Surgical management of an Irish cohort of BRCA-mutation carriers

Little information is available regarding the management of BRCA-related breast cancer in Ireland. A cancer genetics programme was initiated in 1992 at our institution to provide counselling and expert management for those with cancers resulting from inherited predisposition. We examined a cohort of BRCA mutation-carriers treated at a single institution over 16 years. A total of 107 women from 57 families were found to be carriers of mutations in BRCA1/2. Bilateral salpingo-oophorectomy was the most common prophylactic surgery performed. Overall survival between BRCA-related and sporadic breast cancer was equivalent. This is the first publication on surgical management of BRCA-mutation carriers in Ireland. It is imperative that those considered likely to harbour a mutation are referred early to a dedicated clinic so that appropriate counselling, testing and subsequent management to reduce the risk of dying from cancer can be undertaken.

Elevated G2 chromosomal radiosensitivity in Irish breast cancer patients: a comparison with other studies

Previous studies have shown that a significant proportion of breast cancer patients exhibit elevated G2 chromosomal radiosensitivity in contrast to controls (approximately 40%). In this study, the G2 assay was applied to a small number of Irish breast cancer patients who were recorded as sporadic cases and they were compared with a control group to compare and contrast with the previous documented studies. Lymphocyte cultures were set up on whole blood samples and stimulated with phytohaemagglutinin. The cultures were irradiated 74 h later with 0.5 Gy gamma-radiation and cells were arrested in metaphase by treating the cultures with colcemid. The chromosomes were harvested and the aberrations scored per 100 metaphases to assign a G2 score. The assay was first carried out on four donor controls to estimate intra-individual variation and then ten controls for inter-individual variation to measure assay reproducibility. The G2 assay was then applied to 27 breast cancer patients. Good intrinsic assay reproducibility was observed in the coefficient of variation (CV) data in three out of four controls. Intra-individual variation was similar in three out of four of the donors (4.6 - 5.1%) with one donor showing a higher CV compared with the others (22.9%). Inter-individual variation was calculated at 30.5% for all controls. No significant difference was observed between intra- and inter-individual variation using the variance ratio F-test. A G2 radiosensitivity cut-off of 110 aberrations/100 metaphases was calculated from the controls, and from this 70.4% of breast cancer patients and 7.7% of controls were calculated as G2 radiosensitive. This proportion of G2-sensitive breast cancer patients is the highest recorded in studies to date. It is thought that the G2 radiosensitivity assay is a biomarker of breast cancer predisposition genes of low penetrance, suggesting the presence of these genes in the Irish breast cancer patients used in this study who were recorded as sporadic cases. A larger number of Irish patients would be required to consolidate these findings and be representative of the Irish breast cancer population.

The International Testicular Cancer Linkage Consortium: a clinicopathologic descriptive analysis of 461 familial malignant testicular germ cell tumor kindred

OBJECTIVES

Familial aggregation of testicular germ cell tumor (TGCT) has been reported, but it is unclear if familial TGCT represents a unique entity with distinct clinicopathologic characteristics. Here we describe a collection of familial TGCT cases from an international consortium, in an effort to elucidate any clinical characteristics that are specific to this population.

MATERIALS AND METHODS

Families with >or=2 cases of TGCT enrolled at 18 of the sites participating in the International Testicular Cancer Linkage Consortium were included. We analyzed clinicopathologic characteristics of 985 cases from 461 families.

RESULTS

A majority (88.5%) of families had only 2 cases of TGCT. Men with seminoma (50% of cases) had an older mean age at diagnosis than nonseminoma cases (P = 0.001). Among individuals with a history of cryptorchidism, TGCT was more likely to occur in the ipsilateral testis (kappa = 0.65). Cousin pairs appeared to represent a unique group, with younger age at diagnosis and a higher prevalence of cryptorchidism than other families.

CONCLUSIONS

Clinicopathologic characteristics in these familial TGCT cases were similar to those generally described for nonfamilial cases. However, we observed a unique presentation of familial TGCT among cousin pairs. Additional studies are needed to further explore this observation.

Analysis of the DND1 gene in men with sporadic and familial testicular germ cell tumors

A base substitution in the mouse Dnd1 gene resulting in a truncated Dnd protein has been shown to be responsible for germ cell loss and the development of testicular germ cell tumors (TGCT) in the 129 strain of mice. We investigated the human orthologue of this gene in 263 patients (165 with a family history of TGCT and 98 without) and found a rare heterozygous variant, p. Glu86Ala, in a single case. This variant was not present in control chromosomes (0/4,132). Analysis of the variant in an additional 842 index TGCT cases (269 with a family history of TGCT and 573 without) did not reveal any additional instances. The variant, p. Glu86Ala, is within a known functional domain of DND1 and is highly conserved through evolution. Although the variant may be a rare polymorphism, a change at such a highly conserved residue is characteristic of a disease-causing variant. Whether it is disease-causing or not, mutations in DND1 make, at most, a very small contribution to TGCT susceptibility in adults and adolescents.

RAD51 135G-->C modifies breast cancer risk among BRCA2 mutation carriers: results from a combined analysis of 19 studies

RAD51 is an important component of double-stranded DNA-repair mechanisms that interacts with both BRCA1 and BRCA2. A single-nucleotide polymorphism (SNP) in the 5' untranslated region (UTR) of RAD51, 135G-->C, has been suggested as a possible modifier of breast cancer risk in BRCA1 and BRCA2 mutation carriers. We pooled genotype data for 8,512 female mutation carriers from 19 studies for the RAD51 135G-->C SNP. We found evidence of an increased breast cancer risk in CC homozygotes (hazard ratio [HR] 1.92 [95% confidence interval {CI} 1.25-2.94) but not in heterozygotes (HR 0.95 [95% CI 0.83-1.07]; P=.002, by heterogeneity test with 2 degrees of freedom [df]). When BRCA1 and BRCA2 mutation carriers were analyzed separately, the increased risk was statistically significant only among BRCA2 mutation carriers, in whom we observed HRs of 1.17 (95% CI 0.91-1.51) among heterozygotes and 3.18 (95% CI 1.39-7.27) among rare homozygotes (P=.0007, by heterogeneity test with 2 df). In addition, we determined that the 135G-->C variant affects RAD51 splicing within the 5' UTR. Thus, 135G-->C may modify the risk of breast cancer in BRCA2 mutation carriers by altering the expression of RAD51. RAD51 is the first gene to be reliably identified as a modifier of risk among BRCA1/2 mutation carriers.

Molecular basis for estrogen receptor alpha deficiency in BRCA1-linked breast cancer

BACKGROUND

BRCA1-mutant breast tumors are typically estrogen receptor alpha (ER alpha) negative, whereas most sporadic tumors express wild-type BRCA1 and are ER alpha positive. We examined a possible mechanism for the observed ER alpha-negative phenotype of BRCA1-mutant tumors.

METHODS

We used a breast cancer disease-specific microarray to identify transcripts that were differentially expressed between paraffin-embedded samples of 17 BRCA1-mutant and 14 sporadic breast tumors. We measured the mRNA levels of estrogen receptor 1 (ESR1) (the gene encoding ER alpha), which was differentially expressed in the tumor samples, by quantitative polymerase chain reaction. Regulation of ESR1 mRNA and ER alpha protein expression was assessed in human breast cancer HCC1937 cells that were stably reconstituted with wild-type BRCA1 expression construct and in human breast cancer T47D and MCF-7 cells transiently transfected with BRCA1-specific short-interfering RNA (siRNA). Chromatin immunoprecipitation assays were performed to determine if BRCA1 binds the ESR1 promoter and to identify other interacting proteins. Sensitivity to the antiestrogen drug fulvestrant was examined in T47D and MCF-7 cells transfected with BRCA1-specific siRNA. All statistical tests were two-sided.

RESULTS

Mean ESR1 gene expression was 5.4-fold lower in BRCA1-mutant tumors than in sporadic tumors (95% confidence interval [CI] = 2.6-fold to 40.1-fold, P = .0019). The transcription factor Oct-1 recruited BRCA1 to the ESR1 promoter, and both BRCA1 and Oct-1 were required for ER alpha expression. BRCA1-depleted breast cancer cells expressing exogenous ER alpha were more sensitive to fulvestrant than BRCA1-depleted cells transfected with empty vector (T47D cells, the mean concentration of fulvestrant that inhibited the growth of 40% of the cells [IC40] for empty vector versus ER alpha: >10(-5) versus 8.0 x 10(-9) M [95% CI = 3.1 x 10(-10) to 3.2 x 10(-6) M]; MCF-7 cells, mean IC40 for empty vector versus ER alpha: >10(-5) versus 4.9 x 10(-8) M [95% CI = 2.0 x 10(-9) to 3.9 x 10(-6) M]).

CONCLUSIONS

BRCA1 alters the response of breast cancer cells to antiestrogen therapy by directly modulating ER alpha expression.

Relapsing granulomatous angiitis of the central nervous system in a patient while in remission from Hodgkin lymphoma

We present a patient with granulomatous angiitis of the central nervous system (GANS) and Hodgkin lymphoma. His GANS resolved with treatment for the lymphoma, but then reactivated six months later in the absence of activate lymphoma. He made a full neurological recovery after treatment with reducing oral prednisolone over one year. This case indicates that prolonged use of steroids may be necessary to treat GANS in this setting and that it can run a course independent of the Hodgkin lymphoma.

Genome-wide linkage screen for testicular germ cell tumour susceptibility loci

A family history of disease is a strong risk factor for testicular germ cell tumour (TGCT). In order to identify the location of putative TGCT susceptibility gene(s) we conducted a linkage search in 237 pedigrees with two or more cases of TGCT. One hundred and seventy-nine pedigrees were evaluated genome-wide with an average inter-marker distance of 10 cM. An additional 58 pedigrees were used to more intensively investigate several genomic regions of interest. Genetic linkage analysis was performed with the ALLEGRO software using two model-based parametric analyses and a non-parametric analysis. Six genomic regions on chromosomes 2p23, 3p12, 3q26, 12p13-q21, 18q21-q23 and Xq27 showed heterogeneity LOD (HLOD) scores of greater than 1, with a maximum HLOD of 1.94 at 3q26. Genome-wide simulation studies indicate that the observed number of HLOD peaks greater than one does not differ significantly from that expected by chance. A TGCT locus at Xq27 has been previously reported. Of the 237 pedigrees examined in this study, 66 were previously unstudied at Xq27, no evidence for linkage to this region was observed in this new pedigree set. Overall, the results indicate that no single major locus can account for the majority of the familial aggregation of TGCT, and suggests that multiple susceptibility loci with weak effects contribute to the disease.

The Y deletion gr/gr and susceptibility to testicular germ cell tumor

Testicular germ cell tumor (TGCT) is the most common cancer in young men. Despite a considerable familial component to TGCT risk, no genetic change that confers increased risk has been substantiated to date. The human Y chromosome carries a number of genes specifically involved in male germ cell development, and deletion of the AZFc region at Yq11 is the most common known genetic cause of infertility. Recently, a 1.6-Mb deletion of the Y chromosome that removes part of the AZFc region--known as the "gr/gr" deletion--has been associated with infertility. In epidemiological studies, male infertility has shown an association with TGCT that is out of proportion with what can be explained by tumor effects. Thus, we hypothesized that the gr/gr deletion may be associated with TGCT. Using logistic modeling, we analyzed this deletion in a large series of TGCT cases with and without a family history of TGCT. The gr/gr deletion was present in 3.0% (13/431) of TGCT cases with a family history, 2% (28/1,376) of TGCT cases without a family history, and 1.3% (33/2,599) of unaffected males. Presence of the gr/gr deletion was associated with a twofold increased risk of TGCT (adjusted odds ratio [aOR] 2.1; 95% confidence interval [CI] 1.3-3.6; P = .005) and a threefold increased risk of TGCT among patients with a positive family history (aOR 3.2; 95% CI 1.5-6.7; P = .0027). The gr/gr deletion was more strongly associated with seminoma (aOR 3.0; 95% CI 1.6-5.4; P = .0004) than with nonseminoma TGCT (aOR 1.5; 95% CI 0.72-3.0; P = .29). These data indicate that the Y microdeletion gr/gr is a rare, low-penetrance allele that confers susceptibility to TGCT.

Prediction of BRCA1 status in patients with breast cancer using estrogen receptor and basal phenotype

PURPOSE

To investigate the proportion of breast cancers arising in patients with germ line BRCA1 and BRCA2 mutations expressing basal markers and developing predictive tests for identification of high-risk patients.

EXPERIMENTAL DESIGN

Histopathologic material from 182 tumors in BRCA1 mutation carriers, 63 BRCA2 carriers, and 109 controls, collected as part of the international Breast Cancer Linkage Consortium were immunohistochemically stained for CK14, CK5/6, CK17, epidermal growth factor receptor (EGFR), and osteonectin.

RESULTS

All five basal markers were commoner in BRCA1 tumors than in control tumors (CK14: 61% versus 12%; CK5/6: 58% versus 7%; CK17: 53% versus 10%; osteonectin: 43% versus 19%; EGFR: 67% versus 21%; P < 0.0001 in each case). In a multivariate analysis, CK14, CK5/6, and estrogen receptor (ER) remained significant predictors of BRCA1 carrier status. In contrast, the frequency of basal markers in BRCA2 tumors did not differ significant from controls.

CONCLUSION

The use of cytokeratin staining in combination with ER and morphology provides a more accurate predictor of BRCA1 mutation status than previously available, that may be useful in selecting patients for BRCA1 mutation testing. The high percentage of BRCA1 cases positive for EGFR suggests that specific anti-tyrosine kinase therapy may be of potential benefit in these patients.

Somatic mutations of KIT in familial testicular germ cell tumours

Somatic mutations of the KIT gene have been reported in mast cell diseases and gastrointestinal stromal tumours. Recently, they have also been found in mediastinal and testicular germ cell tumours (TGCTs), particularly in cases with bilateral disease. We screened the KIT coding sequence (except exon 1) for germline mutations in 240 pedigrees with two or more cases of TGCT. No germline mutations were found. Exons 10, 11 and 17 of KIT were examined for somatic mutations in 123 TGCT from 93 multiple-case testicular cancer families. Five somatic mutations were identified; four were missense amino-acid substitutions in exon 17 and one was a 12 bp in-frame deletion in exon 11. Two of seven TGCT from cases with bilateral disease carried KIT mutations compared with three out of 116 unilateral cases (P=0.026). The results indicate that somatic KIT mutations are implicated in the development of a minority of familial as well as sporadic TGCT. They also lend support to the hypothesis that KIT mutations primarily take place during embryogenesis such that primordial germ cells with KIT mutations are distributed to both testes.

Non-Hodgkin lymphoma: an update

Non-Hodgkin lymphoma (NHL) causes many deaths worldwide, and its incidence is increasing. Although some cases are associated with immunodeficiency, autoimmunity, or viral infections, in most cases the causes of NHL are not understood. However, there have been some important advances in our understanding of the development of healthy lymphocytes and the pathogenesis of NHL over the past 10 years. These advances have been accompanied by an improvement in treatment for NHL. Before the late 1990s, the only treatment option available was cytotoxic chemotherapy. In the past 10 years, however, high-dose chemotherapy and autologous stem-cell reconstitution have become established parts of treatment for aggressive lymphoma. Furthermore, monoclonal antibodies have become another therapeutic option. Rituximab (an anti-CD20 monoclonal antibody) is the most advanced monoclonal antibody in clinical trials and has become part of standard treatment for some lymphomas. Rituximab, and many other monoclonal antibodies, continue to be assessed in clinical studies. Monoclonal antibodies can be used alone or in combination with standard-dose or high-dose chemotherapy, and they can also be conjugated to radionuclides to enhance cytotoxicity. Here, we review advances in the treatment of NHL that have occurred over the past 10 years.

Introduction: All Ireland Fatigue Coalition

The first professional meeting and educational symposium of the All Ireland Fatigue Coalition (AIFC) convened in Dublin in September 2002, with an attendance of 350 health professionals who work in cancer research and cancer patient care. The AIFC is a multidisciplinary team of doctors, nurses, and other health care professionals from Ireland, Northern Ireland, and the U.S. whose mission is to champion the proactive management of cancer-related fatigue. The major goals of the symposium were to better understand the status and prevalence of cancer fatigue on the island of Ireland and to learn how to better assess and manage fatigue in cancer patients. An international faculty presented on topics ranging from defining the condition to developing an international protocol implementing a fatigue algorithm.

Predictive testing for BRCA1 and 2 mutations: a male contribution

BACKGROUND

Management strategies for women carrying BRCA1 and 2 mutations are becoming clearer and predictive testing for a known family mutation is commonly undertaken. Implications for men are not as clear and they participate less frequently.

PATIENTS AND METHODS

Twenty-six men from 10 extended families underwent predictive testing. Their motivation, reaction and outcome were studied. Subjects had appropriate pre- and post-test counselling. Informed consent was obtained before predictive testing for known deleterious mutations. DNA analysis followed standard procedures.

RESULTS

Eighteen tested positive and eight negative. Four had adverse psychological reactions and three reneged on their commitments to impart results. The spouse of another man had an adverse psychological reaction to the disclosure of his positive result. Two, already suffering from prostate cancer, were phenocopies and paternal lineage transmission was unexpectedly determined in another. Risk was removed from 33 offspring and confirmed for 56.

CONCLUSIONS

Complex themes associated with genetic testing are confirmed and the spectrum extended. Men appear to understand the importance of participating in this process. Methods of avoiding adverse reactions merit further study along with other aspects of the process.

Herbal ephedra/caffeine for weight loss: a 6-month randomized safety and efficacy trial

OBJECTIVE

To examine long-term safety and efficacy for weight loss of an herbal Ma Huang and Kola nut supplement (90/192 mg/day ephedrine alkaloids/caffeine).

DESIGN

Six-month randomized, double-blind placebo controlled trial.

SUBJECTS

A total of 167 subjects (body mass index (BMI) 31.8+/-4.1 kg/m(2)) randomized to placebo (n=84) or herbal treatment (n=83) at two outpatient weight control research units.

MEASUREMENTS

Primary outcome measurements were changes in blood pressure, heart function and body weight. Secondary variables included body composition and metabolic changes.

RESULTS

By last observation carried forward analysis, herbal vs placebo treatment decreased body weight (-5.3+/-5.0 vs. -2.6+/-3.2 kg, P<0.001), body fat (-4.3+/-3.3 vs. -2.7+/-2.8 kg, P=0.020) and LDL-cholesterol (-8+/-20 vs. 0+/-17 mg/dl, P=0.013), and increased HDL-cholesterol (+2.7+/-5.7 vs. -0.3+/-6.7 mg/dl, P=0.004). Herbal treatment produced small changes in blood pressure variables (+3 to -5 mm Hg, P< or =0.05), and increased heart rate (4+/-9 vs. -3+/-9 bpm, P<0.001), but cardiac arrhythmias were not increased (P>0.05). By self-report, dry mouth (P<0.01), heartburn (P<0.05), and insomnia (P<0.01) were increased and diarrhea decreased (P<0.05). Irritability, nausea, chest pain and palpitations did not differ, nor did numbers of subjects who withdrew.

CONCLUSIONS

In this 6-month placebo-controlled trial, herbal ephedra/caffeine (90/192 mg/day) promoted body weight and body fat reduction and improved blood lipids without significant adverse events.

The NCI-Ireland consortium: a unique international partnership in cancer care

The Ireland-Northern Ireland-National Cancer Institute Cancer Consortium was launched in October of 1999, at a conference in Belfast, Northern Ireland, for the development of cancer programs in Ireland and Northern Ireland, where cancer is a significant cause of mortality and morbidity. Cancer services there have undergone major restructuring as a result of several government reports. Specifically, the National Strategy Document for Cancer proposed that cancer treatment services should be centered around primary care services, regional services, and a national coordinating structure where supra-regional centers would deliver specialist surgery, medical and radiation oncology, rehabilitation, and specialist palliative care. Therefore, this was an opportune time to bring the National Cancer Institute (NCI) on board in a determined effort to redevelop and significantly improve services and outcomes for cancer patients throughout the island. During the NCI All Ireland Cancer Consortium, initial major goals were established as follows: A) To share best available technology and enhance clinical research; B) conduct joint clinical research studies involving people from all jurisdictions; C) sponsor formal training exchanges for Irish and American scholars in cancer programs in partner institutions; D) implement the use of teleconferencing, telesynergy, and other information technology capabilities to facilitate education, and E) consolidate the Cancer Registries of Ireland and Northern Ireland and learn more about cancer incidence and trends on the entire island. In the past year, significant advances have been made in all these areas. Plans are already under way for the second NCI All Ireland Cancer Conference which will be held in late 2002 and feature speakers from Ireland, Northern Ireland, the U.S., and other areas. It will be open to all oncologists, researchers, nurses, students, and other health care professionals interested in learning and enhancing cancer care and research.

Hyperhomocysteinemia and transplant coronary artery disease in cardiac transplant recipients

BACKGROUND

In cardiac transplant recipients, long-term survival may be limited by transplant coronary artery disease (TxCAD). Hyperhomocysteinemia (Hhcy) has been associated with vascular disease and is common in transplant recipients. The objective of this study was to determine the relationship between fasting homocysteine (Hcy) concentrations and TxCAD in a cohort of cardiac transplant recipients.

METHODS

Forty-eight patients more than 5 yr after transplant were recruited from a cohort of 72 consecutive patients with in-depth analysis of homocysteine levels from the Cardiac Transplant Clinic. Early morning fasting blood was obtained, and the plasma separated and frozen within 30 min. Hcy concentrations were determined by high-performance liquid chromatography (HPLC) with pulsed integrated amperometry. Coronary angiograms were reviewed in a blinded fashion. TxCAD was diagnosed, using the most recent angiogram, when a >25% lesion was present anywhere in the coronary tree.

RESULTS

Forty-eight patients transplanted between 1985 and 1994 were studied. The mean Hcy concentration for the cohort was 23.5+/-5.0 micromol/L, all patients had homocysteine levels above the upper range of normal (5-15 micromol/L). Hcy concentrations were significantly higher in patients with angiographic evidence of TxCAD: 25.0+/-5.9 vs. 21.9+/-3.4 micromol/L, p=0.03. This effect persisted when covariates were taken into account using logistic regression analysis.

CONCLUSIONS

Hhcy is associated with TxCAD. Prospective studies are required to confirm this association and to assess the efficacy of Hcy-lowering therapy in this patient population.

Effective progenitor cell mobilization in lymphoproliferative disorders using ifosfamide, epirubicin and etoposide (IEV)

The combination of ifosfamide, epirubicin and etoposide (IEV) is an effective salvage regimen for lymphoproliferative disease. We report our experience with this combination in mobilization of peripheral blood stem cells (PBSC) in patients with relapsed or refractory/high-risk lymphoma. The median time to leukapheresis was 14 days, with 85% of patients commencing PBSC collection in the range of 13-15 days. Mobilization was successful in 26 of 28 patients (93%), who achieved the minimum transplant dose of 2 x 10(6)/kg CD34+ cells in a median of 2 leukaphereses. Overall, the median CD34+ cell yield was 6.94 x 10(6)/kg (range 0.73-27.4). In 15 of 27 patients (54%), the yield was sufficient (> 6 x 10(6)/kg) to permit CD34+ cell selection and/or a second autograft. IEV was given as an inpatient in all cases. Patients were scheduled for discharge after chemotherapy. This was achieved in 71%, with readmission 1 week later for harvest. Therapy was complicated by neutropenic fever in 13 patients and mild nausea. In autografts carried out using IEV-mobilized PBSC (n = 20), the median time to neutrophils > 0.5 x 10(9)/L was 10 days (range 7-13 days), and to platelets > 20 x 10(9)/L was 13 days (range 11-18 days). There was no mobilization- or transplant-related mortality. We conclude that IEV is a safe, predictable and highly effective mobilization regimen in patients with lymphoma.

The pathology of familial breast cancer: histological features of cancers in families not attributable to mutations in BRCA1 or BRCA2

Breast cancers arising in carriers of mutations in the breast cancer susceptibility genes, BRCA1 and BRCA2, differ histologically from each other and from breast cancers unselected for a family history. However, a substantial proportion of families with multiple cases of breast cancer is not attributable to these two genes (non-BRCA1/2 families). We have now characterized the pathology of 82 breast cancers from non-BRCA1/2 families. Breast cancers in non-BRCA1/2 families were of lower grade (P = 0.0018), showed fewer mitoses (P < 0.0001), less nuclear pleomorphism (P = 0.0014), less lymphocytic infiltrate (P < 0.0001), a lesser extent of the tumor with a continuous pushing margin (P = 0.004), a lesser extent of the tumor composed of solid sheets of cells (P = 0.0047), less necrosis (P = 0.002), and wereparison with BRCA2 tumors, non-BRCA1/2 tumors were lower grade (P = 0.017) and exhibited less pleomorphism (P = 0.01) and more tubule formation (P = 0.05). In comparison with control breast cancers unselected for a family history of the disease, non-BRCA1/2 tumors were of significantly lower grade (P = 0.001), showed less pleomorphism (P = 0.0002), and had a lower mitotic count (P = 0.003). The results indicate that non-BRCA1/2 breast cancers differ histologically from both BRCA1 and BRCA2 breast cancers and are overall of lower grade. They also suggest that non-BRCA1/2 breast cancers differ from nonfamilial breast cancers, but these differences may be attributable to various types of bias.

Localization to Xq27 of a susceptibility gene for testicular germ-cell tumours

Testicular germ-cell tumours (TGCT) affect 1 in 500 men and are the most common cancer in males aged 15-40 in Western European populations. The incidence of TGCT has risen dramatically over the last century. Known risk factors for TGCT include a history of undescended testis (UDT), testicular dysgenesis, infertility, previously diagnosed TGCT (ref. 7) and a family history of the disease. Brothers of men with TGCT have an 8-10-fold risk of developing TGCT (refs 8,9), whereas the relative risk to fathers and sons is fourfold (ref. 9). This familial relative risk is much higher than that for most other types of cancer. We have collected samples from 134 families with two or more cases of TGCT, 87 of which are affected sibpairs. A genome-wide linkage search yielded a heterogeneity lod (hlod) score of 2.01 on chromosome Xq27 using all families compatible with X inheritance. We obtained a hlod score of 4.7 from families with at least one bilateral case, corresponding to a genome-wide significance level of P=0.034. The proportion of families with UDT linked to this locus was 73% compared with 26% of families without UDT (P=0.03). Our results provide evidence for a TGCT susceptibility gene on chromosome Xq27 that may also predispose to UDT.

Correlation between total homocysteine and cyclosporine concentrations in cardiac transplant recipients

Increased circulating total homocysteine (tHcy) has been implicated as an independent risk factor for atherosclerotic disease. In cardiac transplant patients, accelerated coronary atherosclerosis is an important cause of late allograft failure; however, studies of tHcy in this at-risk group are limited. We sampled a cohort of 72 subjects 3.95+/-3.14 (mean +/- SD) years after transplantation and found that all had tHcy concentrations above our upper reference limit (15.0 micromol/L). The mean tHcy in the transplant group (25.4+/-7.1 micromol/L) was significantly greater than in our reference group (9.0+/-4.3 micromol/L; n = 457; P <0.001). We also examined the effect of age, gender, time since transplant, serum folate and cobalamin, total protein, urate, creatinine, albumin, and trough whole blood cyclosporine concentrations. In a multiple linear regression model, only creatinine (mean 144+/-52 micromol/L; P = 0.021) and trough cyclosporine concentrations (191+/-163 microg/L; P = 0.015) were independent positive predictors of tHcy, whereas serum folate (8.35+/-7.43 nmol/L; P = 0.018) and time since transplant (P = 0.049) were significant negative predictors. We conclude that hyperhomocysteinemia is a common characteristic of cardiac transplant recipients. Our analysis suggests that folate and renal glomerular dysfunction are important contributory factors; however, whole blood cyclosporine concentrations may also predict the degree of hyperhomocysteinemia in this population and therefore influence interpretation of any apparent response to treatment.

Multifactorial analysis of differences between sporadic breast cancers and cancers involving BRCA1 and BRCA2 mutations

BACKGROUND

We have previously demonstrated that breast cancers associated with inherited BRCA1 and BRCA2 gene mutations differ from each other in their histopathologic appearances and that each of these types differs from breast cancers in patients unselected for family history (i.e., sporadic cancers). We have now conducted a more detailed examination of cytologic and architectural features of these tumors.

METHODS

Specimens of tumor tissue (5-microm-thick sections) were examined independently by two pathologists, who were unaware of the case or control subject status, for the presence of cell mitosis, lymphocytic infiltration, continuous pushing margins, and solid sheets of cancer cells; cell nuclei, cell nucleoli, cell necrosis, and cell borders were also evaluated. The resulting data were combined with previously available information on tumor type and tumor grade and further evaluated by multifactorial analysis. All statistical tests are two-sided.

RESULTS

Cancers associated with BRCA1 mutations exhibited higher mitotic counts (P = .001), a greater proportion of the tumor with a continuous pushing margin (P<.0001), and more lymphocytic infiltration (P = .002) than sporadic (i.e., control) cancers. Cancers associated with BRCA2 mutations exhibited a higher score for tubule formation (fewer tubules) (P = .0002), a higher proportion of the tumor perimeter with a continuous pushing margin (P<.0001), and a lower mitotic count (P = .003) than control cancers.

CONCLUSIONS

Our study has identified key features of the histologic phenotypes of breast cancers in carriers of mutant BRCA1 and BRCA2 genes. This information may improve the classification of breast cancers in individuals with a family history of the disease and may ultimately aid in the clinical management of patients.

Pseudo-Cushing's syndrome in human immunodeficiency virus-infected patients

To our knowledge, an association between human immunodeficiency virus infection and pseudo-Cushing's syndrome has not previously been described. We describe four HIV-infected patients with pseudo-Cushing's syndrome, characterized by striking dorsocervical and submandibular fat accumulation and central obesity. In each case, cortisol levels were either normal or suppressed adequately with administration of dexamethasone, excluding the diagnosis of true Cushing's syndrome. Immune function and weight improved significantly preceding the development of pseudo-Cushing's syndrome. Three of the four patients were taking a common protease inhibitor at the onset of symptoms, and the fourth reported the exacerbation of his symptoms with the addition of a protease inhibitor. The observed characteristic pattern of fat deposition may be attributable to a specific effect of new antiretroviral therapies or may relate to recovery independent of medication usage. Distinguishing between pseudo-Cushing's syndrome and true Cushing's syndrome is critical for preventing the unnecessary and potentially harmful treatment of such patients. Further research into the mechanisms of this novel phenomenon is needed.

Small cell carcinoma of the oesophagus

Small cell carcinoma of the oesophagus is an uncommon malignancy. Only 272 cases have been reported to date. Inconsistency in therapeutic approaches reflects the paucity of individual experience and the unsatisfactory response to current management strategies. We report 11 cases drawn from a series of 1012 cases of oesophageal malignancy and perform a statistical analysis on treatment and survival data of 189 cases drawn from the world literature. Small cell carcinoma of the oesophagus was seen to have an incidence of 1%. Seven of 11 patients were female. A variety of therapeutic modalities were employed, and the median survival was 6.6 months. Statistical analysis of these and worldwide data showed a significant survival advantage for patients who received multimodality therapy.

Cancer risks in two large breast cancer families linked to BRCA2 on chromosome 13q12-13

The penetrance of the BRCA2 gene on chromosome 13q12-13 has been estimated in two large, systematically ascertained, linked families, by use of a maximum-likelihood method to incorporate both cancer-incidence data and 13q marker typings in the families. The cumulative risk of breast cancer in female gene carriers was estimated to be 59.8% by age 50 years (95% confidence interval [95% CI] 25.9%-78.5%) and 79.5% by age 70 years (95% CI 28.9%-97.5%). The cumulative risk of breast cancer in male carriers was estimated to be 6.3% (95% CI 1.4%-25.6%) by age 70 years. There was no evidence of any risk difference between the two families. These results indicate that the lifetime breast cancer risk in BRCA2 carriers, for at least a subset of mutations, is comparable to that for BRCA1. A significant excess of ovarian cancer in gene carriers was observed (relative risk 17.69, based on three cases), but the absolute risk of ovarian cancer was less than that reported for BRCA1. Significant excesses of laryngeal cancer (relative risk 7.67, based on two possible carriers) and prostate cancer (relative risk 2.89, based on five possible carriers) were also observed. One case of ocular melanoma, as well as a second eye cancer of unspecified histology, occurred in obligate gene carriers.

Myelodysplasia and acute myeloid leukaemia following adjuvant chemotherapy for breast cancer using mitoxantrone and methotrexate with or without mitomycin

BACKGROUND

Secondary acute myeloid leukaemia/myelodysplasia (t-AML, t-MDS) may occur following adjuvant chemotherapy for breast cancer and has been most frequently associated with alkylating agents. This complication is now being associated with an expanding list of chemotherapeutic agents including topoisomerase II poisons. Mitoxantrone is an agent with potential to cause t-AML and t-MDS and which is being used increasingly in the treatment of breast cancer.

PATIENTS AND METHODS

Fifty-nine patients who received mitoxantrone as part of adjuvant chemotherapy for breast cancer between 1986 and 1992 were studied to determine the incidence of t-AML and t-MDS.

RESULTS

With a median follow-up of 72 months, 2 cases of t-AML and 1 of t-MDS have occurred.

CONCLUSIONS

This 5% incidence of t-AML and t-MDS is high and likely related to mitoxantrone. Whereas this agent is effective and has acceptable toxicity in advanced disease, its incorporation into adjuvant treatment regimens cannot be recommended based on this experience.

Elevated platelet-derived microparticle levels during unstable angina

OBJECTIVE

To use fluorescent-activated flow cytometry coupled with activation-dependent and -independent platelet-specific monoclonal antibodies in a pilot study to assess the degree and time course of platelet activation events in patients presenting within 24 h of onset of Canadian Cardiovascular Society class 4 angina.

BACKGROUND

Although activated platelets play a key role in the pathogenesis of unstable angina, the development of simple assays to quantify platelet activation events directly is lacking.

METHODS

Blood samples were drawn from six unstable angina patients from the coronary care every 4 h over a 24 h period into a fixative and analyzed the following day. All patients were on acetylsalicylic acid and heparin. Comparisons were made with six healthy, medication-free volunteers. Platelets were defined by flow cytometry as positive for fluorochrome-labelled monoclonal antibody to glycoprotein Ib (AP1) and within the single intact platelet window defined by scatter characteristics. The presence of the fluorochrome-labelled activation-specific monoclonal antibody (KC4.1 for anti-P-selectin, PAC-1 for activated glycoprotein IIb/IIIa) was used to determine the percentage of activated platelets. Platelet activation-dependent microparticles were identified by gating on AP1-positive events and defining microparticles (percentage of total platelet events) as being smaller (forward size scatter) than single intact platelets.

RESULTS

There was a marked, sixfold increase in microparticle generation (17 +/- 7% versus 2.8 +/- 1.4%) in the unstable angina patients (P = 0.001) compared with healthy volunteers. Further assessment of six coronary care unit patients with nonischemic cardiac disorders demonstrated a highly variable intermediate level of microparticle generation (11 +/- 7%). No differences in activated glycoprotein IIb/IIIa expression were noted for the various groups and P-selectin expression was lower in the unstable angina patients (6 +/- 2% versus 12 +/- 3%, (P = 0.007).

CONCLUSIONS

This pilot study suggests that measuring circulating platelet microparticle levels is a simple yet useful parameter for the assessment of platelet activation in unstable angina compared with activation markers on intact whole platelets. Despite antiplatelet and antithrombin therapy, significant platelet activation occurred in these patients over the initial 24 h. Flow cytometry may be a useful tool in assessing the efficacy of newer therapeutic modalities.

Reductions in muscle sympathetic nerve activity after long-term metoprolol for dilated cardiomyopathy: preliminary observations

OBJECTIVE

To determine whether efferent muscle sympathetic nerve activity diminishes in subjects with dilated cardiomyopathy who improve after long term treatment with metoprolol.

METHODS

Microneurographic, echocardiographic, plethysmographic, and neurohumoral data were obtained immediately before and 20 months after the addition of beta blockade in seven subjects with idiopathic dilated cardiomyopathy with clinical deterioration despite conventional treatment.

RESULTS

Six subjects (three men, three women, aged 24-62 years) were restudied after a mean (SEM) of 20 (2.4) months treatment with metoprolol (45.8 (2.6) mg/d). Long term treatment was associated with decreases in left ventricular end diastolic and end systolic diameter (P < 0.005), left ventricular mass index (P < 0.05), and atrial natriuretic factor (P < 0.05), and increases in fractional shortening (P < 0.05) and mean blood pressure (P < 0.05). There was a 50% reduction in peroneal muscle sympathetic nerve activity (from 49.2 (10.1) to 24.5 (4.7) bursts/min; (P < 0.005) and a 62% decrease in calf vascular resistance (from 56.2 (4.4) to 21.2 (5.7) units; P < 0.005). This reduction in pulse synchronous nerve activity was not simply a function of bradycardia (heart rate fell from 94.2 (4.6) to 62.8 (5.7) beats/min; P < 0.005) since muscle sympathetic burst incidence also decreased (from 51 (8.7) to 37.5 (5.2) bursts/100 heart beats; P < 0.05). Similar haemodynamic improvement was observed in the seventh subject, who was switched to sotalol 200 mg/d and restudied after 20 months, but burst frequency was 50% higher and calf vascular resistance 93% higher.

CONCLUSIONS

Muscle sympathetic nerve activity and calf vascular resistance decrease in patients with dilated cardiomyopathy who improve after long term treatment with metoprolol. Inhibition of central sympathetic outflow may be one mechanism by which metoprolol benefits such subjects.

Office management of osteoporosis: a guide for the primary care provider

Osteoporosis is greatly increasing in prevalence as the population ages. Postmenopausal women are at particularly high risk. I have reviewed the risk factors for osteoporosis, the office evaluation, laboratory and radiologic testing, and available treatment of osteoporosis. Adequate calcium and vitamin D intake is important in prevention and treatment. Estrogen replacement is the treatment of choice for the menopausal women who has or is at risk for osteoporosis, but several alternatives are available. These drugs prevent bone loss but cannot restore lost bone to any significant degree. Until effective means of restoring normal bone are discovered, increasing peak bone mass in adolescents and young women with the hope of preventing osteoporosis may be the most important intervention.

Abnormalities in intramyocardial arteries detected in cardiac transplant biopsy specimens and lack of correlation with abnormal intracoronary ultrasound or endothelial dysfunction in large epicardial coronary arteries

OBJECTIVES

We sought to determine whether abnormalities in small intramyocardial vessels could be detected on routine cardiac transplant biopsy specimens and whether these features correlate with intimal thickening by intracoronary ultrasound and endothelial dysfunction in large epicardial vessels.

BACKGROUND

Variability in clinical presentation of allograft vasculopathy suggests differential involvement of large and small vessels. Intracoronary ultrasound and endothelial function studies detect large-vessel abnormalities but may not reflect changes in small intramyocardial arteries. The latter could be detected in routine cardiac biopsy specimens by histologic and immunohistochemical studies.

METHODS

Thirty-nine cardiac transplant recipients underwent intracoronary ultrasound and acetylcholine studies 5 to 7 days after endomyocardial biopsy. Biopsy tissue was evaluated for coronary artery endothelial plumping and intimal thickening and increased immunostaining for fibronectin, tumor necrosis factor-alpha and receptor for hyaluronan-mediated motility. Large-vessel disease was assessed by calculating an average intimal index from intracoronary ultrasound of the left anterior descending coronary artery. Endothelial function was determined by quantitative coronary analysis after acetylcholine challenge.

RESULTS

Coronary arteries were found in the biopsy tissue of 30 (76%) of the 39 patients who formed the study group. Fourteen of 30 patients had abnormal histologic findings. Immunohistochemical analysis for fibronectin, possible in 20 of 30 patients, was positive in 14 (70%) of 20 and correlated with abnormal histologic findings (p = 0.01). Immunostaining was positive for tumor necrosis factor-alpha and receptor for hyaluronan-mediated motility in 12 (40%) and 13 (43%) of 30 patients, respectively. All patients had intimal thickening by intracoronary ultrasound, but intimal index did not correlate significantly with small-artery disease by histologic or immunohistochemical analysis. Large-vessel endothelial dysfunction in 13 patients (43%) did not correlate with either abnormal ultrasound findings or small-vessel disease.

CONCLUSIONS

Intramyocardial arteries are readily observed in biopsy specimens from cardiac transplant recipients and provide useful information about allograft vasculopathy. Lack of correlation between intramyocardial and epicardial vessel disease suggests discordant progression of allograft vasculopathy.

Atheroembolism in an endomyocardial biopsy from a cardiac transplant recipient after coronary angioplasty

A case of a coronary atheroembolism after coronary angioplasty was detected by routine myocardial biopsy six years after cardiac transplant. The patient had had three balloon angioplasties within a five week interval for symptomatic accelerated coronary artery disease. Histological examination clearly identified atheromatous debris in a small intramyocardial artery with a secondary inflammatory response. This complication of angioplasty has been identified at necropsy in association with new myocardial infarction. It is unusual to identify this complication in a survivor, and in a case in which there was no clinical evidence of myocardial infarction. Myocardial biopsy samples a relatively small amount of myocardium, and this case suggests that coronary atheroembolism may not be an uncommon complication of angioplasty.

Consistent loss of the wild type allele in breast cancers from a family linked to the BRCA2 gene on chromosome 13q12-13

A small proportion of breast cancer is attributable to the inheritance of dominant, high penetrance susceptibility genes. One of these genes, BRCA2, has recently been localised by genetic linkage analysis to chromosome 13q12-13. This is a region known to exhibit loss of heterozygosity in 20-40% sporadic breast cancers. In this study, we have examined cancers from a family showing strong evidence of linkage to BRCA2. LOH was seen in seven out of eight informative cancers. In all cases the allele lost was the wild type allele that does not segregate with the disease in the family. The data suggest that both alleles of BRCA2 are inactivated in cancers, the pattern expected of a recessive oncogene or tumour suppressor gene.

Malignant lymphoma of the epididymis. A case report of bilateral involvement by a follicular large cell lymphoma

BACKGROUND

Malignant lymphoma of the testis involves the adjacent epididymis in approximately 60% of cases, but isolated epididymal lymphoma is rare.

METHODS

The file of a 34-year-old man was reviewed, and the biopsy material was studied by conventional morphology, immunohistochemistry, and polymerase chain reaction.

RESULTS

The patient presented with painless bilateral epididymal enlargement. Sequential bilateral epididymal biopsies revealed follicular lymphoproliferation with minimal involvement of one testis. Immunoglobulin M antibodies to the Coxsackie B4 virus were increased, and the lesions were interpreted as an atypical reactive process. Chemotherapy was not pursued. Four years after presentation, there was no evidence of local disease, but a 3-cm lesion involving the skin of the forehead developed. An excision biopsy revealed a large cell follicular lymphoma with features resembling the epididymal lesion. Analysis by polymerase chain reaction revealed a t(14-18) translocation in skin and epididymal lesions confirming that the epididymal lesions were also lymphomatous. Staging revealed no other site of disease. To date, the patient, who was treated with methotrexate chemotherapy, remains well 28 months after treatment.

CONCLUSIONS

Most lymphomas of the testis and epididymis occur in older men, have an intermediate or high grade, diffuse histology, disseminate early, and follow an aggressive clinical course. In contrast, this case is similar to the occasional reports of pseudolymphoma and follicular lymphoma that occur in younger men, are confined largely to the testis and epididymis, and have a good prognosis.

Graded exercise testing following thrombolytic therapy for acute myocardial infarction: the importance of timing and infarct location. TPAT Study Group

OBJECTIVES

To determine the influence of timing, infarct location and thrombolytic therapy on the electrocardiographic (ECG) response to exercise testing following acute myocardial infarction.

DESIGN

Maximal treadmill exercise testing was performed on postinfarction day 8 and repeated on day 90 as part of a previously reported double-blind, placebo controlled study of recombinant tissue plasminogen activator (rt-PA) in acute myocardial infarction in which left ventricular function was the primary end-point. Patients were systematically evaluated for left ventricular function, myocardial perfusion and coronary anatomy.

SETTING

Ten collaborating community and academic hospitals.

PATIENTS

One hundred and fifteen patients, aged 20 to 75 years, with ischemic chest pain 30 mins or longer and ST elevation on ECG. Patients with cardiogenic shock, left bundle branch block, prior aortocoronary bypass surgery, recent percutaneous transluminal coronary angioplasty or standard contraindications to thrombolytic therapy were excluded.

MAIN RESULTS

The analysis is confined to the 70 patients who underwent both exercise tests without intercurrent coronary revascularization. Peak rate-pressure product was greater on day 90 than on day 8 (mean difference +/- SE 2.2 +/- 0.6 x 10(3), P = 0.001), whereas 65% of patients had 1 mm or greater of exercise-induced ST shift on day 8 compared with 47% on day 90 (P = 0.025). Patients following anterior compared with inferior infarction were more likely to have exercise-induced ST elevation (54% versus 21%, P = 0.012) but less likely to have ST depression (29% versus 63%, P = 0.017) on day 8; results were directionally similar on day 90. Treatment with rt-PA, compared with placebo, did not influence exercise performance, the ECG response to exercise or the extent of inducible ischemia on thallium scintigraphy.

CONCLUSIONS

Timing and infarct location are important modifiers of the ECG response to exercise testing following myocardial infarction. Thrombolytic therapy in these uncomplicated patients did not influence inducible ischemia.

Effects of chronic lard feeding on sympathetic nervous system activity in the rat

The level of sympathetic nervous system (SNS) activity in obesity is controversial, with reports claiming either increased or decreased SNS activity. The following studies examined SNS activity in a dietary form of obesity, ingestion of a lard-enriched diet for 4 wk. Plasma norepinephrine (NE) levels were 61% higher in rats fed the lard-enriched diet than in chow-fed controls at 20 degrees C (200 +/- 24 pg/ml vs. 124 +/- 6, P < 0.005) and remained elevated after 1 h of cold exposure (4 degrees C). [3H]NE turnover was markedly increased in heart, but not in interscapular brown adipose tissue (IBAT), kidney, liver, skeletal muscle, or spleen of rats fed the high-fat diet. By contrast, ingestion of a diet similarly enriched with sucrose raised rates of [3H]NE turnover in IBAT as well as in heart. Thus chronic ingestion of a lard-enriched diet induces region-specific stimulation of SNS activity that is greater in heart than in IBAT. Whereas the absence of an SNS response to lard in IBAT may contribute to weight gain in these animals, activation of cardiac sympathetic nerves may promote development of hypertension in this model of obesity.

A metastatic neuroendocrine anaplastic small cell tumor in a patient with multiple endocrine neoplasia type 1 syndrome. Assessment of disease status and response to doxorubicin, cyclophosphamide, etoposide chemotherapy through scintigraphic imaging with 111In-pentetreotide

Extrapulmonary small cell and small cell neuroendocrine tumors of unknown primary site are, in general, aggressive neoplasms with a short median survival. Like small cell lung cancer (SCLC), they often are responsive to chemotherapy and radiotherapy. Small cell lung cancer and well differentiated neuroendocrine carcinomas of the gastrointestinal tract and pancreas tend to express somatostatin receptors. These tumors may be localized in patients by scintigraphic imaging using radiolabeled somatostatin analogues. A patient with anaplastic neuroendocrine small cell tumor arising on a background of multiple endocrine neoplasia type 1 syndrome is reported. The patient had a known large pancreatic gastrinoma and previously treated parathyroid adenopathy. At presentation, there was small cell cancer throughout the liver and skeleton. Imaging with a radiolabeled somatostatin analogue, 111In-pentetreotide (Mallinckrodt Medical B. V., Petten, Holland), revealed all sites of disease detected by routine biochemical and radiologic methods. After six cycles of chemotherapy with doxorubicin, cyclophosphamide, and etoposide, there was almost complete clearance of the metastatic disease. 111In-pentetreotide scintigraphy revealed uptake consistent with small areas of residual disease in the liver, the abdomen (in mesenteric lymph nodes), and posterior thorax (in a rib). The primary gastrinoma present before the onset of the anaplastic small cell cancer showed no evidence of response to the treatment. The patient remained well for 1 year and then relapsed with brain, lung, liver, and skeletal metastases. Despite an initial response to salvage radiotherapy and chemotherapy with carboplatin and dacarbazine, the patient died 6 months later.

Soft tissue and visceral sarcomas in Irish patients. Interim analysis of data obtained by the Dublin Soft Tissue Tumour Panel

The Dublin Soft Tissue Sarcoma Panel was established in 1989 with a view to achieving a unified approach to diagnosis and management of soft tissue and visceral sarcomas. This interim report presents data on 265 prospectively-evaluated patients and on a separate retrospective series of 126 patients. The patients in the prospective series were treated by 93 different surgical and medical specialists. Tumours presented in all anatomic sites and ranged in size from 0.2 to 60 cm. Leiomyosarcoma was the commonest tumour type. Eighty-nine tumours were inoperable at clinical presentation. There was a consensus panel diagnosis in over 90%, non-neoplastic reactive lesions and primitive round cell tumours being the most difficult cases diagnostically. Management, including onward referral for chemotherapy or radiation therapy, was inconsistent. The 2-year survival figures were: 43% (1989-91) and 37% (1980-88). These findings should provide a basis for the evaluation of coherent treatment strategies for Irish sarcoma patients.

Concentrations of adipsin in blood and rates of adipsin secretion by adipose tissue in humans with normal, elevated and diminished adipose tissue mass

Adipsin, which is identical to complement factor D, is synthesized by fat cells, circulates in the bloodstream and is profoundly deficient in mice with genetic and hypothalamic obesity. With the recent cloning of human adipsin, a quantitative human immunoassay has been developed. In the present study, we measured adipsin blood concentrations in humans with increased and decreased adipose stores as well as adipsin secretion by adipose tissue obtained from lean and obese individuals. The results demonstrate that adipsin is released by human adipose tissue fragments as has previously been shown in mice, and that, in contrast to obese mice, blood adipsin concentrations were not reduced in the obese humans tested in this study. We also observed that blood adipsin concentrations can vary as a function of feeding or adiposity, in that they tend to be mildly elevated in obese individuals or mildly reduced in individuals with total lipo-atrophy, cachexia related to AIDS and anorexia nervosa. Thus, the circulating concentration of adipsin tends to correlate positively with degree of adiposity. Clearly, no deficiency in blood adipsin concentrations or adipsin secretion by adipose tissue was observed in the obese individuals studied.

Bacteraemia in neutropenic patients

Empirical antibiotic therapy in febrile neutropenic patients should reflect local patterns of microbial isolates and antibiotic resistance. The aim of this study was to review blood culture isolates and antibiotic resistance from neutropenic cancer patients over a four year period as a guide to empiric antimicrobial therapy. All positive blood culture isolates from a mixed haematology/oncology unit between 1988 and 1991 were evaluated retrospectively. Episodes of bacteraemia rose from 9% in 1988 to 13.7% in 1991. Gram-positive organisms accounted for between 61.3% and 72.7% in each of the four years. Isolates of Gram-negative organisms were between 23.6% and 31.5% of which a significant proportion are due to a heterogeneous group of hydrophilic, non-fermentative organisms. Fungal blood culture isolates accounted for between 3% and 4% each year. All Gram positive isolates were sensitive to vancomycin. Piperacillin was the least active B-lactam antibiotic and tobramycin the least active aminoglycoside reflecting the widespread usage of these agents in the unit. In conclusion, bacteraemic episodes are increasing in this patient population and are mainly due to Gram-positive organisms probably as a result of the extensive use of surgically implanted venous access devices.