Imaging of small cell carcinoma of the male urogenital tract

Five cases of small cell carcinoma (three of the prostate and two of the bladder) are described to illustrate the unusual behaviour of these tumours. Cerebral, hepatic and bulky lymph node spread with large volume local disease occurred. The role the radiologist may play in these diseases is discussed.

Dual expression of human leukocyte antigen molecules and the B7-1 costimulatory molecule (CD80) on human melanoma cells after particle-mediated gene transfer

The aim of this study was to determine if human melanoma cells could be molecularly modified by particle-mediated gene transfer with a "gene gun", using genes for interferon-gamma (IFN-gamma), the B7-1 costimulatory molecule (CD80), and human leukocyte antigen (HLA)-A2, to augment expression of both HLA molecules and B7-1. Established and early passage melanoma cells transfected with human IFN-gamma complementary DNA (cDNA) produced IFN-gamma (50-5,000 pg/mL). The biological effect of this IFN-gamma transgene included an upregulation, or de novo appearance, of HLA expression. These melanoma cells had no detectable baseline surface expression of the B7-1 costimulatory molecule, but 8% to 31% of these cells became B7-1 positive with no selection procedure after gene transfer with human B7-1 cDNA. After combination gene transfer with cDNAs for both IFN-gamma and B7-1, 9% to 33% of these cells expressed both HLA-DR and B7-1. In combination gene transfer experiments with cDNAs for both HLA-A2 and B7-1, dual expression of HLA-A2 and B7-1 was achieved in 10% to 17% of the melanoma cells. Thus, the molecular modification of human melanoma cells to increase expression of both HLA and B7-1 can be achieved by particle-mediated gene delivery and presents a promising strategy to stimulate antimelanoma T-cell immunity. Key words: Melanoma; T cells; B7-1 costimulatory molecule (CD80); major histocompatibility complex.

Photoemission Studies of High- T c Superconductors: The Superconducting Gap

Over the last several years there have been great improvements in the energy resolution and detection efficiency of angle-resolved photoemission spectroscopy. These improvements have made it possible to discover a number of fascinating features in the electronic structure of the high transition temperature (T(c)) superconductors: apparently bandlike Fermi surfaces, flat-band saddle points, and nested Fermi surface sections. Recent work suggests that these features, previously thought explainable only by one-electron band theory, may be better understood with a many-body approach. Furthermore, other properties of the high-T(c) superconductors, which are difficult to understand with band theory, are well described using a many-body picture. Angle-resolved photoemission spectroscopy has also been used to investigate the nature of the superconducting pairing state, revealing an anisotropic gap consistent with a d-wave order parameter and fueling the current debate over s-wave versus d-wave superconductivity.

Computed tomography, diagnosis, staging and follow-up of pure granulosa cell tumour of the ovary

Granulosa theca cell tumours represent the largest group of hormone-secreting ovarian tumours and comprise approximately 1.5% of all ovarian malignancy. However, the prognosis and behaviour of pure granulosa cell tumours have been particularly difficult to evaluate, because in previous reports they have been grouped with granulosa theca cell tumours. Consequently, their radiological features and the possible contribution of computed tomography (CT) to clinical management has not been evaluated. We report the CT appearances of 15 patients with pure granulosa cell tumours and their clinical outcome. The results suggest the possibility of a positive relationship between histological grade and FIGO stage at presentation. Large tumour volume, extensive lymph node involvement and ascites on CT are adverse prognostic features. However, patients with abdominal masses less than 9 cm in diameter, absent or small volume lymph node disease and peritoneal and liver metastases achieved complete remission, suggesting that CT can assist in identifying those patients likely to respond best to current therapeutic regimens.

Mammography in the assessment of response to medical treatment of large primary breast cancer

The sequential mammograms of 48 patients (median age: 54 years, range: 24-84 years) undergoing primary medical treatment for large operable breast cancer at this institution were reviewed, and compared to the findings at clinical assessment. Twenty-six patients underwent endocrine therapy using tamoxifen, and 22 chemotherapy (CMF or MMM). All had more than two mammograms which were reviewed blindly by two independent radiologists. Response to treatment by both evaluation modalities was recorded using WHO definitions (NC, PR, CR, PD). Some 81% of patients achieved an objective clinical response to treatment, whilst 63% showed mammographic response. Overall comparison of clinical examination with mammography showed agreement in 38 patients (79%) and disagreement in 10 (21%). Agreement in type of response but not in its degree was found in 22 cases (46%). The results suggest that in the majority of cases mammography provides a useful adjunct to clinical examination in monitoring response to primary medical treatment for breast cancer. However, radiological factors such as unchanging microcalcification, and the continuing presence of mammographic density contribute to the discrepancy with clinical response in some tumours, and the search for alternative modalities of assessment should continue.

The role of percutaneous nephrostomy in malignant urinary tract obstruction

Percutaneous nephrostomy is a well established technique for rapid relief of ureteric obstruction and improvement of renal function. However, its role in the management of renal failure resulting from advanced abdominopelvic malignancy is controversial and there are no clear guidelines to predict which patients benefit from such intervention both in terms of survival time and quality of life. To establish a protocol for selection of patients with abdominopelvic malignancy most likely to benefit from nephrostomy for renal obstruction, the medical records of 50 consecutive patients undergoing this procedure at the Royal Marsden Hospital were reviewed. The patients were divided into four groups: Group I, renal obstruction caused by a nonmalignant complication as a result of previous surgery or radiotherapy (n = 8); Group II, renal obstruction due to untreated primary malignancy (n = 16); Group III, renal obstruction from relapsed disease with a viable treatment option (n = 8); and Group IV, relapsed disease with no conventional treatment option (n = 18). There was significant benefit from percutaneous nephrostomy in Groups I-III. The overall median survival time of Group IV patients was extremely poor: 38 days (range 6-143 days) with no long-term survivors. The results suggest that strict selection criteria should be applied to patients with a history of abdominopelvic malignancy before proceeding to percutaneous nephrostomy. No worthwhile benefit is obtained if nephrostomy is used as a palliative measure in the absence of definitive treatment.

Case report: intra-ureteric metastasis from testicular teratoma

The case report of a patient found to have intra-ureteric metastatic teratoma is presented. This has not to our knowledge previously been reported in the literature.

In-vitro resistance to zidovudine and alpha-interferon in HIV-1 isolates from patients: correlations with treatment duration and response

OBJECTIVE

To measure in-vitro antiviral drug susceptibilities of human immunodeficiency virus type 1 (HIV-1) isolates recovered from patients treated with alpha-interferon or zidovudine and patients not treated with these drugs and to examine the relation of these susceptibility measurements to duration of therapy, disease stage, and response to alpha-interferon therapy.

DESIGN

Cross-sectional study.

SETTING

Outpatient HIV clinic.

PATIENTS

Twenty-six ambulatory HIV-1-infected patients: Fifteen of these patients were receiving alpha-interferon therapy, and 11 had never received such therapy. Nine patients were participating in a clinical trial of combination therapy with zidovudine and alpha-interferon.

MEASUREMENTS

The 50% inhibitory concentration (IC50) of zidovudine and alpha-interferon was determined for HIV-1 isolates recovered from each patient. Plasma concentrations of HIV-1 p24 antigen in the nine patients in the clinical trial were measured monthly after alpha-interferon was added to zidovudine monotherapy.

RESULTS

Zidovudine IC50 (range, 0.01 to 4.87 microM) increased steadily with duration of zidovudine therapy (r = 0.57, P = 0.003). In contrast, alpha-interferon IC50 (range, 0.8 to 415 units/mL) was not related to duration of alpha-interferon treatment; in fact, high IC50s were found in isolates from patients who had never received exogenous alpha-interferon therapy. Resistance to alpha-interferon was greater in isolates from the 15 patients with the acquired immunodeficiency syndrome (AIDS) (median, 104 units/mL) than in those from the 10 patients without AIDS (median, 50 units/mL). Interferson activity was detected in plasma samples from 23 of 24 patients and was also at higher levels in patients with AIDS than in HIV-infected patients without AIDS. Reductions in plasma concentrations of HIV-1 p24 antigen in nine patients after beginning alpha-interferon therapy were greater in those with more susceptible isolates (r = -0.72, P = 0.03).

CONCLUSIONS

Interferon resistance, possibly due to endogenous interferon, is not related to duration of interferon therapy but may limit the effectiveness of interferon therapy. Determinations of interferon susceptibility may identify patients most likely to benefit from this agent.

Immunogenicity, antigenicity, and endothelial viability of aortic valves preserved at 4 degrees C in a nutrient medium

In patients undergoing aortic valve replacement, allograft valves stored at 4 degrees C in a nutrient medium have been associated with excellent immediate and long-term results. The effects of this method of prolonged storage on the antigenic, immunological and cellular characteristics of these grafts are incompletely understood. This study was designed to study these phenomena in rat aortic valves subjected to antibiotic sterilization and stored for up to 3 weeks in RPMI containing 10% fetal calf serum. Selected valves from Brown Norway rats were implanted heterotopically into the abdominal aorta of Lewis rats. Other valves were studied prior to transplantation. Antigenicity was determined by immunocytochemical staining using monoclonal mouse antibodies directed at Class I and Class II rat antigens. Immunogenicity was determined by duration of second-set skin graft survival following heterotopic aortic valve implant. Endothelial cell viability was determined by flow cytometric analysis of endothelial cells harvested from aortic valve allografts by collagenase digestion. Only fresh valves and valves stored for 1 day were positive for Class I antigens; no valves were positive for Class II antigens. Duration of skin graft survival was prolonged with greater duration of storage, but grafts remained immunogenic after 21 days of storage. Endothelial cell viability declined from 95% in the fresh valves to 64% after 21 days of storage. With prolonged duration of allograft valve storage at 4 degrees C, there is an attenuation of antigenicity, immunogenicity, and endothelial cell viability. Loss of endothelial cells may contribute to the changes in immunological responses to the valve allografts. The expression of antigens on the endothelial surface is not a reliable predictor of immunological response.

Resistance to ddI and sensitivity to AZT induced by a mutation in HIV-1 reverse transcriptase

Serial human immunodeficiency virus type-1 (HIV-1) isolates were obtained from five individuals with acquired immunodeficiency syndrome (AIDS) who changed therapy to 2',3'-dideoxyinosine (ddI) after at least 12 months of treatment with 3'-azido-3'-deoxythymidine (zidovudine, AZT). The in vitro sensitivity to ddI decreased during the 12 months following ddI initiation, whereas AZT sensitivity increased. Analysis of the reverse transcriptase coding region revealed a mutation associated with reduced sensitivity to ddI. When this mutation was present in the same genome as a mutation known to confer AZT resistance, the isolates showed increased sensitivity to AZT. Analysis of HIV-1 variants confirmed that the ddI resistance mutation alone conferred ddI and 2',3'-dideoxycytidine resistance, and suppressed the effect of the AZT resistance mutation. The use of combination therapy for HIV-1 disease may prevent drug-resistant isolates from emerging.

Imaging properties of polydioxanone and titanium ligating clips following para-aortic lymphadenectomy for testicular cancer

Stainless steel ligating clips produce serious artefacts on CT scans. Polydioxanone (PDS) and titanium ligating clips were used in 15 patients during para-aortic lymphadenectomy for residual metastatic testicular teratoma following chemotherapy, and follow-up CT images were compared with those following the use of stainless steel ligating clips. PDS ligating clips did not produce any artefacts and were progressively absorbed. Titanium ligating clips produced artefacts similar to but less intense than those of stainless steel. PDS ligating clips should be used when follow-up CT scanning is important.

Binding of epidermal growth factor to its receptor is affected by membrane phospholipid environment

Cells of epithelial origin generally require ethanolamine to grow in culture; when these cells are grown without ethanolamine, the phosphatidylethanolamine content of their membrane phospholipid becomes 1/2 to 1/3 of the normal amount, and growth stops. We have hypothesized that growth ceases because the phospholipid environment becomes unsuitable for membrane-associated function. Using ethanolamine-requiring rat mammary cells, we have investigated the possible effect of phosphatidylethanolamine deficiency on the binding characteristics of epidermal growth factor. Apparent dissociation constant for the high-affinity sites in cells having normal membrane phospholipid was 1.7 X 10(-10) M, whereas that of phosphatidylethanolamine-deficient cells was 2.7 X 10(-10) M: the difference was small, but significant. Pretreatment with phorbol ester caused the loss of high-affinity sites in cells having normal membrane, whereas binding characteristics of epidermal growth factor became refractory to the pretreatment in phosphatidylethanolamine-deficient cells. In addition, the rate of internalization of bound epidermal growth factor in phosphatidylethanolamine-deficient cells was about 1/4 of normal cells. Further, whether cells had normal or phosphatidylethanolamine-deficient membranes seemed to affect the phosphorylation patterns of membrane proteins in response to epidermal growth factor or phorbol ester. These results suggest that membrane phospholipid environment affects the activity of the epidermal growth factor receptor.

Preoperative cytology and mammography in patients with single-duct nipple discharge treated by surgery

Microdochectomy has been the routine management for single-duct nipple discharge. Our review of 176 consecutive patients surgically treated between 1975 and 1988 revealed eight patients with in situ carcinomas and seven with infiltrative carcinomas. Seventeen patients had multiple papillomas, two had atypical hyperplasia and two had atypical epitheliosis. Case selection for surgery has recently been advocated. In our study, nipple discharge cytology was helpful in 67 per cent of cases with underlying malignant pathology. Mammography was found to be unreliable, alerting suspicion in only two of 15 cases.

Gentamicin iontophoresis in the treatment of bacterial otitis externa in the guinea pig model

Pseudomonas otitis externa is one of the most common infections treated by otolaryngologists. Infections induced in 30 guinea pigs appeared similar to that seen in humans. The ears were then placed into four treatment groups: group A, which received a single cleaning; group B, which received a single cleaning followed by gentamicin drops 4 times daily; group C, which received a single cleaning followed by a single gentamicin iontophoresis treatment; and group D, the control group, which received no treatment. Infections were analyzed by grading edema, purulence, and erythema. An average of 10.2 days was required for control group to return to normal appearance. Groups A, B, and C had mean resolution times of 5.9, 4.7, and 4.3 days, respectively. Gentamicin iontophoresis appears to be promising, with results as good as drop therapy in otitis externa in the guinea pig model.