Biofilm-associated metabolism via ERG251 in Candida albicans.

Biofilm formation by the fungal pathogen Candida albicans is the basis for its ability to infect medical devices. The metabolic gene ERG251 has been identified as a target of biofilm transcriptional regulator Efg1, and here we report that ERG251 is required for biofilm formation but not conventional free-living planktonic growth. An erg251Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo catheter infection model. In both in vitro and in vivo biofilm contexts, cell number is reduced and hyphal length is limited. To determine whether the mutant defect is in growth or some other aspect of biofilm development, we examined planktonic cell features in a biofilm-like environment, which was approximated with sealed unshaken cultures. Under those conditions, the erg251Δ/Δ mutation causes defects in growth and hyphal extension. Overexpression in the erg251Δ/Δ mutant of the paralog ERG25, which is normally expressed more weakly than ERG251, partially improves biofilm formation and biofilm hyphal content, as well as growth and hyphal extension in a biofilm-like environment. GC-MS analysis shows that the erg251Δ/Δ mutation causes a defect in ergosterol accumulation when cells are cultivated under biofilm-like conditions, but not under conventional planktonic conditions. Overexpression of ERG25 in the erg251Δ/Δ mutant causes some increase in ergosterol levels. Finally, the hypersensitivity of efg1Δ/Δ mutants to the ergosterol inhibitor fluconazole is reversed by ERG251 overexpression, arguing that reduced ERG251 expression contributes to this efg1Δ/Δ phenotype. Our results indicate that ERG251 is required for biofilm formation because its high expression levels are necessary for ergosterol synthesis in a biofilm-like environment.

Reinforcement amid genetic diversity in the Candida albicans biofilm regulatory network.

Biofilms of the fungal pathogen Candida albicans include abundant long filaments called hyphae. These cells express hypha-associated genes, which specify diverse virulence functions including surface adhesins that ensure biofilm integrity. Biofilm formation, virulence, and hypha-associated gene expression all depend upon the transcription factor Efg1. This transcription factor has been characterized extensively in the C. albicans type strain SC5314 and derivatives, but only recently has its function been explored in other clinical isolates. Here we define a principal set of Efg1-responsive genes whose expression is significantly altered by an efg1Δ/Δ mutation across 17 clinical isolates. This principal gene set includes 68 direct Efg1 targets, whose 5' regions are bound by Efg1 in five clinical isolates, and 42 indirect Efg1 targets, whose 5' regions are not detectably bound by Efg1. Three direct Efg1 target genes encode transcription factors-BRG1, UME6, and WOR3 -whose increased expression in an efg1Δ/Δ mutant restores expression of multiple indirect and direct principal targets, as well as biofilm formation ability. Although BRG1 and UME6 are well known positive regulators of hypha-associated genes and biofilm formation, WOR3 is best known as an antagonist of Efg1 in the sexual mating pathway. We confirm the positive role of WOR3 in biofilm formation with the finding that a wor3Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo biofilm model. Positive control of Efg1 direct target genes by other Efg1 direct target genes-BRG1, UME6, and WOR3 -may buffer principal Efg1-responsive gene expression against the impact of genetic variation in the C. albicans species.

Candida albicans stimulates formation of a multi-receptor complex that mediates epithelial cell invasion during oropharyngeal infection.

Fungal invasion of the oral epithelium is central to the pathogenesis of oropharyngeal candidiasis (OPC). Candida albicans invades the oral epithelium by receptor-induced endocytosis but this process is incompletely understood. We found that C. albicans infection of oral epithelial cells induces c-Met to form a multi-protein complex with E-cadherin and the epidermal growth factor receptor (EGFR). E-cadherin is necessary for C. albicans to activate both c-Met and EGFR and to induce the endocytosis of C. albicans. Proteomics analysis revealed that c-Met interacts with C. albicans Hyr1, Als3 and Ssa1. Both Hyr1 and Als3 are required for C. albicans to stimulate c-Met and EGFR in oral epithelial cells in vitro and for full virulence during OPC in mice. Treating mice with small molecule inhibitors of c-Met and EGFR ameliorates OPC, demonstrating the potential therapeutic efficacy of blocking these host receptors for C. albicans.

Glucose-enhanced oxidative stress resistance-A protective anticipatory response that enhances the fitness of Candida albicans during systemic infection.

Most microbes have developed responses that protect them against stresses relevant to their niches. Some that inhabit reasonably predictable environments have evolved anticipatory responses that protect against impending stresses that are likely to be encountered in their niches-termed "adaptive prediction". Unlike yeasts such as Saccharomyces cerevisiae, Kluyveromyces lactis and Yarrowia lipolytica and other pathogenic Candida species we examined, the major fungal pathogen of humans, Candida albicans, activates an oxidative stress response following exposure to physiological glucose levels before an oxidative stress is even encountered. Why? Using competition assays with isogenic barcoded strains, we show that "glucose-enhanced oxidative stress resistance" phenotype enhances the fitness of C. albicans during neutrophil attack and during systemic infection in mice. This anticipatory response is dependent on glucose signalling rather than glucose metabolism. Our analysis of C. albicans signalling mutants reveals that the phenotype is not dependent on the sugar receptor repressor pathway, but is modulated by the glucose repression pathway and down-regulated by the cyclic AMP-protein kinase A pathway. Changes in catalase or glutathione levels do not correlate with the phenotype, but resistance to hydrogen peroxide is dependent on glucose-enhanced trehalose accumulation. The data suggest that the evolution of this anticipatory response has involved the recruitment of conserved signalling pathways and downstream cellular responses, and that this phenotype protects C. albicans from innate immune killing, thereby promoting the fitness of C. albicans in host niches.

A common vesicle proteome drives fungal biofilm development.

Extracellular vesicles mediate community interactions among cells ranging from unicellular microbes to complex vertebrates. Extracellular vesicles of the fungal pathogen Candida albicans are vital for biofilm communities to produce matrix, which confers environmental protection and modulates community dispersion. Infections are increasingly due to diverse Candida species, such as the emerging pathogen Candida auris, as well as mixed Candida communities. Here, we define the composition and function of biofilm-associated vesicles among five species across the Candida genus. We find similarities in vesicle size and release over the biofilm lifespan. Whereas overall cargo proteomes differ dramatically among species, a group of 36 common proteins is enriched for orthologs of C. albicans biofilm mediators. To understand the function of this set of proteins, we asked whether mutants in select components were important for key biofilm processes, including drug tolerance and dispersion. We found that the majority of these cargo components impact one or both biofilm processes across all five species. Exogenous delivery of wild-type vesicle cargo returned mutant phenotypes toward wild type. To assess the impact of vesicle cargo on interspecies interactions, we performed cross-species vesicle addition and observed functional complementation for both biofilm phenotypes. We explored the biologic relevance of this cross-species biofilm interaction in mixed species and mutant studies examining the drug-resistance phenotype. We found a majority of biofilm interactions among species restored the community's wild-type behavior. Our studies indicate that vesicles influence the development of protective monomicrobial and mixed microbial biofilm communities.

Physician knowledge, practice patterns, and barriers encountered regarding guideline-concordant use of bone modifying agents for prostate cancer.

BACKGROUND: Guidelines recommend bone-modifying agents (BMAs) for patients with castrate-resistant prostate cancer (CRPC) and bone metastasis, but not for castrate-sensitive prostate cancer (CSPC). Physicians beliefs and practices regarding BMA therapy are poorly understood. METHODS: This was a qualitative interview study with embedded Likert-scale elements. Study participants were physicians who treat prostate cancer, located within an academic cancer center or an affiliated community-based network. Participants were asked about their experiences and practice patterns regarding BMA therapy. Participants used Likert-scale items to identify the most common barriers to guideline-concordant BMA use and the most effective potential interventions. Participants were subsequently asked to rank the three most common barriers and the three most effective interventions to reduce underuse (for CRPC) and overuse (for CSPC). RESULTS: Nineteen physicians were invited and 15 participated; one physician did not answer some questions as outside of their practice scope. All were aware of the recommendation for BMAs in CRPC. 14% (2/14) were unaware of the recommendation against BMA use for CSPC; an additional 29% (4/14) believed that BMA use could be appropriate for CSPC depending on the metastatic disease burden. 36% (5/14) were unaware of recommendations for screening and treatment of low bone mineral density. The most common barriers (occurring "often" or "sometimes") were obtaining dental clearance (11/15) and insufficient clinic time (6/15). The interventions identified as most effective to reduce underuse were dental navigation (11/15) and electronic medical record (EMR)-based guidance (9/15). The interventions identified as most effective to reduce overuse were peer-to-peer education (14/15) and EMR-based guidance (13/15). CONCLUSIONS: Awareness of guideline recommendations for screening and treatment of low bone mineral density and against BMA use for CSPC was good, but not complete. Dental navigation, peer-to-peer education, and EMR-based guidance were preferred intervention strategies to improve guideline-concordant use.

Commercial Versus Medicaid Insurance and Use of High-Priced Anticancer Treatments.

BACKGROUND: Because the markups on cancer drugs vary by payor, providers' financial incentive to use high-price drugs is differential according to each patient's insurance type. We evaluated the association between patient insurer (commercial vs Medicaid) and the use of high-priced cancer treatments. MATERIALS AND METHODS: We linked cancer registry, administrative claims, and demographic data for individuals diagnosed with cancer in North Carolina from 2004 to 2011, with either commercial or Medicaid insurance. We selected cancers with multiple FDA-approved, guideline-recommended chemotherapy options and large price differences between treatment options: advanced colorectal, lung, and head and neck cancer. The outcome was a receipt of a higher-priced option, and the exposure was insurer: commercial versus Medicaid. We estimated risk ratios (RRs) for the association between insurer and higher-priced treatment using log-binomial models with inverse probability of exposure weights. RESULTS: Of 812 patients, 209 (26%) had Medicaid. The unadjusted risk of receiving higher-priced treatment was 36% (215/603) for commercially insured and 27% (57/209) for Medicaid insured (RR: 1.31, 95% CI: 1.02-1.67). After adjustment for confounders the association was attenuated (RR: 1.15, 95% CI: 0.81-1.65). Exploratory subgroup analysis suggested that commercial insurance was associated with increased receipt of higher-priced treatment among patients treated by non-NCI-designated providers (RR: 1.53, 95% CI: 1.14-2.04). CONCLUSIONS: Individuals with Medicaid and commercial insurance received high-priced treatments in similar proportion, after accounting for differences in case mix. However, modification by provider characteristics suggests that insurance type may influence treatment selection for some patient groups. Further work is needed to determine the relationship between insurance status and newer, high-price drugs such as immune-oncology agents.

Serum bridging molecules drive candidal invasion of human but not mouse endothelial cells.

During hematogenously disseminated candidiasis, blood borne fungi must invade the endothelial cells that line the blood vessels to infect the deep tissues. Although Candida albicans, which forms hyphae, readily invades endothelial cells, other medically important species of Candida are poorly invasive in standard in vitro assays and have low virulence in immunocompetent mouse models of disseminated infection. Here, we show that Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei can bind to vitronectin and high molecular weight kininogen present in human serum. Acting as bridging molecules, vitronectin and kininogen bind to αv integrins and the globular C1q receptor (gC1qR), inducing human endothelial cells to endocytose the fungus. This mechanism of endothelial cell invasion is poorly supported by mouse endothelial cells but can be restored when mouse endothelial cells are engineered to express human gC1qR or αv integrin. Overall, these data indicate that bridging molecule-mediated endocytosis is a common pathogenic strategy used by many medically important Candida spp. to invade human vascular endothelial cells.

Activation of EphA2-EGFR signaling in oral epithelial cells by Candida albicans virulence factors.

During oropharyngeal candidiasis (OPC), Candida albicans invades and damages oral epithelial cells, which respond by producing proinflammatory mediators that recruit phagocytes to foci of infection. The ephrin type-A receptor 2 (EphA2) detects ß-glucan and plays a central role in stimulating epithelial cells to release proinflammatory mediators during OPC. The epidermal growth factor receptor (EGFR) also interacts with C. albicans and is known to be activated by the Als3 adhesin/invasin and the candidalysin pore-forming toxin. Here, we investigated the interactions among EphA2, EGFR, Als3 and candidalysin during OPC. We found that EGFR and EphA2 constitutively associate with each other as part of a heteromeric physical complex and are mutually dependent for C. albicans-induced activation. Als3-mediated endocytosis of a C. albicans hypha leads to the formation of an endocytic vacuole where candidalysin accumulates at high concentration. Thus, Als3 potentiates targeting of candidalysin, and both Als3 and candidalysin are required for C. albicans to cause maximal damage to oral epithelial cells, sustain activation of EphA2 and EGFR, and stimulate pro-inflammatory cytokine and chemokine secretion. In the mouse model of OPC, C. albicans-induced production of CXCL1/KC and CCL20 is dependent on the presence of candidalysin and EGFR, but independent of Als3. The production of IL-1α and IL-17A also requires candidalysin but is independent of Als3 and EGFR. The production of TNFα requires Als1, Als3, and candidalysin. Collectively, these results delineate the complex interplay among host cell receptors EphA2 and EGFR and C. albicans virulence factors Als1, Als3 and candidalysin during the induction of OPC and the resulting oral inflammatory response.

Determining Aspergillus fumigatus transcription factor expression and function during invasion of the mammalian lung.

To gain a better understanding of the transcriptional response of Aspergillus fumigatus during invasive pulmonary infection, we used a NanoString nCounter to assess the transcript levels of 467 A. fumigatus genes during growth in the lungs of immunosuppressed mice. These genes included ones known to respond to diverse environmental conditions and those encoding most transcription factors in the A. fumigatus genome. We found that invasive growth in vivo induces a unique transcriptional profile as the organism responds to nutrient limitation and attack by host phagocytes. This in vivo transcriptional response is largely mimicked by in vitro growth in Aspergillus minimal medium that is deficient in nitrogen, iron, and/or zinc. From the transcriptional profiling data, we selected 9 transcription factor genes that were either highly expressed or strongly up-regulated during in vivo growth. Deletion mutants were constructed for each of these genes and assessed for virulence in mice. Two transcription factor genes were found to be required for maximal virulence. One was rlmA, which is required for the organism to achieve maximal fungal burden in the lung. The other was sltA, which regulates of the expression of multiple secondary metabolite gene clusters and mycotoxin genes independently of laeA. Using deletion and overexpression mutants, we determined that the attenuated virulence of the ΔsltA mutant is due in part to decreased expression aspf1, which specifies a ribotoxin, but is not mediated by reduced expression of the fumigaclavine gene cluster or the fumagillin-pseruotin supercluster. Thus, in vivo transcriptional profiling focused on transcription factors genes provides a facile approach to identifying novel virulence regulators.

Roles of Candida albicans Mig1 and Mig2 in glucose repression, pathogenicity traits, and SNF1 essentiality.

Metabolic adaptation is linked to the ability of the opportunistic pathogen Candida albicans to colonize and cause infection in diverse host tissues. One way that C. albicans controls its metabolism is through the glucose repression pathway, where expression of alternative carbon source utilization genes is repressed in the presence of its preferred carbon source, glucose. Here we carry out genetic and gene expression studies that identify transcription factors Mig1 and Mig2 as mediators of glucose repression in C. albicans. The well-studied Mig1/2 orthologs ScMig1/2 mediate glucose repression in the yeast Saccharomyces cerevisiae; our data argue that C. albicans Mig1/2 function similarly as repressors of alternative carbon source utilization genes. However, Mig1/2 functions have several distinctive features in C. albicans. First, Mig1 and Mig2 have more co-equal roles in gene regulation than their S. cerevisiae orthologs. Second, Mig1 is regulated at the level of protein accumulation, more akin to ScMig2 than ScMig1. Third, Mig1 and Mig2 are together required for a unique aspect of C. albicans biology, the expression of several pathogenicity traits. Such Mig1/2-dependent traits include the abilities to form hyphae and biofilm, tolerance of cell wall inhibitors, and ability to damage macrophage-like cells and human endothelial cells. Finally, Mig1 is required for a puzzling feature of C. albicans biology that is not shared with S. cerevisiae: the essentiality of the Snf1 protein kinase, a central eukaryotic carbon metabolism regulator. Our results integrate Mig1 and Mig2 into the C. albicans glucose repression pathway and illuminate connections among carbon control, pathogenicity, and Snf1 essentiality.

Physician Payments from Pharmaceutical Companies Related to Cancer Drugs.

BACKGROUND: Drug manufacturers claim that the purpose of financial payments to physicians is to facilitate education about new drugs. This claim suggests 2 testable hypotheses: payments should not be associated with drug revenue and payments for each drug should decline over time as physicians become educated. MATERIALS AND METHODS: We used open payments data on industry payments. We included payments for cancer drugs without generic/biosimilar competitors and used federal data sources to measure Medicare spending (a proxy for overall drug revenue) and a number of prescribers. We used generalized estimating equations (GEE) to model the drug-level association between industry payments and Medicare spending. Separately, we used GEE to estimate the change in payments with respect to the duration of time since initial FDA approval. RESULTS: The sample included 89 drugs and 361 drug-year observations. The total value of industry payments for oncology drugs increased, from $53 333 854 in 2014 to $90 343 731 in 2018. There was no association between log-transformed mean, per-physician industry payments, and per-physician Medicare spending (estimate -0.001, 95%CI, -0.005 to 0.004). Payments for individual drugs decreased over time; estimated payments in the subsequent year for a drug with mean, per-physician payments of $1000 in the index year was: $681* for drugs 0-4 years since approval, $825 for 5-9 years, and $679* for ≥10 years (*P < .05). CONCLUSIONS: Although industry-sponsored education may also serve marketing purposes, the absence of association between industry payments and Medicare spending and the decline in payments subsequent to approval are consistent with claims that industry payments function to facilitate physician education.

The Prescription Drug User Fee Act: Much More Than User Fees.

BACKGROUND: The Prescription Drug User Fee Act (PDUFA) is due for reauthorization in 2022. Beyond creating the user fee program which now generates a majority of the Food and Drug Administration (FDA) Human Drugs Program budget, PDUFA has made numerous additional changes to FDA policy during its 29-year history. FDA's budgetary dependence on user fees may advantage the industry in negotiating favorable policy changes through PDUFA. METHODS: The full texts of all prior PDUFA reauthorization bills and all submitted public comments and meeting minutes for the 2022 reauthorization were reviewed. Provisions affecting FDA regulatory authority and processes were identified. FINDINGS: PDUFA legislation has instituted a broad range of changes to FDA policy, including evidentiary standards for drug approval, accelerated pathways for approval, industry involvement in FDA decision-making, rules regarding industry information dissemination to providers, and market entry of generic drugs. Negotiations over the 2022 reauthorization suggest that industry priorities include increased application of real-world evidence, regulatory certainty, and increased communication between FDA and industry during the drug application process. CONCLUSIONS: The need for PDUFA reauthorization every 5 years has created a recurring legislative vehicle through which far-ranging changes to FDA have been enacted, reshaping the agency's interactions and relationship with the regulated industry. The majority of policy changes enacted through PDUFA legislation have favored industry through decreasing regulatory standards, shortening approval times, and increasing industry involvement in FDA decision-making. FDA's budgetary dependence on the industry, the urgency of each PDUFA reauthorization's passage to maintain uninterrupted funding, and the industry's required participation in PDUFA negotiations may advantage the industry.

Are Financial Payments From the Pharmaceutical Industry Associated With Physician Prescribing? : A Systematic Review.

BACKGROUND: Financial payments from the drug industry to U.S. physicians are common. Payments may influence physicians' clinical decision making and drug prescribing. PURPOSE: To evaluate whether receipt of payments from the drug industry is associated with physician prescribing practices. DATA SOURCES: MEDLINE (Ovid), Embase, the Cochrane Library, Web of Science, and EconLit were searched without language restrictions. The search had no limiting start date and concluded on 16 September 2020. STUDY SELECTION: Studies that estimated the association between receipt of industry payments (exposure) and prescribing (outcome). DATA EXTRACTION: Pairs of reviewers extracted the primary analysis or analyses from each study and evaluated risk of bias (ROB). DATA SYNTHESIS: Thirty-six studies comprising 101 analyses were included. Most studies (n = 30) identified a positive association between payments and prescribing in all analyses; the remainder (n = 6) had a mix of positive and null findings. No study had only null findings. Of 101 individual analyses, 89 identified a positive association. Payments were associated with increased prescribing of the paying company's drug, increased prescribing costs, and increased prescribing of branded drugs. Nine studies assessed and found evidence of a temporal association; 25 assessed and found evidence of a dose-response relationship. LIMITATION: The design was observational, 21 of 36 studies had serious ROB, and publication bias was possible. CONCLUSION: The association between industry payments and physician prescribing was consistent across all studies that have evaluated this association. Findings regarding a temporal association and dose-response suggest a causal relationship. PRIMARY FUNDING SOURCE: National Cancer Institute.

Personal Payments from Pharmaceutical Companies to Authors of Oncology Clinical Practice Guidelines.

BACKGROUND: Oncologists who author clinical practice guidelines frequently have financial relationships with the pharmaceutical industry. It is unknown whether participation on clinical practice guideline committees is associated with differences in the amounts of industry money received. MATERIALS AND METHODS: We conducted a nested case-control study from August 2013 to December 2018. We manually abstracted membership records of National Comprehensive Cancer Network (NCCN) Guidelines committees for the 20 most common cancers and linked to Open Payments. The study sample included medical oncologists selected to join an NCCN Guidelines committee ("joiners") during the study period. Joiners were matched 1:2 to medical oncologists who had no participation on NCCN committees (controls) by gender, NCCN institution, and medical school graduation year. We performed difference-in-differences (DiD) estimation to assess whether selection to an NCCN committee was associated with the dollar value of payments received from industry, using generalized estimating equations to address correlation between matched pairs and between repeated observations of the same pair. RESULTS: During the study period, 54 physicians joined an NCCN Guidelines committee. These physicians received more payments than matched controls in the year prior to joining ($11,259 vs. $3,427; p = .02); this difference did not increase in the year after joining (DiD = $731; p = .45). CONCLUSION: Medical oncologists selected to NCCN Guidelines committees had greater financial ties to industry than their peers. The potential influence of industry in oncology clinical practice guidelines may be reduced through the selection of committee members with fewer ties to industry. IMPLICATIONS FOR PRACTICE: Oncologists who author clinical practice guidelines frequently have financial conflicts of interest with the pharmaceutical industry. This creates concern about the potential for industry influence on guidelines. However, it is unknown whether oncologists who author guidelines have greater industry relationships than their peers. This study compared medical oncologists who were newly selected to join a National Comprehensive Cancer Network (NCCN) Guidelines panel with medical oncologists at the same institutions and at similar career stages. At the time they joined, oncologists joining NCCN Guidelines panels had received more than three times the dollar value of industry payments than their peers. The potential for industry influence may be reduced by the selection of less-conflicted panel members.

Circuit diversification in a biofilm regulatory network.

Genotype-phenotype relationships can vary extensively among members of a species. One cause of this variation is circuit diversification, the alteration of gene regulatory relationships among members of a species. Circuit diversification is thought to be a starting point for the circuit divergence or rewiring that occurs during speciation. How widespread is circuit diversification? Here we address this question with the fungal pathogen Candida albicans, which forms biofilms rich in distinctive hyphal cells as a prelude to infection. Our understanding of the biofilm/hyphal regulatory network comes primarily from studies of one clinical isolate, strain SC5314, and its marked derivatives. We used CRISPR-based methods to create mutations of four key biofilm transcription factor genes-BCR1, UME6, BRG1, and EFG1 -in SC5314 and four additional clinical isolates. Phenotypic analysis revealed that mutations in BCR1 or UME6 have variable impact across strains, while mutations in BRG1 or EFG1 had uniformly severe impact. Gene expression, sampled with Nanostring probes and examined comprehensively for EFG1 via RNA-Seq, indicates that regulatory relationships are highly variable among isolates. Our results suggest that genotype-phenotype relationships vary in this strain panel in part because of differences in control of BRG1 by BCR1, a hypothesis that is supported through engineered constitutive expression of BRG1. Overall, the data show that circuit diversification is the rule, not the exception, in this biofilm/hyphal regulatory network.

Association between Site-of-Care and the Cost and Modality of Radiotherapy for Prostate Cancer: Analysis of Medicare Beneficiaries from 2015 to 2017.

Among 84,447 radiotherapy (RT) courses for Medicare beneficiaries age ≥ 65 with prostate cancer treated with external beam RT (EBRT), brachytherapy, or both, 42,608 (51%) were delivered in hospital-affiliated and 41,695 (49%) in freestanding facilities. Freestanding centers were less likely to use EBRT + brachytherapy than EBRT (OR 0.84 [95%CI 0.84-0.84]; p < .001). Treatment was more costly in freestanding centers (mean difference $2,597 [95%CI $2,475-2,719]; p < .001). Adjusting for modality and fractionation, RT in hospital-affiliated centers was more costly (mean difference $773 [95%CI $693-853]; p < .001). Freestanding centers utilized more expensive RT delivery, but factors unrelated to RT modality or fractionation rendered RT more costly at hospital-affiliated centers.

The Role of Physician Professional Networks in Physicians' Receipt of Pharmaceutical and Medical Device Industries' Payments.

BACKGROUND: Financial relationships between physicians and the pharmaceutical and medical device industries are common, but the factors associated with physicians receiving payments are unknown. OBJECTIVE: The objective of this study is to evaluate the influence of physicians' professional networks' characteristics on the receipt of payments among physicians. DESIGN: Network analysis of cross-sectional data PARTICIPANTS: US physicians who shared Medicare patients with other physicians in 2015 (N=357,813). EXPOSURE (INTERVENTION): Proportion of a physician's professional network that received industry payments and other network characteristics including number of physician connections, how central the physician is within the network, and the tightness of the referral network in which a physician is located. MAIN OUTCOME MEASURES: Relative risk of receiving industry payments. We used modified Poisson regression to control for confounding by gender, time since graduation, practice size, and practice setting (teaching hospital vs. not). We included dummy variables for specialty and hospital referral region level. KEY RESULTS: The proportion of a physician's peers in their professional network that received payments was strongly associated with receipt of pharmaceutical or device industry payments by the physician (top vs bottom quartile aRR=1.28, 95%CI=1.25-1.31). Physician's centrality within a network had a small positive effect on receiving payment (top vs bottom quartile aRR=1.02, 95%CI=1.01-1.04). Network density also had a small negative association with receipt of payment (top vs bottom quartile aRR=0.97, 95%CI=0.96-0.98). CONCLUSIONS: Network characteristics, particularly the receipt of payments among physicians one shares patients with, are associated with whether a physician receives payments. This finding has implications for institutional regulation of industry payments to physicians and demonstrates how institutional policy may impact not only the physicians within the institution but also physicians outside of the institution.

Increasing Financial Payments From Industry to Medical Oncologists in the United States, 2014-2017.

BACKGROUND: Personal payments from the pharmaceutical industry to US physicians are common and are associated with changes in physicians' clinical practice and interpretation of clinical trial results. We assessed temporal trends in industry payments to oncologists, with particular emphasis on payments to authors of oncology clinical practice guideline and on payments related to immunotherapy drugs. METHODS: We included US physicians with active National Plan and Provider Enumeration System records and demographic data available in the Centers for Medicare & Medicaid Services Physician Compare system who had a specialty type of medical oncology or general internal medicine. Medical oncologists serving on NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) Panels were identified manually. Industry payments, and the subset associated with PD-1/PD-L1 drugs, were identified in Open Payments, the federal repository of all transactions of financial value from industry to physicians and teaching hospitals, from 2014 to 2017. RESULTS: There were 13,087 medical oncologists and 85,640 internists who received payments. The mean, annual, per-physician value of payments to oncologists increased from $3,811 in 2014 to $5,854 in 2017, and from $444 to $450 for internists; the median payment increased from $152 to $199 for oncologists and remained at $0 for internists. Oncologists who served on NCCN Guidelines Panels received a greater value in payments and experienced a greater relative increase: mean payments increased from $10,820 in 2014 to $18,977 in 2017, and median payments increased from $500 to $1,366. Among companies marketing PD-1/PD-L1 drugs, mean annual per-oncologist payments associated with PD-1/PD-L1 drugs increased from $28 to $773. Total per-oncologist payments from companies marketing PD-1/PD-L1 drugs experienced a 165% increase from 2014 to 2017, compared with a 31% increase among similar companies not marketing PD-1/PD-L1 drugs. CONCLUSIONS: Pharmaceutical industry payments increased for US oncologists from 2014 to 2017 more than for general internists. The increase was greater among oncologists contributing to clinical practice guidelines and among pharmaceutical companies marketing PD-1/PD-L1 drugs. The increasing flow of money from industry to US oncologists supports ongoing concern regarding commercial interests in guideline development and clinical decision-making.

Use of High-Cost Cancer Treatments in Academic and Nonacademic Practice.

BACKGROUND: Academic physicians, such as those affiliated with National Cancer Institute (NCI)-designated Comprehensive Cancer Centers, may have different practice patterns regarding the use of high-cost cancer drugs than nonacademic physicians. MATERIALS AND METHODS: For this cohort study, we linked cancer registry, administrative, and demographic data for patients with newly diagnosed cancer in North Carolina from 2004 to 2011. We selected cancer types with multiple U.S. Food and Drug Administration-approved, National Comprehensive Cancer Network-recommended treatment options and large differences in reimbursement between higher-priced and lower-priced options (stage IV colorectal, stage IV lung, and stage II-IV head-and-neck cancers). We assessed whether provider's practice setting-NCI-designated Comprehensive Cancer Center ("NCI") versus other location ("non-NCI")-was associated with use of higher-cost treatment options. We used inverse probability of exposure weighting to control for patient characteristics. RESULTS: Of 800 eligible patients, 79.6% were treated in non-NCI settings. Patients treated in non-NCI settings were more likely to receive high-cost treatment than patients treated in NCI settings (36.0% vs. 23.2%), with an unadjusted prevalence difference of 12.7% (95% confidence interval [CI], 5.1%-20.0%). After controlling for potential confounding factors, non-NCI patients remained more likely to receive high-cost treatment, although the strength of association was attenuated (adjusted prevalence difference, 9.6%; 95% CI -0.1%-18.7%). Exploratory analyses suggested potential heterogeneity across cancer type and insurance status. CONCLUSION: Use of higher-cost cancer treatments may be more common in non-NCI than NCI settings. This may reflect differential implementation of clinical evidence, local practice variation, or possibly a response to the reimbursement incentives presented by chemotherapy billing. IMPLICATIONS FOR PRACTICE: Oncology care delivery and practice patterns may vary between care settings. By comparing otherwise similar patients treated in National Cancer Institute (NCI)-designated Comprehensive Cancer Centers with those treated elsewhere, this study suggests that patients may be more likely to receive treatment with certain expensive cancer drugs if treated in the non-NCI setting. These practice differences may result in differences in patient costs and outcomes as a result of where they receive treatment.