Trans-radial cerebral angiography for stereotactic radiosurgery treatment of arteriovenous malformations.

OBJECTIVES: The popularity of trans-radial access (TRA) for cerebral angiography is growing. Potential benefits of TRA over traditional trans-femoral access (TFA) are multitude. This study aimed to evaluate discharge outcomes and patient opinion of TRA compared to TFA in patients undergoing cerebral angiography prior to stereotactic radiosurgery (SRS) treatment for cerebral arteriovenous malformations. METHODS: Consecutive patients treated at the National Centre for Stereotactic Radiosurgery (Sheffield, United Kingdom) over a 22-month period were included. All patients underwent cerebral angiography with either TRA or TFA as part of treatment planning prior to SRS. TRA patients who had previously undergone TFA in other centres were surveyed for their experience of cerebral angiography using a questionnaire. SRS staff at our centre was approached for their opinion. RESULTS: 492 patients were included (median age = 43 years, 57.5% male, median lesions treated = 1). More patients underwent angiography with TFA (75.2%) than TRA (24.8%). No difference was found in accumulated dose for angiography between the groups (p>0.05). There was 17.6% reduction in overnight stay between TRA and TRF, the proportion of patients requiring overnight admission was higher for the TFA (35.2%) than TRA (17.6%, p<0.05). 101 patients were surveyed, with a response rate of 47%. Most respondents (79%) indicated preference for TRA over TFA. CONCLUSIONS: Use of TRA in pre-SRS cerebral angiography is feasible and improves both patient and staff experience. The adoption of TRA could have important implications for department resources and costs by reducing the proportion of overnight admissions.

Echocardiography update for primary care physicians: a review.

Echocardiography is a key evaluation tool for the diagnosis, prognosis, and guidance of interventional management of numerous cardiovascular conditions, including ischaemia, heart failure, and structural heart diseases. Recent technological advancements have also seen the exploration of artificial intelligence, intracardiac vortex imaging, and three-dimensional printing in echocardiography. With cardiovascular diseases increasing in prevalence worldwide, it is important for clinicians including general practitioners to have updated knowledge of appropriate use of echocardiography. As such, this article reviews the current literature and summarises the latest developments and the general clinical usage of echocardiography.

Intracardiac echocardiography for percutaneous patent foramen ovale and atrial septal defect occlusion.

BACKGROUND: Transesophageal echocardiography (TEE) plays a unique role in transcatheter closure of atrial septal defects (ASD) and patent foramen ovale (PFO). However, problems such as the need for general anesthesia, possible trauma from endotracheal intubation, presence of "blind spots," and occasional inadequate imaging of some cardiac structures have necessitated better imaging techniques. Our study aimed to compare the findings of TEE during the initial diagnostic examination with those from intracardiac echocardiography (ICE) acquired during the interventional procedure. METHODS: A total of 65 patients in whom TEE was used for the diagnosis of ASD or PFO were included. Of these, 40 patients (61.5%) had ASD with significant left to right shunt and 25 (38.5%) patients had PFO associated with transient ischemic attack or stroke. ICE imaging was performed under local anesthesia in all patients to guide interatrial communication closure. RESULTS: ICE provided adequate views of the defects and surrounding structures during the various stages of device deployment. In eight patients (12.3%) an additional anatomical variation was detected. All patients had successful device implantation and were discharged 1 day after the procedure. CONCLUSION: ICE is a safe and high-quality imaging technique for guiding transcatheter ASD and PFO occlusion. Additionally, ICE can both facilitate device implantation and detect cardiac abnormalities that are not identified with TEE during the initial diagnostic investigation.

Oncogenes expand during evolution to withstand somatic amplification.

Background: Cancer-related genes are under intense evolutionary pressure. We conjectured that gene size is an important determinant of amplification propensity for oncogenes and thus cancer susceptibility and therefore could be subject to natural selection. Patients and methods: Gene information, including size and genomic locations, of all protein-coding genes were downloaded from Ensembl (release 87). Quantification of gene amplification was based on Genomic Identification of Significant Targets in Cancer scores obtained from available The Cancer Genome Atlas studies. Results: Oncogenes are larger in size as compared with non-cancer genes (mean size: 92.1 kb versus 61.4 kb; P < 0.0001) in the human genome, which is contributed by both increased total exon size (mean size: 4.6 kb versus 3.4 kb; P < 0.0001) and higher intronic content (mean %: 84.8 versus 78.0; P < 0.01). Such non-random size distribution and intronic composition are conserved in mouse and Drosophila (all P < 0.0001). Stratification by gene age indicated that young oncogenes have been subject to a stronger evolutionary pressure for gene expansion than their non-cancer counterparts. Pan-cancer analysis demonstrated that larger oncogenes were amplified to a lesser extent. Tumor-suppressor genes also moved toward small oncogenes in the course of evolution. Conclusions: Oncogenes expand in size whereas tumor-suppressor genes move closer to small oncogenes in the course of evolution to withstand oncogenic somatic amplification. Our findings have shed new light on the previously unappreciated influence of gene size on oncogene amplification and elucidated how cancers have shaped our genome to its present configuration.

Prognostic factors in metaplastic carcinoma of the breast: a multi-institutional study.

BACKGROUND: Metaplastic breast carcinoma (MBC) is a rare type of breast cancer that has basal-like characteristics and is perceived to have poorer prognosis when compared with conventional no specific type/ductal carcinomas (ductal/NST). However, current data on MBC are largely derived from small case series or population-based reports. This study aimed to assess the clinicopathological features and outcome of MBC identified through an international multicentre collaboration. METHODS: A large international multicentre series of MBC (no=405) with histological confirmation and follow-up information has been included in this study. The prognostic value of different variables and outcome has been assessed and compared with grade, nodal status and ER/HER2 receptor-matched ductal/NST breast carcinoma. RESULTS: The outcome of MBC diagnosed in Asian countries was more favourable than those in Western countries. The outcome of MBC is not different from matched ductal/NST carcinoma but the performance of the established prognostic variables in MBC is different. Lymph node stage, lymphovascular invasion and histologic subtype are associated with outcome but tumour size and grade are not. Chemotherapy was associated with longer survival, although this effect was limited to early-stage disease. In this study no association between radiotherapy and outcome was identified. Multivariate analysis of MBC shows that histologic subtype is an independent prognostic feature. CONCLUSIONS: This study suggests that MBC is a heterogeneous disease. Although the outcome of MBC is not different to matched conventional ductal/NST breast carcinoma, its behaviour is dependent on the particular subtype with spindle cell carcinoma in particular has an aggressive biological behaviour. Management of patients with MBC should be based on validated prognostic variables.

Intrarenal B Cell Cytokines Promote Transplant Fibrosis and Tubular Atrophy.

Renal transplantation is the optimum treatment for end-stage renal failure. B cells have been identified in chronic allograft damage (CAD) and associated with the development of tertiary lymphoid tissue within the human renal allograft. We performed renal transplantation in mice to model CAD and identified B cells forming tertiary lymphoid tissue with germinal centers. Intra-allograft B220(+) B cells comprised of IgM(high) CD23(-) B cells, IgM(lo) CD23(+) B cells, and IgM(lo) CD23(-) B cells with elevated expression of CD86. Depletion of B cells with anti-CD20 was associated with an improvement in CAD but only when administered after transplantation and not before. Isolated intra-allograft B cells were cultured and shown to synthesize multiple cytokines, the most abundant of these were GRO-α (CXCL1), RANTES (CCL5), IL-6 and MCP-1 (CCL2). Tubular loss was observed with T cell accumulation within the allograft and development of interstitial fibrosis, whilst type III collagen deposition was observed in areas of F4/80(+) macrophages and PDGFR-ß(+) and transgelin(+) fibroblasts, all of which were reduced by B cell depletion. We have shown that intra-allograft B cells are key mediators of CAD. B cells possibly contribute to CAD by intra-allograft secretion of cytokines and chemokines.

Graft arterial stenosis in kidney en bloc grafts from very small pediatric donors: incidence, timing, and role of ultrasound in screening.

In previous studies with different donor selection criteria and noncontemporary surgical techniques, graft arterial stenosis (GAS) has been reported to occur more frequently in adult recipients of pediatric en bloc renal allografts (EBKT) as compared to single adult donor allografts. The purpose of our study was to evaluate the incidence of GAS within our EBKT recipient population and to evaluate clinical and imaging features of those cases with GAS. In a retrospective cohort study, we analyzed 182 EBKT performed at a single institution. We identified cases of suspected GAS based on clinical factors, lab results, and noninvasive imaging. Diagnosis of GAS was confirmed by digital subtraction angiography. Two EBKT recipients (1.1% of 182) had angiographically confirmed GAS at 2.5 and 4.5 months after transplant. In both cases, the stenoses were short segment within the proximal (perianastomotic) donor aorta, color Doppler ultrasound demonstrated peak systolic velocities of >400 cm/s, and poststenotic parvus tardus waveforms were present. Both patients underwent angioplasty and demonstrated postintervention improvement in renal function and blood pressure. Restenosis did not occur during follow up. In conclusion, recipients of EBKT have a low incidence of GAS, similar to the lowest reported for adult single allografts.

Subtyping of triple-negative breast cancers: its prognostication and implications in diagnosis of breast origin.

BACKGROUND: Triple-negative breast cancer (TNBC) subtyping by gene profiling has provided valuable clinical information. Here, we aimed to evaluate the relevance of TNBC subtyping using immunohistochemistry (IHC), which could be a more clinically practical approach, for prognostication and applications in patient management. METHODS: A total of 123 TNBC cases were classified using androgen receptor (AR), CD8, Forkhead box C1 protein (FOXC1), and doublecortin-like kinase 1 (DCLK1) into luminal androgen receptor (LAR), basal-like immunosuppressive (BLIS), mesenchymal-like (MES), and immunomodulatory (IM) subtypes. The IM cases were further divided into the IM-excluded and IM-inflamed categories by CD8 spatial distribution. Their clinicopathological and biomarker profiles and prognoses were evaluated. RESULTS: LAR (28.6%) and MES (11.2%) were the most and least frequent subtypes. The IHC-TNBC subtypes demonstrated distinct clinicopathological features and biomarker profiles, corresponding to the reported features in gene profiling studies. IM-inflamed subtype had the best outcome, while BLIS had a significantly poorer survival. Differential breast-specific marker expressions were found. Trichorhinophalangeal syndrome type 1 (TRPS1) was more sensitive for IM-inflamed and BLIS, GATA-binding protein 3 (GATA3) for IM-excluded and MES, and gross cystic disease fluid protein 15 (GCDFP15) for LAR subtypes. CONCLUSIONS: Our findings demonstrated the feasibility of IHC surrogates to stratify TNBC subtypes with distinct features and prognoses. The IM subtype can be refined by its CD8 spatial pattern. Breast-specific marker expression varied among the subtypes. Marker selection should be tailored accordingly.

Long-term Cardiovascular Risks of Gonadotropin-releasing Hormone Agonists and Antagonists: A Population-based Cohort Study.

AIMS: Gonadotropin-releasing hormone (GnRH) agonists and antagonists, critical medications for prostate cancer (PCa) treatment, may differ in cardiovascular safety. This prospective cohort study aimed to compare the long-term cardiovascular risks between GnRH agonists and antagonists. MATERIALS AND METHODS: Patients with PCa receiving GnRH agonists or antagonists during 2013-2021 in Hong Kong were identified. Patients with <6 months' prescriptions, who were switching between drugs, had missing baseline prostate-specific antigen level or had a prior stroke or myocardial infarction were excluded. Patients were followed up until September 2021. The primary outcome was major adverse cardiovascular events (MACE) as in the PRONOUNCE trial (MACEPRONOUNCE), i.e. a composite of all-cause mortality, stroke and myocardial infarction. The secondary outcome was MACECVM, i.e. a composite of cardiovascular mortality, stroke and myocardial infarction. Inverse probability treatment weighting was used to balance covariates between groups. The Log-rank test was used to compare the cumulative freedom from the primary outcome between groups. RESULTS: In total, 2479 patients were analysed (162 GnRH antagonist users and 2317 agonist users; median age 75.0 years, interquartile range 68.0-81.6 years). Inverse probability treatment weighting achieved good covariate balance between groups. Over a median follow-up duration of 3.0 years (interquartile range 1.7-5.0 years), 1115 patients (45.0%) had MACEPRONOUNCE and 344 (13.9%) had MACECVM. GnRH agonist users had lower risks of MACEPRONOUNCE (Log-rank P < 0.001) and MACECVM (Log-rank P = 0.027). However, no differences were observed within 1 year of follow-up (MACEPRONOUNCE: Log-rank P = 0.308; MACECVM: Log-rank P = 0.357). Among patients without cardiovascular risk factors at baseline, GnRH agonist users had lower risks of MACEPRONOUNCE (Log-rank P < 0.001) and MACECVM (Log-rank P = 0.001), whereas no differences were observed in those with such risk factor(s) (MACEPRONOUNCE: Log-rank P = 0.569; MACECVM: Log-rank P = 0.615). CONCLUSIONS: GnRH antagonists may be associated with higher long-term, but not short-term, cardiovascular risks than agonists in Asian patients with PCa, particularly in those without known cardiovascular risk factors.

Resection of focally progressive gastrointestinal stromal tumours resistant to imatinib therapy.

AIMS: To analyse the outcome of patients with gastrointestinal stromal tumour (GIST) who receive imatinib therapy and undergo subsequent resection of focally progressive disease. METHODS: We reviewed the records of all cases of GIST discussed at the West of Scotland Sarcoma regional multi-disciplinary team meeting between January 2002 and December 2009 inclusive. We analysed all patients who had undergone surgery for progressive disease on imatinib therapy. Focally progressive disease was diagnosed on computated tomography (CT) and positron-emission tomography-CT and was defined by a GIST lesion initially responsive to imatinib therapy but then underwent growth with evidence of metabolic activity. All procedures were undertaken in a university teaching hospital by a single surgeon. RESULTS: Nine patients were identified who underwent ten resections of focally progressive GIST. Six had previously undergone resection of their primary tumour while three had presented with un-resectable disease. Nine operations were for resection of a solitary progression while one operation was for three foci of progression. Five patients underwent liver resection which was confined to the segments were there was focal progression of GIST; of these one patient had multiple liver metastases and portal hypertension with a mass at the porta hepatis. The absolute survival for patients after resection was 18.4±13.7 months (mean±standard deviation), with progression free survival of 14.1±13.5 months equating to 56% at 1-year. Four patients had been switched from imatinib to sunitinib, for further multi-focal progression. CONCLUSIONS: Surgical resection of focally progressive GIST may prolong survival and a second or third resection is a feasible option in selected patients.

Ivabradine: pre-clinical and clinical evidence in the setting of ventricular arrhythmias.

BACKGROUND: Ivabradine, an agent lowering the heart rate, acting as a funny current (If) specific inhibitor, is responsible for the sinoatrial node's spontaneous depolarization. According to current guidelines, it is indicated in specific heart failure populations and as a second-line treatment option to improve angina in chronic coronary syndromes. REVIEW OF LITERATURE: The role of ivabradine in the setting of ventricular arrhythmias has been studied in both experimental and clinical studies. Specifically, experimental studies have examined the role of ivabradine in acute myocardial ischemia, reperfusion, digitalis-induced ventricular arrhythmias, and catecholaminergic polymorphic ventricular tachycardia showing promising results. In addition, clinical studies have shown a beneficial role of ivabradine in reducing ventricular arrhythmias. Ivabradine reduced premature ventricular contractions in combination with beta-blockers in dilated cardiomyopathy patients. Similarly, in catecholaminergic polymorphic ventricular tachycardia, ivabradine reduced dobutamine-induced premature ventricular complexes and improved ventricular arrhythmias burden. On the other hand, current data show no beneficial role of ivabradine in reducing ventricular arrhythmias in myocardial ischemia. CONCLUSIONS: Randomized clinical trials are needed to elucidate the role of ivabradine in reducing the burden of ventricular arrhythmias in various clinical settings. HIPPOKRATIA 2022, 26 (2):49-54.

Temporal trend and survival impact of infection source among patients with sepsis: a nationwide study.

BACKGROUND: To determine the temporal trends of incidence and outcome based on different sources of sepsis using a nationwide administrative database. METHODS: From 2002 to 2012, the entire Taiwan's health insurance claims data of emergency-treated and hospital-treated sepsis were analysed for incidence and mortality trends. The information about patients with sepsis and sources of sepsis was identified using a set of validated International Classification of Diseases, ninth revision, clinical modification (ICD-9-CM) codes. The 30-day all-cause mortality was verified by linked death certificate database. RESULTS: A total of 1 259 578 episodes of sepsis were identified during the 11-year study period. Lower respiratory tract infection is the most common source of sepsis in patients, with the highest mortality rate. The incidence of genitourinary tract infection has the fastest growing rate. The sepsis mortality was declining at different rates for each source of sepsis. Co-infections in patients with sepsis are associated with higher mortality rate. CONCLUSION: The temporal trends of sepsis incidence and mortality varied among different sources of sepsis, with lower respiratory tract being the highest burden among patients with sepsis. Furthermore, sources of sepsis and the presence of co-infection are independent predictors of mortality. Our results support source-specific preventive and treatment strategies for future sepsis management.

The association of hematological indices with the response to cardiac resynchronization therapy: a single-center study.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established therapeutic option for patients with heart failure (HF) and left ventricular ejection fraction (LVEF) ≤35 % who meet specific criteria according to current guidelines. However, up to 40 % of patients have no response to CRT. Our study aimed to investigate the association between different hematological and biochemical indices and response to CRT. METHODS: Patients with HF due to ischemic or dilated cardiomyopathy referred to our hospital for CRT implantation from January 2013 to November 2017 were included in the study. Response to CRT was defined as an increase in LVEF ≥10 % or a decrease in left ventricular end-systolic volume (LVESV) ≥15 % at six months of follow-up. RESULTS: A total of 48 patients (mean age: 66.2 ± 9.5 years, 81.3 % males) were included in the study. Of these HF patients, 29 (60.4 %) had ischemic cardiomyopathy, and 19 (39.6 %) had dilated cardiomyopathy. At six months of follow-up, 37 patients (77.1 %) had responded to CRT. Ten patients (20.8 %) had ventricular tachycardia (VT), 24 (50 %) patients were hospitalized, and two patients (4.2 %) died during the follow-up period. Multivariate analysis demonstrated that age (p =0.03) and creatinine levels (p =0.02) were independent predictors of the response to CRT. No significant associations between hematological markers (white blood cells, neutrophils, lymphocytes, platelets, neutrophil to lymphocyte ratio, red blood cells distribution width) and CRT response were observed. CONCLUSIONS: A smaller increase in LVEF and a smaller decrease in LVESV were predictive for VT occurrence and hospitalizations in patients receiving CRT. No significant association between hematological markers and response to CRT was found. HIPPOKRATIA 2019, 23(3): 118-125.

Combining procalcitonin with the qSOFA and sepsis mortality prediction.

To investigate whether procalcitonin (PCT) can improve the performance of quick sequential organ failure assessment (SOFA) score in predicting sepsis mortality, we conducted a retrospective multicenter cohort study with independent validation in a prospectively collected cohort in 3 tertiary medical centers. Patients with presumed sepsis were included. Serum PCT levels were measured at admission. Quick SOFA score and systemic inflammatory response syndrome (SIRS) criteria were calculated for each patient. PCT levels were assigned into 0, 1, and 2 points for a serum level of <0.25, 0.25 to 2, and >2 ng/mL, and added to the quick sepsis-related organ failure assessment (qSOFA) score. The incremental value of PCT to qSOFA was then evaluated by logistic regression, receiver-operating characteristic (ROC) curve, and reclassification analysis.In all, 1318 patients with presumed severe infection were enrolled with a 30-day mortality of 13.5%. Serum level of PCT showed a high correlation with qSOFA score and 30-day inhospital mortality. The area under the ROC curve was 0.56 for SIRS criteria, 0.67 for qSOFA score, and 0.73 for qSOFA_PCT in predicting 30-day mortality. The risk prediction improvement was reflected by a net reclassification improvement of 35% (17%-52%). Incorporation of PCT into the qSOFA model could raise the sensitivity to 86.5% (95% confidence interval 80.6%-91.2%). In the validation cohort, qSOFA_PCT greatly improved the sensitivity to 90.9%.A simple modification of qSOFA score by adding the ordinal scale of PCT value to qSOFA could greatly improve the suboptimal sensitivity problem of qSOFA and may serve as a quick screening tool for early identification of sepsis.

Laparoscopic hernia repair.

The laparoscope was first invented in the early 20th century. The first laparoscopic hernia repair was in 1990. Despite almost 20 years of laparoscopic hernia repair experience, open hernia surgery remains the main stay of hernia surgery today. This review looks at current evidence and guidelines on the use of laparoscopic hernia repair surgery.

Meta-analysis on shift work and risks of specific obesity types.

AIMS: This systematic review and meta-analysis evaluated the associations between shift work patterns and risks of specific types of obesity. METHODS: PubMed was searched until March 2017 for observational studies that examined the relationships between shift work patterns and obesity. Odds ratio for obesity was extracted using a fixed-effects or random-effects model. Subgroup meta-analyses were carried out for study design, specific obesity types and characteristics of shift work pattern. RESULTS: A total of 28 studies were included in this meta-analysis. The overall odds ratio of night shift work was 1.23 (95% confidence interval = 1.17-1.29) for risk of obesity/overweight. Cross-sectional studies showed a higher risk of 1.26 than those with the cohort design (risk ratio = 1.10). Shift workers had a higher frequency of developing abdominal obesity (odds ratio = 1.35) than other obesity types. Permanent night workers demonstrated a 29% higher risk than rotating shift workers (odds ratio 1.43 vs. 1.14). CONCLUSION: This meta-analysis confirmed the risks of night shift work for the development of overweight and obesity with a potential gradient association suggested, especially for abdominal obesity. Modification of working schedules is recommended, particularly for prolonged permanent night work. More accurate and detailed measurements on shift work patterns should be conducted in future research.

Acute Cellular Rejection and Infection Rates in Alemtuzumab vs Traditional Induction Therapy Agents for Lung and Heart Transplantation: A Systematic Review and Meta-analysis.

BACKGROUND AND OBJECTIVES: Heart and lung transplantation is a high-risk procedure requiring intensive immunosuppressive therapy for preventing organ rejection. Alemtuzumab, a CD52-specific monoclonal antibody, is increasingly used for induction therapy compared with conventional agents. However, there has been no systematic review comparing its efficacy with traditional therapeutic drugs. METHODS: PubMed and EMBASE were searched to October 1, 2017, for articles on alemtuzumab in cardiothoracic transplant surgery. Of the 433 studies retrieved, 8 were included in the final meta-analysis. RESULTS: In lung transplantation, alemtuzumab use was associated with lower odds of acute cellular rejection compared with antithymocyte globulin (odds ratio [OR], 0.21; 95% CI, 0.11-0.40; P < .001), lower acute rejection rates (OR, 0.12; 95% CI, 0.03-0.55; P < .01), and infection rates (OR, 0.69; 95% CI, 0.35-1.36; P = .33) when compared with basiliximab. Multivariate meta-regression analysis found that mean age, male sex, single lung transplant, double lung transplant, cytomegalovirus or Epstein-Barr virus status, idiopathic pulmonary fibrosis, cystic fibrosis, and mean ischemic time did not significantly influence acute rejection outcomes. For heart transplantation, alemtuzumab use was associated with lower acute rejection rates when compared with tacrolimus (OR, 0.44; 95% CI, 0.30-0.66; P < .001). CONCLUSIONS: Alemtuzumab use was associated with lower rejection rates when compared with conventional induction therapy agents (antithymocyte globulin, basiliximab, and tacrolimus) in heart and lung transplantation. However, this was based on observational studies. Randomized controlled trials are needed to verify its clinical use.

WITHDRAWN: Acute Cellular Rejection and Infection Rates in Alemtuzumab vs Traditional Induction Therapy Agents for Lung and Heart Transplantation: A Systematic Review and Meta-analysis.

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Transplant Proc. 2018; 50 (10):3739-3747, https://doi.org/10.1016/j.transproceed.2018.08.018. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

The role of immunohistochemistry for smooth-muscle actin, p63, CD10 and cytokeratin 14 in the differential diagnosis of papillary lesions of the breast.

BACKGROUND: Histological differentiation of mammary papillary lesions can be difficult. The evaluation of myoepithelial cells can be helpful, with benign papilloma showing a continuous myoepithelial cell layer, which becomes attenuated or absent in malignant papillary lesions. METHODS: A large series of 100 papillomas (28 papillomas with florid epithelial hyperplasia) and 68 papillary carcinomas (9 invasive, 44 in situ, and 15 ductal carcinomas in situ (DCIS) involving papillomas) of the breast were stained for myoepithelial cells by immunohistochemistry using antibodies to smooth-muscle actin (SMA), p63, CD10 and cytokeratin (CK) 14. RESULTS: In the papillomas, using these four antibodies, myoepithelial cells were positive in 88%, 99%, 91% and 95% of cases, respectively, with SMA showing marked stromal component cell staining and CD10 showing epithelial and stromal staining. CK14 also showed epithelial staining in 71% of papillomas and 96% of papillomas with florid epithelial hyperplasia. In the papillary carcinomas, 36 (53%) cases showed staining of myoepithelial cells that were scattered, discontinuous and diminished in number and the remaining 32 (47%) cases did not show myoepithelial cells. Invasive papillary carcinoma has the lowest proportion (33%) with myoepithelial cells, and DCIS involving papillomas had the highest proportion (87%). CONCLUSIONS: p63 had the highest sensitivity and did not cross-react with stromal cells and only rarely with epithelial cells. CK14 has the added ability to distinguish between florid epithelial hyperplasia involving papilloma and DCIS involving papillomas. CK14 and p63 may be used as an adjunct in assessing difficult papillary lesions of the breast.