc administration (30-405 mg/kg for 8 weeks) or by po administration (300-900 mg/kg for 4 weeks). Overall, these experiments represent important steps in the preclinical characterization of the pharmaceutical behavior of PBRM, as well as for its translation to clinical trials.

Molecular Rotors for Universal Quantitation of Nanoscale Hydrophobic Interfaces in Microplate Format

Hydrophobic self-assembly pairs diverse chemical precursors and simple formulation processes to access a vast array of functional colloids. Exploration of this design space, however, is stymied by lack of broadly general, high-throughput colloid characterization tools. Here, we show that a narrow structural subset of fluorescent, zwitterionic molecular rotors, dialkylaminostilbazolium sulfonates [DASS] with intermediate-length alkyl tails, fills this major analytical void by quantitatively sensing hydrophobic interfaces in microplate format. DASS dyes supersede existing interfacial probes by avoiding off-target fluorogenic interactions and dye aggregation while preserving hydrophobic partitioning strength. To illustrate the generality of this approach, we demonstrate (i) a microplate-based technique for measuring mass concentration of small (20-200 nm), dilute (submicrogram sensitivity) drug delivery nanoparticles; (ii) elimination of particle size, surfactant chemistry, and throughput constraints on quantifying the complex surfactant/metal oxide adsorption isotherms critical for environmental remediation and enhanced oil recovery; and (iii) more reliable self-assembly onset quantitation for chemically and structurally distinct amphiphiles. These methods could streamline the development of nanotechnologies for a broad range of applications.

Acetamide: a low-cost alternative to alkyl imidazolium chlorides for aluminium-ion batteries

Acetamide forms a room temperature liquid eutectic with AlCl₃, which can be used as a low-cost electrolyte for aluminium-ion batteries.

Identification of single nucleotide polymorphisms of the PI3K-AKT-mTOR pathway as a risk factor of central nervous system metastasis in metastatic breast cancer

INTRODUCTION

The PI3K-AKT-mTOR pathway may be involved in the development of central nervous system (CNS) metastasis from breast cancer. Accordingly, herein we explored whether single nucleotide polymorphisms (SNPs) of this pathway are associated with altered risk of CNS metastasis formation in metastatic breast cancer patients.

METHODS

The GENEOM study (NCT00959556) included blood sample collection from breast cancer patients treated in the neoadjuvant, adjuvant or metastatic setting. We identified patients with CNS metastases for comparison with patients without CNS metastasis, defined as either absence of neurological symptoms or normal brain magnetic resonance imaging (MRI) before death or during 5-year follow-up. Eighty-eight SNPs of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian (or mechanistic) target of rapamycin (mTOR) pathway genes were selected for analysis: AKT1 (17 SNPs), AKT2 (4), FGFR1 (2), mTOR (7), PDK1 (4), PI3KR1 (11), PI3KCA (20), PTEN (17), RPS6KB1 (6).

RESULTS

Of 342 patients with metastases, 207 fulfilled the inclusion criteria: One-hundred-and-seven patients remained free of CNS metastases at last follow-up or date of death whereas 100 patients developed CNS metastases. Among clinical parameters, hormonal and human epidermal growth factor receptor-2 (HER2) status as well as vascular tumour emboli was associated with risk of CNS metastasis. Only PI3KR1-rs706716 was associated with CNS metastasis in univariate analysis after Bonferroni correction (p < 0.00085). Multivariate analysis showed associations between AKT1-rs3803304, AKT2-rs3730050, PDK1-rs11686903 and PI3KR1-rs706716 and CNS metastasis .

CONCLUSION

PI3KR1-rs706716 may be associated with CNS metastasis in metastatic breast cancer patients and could be included in a predictive composite score to detect early CNS metastasis irrespective of breast cancer subtype.