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Purpose: To determine, by molecular imaging, how in vivo pharmacodynamics of estrogen-estrogen receptor (ER) binding differ between types of standard endocrine therapy.Experimental Design: The ER has been a highly successful target for breast cancer treatment. ER-directed treatments include lowering ligand concentration by using aromatase inhibitors (AI) and blocking the receptor with agents like tamoxifen (TAM) or fulvestrant (FUL). We measured regional estrogen-ER binding by using positron emission tomography with 18F-fluoroestradiol (FES PET) prior to and during treatment with AI, TAM, or FUL in a series of 30 metastatic breast cancer patients. FES PET measured in vivo estrogen binding at all tumor sites in heavily pretreated women with metastatic bone soft tissue–dominant breast cancer. In patients with uterus (n = 16) changes in uterine FES uptake were also measured.Results: As expected, tumor FES uptake declined more markedly on ER blockers (TAM and FUL, average 54% decline) compared with a less than 15% average decline on estrogen-depleting AIs (P < 0.001). The rate of complete tumor blockade [FES standardized uptake value (SUV) ≤1.5] following TAM (5/5 patients) was greater than the blockade rate following FUL (4/11; 2-sided mid P = 0.019). Percent FES SUV change in the uterus showed a strong association with tumoral change (ρ = 0.63, P = 0.01).Conclusions: FES PET can assess the in vivo pharmacodynamics of ER-targeted agents and may give insight into the activity of established therapeutic agents. Imaging revealed significant differences between agents, including differences in the efficacy of blockade by different ER antagonists in current clinical use. Clin Cancer Res; 17(14); 4799–805. ©2011 AACR.

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Introduction: Radial scar/complex sclerosing lesion (RS/CSL) is a benign breast lesion. The incidence of RS/CSL on core needle biopsy (CNB) ranges from 0.6 to 3.7%. Despite benign pathology, the radiographic appearance of RS/CSL can be indistinguishable from invasive or in situ malignancy. The upgrade rate of RS/CSL to malignancy varies widely. Whether there are RS/CSL on CNB that may be safely observed without surgery is not well understood. Methods: We performed a single center retrospective study of females over 18 with radiology-pathology concordant diagnosis of RS/CSL on CNB from 2015–2020. We excluded patients with ipsilateral or contralateral invasive or in situ malignancy within 3 months prior to or after biopsy proven RS/CSL. Management was immediate surgical excision within 6 months or imaging surveillance. Upgrade rate was determined in the cohort of patients who underwent surgical excision based on evidence of in situ or invasive malignancy. Results: We identified 83 patients with RS/CSL; 56 (67%) underwent surgical excision and 27 (33%) underwent surveillance. Those who underwent surgical excision had a significant higher rate of breast cancer in the family (41% vs 15%, p = 0.02) and concurrent atypia on CNB (16% vs 0%, p = 0.03). After surgical excision, 11 cases upgraded to atypia and one case upgraded to ductal carcinoma in situ. There were no factors associated with upgrade to malignancy. Conclusion: Upgrade rates of RS/CSL to malignancy remain low; however a significant number upgrade to atypia, which offers relevant information for risk stratification. Further research is needed before omission of excision of RS/CSL can be safely considered.

Attaching proteins to surfaces while maintaining bioactivity is a promising avenue for developing new functional materials. This work describes a method to rapidly apply bioactive coatings by conjugating protein into an adhesive network using an ortho-phthaldialdehyde (oPA)-based linker. The polymer matrix was generated using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) polymerization on a commercial, antifouling copper-based paint that had not been previously examined as a catalytic material. After undergoing bioconjugation with the oPA linker, protein was retained at a higher rate on the surface when compared either with the control, which lacked a linker, or with a commercially-available maleimide linker. The ability to apply in situ, polymerize, and adhere biomacromolecules to surfaces while retaining their efficacy enables the creation of novel functional materials with properties usually reserved for the biological domains.

Setaria viridis (green foxtail) is an important model system for improving cereal crops due to its diploid genome, ease of cultivation, and use of C4 photosynthesis. The S. viridis accession ME034V is exceptionally transformable, but the lack of a sequenced genome for this accession has limited its utility. We present a 397 Mb highly contiguous de novo assembly of ME034V using ultra-long nanopore sequencing technology (read N50 = 41kb). We estimate that this genome is largely complete based on our updated k-mer based genome size estimate of 401 Mb for S. viridis. Genome annotation identified 37,908 protein-coding genes and >300k repetitive elements comprising 46% of the genome. We compared the ME034V assembly with two other previously sequenced Setaria genomes as well as to a diversity panel of 235 S. viridis accessions. We found the genome assemblies to be largely syntenic, but numerous unique polymorphic structural variants were discovered. Several ME034V deletions may be associated with recent retrotransposition of copia and gypsy LTR repeat families, as evidenced by their low genotype frequencies in the sampled population. Lastly, we performed a phylogenomic analysis to identify gene families that have expanded in Setaria, including those involved in specialized metabolism and plant defense response. The high continuity of the ME034V genome assembly validates the utility of ultra-long DNA sequencing to improve genetic resources for emerging model organisms. Structural variation present in Setaria illustrates the importance of obtaining the proper genome reference for genetic experiments. Thus, we anticipate that the ME034V genome will be of significant utility for the Setaria research community.

Copper is critically important for methanotrophic bacteria because their primary metabolic enzyme, particulate methane monooxygenase (pMMO), is copper-dependent. In addition to pMMO, many other copper proteins are encoded in the genomes of methanotrophs, including proteins that contain periplasmic copper-A chaperone (PCuAC) domains. Using bioinformatics analyses, we identified three distinct classes of PCuAC domain-containing proteins in methanotrophs, termed PmoF1, PmoF2, and PmoF3. PCuAC domains from other types of bacteria bind a single Cu(I) ion via an HXnMX21/22HXM motif, which is also present in PmoF3, but PmoF1 and PmoF2 lack this motif entirely. Instead, the PCuAC domains of PmoF1 and PmoF2 bind only Cu(II), and PmoF1 binds additional Cu(II) ions in a His-rich extension to its PCuAC domain. Crystal structures of the PmoF1 and PmoF2 PCuAC domains reveal that Cu(II) is coordinated by an N-terminal histidine brace HX10H motif. This binding site is distinct from those of previously characterized PCuAC domains but resembles copper centers in CopC proteins and lytic polysaccharide monooxygenase (LPMO) enzymes. Bioinformatics analysis of the entire PCuAC family reveals previously unappreciated diversity, including sequences that contain both the HXnMX21/22HXM and HX10H motifs, and sequences that lack either set of copper-binding ligands. These findings provide the first characterization of an additional class of copper proteins from methanotrophs, further expand the PCuAC family, and afford new insight into the biological significance of histidine brace-mediated copper coordination.

Purpose Non-atypical papillomas (NAPs) diagnosed on core needle biopsy (CNB) frequently undergo surgical excision due to highly variable upstaging rates. The purpose of this study is to document our dual-institution upgrade rates of NAPs diagnosed on core needle biopsy and review the upgrade rates reported in the literature. Materials and methods Following IRB approval, CNB results from Duke University (7/1/2004–6/30/2014) and the University of North Carolina Chapel Hill (1/1/04–6/30/2013) were reviewed to identify non-atypical papillomas. All cases with surgical excision or 2 years of imaging follow up were included. In addition, a literature review identified 60 published studies on upgrades of NAPs diagnosed at CNB. Cases in our cohort and the published literature were reviewed for confounding factors: [1] missing radiologic-pathologic concordance and/or discordance, [2] papillomas included with high-risk lesions, [3] high risk lesions counted as upgrades, [4] review by a nonspecialized breast pathologist, and [5] cancer incidentally detected. Results Of the 388 CNBs in our dual-institution cohort, 136 (35%) patients underwent surgical excision and 252 (65%) patients had imaging follow up. After controlling for confounders, no cancers (0/388) were found at surgical excision or during follow up imaging. The literature review upstaging rate was 4.0% (166/4157) but 1.8% (4/227) after excluding studies with confounders. The combined upstaging rate from the literature and this study was 0.6% (4/615). Conclusion The upstaging rate for CNB diagnosed NAPs was 0% in our cohort and 0.6% overall after adjusting for confounders. This low rate does not warrant reflexive surgical excision and diagnostic imaging follow up should be discretionary.

Particulate methane monooxygenase (pMMO) is a copper-dependent integral membrane metalloenzyme that converts methane to methanol in methanotrophic bacteria. Studies of isolated pMMO have been hindered by loss of enzymatic activity upon its removal from the native membrane. To characterize pMMO in a membrane-like environment, we reconstituted pMMOs from Methylococcus (Mcc.) capsulatus (Bath) and Methylomicrobium (Mm.) alcaliphilum 20Z into bicelles. Reconstitution into bicelles recovers methane oxidation activity lost upon detergent solubilization and purification without substantial alterations to copper content or copper electronic structure, as observed by electron paramagnetic resonance (EPR) spectroscopy. These findings suggest that loss of pMMO activity upon isolation is due to removal from the membranes rather than caused by loss of the catalytic copper ions. A 2.7 Å resolution crystal structure of pMMO from Mm. alcaliphilum 20Z reveals a mononuclear copper center in the PmoB subunit and indicates that the transmembrane PmoC subunit may be conformationally flexible. Finally, results from extended X-ray absorption fine structure (EXAFS) analysis of pMMO from Mm. alcaliphilum 20Z were consistent with the observed monocopper center in the PmoB subunit. These results underscore the importance of studying membrane proteins in a membrane-like environment and provide valuable insight into pMMO function.

Nature utilizes two groups of enzymes to catalyze methane conversions, methyl-coenzyme M reductases (MCRs) and methane monooxygenases (MMOs). These enzymes have been difficult to incorporate into industrial processes due to their complexity, poor stability, and lack of recombinant tractability. Despite these issues, new ways of preparing and stabilizing these enzymes have recently been discovered, and new mechanistic insight into how MCRs and MMOs break the C-H bond in nature’s most inert hydrocarbon haved been obtained. This review focuses on recent findings in the methane biocatalysis field, and discusses the impact of these finding on designing MMO and MCR-based biotechnologies.

Certain matrix metalloproteinases (MMPs) have the ability to degrade collagen IV, a main component of the breast lobular basement membrane. In this cross-sectional study, we evaluated expression of MMPs 2, 9, and 14 and collagen IV in LCIS and adjacent normal breast tissue among LCIS patients without invasive breast cancer to determine whether expression differed between benign and preinvasive breast epithelial tissue. A total of 64 LCIS patients, diagnosed 2004–2014, were included; 44 had sufficient paired normal tissue for analysis. Marker epithelial expression was measured using immunofluorescence and quantified using the H score (MMPs) or pixel intensity (collagen IV). Associations were evaluated using the Spearman correlation or the Wilcoxon signed-rank test. In LCIS and normal tissue, there was a strong correlation between MMP2 and MMP14 expression (LCIS r = 0.69, normal r = 0.81, both P

Copper is critically important for methanotrophic bacteria because their primary metabolic enzyme, particulate methane monooxygenase (pMMO), is copper-dependent. In addition to pMMO, many other copper proteins are encoded in the genomes of methanotrophs, including proteins that contain periplasmic copper-A chaperone (PCu(A)C) domains. Using bioinformatics analyses, we identified three distinct classes of PCu(A)C domain-containing proteins in methanotrophs, termed PmoF1, PmoF2, and PmoF3. PCu(A)C domains from other types of bacteria bind a single Cu(I) ion via an HX(n)MX(21/22)HXM motif, which is also present in PmoF3, but PmoF1 and PmoF2 lack this motif entirely. Instead, the PCu(A)C domains of PmoF1 and PmoF2 bind only Cu(II), and PmoF1 binds additional Cu(II) ions in a His-rich extension to its PCu(A)C domain. Crystal structures of the PmoF1 and PmoF2 PCu(A)C domains reveal that Cu(II) is coordinated by an N-terminal histidine brace HX(10)H motif. This binding site is distinct from those of previously characterized PCu(A)C domains but resembles copper centers in CopC proteins and lytic polysaccharide monooxygenase (LPMO) enzymes. Bioinformatics analysis of the entire PCu(A)C family reveals previously unappreciated diversity, including sequences that contain both the HX(n)MX(21/22)HXM and HX(10)H motifs, and sequences that lack either set of copper-binding ligands. These findings provide the first characterization of an additional class of copper proteins from methanotrophs, further expand the PCu(A)C family, and afford new insight into the biological significance of histidine brace-mediated copper coordination.

How many metals to oxidize methane? Methane is an important fuel, but there are few direct transformations to partially oxidized products. Bacteria use metalloenzymes to catalyze methane oxidation to methanol, a reaction of industrial interest. Understanding the metal sites that enable this reaction may inspire new biomimetic catalysts. Ross et al. used spectroscopic measurements to assign two monocopper sites in the enzyme particulate methane monooxygenase. These results differ in part from previous proposals for the location and nuclearity of the metal sites and will prompt rethinking about how this metalloenzyme catalyzes methane oxidation. Science , this issue p. 566

Multicopper oxidases (MCOs) are broadly distributed in all kingdoms of life and perform a variety of important oxidative reactions. These enzymes have potential biotechnological applications; however, the applications are impeded by low expression yields in traditional recombinant hosts, solubility issues, and poor copper cofactor assembly. As an alternative to traditional recombinant protein expression, we show the ability to use cell-free protein synthesis (CFPS) to produce complex MCO proteins with high soluble titers. Specifically, we report the production of MCOs in an Escherichia coli-based cell-free transcription-translation system. Total yields as high as 1.2 mg mL(-1) were observed after a 20-h batch reaction. More than 95% of the protein was soluble and activity was obtained by simple post-CFPS addition of copper ions in the form of CuSO4 . Scale-up reactions were achieved from 15 to 100 µL without a decrease in productivity and solubility. CFPS titers were higher than in vivo expression titers and more soluble, avoiding the formation of inclusion bodies. Our work extends the utility of the cell-free platform to the production of active proteins containing copper cofactors and demonstrates a simple method for producing MCOs.

Fibroepithelial lesions with cellular stroma are frequently termed cellular fibroadenomas although criteria for distinguishing them from a phyllodes tumor are vague and subjective. However, the clinical implications and surgical management for these 2 lesions may be different. We randomly selected 21 cases of fibroepithelial lesions sent in consultation to the senior author that were challenging to classify as cellular fibroadenoma or phyllodes tumor. One to 2 representative slides of each case along with patient age were sent to 10 pathologists who specialize in breast pathology. The World Health Organization criteria for phyllodes tumors and a diagnosis form were included with the study set. For the purposes of data reporting, fibroadenoma and cellular fibroadenoma are considered together. In only 2 cases was there uniform agreement as to whether the tumor represented a fibroadenoma or phyllodes tumor. Of the remaining 19 cases, if the diagnoses of fibroadenoma and benign phyllodes tumor were combined and separated from borderline and malignant phyllodes tumors, there was 100% agreement in 53% of cases and 90% agreement in 79% of cases. This study highlights the difficulty that exists in distinguishing some cellular fibroadenomas from phyllodes tumors even for pathologists who specialize in breast pathology. However, there appears to be considerable agreement when cellular fibroadenomas and benign phyllodes tumors are distinguished from borderline and malignant phyllodes tumors. Further studies are needed to determine if there is a clinically significant difference between cellular fibroadenomas and benign phyllodes tumors and how to better distinguish them from borderline and malignant phyllodes tumors.

The ammonia monooxygenase (AMO)/particulate methane monooxygenase (pMMO) superfamily is a diverse group of membrane-bound enzymes of which only pMMO has been characterized on the molecular level. The pMMO active site is believed to reside in the soluble N-terminal region of the pmoB subunit. To understand the degree of structural conservation within this superfamily, the crystal structure of the corresponding domain of an archaeal amoB subunit from Nitrosocaldus yellowstonii has been determined to 1.8 A resolution. The structure reveals a remarkable conservation of overall fold and copper binding site location as well as several notable differences that may have implications for function and stability.

N-methyl mesoporphyrin IX (NMM) is exceptionally selective for G-quadruplexes (GQ) relative to duplex DNA and, as such, has found a wide range of applications in biology and chemistry. In addition, NMM is selective for parallel versus antiparallel GQ folds, as was recently demonstrated in our laboratory. Here, we present the X-ray crystal structure of a complex between NMM and human telomeric DNA dAGGG(TTAGGG)(3), Tel22, determined in two space groups, P2(1)2(1)2 and P6, at 1.65 and 2.15 Å resolution, respectively. The former is the highest resolution structure of the human telomeric GQ DNA reported to date. The biological unit contains a Tel22 dimer of 5'-5' stacked parallel-stranded quadruplexes capped on both ends with NMM, supporting the spectroscopically determined 1:1 stoichiometry. NMM is capable of adjusting its macrocycle geometry to closely match that of the terminal G-tetrad required for efficient π-π stacking. The out-of-plane N-methyl group of NMM fits perfectly into the center of the parallel GQ core where it aligns with potassium ions. In contrast, the interaction of the N-methyl group with duplex DNA or antiparallel GQ would lead to steric clashes that prevent NMM from binding to these structures, thus explaining its unique selectivity. On the basis of the biochemical data, binding of NMM to Tel22 does not rely on relatively nonspecific electrostatic interactions, which characterize most canonical GQ ligands, but rather it is hydrophobic in nature. The structural features observed in the NMM-Tel22 complex described here will serve as guidelines for developing new quadruplex ligands that have excellent affinity and precisely defined selectivity.

Biological conversion of natural gas to liquids (Bio-GTL) represents an immense economic opportunity. In nature, aerobic methanotrophic bacteria and anaerobic archaea are able to selectively oxidize methane using methane monooxygenase (MMO) and methyl coenzyme M reductase (MCR) enzymes. Although significant progress has been made toward genetically manipulating these organisms for biotechnological applications, the enzymes themselves are slow, complex, and not recombinantly tractable in traditional industrial hosts. With turnover numbers of 0.16-13 s(-1), these enzymes pose a considerable upstream problem in the biological production of fuels or chemicals from methane. Methane oxidation enzymes will need to be engineered to be faster to enable high volumetric productivities; however, efforts to do so and to engineer simpler enzymes have been minimally successful. Moreover, known methane-oxidizing enzymes have different expression levels, carbon and energy efficiencies, require auxiliary systems for biosynthesis and function, and vary considerably in terms of complexity and reductant requirements. The pros and cons of using each methane-oxidizing enzyme for Bio-GTL are considered in detail. The future for these enzymes is bright, but a renewed focus on studying them will be critical to the successful development of biological processes that utilize methane as a feedstock.

The CopC proteins are periplasmic copper binding proteins believed to play a role in bacterial copper homeostasis. Previous studies have focused on CopCs that are part of seven-protein Cop or Pco systems involved in copper resistance. These canonical CopCs contain distinct Cu(I) and Cu(II) binding sites. Mounting evidence suggests that CopCs are more widely distributed, often present only with the CopD inner membrane protein, frequently as a fusion protein, and that the CopC and CopD proteins together function in the uptake of copper to the cytoplasm. In the methanotroph Methylosinus trichosporium OB3b, genes encoding a CopCD pair are located adjacent to the particulate methane monooxygenase (pMMO) operon. The CopC from this organism (Mst-CopC) was expressed, purified, and structurally characterized. The 1.46 Å resolution crystal structure of Mst-CopC reveals a single Cu(II) binding site with coordination somewhat different from that in canonical CopCs, and the absence of a Cu(I) binding site. Extensive bioinformatic analyses indicate that the majority of CopCs in fact contain only a Cu(II) site, with just 10% of sequences corresponding to the canonical two-site CopC. Accordingly, a new classification scheme for CopCs was developed, and detailed analyses of the sequences and their genomic neighborhoods reveal new proteins potentially involved in copper homeostasis, providing a framework for expanded models of CopCD function.

OBJECTIVE. This article focuses on four high-risk lesions: lobular neoplasia, benign papilloma, radial scar, and flat epithelial atypia. Controversies exist in the management after core biopsy of each of these lesions—whether to perform immediate surgical excision so as not to miss an associated malignancy or imaging follow-up because concomitant malignancy is low. This review is staged in two parts per lesion. The first is from data gathered during the last two American Roentgen Ray Society annual meetings from the audience response system querying practice management styles per diagnostic lesion. The second part is a brief review of selected articles recommending either follow-up or surgery. The strengths and weaknesses of each article are discussed. CONCLUSION. Our opinion is that neither recommendation, surgical excision or fol- low-up, is well substantiated in the literature and that our ignorance is not serving the needs of women worldwide. The time is now for a prospective trial.

Purpose. The Oncotype DX assay predicts likelihood of distant recurrence and improves patient selection for adjuvant chemotherapy in estrogen receptor–positive (ER-positive) early stage breast cancer. This study has two primary endpoints: to evaluate the impact of Oncotype DX recurrence scores (RS) on chemotherapy recommendations and to compare the estimated recurrence risk predicted by breast oncology specialists to RS. Methods. One hundred fifty-four patients with ER-positive early stage breast cancer and available RS results were selected. Clinicopathologic data were provided to four surgeons, four medical oncologists, and four pathologists. Participants were asked to estimate recurrence risk category and offer their chemotherapy recommendations initially without and later with knowledge of RS results. The three most important clinicopathologic features guiding their recommendations were requested. Results. Ninety-five (61.7%), 45 (29.2%), and 14 (9.1%) tumors were low, intermediate, and high risk by RS, respectively. RS significantly correlated with tumor grade, mitotic activity, lymphovascular invasion, hormone receptor, and HER2/neu status. Estimated recurrence risk by participants agreed with RS in 54.2% ± 2.3% of cases. Without and with knowledge of RS, 82.3% ± 1.3% and 69.0% ± 6.9% of patients may be overtreated, respectively (p = 0.0322). Inclusion of RS data resulted in a 24.9% change in treatment recommendations. There was no significant difference in recommendations between groups of participants. Conclusions. Breast oncology specialists tended to overestimate the risk of tumor recurrence compared with RS. RS provides useful information that improves patient selection for chemotherapy and changes treatment recommendations in approximately 25% of cases.

Purpose: To determine, by molecular imaging, how in vivo pharmacodynamics of estrogen-estrogen receptor (ER) binding differ between types of standard endocrine therapy. Experimental Design: The ER has been a highly successful target for breast cancer treatment. ER-directed treatments include lowering ligand concentration by using aromatase inhibitors (AI) and blocking the receptor with agents like tamoxifen (TAM) or fulvestrant (FUL). We measured regional estrogen-ER binding by using positron emission tomography with 18F-fluoroestradiol (FES PET) prior to and during treatment with AI, TAM, or FUL in a series of 30 metastatic breast cancer patients. FES PET measured in vivo estrogen binding at all tumor sites in heavily pretreated women with metastatic bone soft tissue–dominant breast cancer. In patients with uterus (n = 16) changes in uterine FES uptake were also measured. Results: As expected, tumor FES uptake declined more markedly on ER blockers (TAM and FUL, average 54% decline) compared with a less than 15% average decline on estrogen-depleting AIs (P < 0.001). The rate of complete tumor blockade [FES standardized uptake value (SUV) ≤1.5] following TAM (5/5 patients) was greater than the blockade rate following FUL (4/11; 2-sided mid P = 0.019). Percent FES SUV change in the uterus showed a strong association with tumoral change (ρ = 0.63, P = 0.01). Conclusions: FES PET can assess the in vivo pharmacodynamics of ER-targeted agents and may give insight into the activity of established therapeutic agents. Imaging revealed significant differences between agents, including differences in the efficacy of blockade by different ER antagonists in current clinical use. Clin Cancer Res; 17(14); 4799–805. ©2011 AACR.

Readers may feel less than satisfied when they discover that there is no consensus on the appropriate recommendations for follow-up of risk lesions following percutaneous core biopsy. The significance of this article is in the details of the methodologies and results, and much less in the numbers. The overall goal is to emphasize the flaws in current studies.

Ammonia-oxidizing archaea are ubiquitous in marine and terrestrial environments and now thought to be significant contributors to carbon and nitrogen cycling. The isolation of Candidatus “ Nitrosopumilus maritimus ” strain SCM1 provided the opportunity for linking its chemolithotrophic physiology with a genomic inventory of the globally distributed archaea. Here we report the 1,645,259-bp closed genome of strain SCM1, revealing highly copper-dependent systems for ammonia oxidation and electron transport that are distinctly different from known ammonia-oxidizing bacteria. Consistent with in situ isotopic studies of marine archaea, the genome sequence indicates N. maritimus grows autotrophically using a variant of the 3-hydroxypropionate/4-hydroxybutryrate pathway for carbon assimilation, while maintaining limited capacity for assimilation of organic carbon. This unique instance of archaeal biosynthesis of the osmoprotectant ectoine and an unprecedented enrichment of multicopper oxidases, thioredoxin-like proteins, and transcriptional regulators points to an organism responsive to environmental cues and adapted to handling reactive copper and nitrogen species that likely derive from its distinctive biochemistry. The conservation of N. maritimus gene content and organization within marine metagenomes indicates that the unique physiology of these specialized oligophiles may play a significant role in the biogeochemical cycles of carbon and nitrogen.

The two-domain multicopper oxidases are proposed to be key intermediates in the evolution of three-domain multicopper oxidases. A number of two-domain multicopper oxidases have been identified from genome sequences and are classified as type A, type B, or type C on the basis of the predicted location of the type 1 copper center. The crystal structure of blue copper oxidase, a type C two-domain multicopper oxidase from Nitrosomonas europaea, has been determined to 1.9 A resolution. Blue copper oxidase is a trimer, of which each subunit comprises two cupredoxin domains. Each subunit houses a type 1 copper site in domain 1 and a type 2/type 3 trinuclear copper cluster at the subunit-subunit interface. The coordination geometry at the trinuclear copper site is consistent with reduction of the copper ions. Although the overall architecture of blue copper oxidase is similar to nitrite reductases, detailed structural alignments show that the fold and domain orientation more closely resemble the three-domain multicopper oxidases. These observations have important implications for the evolution of nitrite reductases and multicopper oxidases.

The PET compound (18)F-fluoroestradiol ((18)F-FES) has been developed and tested as an agent for the imaging of estrogen receptor (ER) expression in vivo. (18)F-FES uptake has been shown to correlate with ER expression assayed in vitro by radioligand binding; however, immunohistochemistry (IHC) rather than radioligand binding is used most often to measure ER expression in clinical practice. We therefore compared (18)F-FES uptake with ER expression assayed in vitro by IHC with both qualitative and semiquantitative measures.Seventeen patients with primary or metastatic breast cancer were studied with dynamic (18)F-FES PET; cancer tissue samples, collected close to the time of imaging, were assayed for ER expression by IHC. For each tumor, partial-volume-corrected measures of (18)F-FES uptake were compared with ER expression measured by 3 different ER scoring methods: qualitative scoring (0-3+), the Allred score (0-10), and a computerized IHC index.There was excellent agreement (r = 0.99) between observers using IHC as well as the different methods of measuring ER content (P0.001). ER-negative tumors had (18)F-FES partial-volume-corrected standardized uptake values of less than 1.0, whereas ER-positive tumors had values above 1.1. Correlation coefficients for the different measures of ER content and the different measures of (18)F-FES uptake ranged from 0.57 to 0.73, with the best correlation being between the computerized IHC index and (18)F-FES partial-volume-corrected standardized uptake values.Our results showed good agreement between (18)F-FES PET and ER expression measured by IHC. (18)F-FES imaging may be a useful tool for aiding in the assessment of ER status, especially in patients with multiple tumors or for tumors that are difficult to biopsy.

The seminal study in 2000 by Perou and colleagues1 describing the molecular classification of breast cancer based on complementary DNA microarray analysis has forever changed the way we view this disease. Their results supported the concept that breast cancer is not a single entity but rather a heterogeneous group of tumors with diverse behavior and corresponding gene expression patterns. Subsequently, the same group refined their molecular subtypes using a greater number of tumors and identified the now familiar five distinct gene expression patterns: luminal A, luminal B, HER2+, basal-like, and normal breast-like.2 They further demonstrated a correlation between tumor subtype and patient outcome, including overall survival and relapse-free survival. Since the publication of these studies, numerous other investigators have confirmed the clinical significance of this classification system,3–7 including the prognostic and predictive value of the molecular subtypes. Since immunohistochemistry (IHC) is a more accessible and inexpensive modality in the clinical setting, there has been ongoing interest in using protein expression to identify the subclasses. Based on the particular gene clusters differentially expressed among the subtypes and their correlation with protein expression, the most commonly used IHC stains have been estrogen receptor (ER), progesterone receptor (PR), HER2/neu, and Ki-67.1,3,4,6–9 IHC for CK5/6 and epidermal growth factor receptor (HER1) also has been used to further distinguish the basal-like subtype.6,8 In …

Rationale and objectives The purpose of the study was to evaluate the hypothesis that magnetic resonance imaging (MRI) and positron emission tomography (PET) are complementary and valuable in monitoring response and assessing residual disease of locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy. We sought to determine if the combination of the two modalities was more accurate than either alone and could provide better guidance in patient management. Materials and methods Sixteen lesions in 15 women with LABC were evaluated with MRI, PET, and clinical breast examination (CBE) before and after neoadjuvant chemotherapy. The pre- and posttherapy maximal tumor sizes on MRI and CBE and standard uptake values (SUVs) on PET served as the measurements for clinical response classification and residual disease assessment. Pathologic assessment provided the reference for macroscopic and microscopic pathologic tumor response and residual disease. Results PET correctly predicted lack of pathologic response in five of six cases (83%); CBE predicted correctly in one of six (17%) cases, and MRI predicted correctly in zero of six cases. When PET predicted response, MRI defined the extent of macroscopic pathologic residual disease accurately in 9 of 10 cases (90%). When posttherapy MRI showed complete response (CR) in eight cases, macroscopic pathologic complete response (mCR) was observed in all eight cases (100%). Conclusion Our study suggests that combined use of MRI and PET is complementary and offers advantages over CBE. PET was more accurate in predicting pathologic nonresponse. Complete response by MRI correlated well with macroscopic pathologic complete response.

Evaluation of papillary lesions of the breast can be difficult, and in core needle biopsy specimens, accurate diagnosis is challenging. Initial studies suggested that all papillary lesions revealed by core biopsy required surgical excision. Recent data suggest that only papillary lesions with atypical ductal hyperplasia (ADH) revealed by core biopsy need surgical excision. We evaluated our experience at the University of Washington Medical Center, Seattle, with papillary lesions with and without ADH on core biopsy to determine whether diagnostic accuracy can be achieved. In 51 core biopsy specimens, we evaluated the presence or absence of ADH: 25 were benign papillomas; 26 were papillomas with ADH. Surgical follow-up was available for 36 cases (11 papillomas and 25 papillomas with ADH). Clinical (radiologic) follow-up was available in 5 papilloma cases (average follow-up, 35.6 months). Follow-up revealed that all papillomas on core biopsy were benign. Excisional biopsy revealed ductal carcinoma in situ or invasive carcinoma in 12 (48%) of 25 papillary lesions with ADH. Benign papillomas can be adequately diagnosed with core biopsy. All papillary lesions with ADH require surgical excision owing to the high rate of associated neoplasia.

About 500 to 600 million metric tons of methane, a potent greenhouse gas, are emitted annually worldwide; ~69% of this methane is produced biologically by anaerobic archaea known as methanogens ( 1 ). In some environments, methane emissions are partly offset by anaerobic methane oxidizing archaea (ANME) and aerobic methanotrophic bacteria ( 1 ). In methanogens, the methyl-coenzyme M reductase (MCR) enzyme uses a nickel-containing cofactor (F430) to catalyze the final step of methane synthesis (see the figure, panels A and B) ( 2 , 3 ). The MCR reaction is reversible, and MCR may also catalyze the first step of methane oxidation by ANME ( 2 ). The MCR catalytic cycle begins with F430 in the reduced Ni(I) form ( 4 ), but what happens next has been unclear. On page 953 of this issue, Wongnate et al. ( 5 ) report evidence for a Ni(II)-thiolate intermediate.

We sought to determine the prevalence of androgen receptor (AR) expression in a predominantly estrogen receptor (ER)-negative subset of breast cancers and delineate the immunohistochemical and clinical associations, including whether AR expression has prognostic significance in ER-negative tumors. We identified 69 ER-negative and 19 ER-positive breast cancer cases with concurrent immunohistochemical prognostic panels (ER, PR, HER-2/neu, Ki-67, and p53); immunohistochemical analysis was performed for AR using standard techniques. Clinical data were extracted from medical records. χ2 tests were used to assess associations between variables. AR was found in 49% (34/69) of ER-negative and 89% (17/19) of ER-positive cases. In ER-negative tumors, AR was associated with increased age ( P = .02), postmenopausal status ( P < .001), tumor grade ( P = .03), tumor size ( P = .03), and HER-2/neu overexpression ( P = .003). In ER-positive tumors, AR was associated with progesterone receptor expression ( P < .03). In univariate analysis of ER-negative tumors, patients with AR-positive tumors had significantly better disease-free survival ( P = .049). AR is expressed in a significant number of ER-negative cases and shows significant associations with important clinical and pathologic prognostic factors.

Lobular carcinoma in situ (LCIS) is a preinvasive breast lesion associated with a 6 to 11-fold increased risk of invasive breast cancer. Despite this increased risk, little is known regarding what qualities of LCIS predispose individual patients to invasive cancer. Given recent advances in understanding of the importance of etiologic heterogeneity within breast cancer, we sought to characterize morphologic markers of heterogeneity in LCIS and surrounding tissue, with the hypothesis that features with lesional variation may be important candidate predictors of breast cancer risk. We identified 64 patients aged ≥ 18 years who were diagnosed with LCIS at a single institution from 2004-2014. Patients with concurrent invasive breast cancer in the same breast were excluded. Archival slides of each case were reviewed by an experienced breast pathologist to confirm the presence of LCIS and characterize the LCIS type (classic, florid, or pleomorphic). The number of lobules involved with LCIS, presence of calcifications or necrosis associated with LCIS, and presence of other benign lesions [atypical lobular hyperplasia (ALH), atypical ductal hyperplasia (ADH), flat epithelial atypia, fibroadenoma, intraductal papilloma] were recorded. Age at surgery and surgery type were abstracted from medical records. The two-sided Fisher’s exact test was used to examine differences in proportions. The mean age of the cases was 53 years, and the most common surgery type was excisional/incisional biopsy or lumpectomy (55%), followed by core biopsy (25%) and mastectomy (20%). Calcifications were associated with LCIS in 41% of cases. Women were more likely to have florid LCIS when calcifications were present compared to when calcifications were absent (P0.05). ALH was the most common other lesion, present in 70% of samples.. Our results demonstrate that LCIS-associated calcifications are common and are associated with more extensive disease, even among LCIS characterized as ‘classic’. In invasive breast cancer, the presence of certain types of calcifications has been associated with poor prognosis. A next step in this research is to understand whether the heterogeneity we observed in LCIS can be ascribed to a specific calcification morphology and/or distribution. Understanding this will help us elucidate the potential biological mechanism and determine whether LCIS calcifications are a viable marker for the prediction of breast cancer risk. Citation Format: Sarah J. Nyante, Emily Ozdowski, Xianming Tan, Thomas J. Lawton. Tissue-based heterogeneity in lobular carcinoma in situ [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5308. doi:10.1158/1538-7445.AM2017-5308

Five female patients undergoing cyclosporin A therapy had newly developed breast masses. Masses were bilateral in three of the five patients and palpable in four patients. The imaging findings were suggestive of fibroadenomas, and biopsy results were used to confirm the diagnosis. With the development of new breast lesions in patients after transplantation surgery, the diagnosis of cyclosporin A-induced fibroadenomas should be considered.

Background: Some patients undergoing axillary lymph node dissection (ALND) experience postoperative pain and limited range of motion associated with a palpable web of tissue extending from the axilla into the ipsilateral arm. The purpose of this study is to characterize the previously undescribed axillary web syndrome (AWS). Methods: To identify patients with AWS, a retrospective review was performed of all invasive breast cancer patients treated by a single surgeon (REM) between 1980 and 1996. Records were also reviewed of 4 more recent patients who developed AWS after undergoing sentinel node lymph node dissection (SLND) without ALND. Results: Among 750 sequentially treated patients, 44 (6%) developed AWS between 1 and 8 weeks after their axillary procedure. The palpable subcutaneous cords extended from the axillary crease down the ipsilateral arm, across the antecubital space, and in severe cases down to the base of the thumb. The web was associated with pain and limited shoulder abduction (≤90° in 74% of patients). AWS resolved in all cases within 2 to 3 months. AWS also occurred after SLND. Tissue sampling of webs in 4 patients showed occlusion in lymphatic and venous channels. Conclusions: AWS is a self-limiting cause of morbidity in the early postoperative period. More limited axillary surgery, with less lymphovenous disruption, might reduce the severity and incidence of this syndrome, although SLND does not eliminate its occurrence.

We report the first case of an Echinococcal cyst and focal nodular hyperplasia, two usually isolated hepatic lesions, in direct contiguity. The patient presented with right upper quadrant pain and subsequent imaging studies found a cystic and solid lesion. These studies suggested that this lesion was an hepatic adenoma, which had bled forming a hematoma. Pathological examination of the surgical resection showed Echinococcus multilocularis with contiguous focal nodular hyperplasia. Because focal nodular hyperplasia is a benign hepatic lesion the etiology of which is thought to be abnormal arterial blood flow, we postulate that the parasitic hepatic infection by E. multilocularis may have incited the formation of this contiguous hepatic lesion.

Recent studies suggest that altered expression of intercellular adhesion molecules (ICAM) in ductal carcinoma of the breast is associated with a higher incidence of metastases and decreased patient survival. In addition, the presence of significant cellular dyscohesion in cytologic smear preparations has been found to correlate with the presence of regional and distant metastases in a subset of patients. In this study, we correlate the smear pattern in preparations taken directly from surgically excised breast tumors with their immunohistochemical staining pattern, using antibodies directed against a panel of ICAM. We found excellent correlation, as all three tumors with an extremely high degree of tumor cell cohesion showed strong staining with all ICAM antibodies in the vast majority (>/=90%) of tumor cells in corresponding tissue sections. In contrast, five tumors displaying a largely dyscohesive smear pattern demonstrated decreased staining (

We describe four cases of solitary parathyroid adenomas with prominent lymphocytic infiltrates presenting as primary hyperparathyroidism. There was no involvement of the other parathyroid glands in the three cases in which they were biopsied. In two cases the thyroids were removed and were without lymphoid infiltrates. The infiltrates were composed of a mixed population of B and T lymphocytes in the three cases that had material available for immunohistochemistry. There was no evidence of parathyroid parenchymal destruction, and in none of the patients was an autoimmune disease present clinically or serologically. We hypothesize that lymphocytic infiltrates in parathyroid adenomas are an uncommon, but clinically innocuous, histologic finding and their presence does not imply an autoimmune disorder.

Nitrifier denitrification is the conversion of nitrite to nitrous oxide by ammonia-oxidizing organisms. This process, which is distinct from denitrification, is active under aerobic conditions in the model nitrifier Nitrosomonas europaea. The central enzyme of the nitrifier dentrification pathway is a copper nitrite reductase (CuNIR). To understand how a CuNIR, typically inactivated by oxygen, functions in this pathway, the enzyme isolated directly from N. europaea (NeNIR) was biochemically and structurally characterized. NeNIR reduces nitrite at a similar rate to other CuNIRs but appears to be oxygen tolerant. Crystal structures of oxidized and reduced NeNIR reveal a substrate channel to the active site that is much more restricted than channels in typical CuNIRs. In addition, there is a second fully hydrated channel leading to the active site that likely acts a water exit pathway. The structure is minimally affected by changes in pH. Taken together, these findings provide insight into the molecular basis for NeNIR oxygen tolerance.

There are several pathologic lesions in the female breast that are so-called “high risk” because of epidemiologic data suggesting that a diagnosis of one of these lesions on a biopsy increases a woman’s risk of developing a subsequent carcinoma. Among the most common of these lesions are lobular neoplasia (atypical lobular hyperplasia and lobular carcinoma in situ), columnar cell lesions (including flat epithelial atypia), atypical ductal hyperplasia, papillary lesions, and radial scar/complex sclerosing lesions. In this chapter, the specific histopathologic diagnostic criteria for each of these lesions will be discussed and associated images of each will be displayed.

Purpose Some postmenopausal patients with hormone-sensitive early breast cancer remain at high risk of relapse despite endocrine therapy and, in addition, might benefit from adjuvant chemotherapy. The challenge is to prospectively identify such patients. The Mammostrat test uses five immunohistochemical markers to stratify patients regarding recurrence risk and may inform treatment decisions. We tested the efficacy of this panel in the Tamoxifen versus Exemestane Adjuvant Multicenter (TEAM) trial. Patients and Methods Pathology blocks from 4,598 TEAM patients were collected, and tissue microarrays (TMAs) were constructed. The cohort was 47% node-positive, and 36% of patients in the cohort were treated with adjuvant chemotherapy. Triplicate 0.6-mm2 TMA cores were stained, and positivity for p53, HTF9C, CEACAM5, NDRG1, and SLC7A5 was assessed. Cases were assigned a Mammostrat risk score, and distant relapse-free survival (DRFS) and disease-free survival (DFS) were analyzed. Results In multivariate regression analyses, which were corrected for conventional clinicopathologic markers, Mammostrat provided significant additional information on DRFS after endocrine therapy in estrogen receptor (ER) –positive node-negative patients (n = 1,226) who did not receive chemotherapy (P = .004). Additional analyses in all patients not exposed to chemotherapy, irrespective of nodal status (n = 2,559) and in the entire cohort (n = 3,837) showed Mammostrat scores provided additional information on DRFS in these groups (P = .001 and P < .001, respectively; multivariate analyses). No differences were seen between the two endocrine treatment regimens. Conclusion The Mammostrat score predicts DRFS for patients treated with exemestane and patients treated with tamoxifen followed by exemestane irrespective of nodal status and chemotherapy. The ability of this test to provide additional outcome data after treatment provides additional evidence of its use in risk stratification of ER-positive postmenopausal patients with breast cancer.

Blue copper oxidase (BCO) is a multicopper oxidase (MCO) found in Nitrosomonas europaea as well as in other ammonia-oxidizing organisms. In this chapter, we detail methods used to detect, isolate, and characterize BCO from N. europaea. A method for identifying and classifying MCOs commonly found in nitrifiers based on primary sequence is also described.

Blue copper oxidase (BCO) is a multicopper oxidase (MCO) found in Nitrosomonas europaea as well as in other ammonia-oxidizing organisms. In this chapter, we detail methods used to detect, isolate, and characterize BCO from N. europaea. A method for identifying and classifying MCOs commonly found in nitrifiers based on primary sequence is also described.

Background. Globally mobile populations are at higher risk of acquiring geographically restricted infections and may play a role in the international spread of infectious diseases. Despite this, data about sources of health information used by international travelers are limited. Methods. We surveyed 1,254 travelers embarking from Boston Logan International Airport regarding sources of health information. We focused our analysis on travelers to low or low-middle income (LLMI) countries, as defined by the World Bank 2009 World Development Report. Results. A total of 476 survey respondents were traveling to LLMI countries. Compared with travelers to upper-middle or high income (UMHI) countries, travelers to LLMI countries were younger, more likely to be foreign-born, and more frequently reported visiting family as the purpose of their trip. Prior to their trips, 46% of these travelers did not pursue health information of any type. In a multivariate analysis, being foreign-born, traveling alone, traveling for less than 14 days, and traveling for vacation each predicted a higher odds of not pursuing health information among travelers to LLMI countries. The most commonly cited reason for not pursuing health information was a lack of concern about health problems related to the trip. Among travelers to LLMI countries who did pursue health information, the internet was the most common source, followed by primary care practitioners. Less than a third of travelers to LLMI countries who sought health information visited a travel medicine specialist. Conclusions. In our study, 46% of travelers to LLMI countries did not seek health advice prior to their trip, largely due to a lack of concern about health issues related to travel. Among travelers who sought medical advice, the internet and primary care providers were the most common sources of information. These results suggest the need for health outreach and education programs targeted at travelers and primary care practitioners.

Two-domain multicopper oxidases (2dMCOs) couple the four-electron reduction of dioxygen to the oxidation of a number of different substrates, including organic compounds and reduced ferricytochromes. The geometry of 2dMCO active sites is similar to that in other multicopper oxidases, but is formed by a significantly different protein architecture. This fold resembles the overall architecture of NO forming copper nitrite reductase (CuNIR). 2dMCOs are classified based on the location of their type-1 copper centers. 3D Structure Keywords: multicopper; two-domain; oxidase; oxygen; blue; trinuclear; nitrite reductase

Purpose Patients with locally advanced breast carcinoma (LABC) receive preoperative chemotherapy to provide early systemic treatment and assess in vivo tumor response. Serial positron emission tomography (PET) has been shown to predict pathologic response in this setting. We evaluated serial quantitative PET tumor blood flow (BF) and metabolism as in vivo measurements to predict patient outcome. Patients and Methods Fifty-three women with primary LABC underwent dynamic [18F]fluorodeoxyglucose (FDG) and [15O]water PET scans before and at midpoint of neoadjuvant chemotherapy. The FDG metabolic rate (MRFDG) and transport (FDG K1) parameters were calculated; BF was estimated from the [15O]water study. Associations between BF, MRFDG, FDG K1, and standardized uptake value and disease-free survival (DFS) and overall survival (OS) were evaluated using the Cox proportional hazards model. Results Patients with persistent or elevated BF and FDG K1 from baseline to midtherapy had higher recurrence and mortality risks than patients with reductions. In multivariable analyses, BF and FDG K1 changes remained independent prognosticators of DFS and OS. For example, in the association between BF and mortality, a patient with a 5% increase in tumor BF had a 67% higher mortality risk compared with a patient with a 5% decrease in tumor BF (hazard ratio = 1.67; 95% CI, 1.24 to 2.24; P < .001). Conclusion LABC patients with limited or no decline in BF and FDG K1 experienced higher recurrence and mortality risks that were greater than the effects of clinical tumor characteristics. Tumor perfusion changes over the course of neoadjuvant chemotherapy measured directly by [15O]water or indirectly by dynamic FDG predict DFS and OS.

Combined estrogen and progestin hormone therapy (CHT) increases breast cancer risk, but this risk varies by breast cancer type. Several studies indicate that CHT is more strongly related to lobular carcinoma risk than to ductal carcinoma risk, but these studies have been limited in their assessments of recency and duration of use, and none included a centralized pathology review. We conducted a population-based case-control study consisting of 324 lobular, 196 ductal-lobular, and 524 ductal cases diagnosed from 2000 to 2004 and 469 controls ages 55 to 74 years old. Tissue specimens were centrally reviewed for 83% of cases. Associations between hormone use and breast cancer risk were evaluated using polytomous logistic regression. Current CHT users had 2.7-fold [95% confidence interval (95% CI), 1.7-4.2] and 3.3-fold (95% CI, 2.0-5.7) elevated risks of lobular and ductal-lobular carcinomas, respectively, regardless of tumor stage, size, or nodal status. Elevations in risk were observed only among users of CHT for ≥3 years. Among ductal-lobular cases, CHT increased risk of tumors that were ≥50% lobular (odds ratio, 4.8; 95% CI, 2.1-11.1) but not tumors that were

BACKGROUND Studies utilizing serial [99mTc]-sestamibi (MIBI) scintimammography have reported accurate prediction of tumor response in patients with locally advanced breast carcinoma (LABC) undergoing neoadjuvant chemotherapy. The pathologic response of LABC to presurgical treatment regimens is a prognostic indicator of survival. The authors tested whether MIBI uptake posttherapy predicted survival. METHODS Sixty-two patients with LABC underwent MIBI scintimammography just before chemotherapy and 2 months after treatment initiation. An additional MIBI scan was performed if treatment lasted > 3 months. The affected breast was imaged within 10 minutes after injection to reflect early uptake, which the authors have shown to be related to tumor blood flow. MIBI uptake was quantified using the lesion-to-normal breast (L:N) ratio. Most patients (93%) received weekly dose-intensive doxorubicin-based treatment. Disease-free survival (DFS) and overall survival (OS) were compared with posttherapy primary MIBI uptake and with other established prognostic factors for neoadjuvantly treated LABC, namely, primary tumor pathologic response and posttherapy axillary lymph node status. RESULTS Patients with high uptake on the last observed MIBI scan (i.e., the L:N ratio was greater than the median value) had poorer DFS and OS (P < 0.01 and P = 0.01, respectively). Residual MIBI uptake retained independent prognostic significance in preliminary multivariate analysis that included other established prognostic markers. CONCLUSIONS High primary breast tumor MIBI uptake after neoadjuvant chemotherapy predicted poor survival, suggesting serial MIBI imaging may provide a useful quantitative surrogate end point for neoadjuvant chemotherapy trials. Given the association between MIBI uptake and tumor blood flow, this prognostic capability may be related to retained tumor vascularity after treatment. Cancer 2005. © 2005 American Cancer Society.

Evaluation of papillary lesions of the breast can be difficult, and in core needle biopsy specimens, accurate diagnosis is challenging. Initial studies suggested that all papillary lesions revealed by core biopsy required surgical excision. Recent data suggest that only papillary lesions with atypical ductal hyperplasia (ADH) revealed by core biopsy need surgical excision. We evaluated our experience at the University of Washington Medical Center, Seattle, with papillary lesions with and without ADH on core biopsy to determine whether diagnostic accuracy can be achieved. In 51 core biopsy specimens, we evaluated the presence or absence of ADH: 25 were benign papillomas; 26 were papillomas with ADH. Surgical follow-up was available for 36 cases (11 papillomas and 25 papillomas with ADH). Clinical (radiologic) follow-up was available in 5 papilloma cases (average follow-up, 35.6 months). Follow-up revealed that all papillomas on core biopsy were benign. Excisional biopsy revealed ductal carcinoma in situ or invasive carcinoma in 12 (48%) of 25 papillary lesions with ADH. Benign papillomas can be adequately diagnosed with core biopsy. All papillary lesions with ADH require surgical excision owing to the high rate of associated neoplasia.