Diet and ovarian cancer risk: a case-control study in China

This case-control study, conducted in Zhejiang, China during 1999-2000, investigated whether dietary factors have an aetiological association with ovarian cancer. Cases were 254 patients with histologically confirmed epithelial ovary cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplasm hospital outpatients without long-term diet modifications and 51 women recruited from the community. A validated food frequency questionnaire was used to measure the habitual diet of cases and controls. The risks of ovarian cancer for the dietary factors were assessed by adjusted odds ratios based on multivariate logistic regression analysis, accounting for potential confounding demographic, lifestyle, familial factors and hormonal status, family ovarian cancer history and total energy intake. The ovarian cancer risk declined with increasing consumption of vegetables and fruits but vice versa with high intakes of animal fat and salted vegetables. The adjusted upper quartile odds ratio compared to the lower quartile was 0.24 (0.1-0.5) for vegetables, 0.36 (0.2-0.7) for fruits, 4.6 (2.2-9.3) for animal fat and 3.4 (2.0-5.8) for preserved (salted) vegetables with significant dose-response relationship. The risk of ovarian cancer also appeared to increase for those women preferring fat, fried, cured and smoked food.

Public versus private hospital maternity length of stay: a gamma mixture modelling approach

Application of a gamma mixture model to obstetrical diagnosis-related groups (DRGs) revealed heterogeneity of maternity length of stay (LOS). The proportion of long-stay subgroups identified, which can account for 30% of admissions, varied between DRGs. The burden of long-stay patients borne was estimated to be much higher in private hospitals than public hospitals for normal delivery, but vice versa for Caesarean section. Such differences highlights the impact of DRG-based casemix funding on inpatient LOS and have significant implications for health insurance companies to integrate casemix funding across the public and private sectors. The analysis also benefits hospital administrators and managers to budget expenditures accordingly.

Determinants of maternity length of stay: a Gamma mixture risk-adjusted model

With obstetrical delivery being the most frequent cause for hospital admissions, it is important to determine health- and patient-related characteristics affecting maternity length of stay (LOS). Although the average inpatient LOS has decreased steadily over the years, the issue of the appropriate LOS after delivery is complex and hotly debated, especially since the introduction of the mandatory minimum-stay legislation in the USA. The purpose of this paper is to identity factors associated with maternity LOS and to model variations in LOS. A Gamma mixture risk-adjusted model is proposed in order to analyze heterogeneity of maternity LOS within obstetrical Diagnosis Related Groups (DRGs). The determination of pertinent factors would benefit hospital administrators and clinicians to manage LOS and expenditures efficiently.

Zero-inflated Poisson regression with random effects to evaluate an occupational injury prevention programme

This study presents a zero-inflated Poisson regression model with random effects to evaluate a manual handling injury prevention strategy trialled within the cleaning services department of a 600 bed public hospital between 1992 and 1995. The hospital had been experiencing high annual rates of compensable injuries of which over 60 per cent were attributed to manual handling. The strategy employed Workplace Risk Assessment Teams (WRATS) that utilized a workplace risk identification, assessment and control approach to manual handling injury hazard reduction. The WRATS programme was an intervention trial, covering the 1988-1995 financial years. In the course of compiling injury counts, it was found that the data exhibited an excess of zeros, in the context that the majority of cleaners did not suffer any injuries. This phenomenon is typical of data encountered in the occupational health discipline. We propose a zero-inflated random effects Poisson regression model to analyse such longitudinal count data with extra zeros. The WRATS intervention and other concomitant information on individual cleaners are considered as fixed effects in the model. The results provide statistical evidence showing the value of the WRATS programme. In addition, the methods can be applied to assess the effectiveness of intervention trials on populations at high risk of manual handling injury or indeed of injury from other hazards.

Determining the effects of patient casemix on length of hospital stay: a proportional hazards frailty model approach

OBJECTIVES

To identify factors associated with hospital length of stay (LOS) and to model variations in LOS within Diagnosis Related Groups (DRGs).

METHODS

A proportional hazards frailty modelling approach is proposed that accounts for patient transfers and the inherent correlation of patients clustered within hospitals. The investigation is based on patient discharge data extracted for a group of obstetrical DRGs.

RESULTS

Application of the frailty approach has highlighted several significant factors after adjustment for patient casemix and random hospital effects. In particular, patients admitted for childbirth with private medical insurance coverage have higher risk of prolonged hospitalization compared to public patients.

CONCLUSIONS

The determination of pertinent factors provides important information to hospital management and clinicians in assessing the risk of prolonged hospitalization. The analysis also enables the comparison of inter-hospital variations across adjacent DRGs.

Measuring resident satisfaction in residential aged care

PURPOSE

The aims of this study were to assess the factor structure, reliability, and validity of an existing Resident Satisfaction Questionnaire (RSQ) and to develop a short-form RSQ for regular use in residential aged care settings.

DESIGN AND METHODS

A cross-sectional survey design was adopted to collect the required information, with facilities being selected using stratified random sampling. Both exploratory and confirmatory factor analyses were conducted on a sample of 1,146 residents in 70 residential aged care facilities in Western Australia.

RESULTS

The RSQ is confirmed to be a reliable, valid, context-relevant, and easy-to-use instrument for assessing residents' satisfaction with their residential aged care facilities. Resident satisfaction, as assessed via the RSQ, was found to be a multidimensional construct comprising six factors-Room, Home, Social Interaction, Meals Service, Staff Care, and Involvement.

IMPLICATIONS

A 24-item short version of the RSQ can be constructed based on the six-factor resident satisfaction measurement model and used as a regular monitoring tool of resident satisfaction for quality improvement purposes.

DNA analysis for the Dombrock polymorphism

BACKGROUND

RBC typing for Do(a) and Do(b) is notoriously difficult, and inaccurate typing can predispose patients to hemolytic transfusion reactions. The DO1/DO2 polymorphism is associated with three nucleotide changes: 378 C>T, 624 T>C and 793 A>G. While the 378 C>T- and 624 T>C-containing codons are silent mutations, the 793 A>G polymorphism in codon 265 encodes asparagine for Do(a) and aspartic acid for Do(b).

STUDY DESIGN AND METHODS

Described here are two PCR-RFLP assays, one using the Mnl I site associated with 624C (DO2) and the other altering two nucleotides within the sense primer, which allows recognition of 793G by the Eam 1105 I.

RESULTS

The assays have been performed on over 100 samples for which the RBC typing of one or both antigens was known. Eight samples had been historically mistyped by hemagglutination.

CONCLUSION

This RFLP assay provides a practical method for typing donor blood for Dombrock alleles.

Sentinel node biopsy for breast cancer may have little to offer four-node-samplers

The aims of the study were to determine how often four node axillary sampling (4NAS) encompasses the sentinel node (SN) and to compare the relative sensitivity of 4NAS with sentinel node biopsy (SNB) for axillary node staging. 200 patients with breast cancer were preoperatively injected with 27 MBq 99m-Tc-labelled colloid adjacent to the tumour. At operation, standard 4NAS was performed. Each node was counted ex vivo using a probe. A search was then made to find a node with higher counts in vivo directed by the probe. If found, it was excised. Each node was submitted separately to pathology. A SN was identified in 191 patients (96%). The SN was contained in the 4NAS in 153 patients (80%) and identified separately in 38 patients (20%). Of 60 node-positive patients, 49 were positive by 4NAS and SNB, the SN was not identified in 2 and in 8 the SN was falsely negative compared with 4NAS. For 1 patient, the SN was positive and the 4NAS negative. SNB performed using radiolabelled colloid has no advantage over 4NAS when nodes are assessed by standard histological technique.

Consultative team to assess manual handling and reduce the risk of occupational injury

OBJECTIVES

To describe the formation of a consultative team to assess the risk of manual handling in the workplace that started in October 1992 within the cleaning services department of a 600 bed hospital, and to evaluate the effectiveness of its recommendations in reducing the rate and severity (time lost and cost) of workers' compensation injury.

METHODS

The consultative team identified, assessed, and recommended controls for manual handling and other injury risks. Data on injuries counted before and after implementation of the team's recommendations were obtained for the cleaning services study group, an orderly services comparison group, as well as cleaners from a peer hospital and for the State of Western Australia. Evaluation of the four groups was undertaken 3 years after the end of the study period, to allow maturation of the costs of the claims (adjusted to July 1998 consumer price index) and hours lost from work.

RESULTS

Statistical analysis showed that implementation of the recommendations significantly reduced numbers and rates of injury, but not the severity of injury, in the cleaning services study group. There was no difference in numbers or severity of injuries for the comparison groups before and after implementation of the recommendations.

CONCLUSIONS

The recommendation of the consultative team can produce a meaningful and sustained reduction in rates of injury within an at risk population. The results support a consultative approach to reducing workplace injuries from manual handling. The team process has potential for application to occupational groups at risk of exposure to other types of hazards.

Determinants of length of stay: implications on differential funding for rural and metropolitan hospitals

This study analysed and compared the determinants of length of inpatient stay between the rural and metropolitan public hospitals. The investigation was based on the 1998/99 Western Australia patient discharge data. A Cox regression model was used due to the high proportion of patient transfers in the rural hospitals. It was found that several variables were associated with length of stay (LOS) variations within Diagnosis Related Groups (DRG). The method provides additional insights to hospital management and clinicians in assessing the risk of prolonged hospitalisation. From a state government perspective, a DRG payment adjustment strategy may be developed for different categories of admitted patient episodes. The analysis has implications on the formulation of differential funding rates between rural and metropolitan hospitals.

Preoperative assessment of prognostic factors in breast cancer

The adoption of preoperative diagnostic strategies involving fine needle aspiration cytology (FNAC) or core biopsy is well established, allowing the planning of operating lists and bed occupancy and patient involvement in therapeutic management. In addition to diagnosis, however, pathologists are increasingly being asked to provide pathological prognostic information from preoperative samples. This leader describes techniques for predicting prognosis and response to treatment on these specimens and some of the problems inherent in the determination of prognosis on small samples. For example, although histological grade can be assessed relatively reliably on either core or FNAC samples, the evaluation of tumour type (which includes an overall assessment of the architecture of a given tumour) may be less reliable on small preoperative samples. Other well recognised histological prognostic factors, such as vascular channel invasion or tumour size, cannot be determined accurately on small preoperative samples. For those patients who might benefit from neoadjuvant treatment, predicting the response to such treatments--for example, by the assessment of oestrogen receptor status--can readily be performed on either core biopsy or FNAC. In the future, other molecular markers such as C-erbB-2 might also prove beneficial in predicting response to newly developed treatments.

Expression of CD34 and bcl-2 in phyllodes tumours, fibroadenomas and spindle cell lesions of the breast

AIMS

Strong expression of CD34 and bcl-2 has been described in solitary fibrous tumours. It has been proposed that these lesions arise from long-lived mesenchymal cells. We tested the hypothesis that spindle cell lesions of the breast arise from similar mesenchymal cells in the mammary stroma.

METHODS AND RESULTS

Sections of phyllodes tumours (26), fibroadenomas (15), myofibroblastomas (two), pseudoangiomatous hyperplasia (five) and myoid hamartoma (one) were stained immunohistochemically for CD34 and bcl-2. Conventional mammary carcinoma is known to be CD34-negative: we therefore stained 11 spindle cell carcinomas and one adenosquamous carcinoma. The mammary stroma, particularly around lobules, stained for CD34. All the lesions (except the carcinomas) showed spindle cell staining for CD34. There was more staining in fibroadenomas than in phyllodes tumours (especially malignant tumours). The staining in phyllodes tumours was typically patchy. In some there was increased or decreased staining adjacent to the epithelium. There were occasional spindle cells positive for bcl-2 in the normal perilobular stroma. bcl-2 was frequently expressed in spindle cells in fibroadenomas, phyllodes tumours and pseudoangiomatous hyperplasia, and rarely in the other lesions.

CONCLUSIONS

The combined expression of CD34 and bcl-2 suggests that fibroadenomas, phyllodes tumours and pseudoangiomatous hyperplasia may arise from long-lived bcl-2-positive mesenchymal cells in the breast in a manner similar to that proposed for solitary fibrous tumours. The absence of CD34 staining in spindle cell carcinomas is of potential diagnostic value in the distinction from malignant phyllodes tumours in difficult cases.

Tumour necrosis factor-alpha and interferon-gamma synergistically activate the RANTES promoter through nuclear factor kappaB and interferon regulatory factor 1 (IRF-1) transcription factors

Inflammatory cytokines such as tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) synergistically activate expression of the RANTES (regulated upon activation, normal T-cell expressed and secreted) gene, which plays a crucial role in the chemoattraction of leukocytes during the inflammatory response. To understand at the molecular level the mechanism by which the two cytokines activate RANTES gene expression, we determined the requirement of cis-acting elements in the RANTES promoter and trans-acting factors. The murine RANTES promoter contained one putative interferon regulatory factor, IRF, and three putative nuclear factor kappaB (NF-kappaB) binding sites. Specific destruction of the IRF binding site and one of the three NF-kappaB binding sites abolished the inducibility of promoter activity by IFN-gamma and TNF-alpha, respectively. In contrast, mutation of the other two putative NF-kappaB binding sites did not affect RANTES promoter activity significantly. In addition, the RANTES promoter was stimulated by co-transfection of plasmids that expressed either p65, an NF-kappaB family protein, or the IRF-1 transcription factor. RANTES promoters with mutations in the NF-kappaB or IRF binding sites were not stimulated by p65 or IRF-1 expression, respectively. In electrophoretic mobility-shift and immunologic assays, we showed that IRF-1 was induced after cells were treated with IFN-gamma and that NF-kappaB was activated by TNF-alpha treatment. These results demonstrate that both NF-kappaB and IRF-1 transcription factors mediate the induction of RANTES expression via their cognate cis-acting elements when cells are stimulated by TNF-alpha and IFN-gamma.

A comparison of 14 and 12 gauge needles for core biopsy of suspicious mammographic calcification

This study was carried out to compare the efficacy of 14 vs 12 G needles in stereotactic core biopsy of mammographic calcification. A consecutive series of 100 impalpable mammographic calcifications, without an associated mass and requiring stereotactic core biopsy were randomly allocated to either 14 G or 12 G needle sampling. All biopsies were performed using an upright stereotactic digital unit (Senovision GE) and a Bard automated biopsy gun. Core biopsy results were categorized as either normal, benign, atypical ductal hyperplasia, suspicious of ductal carcinoma in situ (DCIS), DCIS or invasive cancer. The radiographic calcification retrieval rates, complete and absolute sensitivity for malignancy of DCIS and DCIS with an invasive focus were obtained by comparison of core results with surgical histology. Radiographic calcification retrieval was achieved in 86% when using 14 G and 12 G needles. The absolute sensitivity and complete sensitivity for diagnosing DCIS were the same with 12 G and 14 G needles (72% versus 71% and 93% versus 94%, respectively). The use of 12 G needles does not appear to confer benefit over the use of 14 G needles in the diagnosis of mammographic calcification.

A critical appraisal of existing classification systems of epithelial hyperplasia and in situ neoplasia of the breast with proposals for future methods of categorization: where are we going?

Current classification systems for borderline lesions of the breast including epithelial hyperplasia, atypical hyperplasia, and ductal carcinoma in situ fall short of the ideal. They present pathologists with problems of recognition or clear distinction and clinicians with difficult management choices. In addition, recent evidence indicates that different pathogenetic lesions are present in some categories. This article presents a brief critical appraisal of the existing classifications and offers suggestions for revision using a model of pathogenetic lineage.

The value of central histopathological review of testicular tumours before treatment

OBJECTIVE

To assess the value of central histopathological review of testicular tumours.

MATERIALS AND METHODS

The histopathology reports of the referring hospital and central review were compared for all referred testicular specimens (201 orchidectomies and seven testicular biopsies) from 11 hospitals in one region, between 1992 and 1997.

RESULTS

There were two main findings: First, there was a major discrepancy of tumour type in 12 specimens (6%). The most frequent change (in five cases) was from seminoma to nonseminomatous germ cell tumour (NSGCT). There were also difficulties with uncommon tumours such as spermatocytic seminoma, lymphoma and adenocarcinoma. Treatment was changed as result of the altered diagnosis in eight of these 12 patients. Second, there were discrepancies of interpretation of vascular invasion in 12 of 59 NSGCTs (20%). Differences of tumour elements recognized in NSGCTs were frequent.

CONCLUSIONS

The errors discovered on central histopathological review of testicular tumours were significant, though small in number. This supports the idea of central review and is consistent with the specialization recommended in the Calman-Hine cancer arrangements.

HLA class II DRB1 and DQB1 allelic polymorphism and sclerosing lymphocytic lobulitis of the breast

BACKGROUND

Sclerosing lymphocytic lobulitis is an inflammatory disorder of the breast. The pattern of inflammation, expression of HLA class II DR by breast epithelium and association with autoimmune disorders, particularly insulin dependent diabetes mellitus (IDDM), together suggest an autoimmune aetiology.

AIM

To test the hypothesis that susceptibility to sclerosing lymphocytic lobulitis may be linked to patient HLA class II DRB1 alleles, particularly DRB1*03 and DRB1*04, suggested by a previous small uncontrolled study.

METHODS

HLA class II DRB1 and DQB1 genotypes were compared between a series of 28 sclerosing patients with lymphocytic lobulitis and 300 controls, using polymerase chain reaction (PCR) based typing of DNA extracted from formalin fixed, paraffin embedded biopsies.

RESULTS

Results from the 28 patients (nine with IDDM) showed an increased frequency of DRB1*04 compared with controls (61% v 33%, p = 0.01), but no significant differences for other genotypes. In patients with IDDM, the frequencies of DRB1*04 (89%, p = 0.001) and DQB1*0302 (100% v 21%, p = 0.0001)--a genotype that is in linkage disequilibrium with DRB1*04--were increased compared with controls. However, in the patients without IDDM, the frequencies of DRB1*04 (50%) and DQB1*0302 (14%) were not significantly increased.

CONCLUSIONS

The increased frequency of HLA DRB1*04 in sclerosing lymphocytic lobulitis appears to reflect its association with IDDM, a condition in which DRB1*04 is increased in frequency.

DNA inoculations with HIV-1 recombinant genomes that express cytokine genes enhance HIV-1 specific immune responses

Vaccination with HIV-1 DNA sequences induce both humoral and cellular immune responses in experimental animals. However, these responses are relatively weak and are often only transient in their nature. In order to enhance the level of HIV-1 specific immunity, we have engineered HIV-1 DNA constructs which contained various cytokine genes such as interleukin-2 (IL-2), granulocyte-macrophage colony stimulating factor (GM-CSF) and interferon-gamma (IFN-gamma) gene. These constructs have deleted the tat and nmf genes of HIV-1 to eliminate their immunosuppressive effects. Immunizations with these recombinant constructs elicited moderate proliferative T cell responses but poor antibody responses in rats. However, inoculations of HIV-1 DNA that contained the GM-CSF or the IL-2 gene significantly enhanced humoral and proliferative T cell responses, respectively. Thus, recombinant HIV-1 genomes such as those described here may increase the efficacy of DNA vaccination.

Angiogenesis and expression of thymidine phosphorylase by inflammatory and carcinoma cells in ductal carcinoma in situ of the breast

Angiogenesis is essential for tumour growth and important in metastasis and for prognosis in invasive carcinoma of the breast. Two patterns of increased vascularity have been shown in mammary ductal carcinoma in situ (DCIS): a cuff of vessels close to the involved ducts, and vessels in the interductal stroma. Inflammation may potentially promote angiogenesis by release of angiogenic factors and digestive enzymes. A correlation has previously been found between the intensity of perivascular inflammation and stromal vascularity in DCIS, but no strong relationship has been observed between inflammation and angiogenesis in invasive carcinoma. Tumour angiogenesis is regulated by a number of angiogenic factors, including thymidine phosphorylase (platelet-derived endothelial cell growth factor), which is expressed at high levels in macrophages. Using immunohistochemical methods, thymidine phosphorylase expression and vascularity have been studied in DCIS (n = 34) and invasive carcinoma (n = 32). Stromal vascularity in DCIS was associated with thymidine phosphorylase expression in the perivascular inflammatory cells and in the cytoplasm of carcinoma cells. In invasive carcinoma, no relationship was found between vascularity and thymidine phosphorylase expression in either the carcinoma or the inflammatory cells. This study suggests that thymidine phosphorylase expression in both inflammatory and carcinoma cells may contribute to one of the patterns of vascularity in DCIS, but not in invasive disease.

Post-mortem examination after cardiac surgery

Following a recent enquiry into surgery at a paediatric cardiac centre in England, there will be substantial changes in the way that the success and failure of surgical procedures will be monitored and investigated. Post-mortem examinations on patients dying after cardiac surgery are likely to be performed and reported in more detail. This review describes the protocol that we have developed and summarizes recent clinical and pathological studies that have increased our understanding of postoperative pathophysiology. Close attention should be paid to the history, particularly the operation note. Cardiac failure is the commonest cause of death. We believe this is a clinicopathological diagnosis and provide definitions of preoperative and perioperative cardiac failure. Haemorrhage, stroke, pulmonary emboli and infection are other important causes of death. Methods of dissection are suggested for bypass grafts and valve replacements. Two recent studies show that the post-mortem examination provides answers to most clinical questions and reveals an unexpected cause of death in 10-15% of patients. There are limitations however: an incomplete or indeterminate cause of death is found in 14-25% of patients, most commonly sudden clinically unexplained death or clinically unexplained cardiac failure soon after surgery.

A discordancy test approach to identify outliers of length of hospital stay

A discordancy test approach is proposed to identify outliers of inpatient length of stay. This has implications not only for benchmarking service delivery but also for linking budget allocation procedures to efficiency of health service provisions. The effects of shifting trim point thresholds on hospital payments are assessed in a case study of a group of obstetrical patients.

Invasive lobular and invasive ductal carcinoma of the breast show distinct patterns of vascular endothelial growth factor expression and angiogenesis

Angiogenesis is essential for tumour growth and important in tumour metastasis and prognosis. Vascular endothelial growth factor (VEGF) stimulates endothelial proliferation in vitro and angiogenesis in vivo. VEGF expression has been correlated with high vascularity in tumours, including carcinoma of the breast. This study investigated VEGF expression and vascularity of invasive lobular (n = 10) and invasive ductal carcinoma (n = 28), and pure ductal carcinoma in situ of the breast (n = 33). VEGF protein expression was studied with immunohistochemistry and VEGF mRNA with in situ hybridization. Vascular density was assessed on sections stained for von Willebrand factor. There was more expression of both VEGF protein (P = 0.006) and mRNA (P = 0.002) in invasive ductal than in invasive lobular carcinoma. VEGF protein (rs = 0.32, P = 0.047) and mRNA (rs = 0.56, P = 0.04) correlated with vascular density in invasive ductal carcinoma. In invasive lobular carcinoma, vascular density did not correlate with VEGF mRNA (rs = 0.15, P = 0.35) and was inversely related to VEGF protein (rs = -0.57, P = 0.04). There were no significant differences in vascular density between the two types of invasive carcinoma, suggesting that VEGF is important in angiogenesis in invasive ductal carcinoma, but that other angiogenic factors are important in invasive lobular carcinoma. Although VEGF protein was frequently expressed in ductal carcinoma in situ, no relationship was found between VEGF and the two patterns of angiogenesis previously described.

Sensitivity of parametric link functions in generalized linear models

A common method of choosing the link function in generalized linear models is to specify a parametric link family indexed by unknown parameters. The maximum likelihood estimates of such link parameters, however, may often depend on one or several extreme observations. Diagnostics are derived to assess the sensitivity of the parametric link analysis. Two examples demonstrate that the proposed diagnostics can identify jointly influential observations on the link even when masking is present.

Heterogeneity of intracellular pH and of mechanisms that regulate intracellular pH in populations of cultured cells

Cells within solid tumors are known to exist in a microenvironment that may be acidic and depend on membrane-based mechanisms (Na+/H+ antiport and Na+-dependent Cl-/HCO3- exchanger) that regulate intracellular pH (pHi). We have used the fluorescent pH indicator 2',7'-bis-(2-carboxyethyl) 5 (and 6)-carboxyfluorescein and flow cytometry to study the distribution of pHi and the activity of these pHi-regulating mechanisms among populations of murine mammary sarcoma (EMT6), human breast cancer (MCF-7), and Chinese hamster ovary cells exposed to different levels of extracellular pH (pHe). Cells were exposed to Na+ buffer in the presence or absence of HCO3- and of 5-(N-ethyl-N-isopropyl)-amiloride (a potent inhibitor of the Na+/H+ antiport) to determine the relative importance of each exchanger in the regulation of pHi. Our results indicate that: (a) the distribution of pHi at any value of pHe is broader than can be accounted for by machine noise; (b) cells maintain levels of pHi that are higher than pHe under acidic conditions; (c) the distribution of pHi is narrower when the Na+-dependent Cl-/HCO3- exchanger is active; and (d) populations that are derived from selected cells with values of pHi at lower and higher ends of the pHi distribution generate pHi distributions that are similar to those of controls, suggesting a stochastic variation in the activity of membrane-based mechanisms that regulate pHi. Our data suggest that the Na+-dependent Cl-/HCO3- exchanger is the dominant mechanism for regulation of pHi under moderately acidic conditions such as may occur in the microenvironment of solid tumors.

Cyclin D1 and associated proteins in mammary ductal carcinoma in situ and atypical ductal hyperplasia

Experimental studies suggest that cyclin D1 is a potential oncogene but in clinical studies of invasive breast cancer, overexpression of cyclin D1 is found to be associated with oestrogen receptor (ER) expression and low histological grade, both markers of good prognosis. Immunohistochemistry has been used to examine the relationship between cyclin D1 expression and differentiation in 36 cases of ductal carcinoma in situ (DCIS) and the interrelationship between expression of cyclin D1, its associated protein product of the retinoblastoma gene (pRb), and ER, in this group of cases. The expression of these markers has also been examined in nine cases of atypical ductal hyperplasia (ADH) and these results have been compared with the levels of expression seen in DCIS. Cyclin D1 overexpression was found in 23/36 (64 per cent) cases of DCIS and, in contrast to invasive carcinoma, there was no relationship with either differentiation or ER expression. The level of pRb expression was significantly associated with cyclin D1 expression (rS = 0.49, P = 0.001) and only two cases (6 per cent) were pRb-negative. There was no association between pRb and differentiation of DCIS or ER status. In contrast to DCIS, only one case of ADH showed overexpression of cyclin D1 (Mann-Whitney U-test, P = 0.02). All cases of ADH were ER-positive and showed moderate pRb staining, similar to that seen in well-differentiated DCIS. These results provide further evidence that overexpression of cyclin D1 plays a role early in carcinogenesis.

Vascular density does not predict future metastatic disease in clinical stage 1 non-seminomatous germ cell tumours of the testis

AIM

This study aimed to determine whether patients with stage 1 testicular non seminomatous germ cell tumours (NSGCT) with high vascular density have a greater risk of disease recurrence than those with a low vascular density.

METHODS AND RESULTS

Orchidectomy specimens from 42 patients with stage 1 NSGCT, treated by orchidectomy and surveillance alone, were studied. Vessel density was counted in tumour sections immunohistochemically stained for CD34. The mean of the three highest counts (x250, field size 0.67 mm2) for each tumour was used. Tumour vessel density was very similar for relapsing and non relapsing patients. Vascular invasion was the only variable significantly predictive of disease recurrence at 2 years post-orchidectomy (P = 0.025). There was wide variation of vessel counts between different blocks of a tumour, compared with interobserver variation. The tumour tissue type in the area of highest vessel density was embryonal carcinoma in 50% and teratoma (mature or immature) in 38%.

CONCLUSIONS

We confirmed the value of vascular invasion as a prognostic marker in stage 1 NSGCT. Tumour vessel density was of no prognostic value. Two factors may contribute to this. First, there was wide variation of vessel density between different blocks of a tumour. Second, the most vascular area in a tumour was frequently in low-grade tumour.

Protective immunity against heterologous challenge with encephalomyocarditis virus by VP1 DNA vaccination: effect of coinjection with a granulocyte-macrophage colony stimulating factor gene

For DNA vaccination studies, recombinant VP1 protein of encephalomyocarditis virus (EMCV) was produced from Escherichia coli, and eukaryotic VP1 expression vector, pCT-Gs-VP1, was generated and used as a DNA vaccine. Mice were immunized intramuscularly (i.m.) with pCT-Gs-VP1 in the presence or absence of plasmid DNA expressing granulocyte-macrophage colony stimulating factor (GM-CSF), and were subsequently analyzed for their anti-VP1 immune responses with recombinant VP1 in ELISA. Immunization of mice with pCT-Gs-VP1 resulted in VP1-specific immune response and 43% protection from subsequent lethal heterologous challenge of EMCV. Coinjection of mice with pCT-Gs-VP1 and plasmid DNA encoding GM-CSF was shown to increase the seroconversion rate of the immunized mice with a single DNA injection, and enhanced to a higher degree VP1-specific immunity, which appeared to result in better protection (about 80%) from lethal virus challenge. Thus, our results provide evidence for the potential use of GM-CSF to induce better immune response and resistance against viral infection in DNA vaccination.

Comparison of various expression plasmids for the induction of immune response by DNA immunization

Intramuscular injection of plasmid DNA is an efficient method to introduce a foreign gene into a live animal. We investigated several factors affecting the gene transfer efficiency and the following immune response by intramuscular injection of plasmid DNA. When the strength of several highly efficient viral promoters was compared in muscle by using the chloramphenicol acetyltransferase (CAT) gene as an indicator, cytomegalovirus (CMV) immediate early promoter was found to be stronger than any other viral promoters including Rous sarcoma virus (RSV), murine leukemia virus (SL3-3) and simian virus 40 (SV40) early promoters. Inclusion of adenovirus tripartite leader (TPL) sequences and a synthetic intron in the 5' untranslated region of mRNA moderately stimulated the CAT expression. On the other hand, the expression of encephalomyocarditis virus (EMCV) VP1 gene was greatly enhanced by the TPL sequences and an intron. The level of humoral immune response by intramuscular injection of various VP1 expression plasmids was compared. The seroconversion rate was highly dependent on the strength of the expression vector. However, the ratio of IgG1 and IgG2a immune response was not significantly variable depending on the strength of the expression vector. Also, the efficiency of the sindbis virus-based DNA vector was examined for the gene expression and immune response. Although a high level of CAT expression was obtained in muscle by using this system, VP1 was not produced as much as the conventional expression vectors. Furthermore, little humoral immune response was elicited by intramuscular injection of VP1-expressing sindbis vector, suggesting that this system was not superior to the conventional vector for DNA immunization.

Angiogenesis and inflammation in invasive carcinoma of the breast

AIM

To investigate the relation between angiogenesis and inflammation in invasive carcinoma of the breast.

METHODS

Sections from 75 invasive carcinomas of the breast were stained using immunohistochemistry for von Willebrand factor, CD3, CD8, CD45RO, CD45RA, CD20, CD68, and c-erbB-2. Tumour vascularity was assessed by counting vessels in the three most vascular areas, and calculating the average (x 400 magnification, field 0.168 mm2). Each pattern of inflammation was scored semiquantitatively.

RESULTS

The main pattern of inflammation was a diffuse infiltrate of macrophages, and to a lesser extent T cells. Perivascular and perilobular clusters of B and T cells were noted at the edge of the carcinomas, but were less prominent than the diffuse inflammation. Diffuse inflammation, particularly macrophages, was associated with high tumour grade, tumour necrosis, large tumour size, and c-erbB-2 expression. Perivascular and perilobular inflammation also increased with tumour grade. Tumour vascularity increased slightly with intensity of diffuse inflammation (Spearman's rank correlation coefficient rs = 0.17, p = 0.08), and was inversely related to perilobular inflammation (rs = -0.23, p = 0.03).

CONCLUSIONS

The correlations between inflammation and vascularity were weak in this study (r2 about 0.04) and thus there was no evidence of an important relation. Discrepancies between this and other studies may be resolved by studying expression of angiogenic cytokines and proteolytic enzymes by tumour infiltrating inflammatory cells, and their relation to tumour vascularity.

Prospective study of the value of necropsy examination in early death after cardiac surgery

OBJECTIVE

To assess the value of necropsy examination in patients dying soon after cardiac surgery, particularly the proportion of clinical questions answered by the necropsy, the frequency of major unexpected findings, and the limitations of the procedure.

DESIGN

A three year prospective study of necropsy examinations in adult patients dying before discharge or within 30 days of cardiac surgery performed under cardiopulmonary bypass in one hospital.

SETTING

Tertiary referral centre.

RESULTS

123 of 2781 patients (4.4%) died in the early postoperative period, and necropsy examination was performed in 108 of these (88%). The mortality after emergency procedures (18%) was much higher than after routine operations (2.6%). The main causes of death were cardiac failure (52%), haemorrhage (14%), cerebral disease (6%), and pulmonary emboli (5%). The necropsy changed the stated cause of death in 16 patients (15%), and answered clinical questions in 24 of 38 patients. In 15 patients necropsy examination did not provide a full explanation of death. Most of these patients died of cardiac failure soon after surgery or were sudden unexpected deaths.

CONCLUSIONS

Necropsy examination in patients dying early after cardiac surgery is valuable as it answers the majority of clinical questions, and shows unexpected findings in a significant proportion of cases.

A Delphi evaluation of the factors influencing length of stay in Australian hospitals

Using a modified Delphi method, the factors influencing length of inpatient stay (LOS) were explored. Row/column effects loglinear modelling was used to compare ratings between the first and second rounds, and between the clinical and non-clinical groups. Rating scale modelling was used to classify and determine the relative importance of each factor. Six important and 48 significant determinants of LOS were found, and four unimportant factors were identified. The relationship among these factors and the implications of this study are explored.

Generation of the replication-competent human immunodeficiency virus type 1 which expresses a jellyfish green fluorescent protein

The gene encoding a red-shifted green fluorescent protein variant (EGFP) was introduced into a human immunodeficiency virus type 1 (HIV-1) molecular clone by replacing the nef gene. The EGFP-expressing HIV-1 replicated efficiently in established human T cells. The expression of EGFP in the virus-infected cells was confirmed by fluorescence microscopy and also by Western blot analysis using the GFP antibodies. The EGFP gene was stably maintained in the viral genome during prolonged passages. EGFP-expressing HIV-1 could be used for anti-HIV-1 drug screening, sorting of virus-infected cells by fluorescence activated cell sorting (FACS) analysis, and for the rapid and simple detection of virus-infected cells by fluorescence microscopy.

Angiogenesis and inflammation in ductal carcinoma in situ of the breast

Several recent studies suggest that vascular density may be an independent prognostic indicator in invasive carcinoma of the breast. Increased vascularity has also been shown in ductal carcinoma in situ (DCIS). The prognostic significance of the inflammatory infiltrate in mammary carcinoma is more controversial, but it could affect angiogenesis by releasing angiogenic factors and digesting matrix. Vascularity and inflammation have been studied in 41 examples of pure DCIS, classified using the method of Holland et al. Immunohistochemistry was performed with antibodies to von Willebrand factor, CD3, CD8, CD45RO, CD45RA, CD20, CD68, and c-erB-2. The main pattern of inflammation was clusters of B and T cells situated either adjacent to involved ducts or in the interductal stroma. Typically, these clusters were around vessels with plump endothelium suggestive of high endothelial venules. A less prominent pattern was a diffuse stromal infiltrate of macrophages and T cells. There were two patterns of increased vascularity associated with DCIS: necklaces of vessels close to the involved ducts and vessels arranged diffusely in the interductal stroma. Each pattern of inflammation and of vascularity was graded semi-quantitatively. Increased stromal vascularity was associated with the perivascular clusters of inflammation; both were associated with c-erB-2 expression and extent of the DCIS. Necklaces of vessels were associated with the diffuse inflammation. Perivascular inflammation and c-erB-2 (but neither pattern of vascularity) were associated with poor differentiation of the DCIS. Thus, different patterns of inflammation are associated with different patterns of vessels. The clusters of B and T cells may be recruited via high endothelial venules induced by the DCIS. Cytokines released by the DCIS and/or the inflammatory cells (clusters or diffuse) may stimulate the two patterns of new vessel formation.

Inflammatory infiltrate in invasive lobular and ductal carcinoma of the breast

The significance of inflammation in carcinoma of the breast is controversial. Little attention has been paid to different patterns of inflammation or inflammation associated with different histological types of carcinoma. We have looked at the pattern of inflammation in 123 invasive mammary carcinomas (including 46 lobular), and characterised the inflammatory cells with immunohistochemistry in 21. We found different patterns of inflammation in ductal and lobular carcinoma. Diffuse inflammation was seen more in ductal carcinoma, particularly of high grade, and was predominantly composed of macrophages and T cells. It was associated with necrosis, but the correlation was weak, suggesting that other factors are important. Perilobular inflammation was seen most frequently in lobular and high-grade ductal carcinomas, particularly at the tumour edge. Perivascular inflammation was also largely at the tumour edge, but was not more common in any tumour type. In contrast to the diffuse inflammation, the perivascular and perilobular inflammation was composed of T and B cells. Normal lobules at the tumour edge showed consistent expression of HLA-DR, whereas lobules away from the tumour were negative. A combination of perilobular and perivascular inflammation composed of B and T cells with epithelial expression of HLA-DR mimicking lymphocytic lobulitis was seen more frequently in lobular than ductal carcinoma.

Sclerosing lymphocytic lobulitis in the male breast

Sclerosing lymphocytic lobulitis is an inflammatory disorder of the breast that is well recognised in women. It has only been reported previously in two men; two further men with the condition are described here. Both presented with a breast mass, and one was an insulin dependent diabetic. Biopsy specimens from both patients showed circumscribed perivascular and, to a lesser extent, periductal collections of B and T lymphocytes. Sclerosing lymphocytic lobulitis in the female breast shows predominantly perilobular inflammation. The predominantly perivascular distribution in men is consistent with the relative paucity of epithelium in the male breast. Interlobular fibrosis with epithelioid fibroblasts was also present.

Primary pure teratoma of the testis

PURPOSE

Despite its histologically benign appearance, primary pure teratoma of the testis is believed to have metastatic potential and behave similarly to other nonseminomatous germ cell tumors. We present our experience with the natural history and management of pure teratoma.

MATERIALS AND METHODS

We reviewed the histological findings and clinical history of 15 patients with primary pure teratoma who were treated during a 15-year period, accounting for 4.2% of all nonseminomatous germ cell tumors treated during the same period. Fourteen patients were available for followup and are included in this report.

RESULTS

In 8 patients the tumor was composed entirely of mature teratoma and in 6 immature elements were also present, although this finding was not associated with an increased frequency of metastatic disease. Carcinoma in situ was found adjacent to the tumor in 12 cases. Of 10 patients with stage I disease at presentation who were entered on a surveillance program only 2 have had relapse. The remaining 4 patients had metastatic disease at presentation and, thus, metastatic disease occurred in a total of 6 of the 14 patients (43%) with a median followup of 46 months (range 5 to 197). Metastatic disease was confined to the retroperitoneum in all 6 patients and only 2 patients had elevated serum marker levels. Five patients were treated with primary chemotherapy followed by resection of a residual mass and in all cases teratoma was identified in the resected mass. One patient underwent surgical excision of a retroperitoneal mass, which contained teratoma and yolk sac tumor, followed by chemotherapy. All patients are alive without evidence of progressive disease.

CONCLUSIONS

In patients with primary pure teratoma of the testis metastatic disease may develop and the metastases may contain other subtypes of nonseminomatous germ cell tumors in addition to teratoma. There is probably a reduced frequency of relapse, which should be considered when advising patients with stage I disease, but otherwise management should be the same as for other testicular nonseminomatous germ cell tumors and the prognosis should be excellent.

CD45RO and CD45RA positive cell populations in idiopathic membranous and IgA glomerulopathy

AIMS

To immunophenotype and quantitate glomerular and interstitial inflammatory cells in cases of idiopathic membranous and IgA glomerulopathy; to correlate cell numbers with aspects of clinical data and renal function.

METHODS

Routine indirect immunoperoxidase staining was performed on frozen section renal biopsy specimens for T and B lymphocyte related antigens, macrophages and MHC class II antigens. Double immunohistochemical staining was performed to identify CD45RO+ and CD45RA+ cells.

RESULTS

In IgA glomerulopathy correlations were found relating interstitial cell numbers to creatinine concentration at biopsy (CD45RO+ and CD45RA+ cells) and follow up creatinine concentration (CD3+, CD4+, CD8+, CD45RO+, and CD45RA+ cells). Also in IgA glomerulopathy mean arterial pressure at biopsy correlated with interstitial cell numbers and most recent follow up creatinine concentration. There were no correlations between glomerular inflammatory cells and renal function in either disease. Double staining showed that although most glomerular CD45RO+ and CD45RA+ cells were macrophages, positive cells in the interstitium were lymphocytes. The interstitial CD45RO+:RA+ ratio in normal renal biopsy specimens was approximately 5:1; for IgA glomerulopathy it was 1.5 and was 1.0 in idiopathic membranous glomerulopathy.

CONCLUSIONS

This study demonstrates that interstitial, and not glomerular, inflammatory cell numbers correlate with renal function in primary glomerular disease and that double staining is necessary to interpret positive immunostaining for antigens located on more than one type of inflammatory cell. Detailed investigation of the interstitial CD45RO+ and CD45RA+ cells may give an insight into the pathogenesis of glomerular disease.

Metastatic breast carcinoma with appearance resembling micropapillary ductal carcinoma in situ

AIM

To investigate tumour in an axillary lymph node resembling micropapillary ductal carcinoma in situ.

METHODS

Sections of tumour in the breast and axillary lymph node were stained with haematoxylin and eosin, and immunohistochemically with antibodies to basement membrane and myoepithelial cells.

RESULTS

Tumour in both the breast and axillary lymph node contained areas resembling micropapillary ductal carcinoma in situ. Surrounding these islands, there was a band of eosinophilic material resembling basement membrane and spindle cells that in places appeared to lie outside the basement membrane. Micropapillary tumour at both sites showed weak and discontinuous staining for collagen IV and laminin. The spindle cells stained for alpha-smooth muscle actin, but not for S100. By contrast, immunohistochemistry showed complete rings of basement membrane and myoepithelial cells around definite ductal carcinoma in situ and normal breast lobules and ducts.

CONCLUSIONS

Invasive primary and metastatic carcinoma of the breast can have a growth pattern resembling micropapillary ductal carcinoma in situ.

Orchiectomy after chemotherapy in patients with metastatic testicular cancer. Is it indicated?

BACKGROUND

A small proportion of patients with testicular germ cell tumors present with widely metastatic disease and are treated initially with chemotherapy. Little is known about the efficacy of systemic chemotherapy in eradicating the primary testicular germ cell cancer; however, there is concern that the testis may act as a sanctuary site for germ cell cancer in these patients, and orchiectomy, is, therefore, recommended after chemotherapy.

METHODS

The results from a clinical and pathologic review of 24 patients who underwent delayed orchiectomy after chemotherapy are presented. The testicular pathologic findings are correlated with those in extragonadal masses and also with a blinded review of postchemotherapy testicular ultrasound scans.

RESULTS

The most common testicular pathological finding was a dense fibrous scar that was found in all patients. Three patients had persistent testicular germ cell cancer, six had mature teratoma, and one had carcinoma in situ. There was a strong concordance between the major testicular pathologic findings and those in the resected extragonadal masses. All three patients with persistent testicular germ cell cancer subsequently had disease progression in the extragonadal sites. Testicular ultrasound examination did not distinguish accurately between residual tumor or scar in the testis.

CONCLUSION

Persistence of the primary testicular germ cell cancer is most likely due to the same heterogeneous response to chemotherapy observed in different metastatic sites. Because current imaging techniques cannot identify accurately those patients with residual testicular germ cell cancer or related testicular abnormalities that may predispose to subsequent relapse, orchiectomy after chemotherapy remains appropriate.

Influence diagnostics for generalized linear measurement error models

We study influence diagnostics for generalized linear models when the true covariates are unobservable but measured with error. Based on the bias-corrected estimation of model parameters, diagnostic measures are developed to identify outlying and influential observations. The magnitude of influence is then assessed via a simulated envelope approach. The proposed diagnostic procedure is illustrated on two examples.