General practitioner screening for melanoma: sensitivity, specificity, and effect of training

OBJECTIVE

To measure the performance of trained and untrained general practitioners (GPs) in screening men and women aged 50 or more for melanomas.

METHODS

GPs trained in melanoma diagnosis, untrained GPs, and skin cancer specialists examined groups of volunteers, each of which included a small number of subjects with prediagnosed suspicious pigmented lesions (SPLs) that were subsequently excised for histopathological examination.

RESULTS

Trained and untrained GPs achieved mean sensitivities of 0.73 and 0.71, and mean predictive values of 0.40 and 0.37, respectively, for the detection of prediagnosed SPLs. When the SPLs had been excised and examined histopathologically, reanalysis showed mean sensitivities of 0.98 and 0.95, mean specificities of 0.52 and 0.49, and mean positive predictive values of 0.24 and 0.22 for the detection of subjects with melanomas by trained and untrained GPs respectively. Trained GPs were significantly better than untrained GPs at diagnosing as melanomas SPLs that subsequently proved to be melanomas (p = 0.04).

CONCLUSIONS

GPs in this study achieved high sensitivities in screening older Australian men and women for melanomas, but at the cost of low specificities and positive predictive values. Training in melanoma diagnosis had no significant effect on sensitivity, specificity, and positive predictive value for screening. Data from the study were tested in a model of population screening for melanomas, and costs per life year saved for men aged 50-70 ranged from $A11,852 to $A40,259 depending upon the screening interval and whether the GPs excised the SPLs diagnosed, or referred all patients to skin cancer specialists; this would be as cost effective as cervical cancer screening.

An analysis of testosterone implants for androgen replacement therapy

OBJECTIVE

To review 13 years of experience using fused crystalline testosterone implants for androgen replacement therapy in order to identify pattern of usage (including continuation rates) and adverse events emerging during therapy and factors associated with adverse events including implant extrusions.

DESIGN

Retrospective review of prospectively collected data on characteristics of patients and implant procedures performed as well as adverse events reported during routine follow-up.

PATIENTS

Over 13 years 973 implant procedures using fused crystalline testosterone implants were performed in 221 men.

MEASUREMENTS

Continuation rates and adverse events such as extrusions, bleeding, infection or others were recorded and analysed in relationship to characteristics of the patient and the implant procedure performed.

RESULTS

Overall rate of adverse events (108/73, 11.1%) was significantly related to increased numbers of implants (4.2 +/- 0.1 vs 4.0 +/- 0.03, P = 0.031) and higher levels of physical activity at work (P = 0.030). The most common adverse effect was extrusion (83/973, 8.5%) which was related to occupational classification (P = 0.033) and increasing work activity (P = 0.044) and occurred more frequently than by chance in multiple (16 vs 3.3 expected) rather than single (65 vs 76.1 expected) episodes. Bleeding (22/973, 2.3%) was significantly associated with an increased number of implants (4.5 +/- 0.2 vs 4.0 +/- 0.03, P = 0.020) but even in the worst cases (3/22) it was of minor clinical importance. Infection was rare (6/973, 0.6%) but occurred more among thinner men. The overall continuation rate was 92.7% increasing from 86% after the first implantation to > 99% after the tenth implant.

CONCLUSIONS

This study demonstrates the very satisfactory clinical acceptability of testosterone pellet implants for androgen replacement therapy within a single unit with experienced operators. The only regular adverse effect is extrusion, which may be related to mechanical factors such as habitual work activity but also possibly procedural factors. Other adverse effects such as bleeding, infection and fibrosis were rare. An improved method of implant delivery would enhance this old but durable technology.

Allogeneic blood stem cell transplantation: considerations for donors

Allogeneic transplantation of cytokine-mobilized peripheral blood stem cells (PBSCs) is now being increasingly performed, but safety considerations for hematologically normal PBSC donors have not been fully addressed. Progenitors are generally mobilized for collection from normal donors using recombinant human granulocyte colony-stimulating factor (rhG-CSF). Although the short-term safety profile of rhG-CSF seems acceptable, experience remains limited and its optimal dose and schedule have not been defined. Minimal data exist regarding long-term safety of rhG-CSF, primarily derived from experience in patients with chronic neutropenia or cancer. An "ad hoc" workshop was recently convened among a group of investigators actively involved in the field of allogeneic stem cell transplantation to discuss the safety issues pertaining to normal PBSC donors. There was agreement on the following points: (1) On the basis of available data, it appears that rhG-CSF treatment and PBSC collection have an acceptable short-term safety profile in normal donors. However, the need for continued safety monitoring was recognized. (2) rhG-CSF doses up to 10 microg/kg/d show a consistent dose-response relationship with the mobilization (and collection) of CD34+ progenitor cells, and this dose is acceptable for routine clinical use. Whether higher doses are superior (or cost effective) remains to be determined, and they may produce more severe side effects. The potential risks of marked leukocytosis (arbitrarily defined as a leukocyte count of more than 70 x 10(9)/L) have been a concern, and rhG-CSF dose reduction is performed by many centers to maintain leukocyte counts below this level. (3) Transient post donation cytopenias, involving granulocytes, lymphocytes, and platelets, may occur and are at least partly related to the leukapheresis procedure. These are generally asymptomatic and self-limited; follow-up blood counts are not necessarily required. Reinfusion of autologous platelet-rich plasma should be considered for donors with expected postdonation thrombocytopenia (platelet count < 80 to 100 x 10(9)/L). (4) Donors should meet the eligibility criteria which apply to donors of apheresis platelets, with the exception that pediatric donors may also be considered. Any deviation from these criteria should have supporting documentation. There is insufficient information at this time to clearly establish definite contraindications for PBSC collection in a hematologically normal donor. Potential contraindications include the presence of inflammatory, autoimmune, or rheumatologic disorders, as well as atherosclerotic or cerebrovascular disease. (5) The creation of an International PBSC Donor Registry is desirable to facilitate monitoring the long-term effects of the procedure. Individual institutions or donor centers are encouraged to establish their own PBSC donor follow-up system, preferably with a standardized approach to data collection.

Intravesical morphine analgesia after bladder surgery

PURPOSE

A recent demonstration of peripheral opioid receptors suggested the possibility of delivering morphine locally into the bladder after reimplantation for ameliorating the discomfort of postoperative bladder irritation with spasms. Since we do not use bladder drainage after reimplantation, dripping a morphine solution into the bladder permits contact with the urothelium between voidings. A pilot trial using an arbitrary concentration was subjectively beneficial for treating these patients postoperatively. We now report a prospective randomized study evaluating the effectiveness and dosage of various concentrations of intravesical morphine infusions.

MATERIALS AND METHODS

A total of 52 children undergoing ureteral reimplantation was randomized to receive 1 of 3 concentrations of intravesical morphine (0.05, 0.375 or 0.5 mg./ml.). A small feeding tube remained in the bladder to drip a continuous infusion postoperatively. Subsequent postoperative pain was treated with meperidine, acetaminophen and codeine, and/or a belladonna and opium suppository. During each shift a nurse assisted the child in assessing pain using a Baker-Wong faces scale. Bladder infusion was discontinued after day 3 postoperatively and plasma morphine levels were measured on the first morning postoperatively. Kruskal-Wallis and paired t tests were used to evaluate significance.

RESULTS

Patients reported greater pain in the group infused with 0.05 mg./ml. on 4 of 6 shifts on the first 2 days postoperatively. No difference was noted on postoperative day 3. Plasma morphine was undetectable by high pressure liquid chromatography.

CONCLUSIONS

This study offers objective evidence that bladder morphine infusion is effective for ameliorating postoperative pain in the first 48 hours after intravesical ureteral reimplantation. The dose given today is 0.5 mg./ml. delivered at 0.04 ml./kg. per hour.

Pharmacokinetics and pharmacodynamics of nandrolone esters in oil vehicle: effects of ester, injection site and injection volume

We studied healthy men who underwent blood sampling for plasma nandrolone, testosterone and inhibin measurements before and for 32 days after a single i.m. injection of 100 mg of nandrolone ester in arachis oil. Twenty-three men were randomized into groups receiving nandrolone phenylpropionate (group 1, n = 7) or nandrolone decanoate (group 2, n = 6) injected into the gluteal muscle in 4 ml of arachis oil vehicle or nandrolone decanoate in 1 ml of arachis oil vehicle injected into either the gluteal (group 3, n = 5) or deltoid (group 4, n = 5) muscles. Plasma nandrolone, testosterone and inhibin concentrations were analyzed by a mixed-effects indirect response model. Plasma nandrolone concentrations were influenced (P < .001) by different esters and injection sites, with higher and earlier peaks with the phenylpropionate ester, compared with the decanoate ester. After nandrolone decanoate injection, the highest bioavailability and peak nandrolone levels were observed with the 1-ml gluteal injection. Plasma testosterone concentrations were also influenced (P < .001) by the ester and injection site, with the most rapid, but briefest, suppression being due to the phenylpropionate ester, whereas the most sustained suppression was achieved with the 1-ml gluteal injection. Plasma inhibin concentrations were also significantly influenced by injection volume and site, with the lowest nadir occurring after the nandrolone decanoate 1-ml gluteal injection. Thus, the bioavailability and physiological effects of a nandrolone ester in an oil vehicle are greatest when the ester is injected in a small (1 ml vs. 4 ml) volume and into the gluteal vs. deltoid muscle. We conclude that the side-chain ester and the injection site and volume influence the pharmacokinetics and pharmacodynamics of nandrolone esters in an oil vehicle in men.

Research utilization in a metropolitan children's hospital

A model of research utilization directing clinical practice has been described. Clinical practice is conceptualized as a pyramid, with research knowledge forming the base. Department and unit-level activities are designed to promote the identification of research-based practices for incorporation into practice. Practice Committee structures are designed to facilitate the dissemination and utilization of research-based practices. This model has evolved over the past 10 years, and current refinements include movement toward an interdisciplinary focus, support of unit level practice groups, and increased integration of the work of each practice committee.

Recruitment of minority subjects for intervention research

Recruitment of ethnic or racial minority subjects for health intervention research is a methodologic challenge. A recruitment plan that consisted of a feasibility analysis, recruitment strategies and activities, and evaluation was developed and used for a smoking cessation study of pregnant Latinas. Specific recruitment recommendations for similar research consist of a thorough feasibility analysis, developing partnerships with target groups and community members, using active face-to-face recruitment, and using process evaluation techniques.

A skin cancer training programme: evaluation of a postgraduate training for family doctors

This study aimed to evaluate the effectiveness of a postgraduate skin cancer training programme in improving family doctors' levels of knowledge and clinical practice. Forty-one of 59 family doctors (69% consent) who enrolled in the training programme agreed to participate in its evaluation. Approximately half of the doctors were allocated to the 'intervention' group, and the others were in the 'waiting-list' control group. Pre- and post-test data were collected to assess changes in doctors' knowledge, perceived confidence and clinical practice. The training programme involved three sessions, including an information/education session, a practical session at the local Melanoma Unit, and a practical surgical procedures session. There were significant improvements in the proportion of (i) accurate diagnoses, which were made when lesions were presented on colour slides with an accompanying case history; (ii) lesions presented on colour slides in which the correct management of the lesion was identified; and (iii) doctors who felt very or extremely confident in their ability to advise patients on screening frequency, to advise patients on the signs of skin cancer, and to decide whether changes in lesions were malignant. The only improvement observed in the doctors' clinical practice was a significant increase from pre- to post-test in the proportion of pathology request forms on which a diagnosis of the specimen was attempted by doctors in the intervention group compared to those in the control group. The results of this study indicate that whilst significant improvements in knowledge are achievable through postgraduate programmes, clinical practice is much more difficult to change.

Comparative genomic hybridization detects novel deletions and amplifications in head and neck squamous cell carcinomas

To gain a better understanding of genetic changes in squamous cell carcinomas of the head and neck we used comparative genomic hybridization for the analysis of 13 primary tumors. Copy number increases were most frequently observed on chromosomes 3q (10 cases) and 5p (8 cases) and less frequently on 1q (4 cases), 2 (1 case), 7 (2 cases), 8q (2 cases), 9 (1 case), 10p (2 cases), 13q (2 cases), 14q (1 case), 16 (1 case), 17 (2 cases), 20p (2 cases), 21q (1 case) and 22q (1 case). Copy number decreases occurred most frequently at 3p (5 cases), 5q (4 cases), 19p (6 cases), and 19q (5 cases). Copy number decreases also were observed on 1p (2 cases), 2q (2 cases), 4p (2 cases), 4q (2 cases), 7q (2 cases), 8p (1 case), 10q (1 case), 11p (2 cases), 11q (3 cases), 13q (3 cases), 14q (1 case), 16p (1 case), 17p (3 cases), 17q (1 case), 18q (1 case), and 22 (2 cases). Eight sites exhibiting significant sequence amplification were mapped to 3q26-->qter (3 cases), 11q13 (2 cases), 12p (2 cases), 2q33-36 (1 case), 7q21-22 (1 case), 7q33-->qter (1 case), 9p (1 case), and 13q32-->qter (1 case). Our data suggest that the regions 3q26-->qter and 5p may harbor oncogenes important for initiation or progression of squamous cell carcinomas of the head and neck. In addition, comparative genomic hybridization defines a subgroup of tumors with 11q13 involvement, the location of the PRAD1/(CCND1)/cyclin D1 gene.

Marrow transplants from HLA matched unrelated donors: an NMDP update and the Seattle experience

It is now possible to access more than one million HLA-A, B typed volunteer individuals willing to donate marrow and a preliminary search through the NMDP registry provides access to more than 200,000 HLA-A, B, DR typed donors. Fifty-four percent of preliminary searches yield at least one potentially HLA-matched donor but the majority of these successful searches involve patients of Caucasian origin. Substantially greater recruitment must occur among different racial and ethnic groups if minority patients are to have a better chance of finding an HLA match. This can be accomplished by recruiting diverse donors within each regional registry or by expanding worldwide the existing international registry network. Molecular typing and matching for alleles in the HLA-D region improve the precision of donor selection and the timeliness of the donor search process. Although the risk of GVHD in unrelated donor transplants remains higher than in HLA-identical sibling transplant is not as good as HLA-identical sibling transplants, newer methods of supportive care and GVHD control are providing and gradual improvement in both the safety of the procedure and long-term relapse-free survival.

Proteolipid protein gene expression in demyelination and remyelination of the central nervous system: a model for multiple sclerosis

We asked whether nonlethal injury to the oligodendrocyte as manifested by altered myelin gene expression is an early event in the pathogenesis of demyelinating disease and subsequent remyelination. Using simultaneous in situ hybridization and immunocytochemistry, we studied expression of proteolipid protein (PLP) antigen and mRNA in spinal cords of normal adult mice and of mice infected with Theiler's virus which provides an excellent model for multiple sclerosis. Downregulation of PLP mRNA was observed within 3 days and persisted for as long as 367 days following intracerebral virus infection of SJL/J mice which are susceptible to chronic demyelination. Downregulation of myelin gene products preceded the development of prominent inflammation and demyelination observed following virus infection. In contrast, no change from control uninfected mice was observed in the expression of PLP mRNA following infection of C57BL/10SNJ mice which are resistant to demyelination. Treatment of chronically infected susceptible SJL/J mice with a regimen which promotes CNS-type (oligodendroglial) remyelination resulted in a 3- to 4-fold increase in PLP mRNA expression in oligodendrocytes. Actin mRNA expression in PLP antigen-positive cells was unchanged following TMEV-induced demyelination or remyelination indicating up- or downregulation of myelin gene products as compared to constitutively expressed actin gene. These experiments support the hypothesis that early regulation of myelin gene expression may be an important determinant in demyelination and in remyelination following nonlethal injury to oligodendrocytes.

Regional mapping of 22 microclones around the adenomatous polyposis coli (APC) locus on chromosome 5q

A previously described genomic library constructed from microdissected DNA has been used to generate a large number of probes around the adenomatous polyposis coli (APC) gene at 5q22. A total of 202 clones were hybridised directly onto a somatic cell hybrid panel containing two APC-related interstitial deletions. Of 75 microclones that gave clear hybridisation signals, 22 independent clones mapped into the region common to both deletions. In addition, 4/22 of the markers are conserved in rodent DNA. These clones should provide a valuable resource for screening cDNA libraries and cloning the DNA around the APC gene in yeast artificial chromosomes.

In vitro effects of bryostatin 1 on the metabolism and cytotoxicity of 1-beta-D-arabinofuranosylcytosine in human leukemia cells

Bryostatin 1 is a macrocyclic lactone protein kinase C (PK-C) activator which has demonstrated promising antileukemic activity in preclinical studies. We have examined the effect of this agent on the metabolism and cytotoxicity of 1-beta-D-arabinofuranosylcytosine (ara-C) in both log phase and high-density human promyelocytic leukemia cells (HL-60). Exposure of low-density cells to 12.5 nM bryostatin 1 for 24 hr prior to a 4-hr incubation with 1 or 10 microM ara-C resulted in nearly a 2-fold increase in ara-CTP formation. When cells were maintained under high-cell density conditions (e.g. 5 x 10(6) cells/mL) for 24 hr prior to ara-C exposure, a 90% reduction in ara-CTP formation and ara-C DNA incorporation was observed. However, coincubation of high-density cells with bryostatin 1 for 24 hr increased ara-CTP formation 6- to 8-fold, yielding levels essentially equivalent to those achieved in low-density cells. Smaller (but still significant) increases in ara-C DNA incorporation were also noted. Enhancement of ara-CTP formation by bryostatin 1 occurred over a broad ara-C concentration range (0.1 to 100 microM), involved a temperature-dependent process, could not be mimicked by addition of hematopoietic growth factors, and was not related to neutralization of toxic or inhibitory substances in high-density medium. Exposure of cells to bryostatin 1 did not lead to morphologic or functional evidence of HL-60 cell maturation or an increase in cell viability, but did produce a decline in cellular proliferative activity as determined by thymidine and bromodeoxyuridine incorporation and cytofluorometric analysis. Bryostatin 1 did not exert its effects in high-density cells by inhibiting ara-C deamination or by interfering with ara-CTP dephosphorylation, but instead appeared to act by enhancing ara-C phosphorylation. Although cell-free extracts obtained from high-density cells exposed to bryostatin 1 exhibited levels of deoxycytidine kinase activity compared to controls, treated cells did display a significant decline in intracellular dCTP levels (e.g. 0.7 vs 1.3 pmol/10(6)), and nearly a 2-fold increase in ATP and UTP concentrations. Ara-CTP formation was also increased substantially by other PK-C activators including phorbol dibutyrate and mezerein (10-100 nM); this process was inhibited more than 70% by the PK-C inhibitor H-7 (50 microM), but not by the PK-C inhibitors staurosporine, tamoxifen, and HA1004. Finally, coadministration of ara-C and bryostatin 1 resulted in greater than expected inhibitory effects toward HL-60 cell clonogenic growth.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of the protein kinase C activating agent bryostatin 1 on the clonogenic response of leukemic blast progenitors to recombinant granulocyte-macrophage colony-stimulating factor

Bryostatin 1 is a macrocyclic lactone activator of protein kinase C which has displayed promising antileukemic potential in pre-clinical studies. We have assessed the effect of bryostatin 1 on the in vitro clonogenic response of leukemic myeloblasts obtained from 12 patients with acute non-lymphocytic leukemia to recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF), and have compared these responses to those of normal human hematopoietic progenitors. Although leukemic blast progenitors responded in a heterogenous manner to bryostatin 1 as a single agent, co-administration of 12.5 or 100 nM bryostatin 1 in conjunction with 1.25 ng/ml rGM-CSF resulted in a significant reduction in colony formation (compared to rGM-CSF alone) in 8/12 specimens, and sub-additive stimulatory effects in all samples. In addition, the exposure of cells to 12.5 nM bryostatin 1, either alone or in conjunction with 1.25 ng/ml rGM-CSF, substantially reduced or eliminated leukemic cell self-renewal capacity in all samples assayed. In contrast to the effects observed in leukemic cells, exposure of adherent and T-cell depleted normal bone marrow mononuclear cells to equivalent concentrations of bryostatin 1 and rGM-CSF consistently produced supra-additive effects on the growth of normal committed myeloid progenitors (day 14 CFU-GM). When normal marrow cells were further enriched for progenitors (MY-10+), concentrations of bryostatin 1 that were unable to support growth when administered alone significantly potentiated the number of GM colonies formed in response to rGM-CSF. These studies suggest that bryostatin 1 may modulate the in vitro response of certain normal and leukemic progenitor cells to rGM-CSF, and that the nature of this response differs between the two cell types. They also indicate that bryostatin 1 may be particularly effective in limiting the self-renewal capacity of leukemic myeloblasts, an in vitro characteristic with potentially important in vivo significance.

Effect of pharmacologic manipulation of protein kinase C by phorbol dibutyrate and bryostatin 1 on the clonogenic response of human granulocyte-macrophage progenitors to recombinant GM-CSF

The effect of pharmacologic manipulation of protein kinase C (PK-C) activity on the response of committed human myeloid progenitor cells (CFU-GM) to recombinant human granulocyte-macrophage colony stimulating factor (rGM-CSF) was assessed. Coadministration of the PK-C activating agents, phorbol dibutyrate (PDBu) or bryostatin 1, with rGM-CSF resulted in a dose-dependent and, under some conditions, highly synergistic increase in the number of CFU-GM. With optimal combinations, colony formation far exceeded that which could be obtained with high concentrations of rGM-CSF alone. High concentrations of PDBu (e.g. greater than or equal to 50 nM), but not bryostatin 1, completely inhibited the CFU-GM response. These inhibitory effects could be reversed by bryostatin 1, but not by high concentrations of rGM-CSF. Bryostatin 1 also potentiated colony formation in response to rGM-CSF, and blocked the inhibitory effects of high concentrations of PDBu in bone marrow cells highly enriched for progenitors bearing the MY-10 antigen. The increase in CFU-GM induced by PDBu or bryostatin 1 was associated with little change in the morphologic type of colony observed. Continuous exposure of cells to the calcium ionophore, ionomycin (500 nM), reduced the number of granulocyte-macrophage colonies, but produced little change in the concentration-response of rGM-CSF and PK-C activating agents. Finally, the PK-C inhibitors H-7 and tamoxifen, when administered at concentrations exhibiting minimal inhibitory effects in the presence of rGM-CSF alone, led to no change or small increases in the numbers of colonies formed in response to rGM-CSF and bryostatin-1, and a substantial increase in the number of colonies formed in the presence of rGM-CSF and PDBu. These results suggest that PK-C activation may play a complex role in regulating the response of normal myeloid progenitors to growth factors such as rGM-CSF. They also raise the possibility that under some circumstances the phorbol ester PDBu may trigger events that inhibit the growth of myeloid progenitors, and that this process may be blocked by bryostatin 1.