A novel "embryo-endometrial" adhesion model can potentially predict "receptive" or "non-receptive" endometrium

OBJECTIVE

To establish a model of human implantation that responds to hormonal stimuli and can differentiate between endometrium from fertile women and those with idiopathic infertility.

DESIGN

A trophoblast stem cell (trophectodermal) line (TSC; derived from human pre-implantation embryo) was used to form trophectodermal spheroids (TS). TS attachment to monolayers of endometrial epithelial cell lines or primary endometrial epithelial cells (pHEECs) was determined.

SETTING

Independent Medical Research Institute with close clinical linkages INTERVENTIONS: Spheroid attachment and outgrowth was determined with added hormones (estradiol 17β (E), E + medroxyprogesterone acetate (MPA) or E + MPA + human chorionic gonadotropin (hCG)). Spheroid attachment to E/MPA treated pHEEC prepared from fertile women or those with idiopathic infertility tested.

MAIN OUTCOME MEASURE

Firmly attached spheroids counted after co-culture for 6 h. Outgrowth was determined by quantitation of area covered by spheroid after firm adhesion.

RESULTS

Functional adhesion of TS to two endometrial epithelial cell lines, Ishikawa and ECC-1 cells, was hormonally responsive, with adhesion/outgrowth increased by E/MPA (ECC-1; p < 0.01, Ishikawa; p < 0.01) and E/MPA/hCG (ECC-1; p < 0.001, Ishikawa p < 0.01) versus E alone. The same pattern of hormone responsiveness was observed in pHEEC obtained from fertile women (E vs, E/MPA; p < 0.01, E vs. E/MPA/hCG; p < 0.001). TS adhered to 85% of pHEEC obtained from fertile women (11/13) and 11% of pHEEC obtained from women with unexplained infertility (2/18, p < 0.001).

CONCLUSION

This new model of "embryo" implantation largely discriminates between endometrial epithelial cells obtained from fertile vs. infertile women based on adhesion; this holds potential as an in vitro "diagnostic" tool of endometrial infertility.

The Performance and Safety of a Pleural Drainage Unit under Hyperbaric Conditions

The performance of a proprietary dry suction pleural drainage unit was measured under hyperbaric oxygenation conditions. The test pleural drainage unit was connected to pressure gauges that allowed the pressures created in the suction and collection chambers to be measured as well as the pleural drainage catheter pressures under varied suction regulator settings during compression, hyperbaric steady states and decompression. The maximum flow capacity of the unit was also measured under varying hyperbaric conditions.

The Atrium Oasis Dry Suction 3600 Chest Drain brand was dramatically affected by pressure change. Nevertheless, based upon our testing, we believe it can be used safely in a hyperbaric environment provided that the following precautions are taken.

Suction should not be applied during pressurization. Pressurization needs to be slow, 10 kpa/min or less. Suction is needed for air leaks of 4 l/min or more at pressure. At stable hyperbaric pressure, the level of suction delivered can be set by adjusting the suction regulator with reference to the conversion table we have determined. Suction must be applied during depressurization if there is an air leak of 5 l/min or greater coming from the patient, otherwise suction is not essential.

As the features of many brands and models of proprietary drains are similar, we would expect other types could be hyperbaric compatible, but individual testing should be performed before acceptance.

The concentration-independent effect of monoexponential and biexponential decay in vancomycin concentrations on the killing of Staphylococcus aureus under aerobic and anaerobic conditions

An in-vitro pharmacodynamic system was used to generate time-kill curves to demonstrate the concentration-independent pharmacodynamics of vancomycin against Staphylococcus aureus ATCC 29213. Initial vancomycin concentrations of 5, 10, 20 and 40 mg/L were studied monoexponentially while simulating a 6 h half-life. One parallel experiment was performed in duplicate using an initial peak concentration of 40 mg/L where both a distribution alpha-phase half-life of 0.66 h for 1 h and an elimination beta-phase half-life of 6 h for 11 h were simulated to determine if the transient distribution phase concentrations of vancomycin have any impact on bacterial killing beyond that provided by the elimination phase concentrations. Additionally, two monoexponential experiments with peak concentrations of 40 and 20 mg/L and a half-life of 6 h were repeated in an anaerobic chamber to determine if killing of S. aureus was affected. The time to achieve a 3 log10 kill was calculated from the linear portion of the regression line and averaged (mean +/- S.D.) 9.0 +/- 1.4 h for all aerobic monoexponential experiments and was 8.4 and 8.6 h for the aerobic biexponential experiments (P > 0.05). For the anaerobic studies, the times to reach 3 log10 kill were significantly greater averaging 18.9 +/- 1.7 h. The slopes of the bacterial kill curves were virtually identical for both monoexponential and biexponential aerobic experiments averaging -0.34 +/- 0.04, yet significantly different from the anaerobic bacterial kill curve slopes of -0.16 +/- 0.015 (P < 0.05). Time-kill curve analyses suggest that varying the concentration of vancomycin does not affect the rate or extent of bacterial killing aerobically or anaerobically against S. aureus and more efficient killing was achieved under aerobic conditions. The simulated distribution phase concentrations did not contribute to more effective killing of this strain of S. aureus.

Effect of aerobic and anaerobic environments on antistaphylococcal activities of five fluoroquinolones

A previously established in vitro pharmacodynamic system was used to evaluate the antistaphylococcal activities of five fluoroquinolones under both aerobic and anaerobic conditions. Staphylococcus aureus ATCC 29213 was exposed to a 5-micrograms/ml concentration of each of the following fluoroquinolones: ciprofloxacin, ofloxacin, temafloxacin, sparfloxacin, and clinafloxacin. Terminal elimination half-lives of 4, 6, 8, 8, and 13 h were simulated for the respective drugs. Each fluoroquinolone was bactericidal under both aerobic and anaerobic conditions. However, the bactericidal activity of each fluoroquinolone was delayed by anaerobiosis. This difference in fluoroquinolone activity under aerobic and anaerobic conditions could not be attributed to any particular parameter or physiochemical property but was most likely caused by a combination of factors (e.g., variations in hydrophobicity, intracellular pH, antibiotic concentration, and structure-activity relationships). Fluoroquinolone uptake studies were also performed to investigate the possibility of active, energy-dependent transport mechanisms in S. aureus ATCC 29213. Uptake studies indicated that active efflux does occur in S. aureus ATCC 29213.

Evaluation of antimicrobial activities of clarithromycin and 14-hydroxyclarithromycin against three strains of Haemophilus influenzae by using an in vitro pharmacodynamic model

An in vitro pharmacodynamic model was used to simulate the in vivo pharmacokinetics of clarithromycin and 14-hydroxyclarithromycin in order to generate time-kill curves for three clinical isolates of Haemophilus influenzae (isolates 2019, 91-183, and 1746). Representative concentrations in serum or lung tissue and the pharmacokinetic parameters of clarithromycin and the 14-hydroxy metabolite, separately and in combination, were simulated for the time-kill studies. Amoxicillin-clavulanic acid was used as a control drug. The simulation of typical concentrations of the macrolides in serum in time-kill studies resulted in magnitudes of bacterial killing that were less than (for strains 2019 and 91-183, MICs = 4 mg/liter for clarithromycin and 14-hydroxy-clarithromycin) or equal to (for strain 1746, MIC = 1 mg/liter for clarithromycin and 14-hydroxyclarithromycin) those observed in amoxicillin-clavulanic acid studies. When typical concentrations in lung tissue were simulated, total log decreases in bacterial counts were greater than those achieved with typical concentrations in serum and, in the case of strain 1746, exceeded the magnitude observed with the control drug. In each case, the time to 3-log-unit killing was longer for the macrolides than for amoxicillin-clavulanic acid. Time-kill curve analyses demonstrated the presence of synergy (defined as a 2-log-unit decrease in the CFU per milliliter between the combination and the most active constituent at any time point) for the combination of clarithromycin and 14-hydroxyclarithromycin at simulated concentrations in serum for one strain of H. influenzae (isolate 91-183). Synergism is likely bacterial strain specific, and the presence of synergy may be dependent on the antibiotic concentrations that are tested. Evaluation of the kill curve kinetics in terms of bactericidal rate for the various starting concentrations of clarithromycin did not result in a clear demonstration of either concentration-dependent or concentration-independent bactericidal activity.

Letters

JOURNAL POLICY DEBATE COMPARING DRESSINGS.

Evaluation of activity of temafloxacin against Bacteroides fragilis by an in vitro pharmacodynamic system

An in vitro pharmacodynamic system has been successfully adapted to simulate in vivo antimicrobial pharmacokinetics under anaerobic conditions. This system was used to perform time-kill kinetic studies which were designed to compare the activity of temafloxacin to ciprofloxacin and cefotetan against two strains of Bacteroides fragilis (ATCC 25285 and ATCC 23745). All experiments were performed as single-dose, 24-h, duplicate runs. Starting bacterial inocula of 10(7) CFU/ml were exposed to starting antimicrobial concentrations of 5 micrograms of temafloxacin per ml, 5 micrograms of ciprofloxacin per ml, and 100 micrograms of cefotetan per ml. Terminal half-lives of 8, 4, and 4 h were simulated for each antimicrobial agent. Temafloxacin was rapidly bactericidal against B. fragilis. Ciprofloxacin was not bactericidal (< 3 log10 unit decline in bacterial numbers) to either strain of B. fragilis. Cefotetan was bactericidal (> or = 3 log10 unit decline in bacterial numbers) to each strain but killed at a slower rate than temafloxacin. Times to 3 log10 unit declines of strain ATCC 25285 were 2, 4, and > 24 h, whereas those of strain ATCC 23745 were 4, 4, and > 24 h for temafloxacin, cefotetan, and ciprofloxacin, respectively. Total logarithmic declines of strain ATCC 25285 were > 4.5, > 4.5, and 2.9 log10 CFU/ml, whereas those of strain ATCC 23745 were 4.1, > 4.5, and 1.2 log10 CFU/ml for each drug, respectively. These and other studies demonstrated that temafloxacin showed potential as an agent that could have been further developed for use in the treatment of anaerobic infections. However, the drug was removed from the market by its manufacturer because of toxicity issues. Although the release of newer fluoroquinolones that possess significant activity against anaerobic bacteria does not appear imminent, the time-kill studies performed in this study demonstrate that further research is warranted in the development of fluoroquinolones which possess significant antianaerobic activity.

Clostridium difficile colonization in residents of long-term care facilities: prevalence and risk factors

OBJECTIVE

To determine the period prevalence of Clostridium difficile disease and asymptomatic carriage in the residents of long-term care facilities (LTCF) and to characterize the risk factors for colonization or associated disease.

DESIGN

Period prevalence survey.

SETTING

Two long-term care facilities in St. Paul, MN.

PARTICIPANTS

Specimens were collected from 225 LTCF residents.

MEASUREMENTS

The dependent variable was the culture result for C. difficile, which was isolated and identified using selective culture media and a commercial anaerobe identification kit. Tissue culture assay was used to detect the ability of each C. difficile isolate to produce toxin. Independent variables (including gender, age, race, current medical diagnoses, severity of underlying disease, case mix, current clinical symptoms, current medications, antibiotic use within 4 weeks prior to specimen procurement, and other pertinent history) were obtained from the current medical record of each participant.

RESULTS

Of 225 stool cultures that were obtained, 16 (7.1%) were positive for C. difficile. None of the residents with a positive culture was symptomatic. History of nosocomial infection and the use of antibiotics in general, cephalosporins, trimethoprim/sulfamethoxazole (TMP/SMX), and histamine-2 blockers were significantly associated with positive C. difficile culture (P < or = 0.05) by univariate analyses. Trends towards significance (0.05 < 0.10) were noted for narcotic use, previous hospitalization, LTCF, and non-insulin-dependent diabetes mellitus. Logistic regression analysis revealed significant, independent predictors of positive culture: antibiotic use in general (P = 0.028; relative risk = 3.31), histamine-2 antagonist use (P = 0.038; relative risk = 3.27), cephalosporin use (P = 0.038; relative risk = 4.66), and TMP/SMX use (P = 0.007; relative risk = 8.45).

CONCLUSIONS

The use of antibiotics, particularly cephalosporins and TMP/SMX, is a significant risk factor for asymptomatic carriage of C. difficile in long-term care facilities. The use of H-2 blockers was also a significant risk factor for carriage; however, this finding has not been reported previously and should be confirmed by independent studies. These medications should be used judiciously in the LTCF population. When diarrheal diseases are encountered in LTCF residents, a high index of suspicion for C. difficile infection should be maintained and the appropriate diagnostic and therapeutic measures taken.

Elimination of quinolone antibiotic carryover through use of antibiotic-removal beads

To prove the utility of antibiotic-removal beads in separating antibiotics from bacterial samples, Escherichia coli ATCC 25922 was exposed to five separate quinolones before and after each was exposed to antibiotic-removal beads. Plates treated with antibiotic solutions that were exposed to beads demonstrated antibiotic removal, and plates treated with antibiotic solutions that were not exposed to beads demonstrated antibiotic carryover. After exposure to beads, fluoroquinolone concentrations decreased from 5 micrograms/ml to 0.14 micrograms/ml (ciprofloxacin), 0.04 micrograms/ml (temafloxacin), < 0.01 microgram/ml (ofloxacin), < 0.01 microgram/ml (sparfloxacin), and 0.02 micrograms/ml (clinafloxacin). These data indicate that antibiotic carryover can be successfully circumvented through the use of antibiotic-removal beads.

Pharmacotherapy and pharmacodynamics in the management of bacterial infection

Minimum inhibitory concentration testing is the most common standard used to evaluate antibacterial activity of antimicrobials against specific pathogens. The consideration of pharmacodynamic factors in conjunction with these tests can improve the management of bacterial infections. Further, the incorporation of MIC values into pharmacodynamic ratios may provide clinically useful tools for selecting optimal antibiotic selection, determining proper dosing strategies, and predicting therapeutic outcomes. Physiologic consequences of infection and antibiotic treatment, such as endotoxin release and initiation of the septic cascade, also must be considered when choosing appropriate anti-infective therapy. The introduction of adjuvant immunotherapy, along with improvement, validation, and implementation of pharmacodynamic predictors of antibiotic efficacy, undoubtedly will provide the medical community with an effective arsenal to further reduce the morbidity and mortality rates associated with bacterial infections.

Heterogeneity of oestrogen receptor expression in normal and malignant breast tissue

The heterogeneity of oestrogen receptor (ER) expression has been examined in both normal and malignant breast tissue using an immunohistochemical assay. In both instances the ER status and cellular ER negativity were influenced by the patients' menopausal status, with tissues removed from premenopausal women being more often ER-negative, and when ER-positive, containing a high proportion of apparently ER-negative cells. Since the breast is normally regarded as hormone sensitive and since tumour cell ER negativity is apparently under a degree of hormonal regulation, our results suggest that the proportion of breast cancer cells that are ER-negative should be viewed with a degree of caution.

Influence of the antioestrogen tamoxifen on normal breast tissue

Immunohistochemical assays have been employed to study the expression of ER, PgR, EGFR and Ki67 immunostaining in normal breast tissue (n = 76). The expression of ER and PgR was highly variable in both pre and postmenopausal women and was characterised by large numbers of apparently negative cells. This was most evident for ER-ICA staining in tissues removed from premenopausal women. PgR levels were highest in the ducts of premenopausal women, while EGFR expression was elevated in both ducts and lobules. Ki67 expression was observed in less than 10% of all normal cells and was suppressed by the menopause in lobular tissue. Tamoxifen therapy (40 mg d-1) did not influence the expression of PgR, EGFR or Ki67 immunostaining in cancer associated normal tissue (n = 17). A significant increase, however, was observed in the mean percentage ER positivity in ductal tissue. No effect of duration of tamoxifen therapy was observed on the expression of the antigens studied.

Hormone sensitivity in breast cancer: influence of heterogeneity of oestrogen receptor expression and cell proliferation

The percentage of oestrogen receptor (ER) positive cells in a series of 118 breast cancers has been examined by immunohistochemistry in relation to patients' response to endocrine therapy. Positive and negative predictive values have been used to calculate appropriate cut-off points. The rate of response to treatment was significantly higher in women with receptor positive tumours, especially where the tumours contained more than 70% positive cells. Tumours that were apparently negative for ER expression rarely responded to endocrine therapy. The hormone sensitivity of ER positive breast cancer was also influenced by the rate of tumour cell proliferation, with tumours expressing high levels of Ki67 immunostaining rarely responding to therapy.

Zoladex plus tamoxifen versus Zoladex alone in pre- and peri-menopausal metastatic breast cancer

Phase II studies examining the endocrinological and clinical efficacy of Zoladex and Zoladex plus tamoxifen have been examined in pre- and peri-menopausal women with advanced breast cancer. No adverse endocrinological interaction between the drugs have been observed. Although a higher proportion of static disease was observed with the combination of the drugs, which possibly occurred at the expense of partial remissions, the time to disease progression was extended in women who received Zoladex plus tamoxifen. Remissions were primarily restricted to patients whose tumours were ER positive. Only occasional responses were seen in ER negative disease. This was especially evident where the ER negative tumours were EGF-R positive and showed high rates of cell proliferation.

Goserelin (Zoladex) in premenopausal advanced breast cancer: duration of response and survival

In premenopausal women with advanced breast cancer the luteinising hormone-releasing hormone agonist goserelin (Zoladex, ICI plc) will produce serum levels of oestradiol equivalent to those following surgical oophorectomy or the menopause. This paper reports our further experience of using this drug in 75 premenopausal patients with advanced breast cancer. In addition to response rates, duration of response is reported. An objective response was seen in 25 patients (33%), the median duration of which was in excess of 15 months. Seven patients (9%) showed a complete response to therapy; median duration greater than 37 months. There was no significant difference in time to disease progression (Lee-Desu statistic 18.26, 1 d.f., P = 0.43) and probability of survival (Lee-Desu statistic 3.41, 1 d.f., P = 0.07) between those patients assessed as having either static disease, or those showing a partial response at six months. Response to therapy correlates significantly with the oestrogen receptor status of the primary tumour (X2 = 20.59, 6 d.f., P less than 0.005). The modest side-effects, ease of administration and reversibility make this approach to therapy very attractive. This is to be remembered in that 53% of patients had disease progression whilst receiving goserelin. These patients thus avoided the unnecessary and irreversible morbidity associated with surgical oophorectomy. With the proven efficacy and minimal morbidity associated with goserelin we believe there is no current role for surgical oophorectomy in the management of premenopausal patients with advanced breast cancer.

Automated quantitation of immunocytochemically localized estrogen receptors in human breast cancer

Frozen sections of breast tumor tissue have been stained using an immunoperoxidase [estrogen receptor (ER)-immunocytochemistry] kit incorporating a monoclonal antiserum [H222] to visualize nuclear human ERs. Quantitation of specific staining has been performed by manual procedures using optical microscopy and by a computer-assisted image analysis system (CAS 100). Initial investigations with a test panel of ER-immunocytochemistry-positive tumors revealed a good qualitative agreement between CAS and manual assessments. Reduced variance was, however, observed between quantified ER-immunocytochemistry results from four experienced investigators using the CAS analysis. An extended study confirmed the relationships between CAS and manual methods of assessment. These findings were evident when studies were scored either by assessment of the percentage of positively stained cells (n = 92; r = 0.919; P less than 0.01) or by H-score calculations (n = 92; r = 0.913; P less than 0.01). A good correlation was also found between CAS quantification and the results of an ER enzyme immunoassay of 48 primary breast cancer specimens (r = 0.715; P less than 0.05). In 49 cases it was possible to relate CAS-defined ER status and levels to the subsequent response of patients to endocrine therapy. ER was assessed on specimens obtained prior to commencement of treatments for recurrent breast cancer. Presuming the presence of ER to be a prerequisite for successful therapy, very good correlations between response and both status and levels of positivity were recorded. None of 16 patients with CAS-ER-negative tumors responded to treatment, while 16 of 33 (48.4%) CAS-ER-positive patients achieved an objective response according to International Union Against Cancer criteria. A relationship between response and the degree of CAS-ER positivity was obtained when the CAS score divisions of 0, 1-100, and greater than 100 (response rates, 0, 41, and 64%, respectively) were used. These data demonstrate that automated image analysis offers a reliable, reproducible procedure for quantifying ER in immunocytochemically stained sections. It has potential advantages over manual procedures, providing less opportunity for subjective influences in scoring sections. Future advances in software design should further reduce elements of subjectivity and increase both the speed and reliability of results. We anticipate image analysis becoming a valuable tool in investigations concerning, for example, the influence of heterogeneity of steroid receptor distribution on the rate of recurrence of breast cancer after mastectomy and in the clinical course of the disease.

Estrogen deprivation in breast cancer. Clinical, experimental, and biological aspects

The endocrinological and clinical effects of an LH-RH agonist, Zoladex, and an antiestrogen, Nolvadex, in patients with advanced breast cancer are outlined and their potential in the therapy of nonmalignant diseases of the breast and high-risk states is briefly discussed. Additional data are presented to indicate that new antiestrogens are now available for experimental studies that, unlike tamoxifen, do not possess partial estrogen-like activity and that show favorable antitumor properties against DMBA-induced mammary tumors and MCF-7 human breast cancer cells in culture. The lack of agonistic effects of this new class of pharmacological agents now allows a state of total estrogen deprivation to be approached, a previously unobtainable clinical goal.

Combined endocrine effects of LHRH agonist (Zoladex) and tamoxifen (Nolvadex) therapy in premenopausal women with breast cancer

In premenopausal women with breast cancer, the use of the luteinizing hormone releasing hormone agonist, goserelin, results in the production of serum levels of oestradiol equivalent to those after surgical oöphorectomy or in postmenopausal women. The standard first line hormonal treatment for systemic breast cancer in postmenopausal women is tamoxifen. The combination of goserelin and tamoxifen in premenopausal women has been proposed. We have treated 34 premenopausal breast cancer patients with goserelin (3.6 mg) monthly and tamoxifen (20 mg) twice daily: endocrine data are available on all 34 patients. As with goserelin alone, patients on goserelin and tamoxifen showed transient stimulation of serum follicle stimulating hormone over the first 7-10 days with subsequent low gonadotrophin levels. Serum oestradiol and progesterone levels were reduced to castrate levels in all patients studied; no peaks of serum oestradiol were detected. There is no endocrinological contraindication to the use of goserelin and tamoxifen together in premenopausal women with breast cancer either as adjuvant therapy or in treating advanced disease.

Is low proteinuria an early predictor of severity of acute pancreatitis?

Serial six hourly urine collections were made for seven days on 20 patients with acute pancreatitis. Quantitative immunoassay of urinary albumin and IgG on the first urine sample after admission showed increased excretion rates in 14 and 13 patients, respectively. Urinary protein excretion rates remained normal or approached normal by seven days in 17 patients who made uneventful recoveries. The maximum urinary excretion rates of both albumin and IgG within the first 36 hours correlated with the serum C-reactive protein concentration 72 hours after admission. The highest IgG excretion rates were found in three patients who later developed severe complications. These preliminary data suggest that low proteinuria is a very early response in acute pancreatitis, and that it may reflect the severity of inflammation.

Gn-RH agonists in breast and gynaecologic cancer treatment

The effects of Gn-RH agonists in advanced breast cancer patients have been examined. In both pre- and postmenopausal women they produce pituitary gland desensitisation and a fall in circulating concentrations of LH and FSH. In premenopausal patients plasma progesterone and oestradiol levels fall to the castrate or postmenopausal range within 3-4 weeks. Tumour remissions have been observed in approximately 30% of premenopausal women and approximately 10% of postmenopausal patients. The mechanism of action of Gn-RH agonists is discussed and their use projected to other tumour types.

Ki67 immunostaining in primary breast cancer: pathological and clinical associations

Ki67 immunostaining has been performed on 136 primary breast cancers and related to various clinical and pathological features of the disease. Staining was most frequently seen in poorly differentiated tumours showing high rates of mitotic activity, but was independent of tumour size, lymph-node status and ER expression. A high level of Ki67 immunostaining was often associated with early recurrence of breast cancer after mastectomy. These data are consistent with the concept of the Ki67 antibody detecting an antigen that is closely related to cell proliferation and thus provides a clinically useful marker for this important characteristic of the tumour.

Endocrine effects of combination antioestrogen and LH-RH agonist therapy in premenopausal patients with advanced breast cancer

Thirty-eight premenopausal breast cancer patients were treated for periods up to 12 months with a sustained-release formulation of the luteinizing hormone-releasing hormone agonist goserelin [Zoladex, (D-Ser(But)6Azgly10-LH-RH); 3.6 mg depot every 4 weeks] either alone or in combination with the antioestrogen tamoxifen citrate (Nolvadex 40 mg/day). In both treatment groups serum gonadotrophin concentrations fell durig the first month of therapy and were suppressed on continued treatment. In patients treated with the combination therapy FSH concentrations were significantly reduced in comparison with goserelin alone. Relatively normal ovarian activity was observed during the first few weeks of therapy. Thereafter, oestradiol and progesterone concentrations rapidly declined in both treatment groups. Slightly lower serum oestradiol concentrations were recorded in patients receiving combination therapy. No significant adverse side-effects were recorded in either group of patients.

Review of the endocrine actions of luteinising hormone-releasing hormone analogues in premenopausal women with breast cancer

The endocrinological actions of the luteinising hormone-releasing hormone (LHRH) analogue, Zoladex (goserelin) in premenopausal women with advanced breast cancer are reviewed. LHRH analogues are an interesting addition to the currently available treatments for hormone-sensitive breast cancer in premenopausal women. Their modest side effects and ease of administration are in contrast to the risks and morbidity of surgical endocrine therapy.

Zoladex in advanced breast cancer

In the treatment of 53 premenopausal patients with advanced breast cancer, the LHRH analogue, Zoladex (goserelin), produced a response rate similar to that of surgical oophorectomy. Endocrinologically, Zoladex caused castrate levels of serum oestradiol and progesterone except in a small number of patients, where intermittent, suppressed peaks of oestradiol persisted. Treatment of 34 premenopausal patients with Zoladex combined with the anti-oestrogen tamoxifen (Nolvadex) produced significantly lower levels of serum oestradiol; all patients had castrate serum oestradiol levels. It is suggested that a prospective randomised study is necessary to determine any clinical advantage from such a combination.

Immunocytochemical localization of estrogen receptor in human breast tissue

An immunocytochemical assay for the measurement of estrogen receptor (ER-ICA; Abbott Diagnostics) has been evaluated in 163 human breast carcinomas. Specific binding was observed in the nuclei of 111 of 163 (68%) tumors. An excellent correlation was observed between the ER-ICA and the estrogen receptor enzyme immunoassay. A significant relationship was observed between ER-ICA status and percentage of ER-ICA negative cells, histological grade of malignancy, and mitotic activity of the tumors. A significant correlation was also observed between ER-ICA status and age at mastectomy with 50% of patients with ER-ICA positive breast tumors presenting with their disease over 60 years of age. No association was observed with either tumor size or patient nodal status. Examination of the proportion of negative cells within tumors revealed a trend for the acquisition of poor prognostic features to be associated with an increase in the negative cell population. Data on the recurrence free interval of these patients showed a significant recurrence free advantage in ER-ICA positive patients, particularly those whose tumors contained low numbers of negative cells.

Actions of oestrogens and antioestrogens on rat mammary gland development: relevance to breast cancer prevention

The proliferative actions of a series of antioestrogens on the development of the second thoracic mammary gland of ovariectomized immature Sprague-Dawley rats have been investigated. Evidence is presented that shows trans-tamoxifen, LY 117018 and LY 139481, like oestradiol-17 beta and cis-tamoxifen, promote full mammary gland ductal development and induce a high rate of cell proliferation in the undifferentiated epithelial cells of the terminal end buds, the main growth region for ductal growth. Conversely, ICI 164,384, a new antioestrogen, is without effect on ductal elongation. In vivo exposure of trans-tamoxifen and LY 117018 treated glands in medically castrated animals to the carcinogen DMBA, results in a high rate of mammary tumour development. Indeed, the actions of these so-called antioestrogens are equivalent to those observed in oestradiol-treated rats.

Remission of postmenopausal breast cancer during treatment with the luteinising hormone releasing hormone agonist ICI 118630

Ten previously untreated postmenopausal women with metastatic breast cancer, none of whom had received prior systemic therapy, were treated with the luteinising hormone releasing hormone (LHRH) analogue D-Ser(But)6, Azgly10-LHRH (ICI 118630). Two obtained an objective partial remission, one in bone metastases and one in lung metastases. One patient proved unassessable. Amongst the seven failures, incomplete pituitary gonadotrophin suppression over the relatively short treatment period with the daily injections was noted. The seven patients failing ICI 118630 received tamoxifen and two with high tumour oestrogen receptor values responded. LHRH analogues may provide a novel endocrine therapy for postmenopausal breast cancer although more data are needed. In this study, the monthly depot injection proved superior to daily injections with regard to gonadotrophin suppression, although it is not clear that this provides the mechanism of action.

Preliminary endocrinological evaluation of a sustained-release formulation of the LH-releasing hormone agonist D-Ser(But)6Azgly10LHRH in premenopausal women with advanced breast cancer

Twenty-four premenopausal women with advanced breast cancer were treated with a sustained-release (depot) formulation containing 3.6 mg of the LH-releasing hormone agonist D-Ser(But)6Azgly10 LHRH (ICI 118630), given s.c. every 4 weeks for periods of up to 5 months. Although ICI 118630 initially stimulated LH and FSH secretion, serum gonadotrophin concentrations were suppressed on continued treatment. Increased LH and FSH concentrations were associated with relatively normal ovarian activity during the first month of treatment, but low progesterone concentrations were found in all patients thereafter. In 22 out of 24 women, oestradiol concentrations fell during the second month to values equivalent to those observed in oophorectomized or postmenopausal women. In two patients, persistent but reduced oestradiol production was recorded throughout. No appreciable side-effect of the drug was observed.

The use of an LH-RH agonist (ICI 118630, Zoladex) in advanced premenopausal breast cancer

Fifty-three premenopausal patients presenting with advanced breast cancer have been treated with a potent new luteinising hormone-releasing hormone agonist Zoladex (ICI 118630) in a phase I clinical trial. On progression of disease 26 patients have undergone therapeutic oophorectomy. We present the clinical and endocrinological responses to treatment in 45 assessable patients. The response rate to Zoladex in this series was 31% and the ER status of the primary tumour was predictive of a response to the luteinising hormone-releasing hormone.

Endocrinological and clinical aspects of LHRH action (ICI 118630) in hormone dependent breast cancer

The effect of an LHRH agonist, D-Ser (But)6Azgly10-LHRH (Zoladex, ICI 118630) on pituitary gland and ovarian function has been investigated in patients with advanced breast cancer. In both pre and postmenopausal women ICI 118630 produced a substantial rise in circulating concentrations of gonadotrophins within 2 h of the first injection. However, on continued exposure to the drug plasma LH and FSH levels decreased to below pre-treatment values (14-21 days). This was especially evident in postmenopausal women. In premenopausal patients plasma progesterone and estradiol levels were significantly reduced after 2 and 4-6 weeks of therapy respectively, reaching values observed in oophorectomized or postmenopausal patients. No substantial acute or long-term influence of the drug on these hormones was seen in postmenopausal women. Breast tumor remissions were recorded primarily in premenopausal patients with estrogen receptor positive tumors. No responses were seen in patients with estrogen receptor negative disease. Minimal side effects were recorded.

Influence of LH-RH agonists on the growth and hormonal environment of breast and prostate cancer

Patients with advanced breast cancer or advanced prostate cancer have been treated with an LH-RH-agonist ICI 118630. A chemical castration-like response has been achieved in all patients and is associated with clinical remission of the disease.

Treatment of patients with advanced cancer of the prostate using a slow-release (depot) formulation of the LHRH agonist ICI 118630 (Zoladex)

Twenty two patients with advanced carcinoma of the prostate have been treated for up to 3 months with the slow-release (depot) formulation of the luteinizing hormone-releasing hormone (LHRH) agonist ICI 118630. Patients were randomized to receive one of three different doses of ICI 118630 of 0.9, 1.8 or 3.6 mg. The depot preparation was injected subcutaneously every 4 weeks. At the highest dose, the concentration of testosterone in serum was significantly reduced to castrate values after 2-3 weeks of therapy. The smaller doses of ICI 118630 (1.8 or 0.9 mg every 4 weeks) similarly reduced serum testosterone concentrations although, at the lowest dose, testosterone values were not suppressed in all patients during the first month. Hormonal changes were accompanied by subjective clinical improvement in symptomatic patients and there were no significant side effects. The data clearly demonstrate the considerable therapeutic potential of ICI 118630 in the depot formulation for the treatment of advanced carcinoma of the prostate.

Therapeutic significance and the mechanism of action of the LH-RH agonist ICI 118630 in breast and prostate cancer

The influence of the LH-RH agonist ICI 118630 on circulating levels of the pituitary gonadotrophins LH and FSH and the gonadal steroids oestradiol, progesterone, 17-hydroxyprogesterone and testosterone has been studied in phase I clinical trials of the drug in patients with advanced breast or prostate cancer. ICI 118630 initially stimulated plasma levels of LH and FSH. On continued treatment however, the drug reversed this response and produced a rapid decline in plasma testosterone and progesterone in male and female patients respectively. Plasma oestradiol concentrations equivalent to those seen in oophorectomised or postmenopausal women were eventually produced in all 5 female patients treated with ICI 118630. In one patient however persistent follicular activity occurred until her third menstrual cycle. No appreciable side effects of the drug were observed. These data indicate that ICI 118630 initiates a castration-like endocrine response and has potential in the treatment of hormone dependent tumours of the breast and prostate.

Therapeutic potential of the LHRH agonist, ICI 118630, in the treatment of advanced prostatic carcinoma

8 patients with advanced prostatic carcinoma were treated with the luteinising-hormone releasing-hormone agonist, ICI 118630, for up to 3 months. Patients received subcutaneous injections of ICI 118630 (either 100 micrograms or 250 micrograms daily). At the higher dose level, plasma testosterone concentrations were significantly reduced by day 14 and approximated to those previously recorded in castrated or diethylstilboestrol-treated patients. Plasma concentrations of luteinising hormone and follicle-stimulating hormone were similarly reduced. Reduction in the dose, to 100 micrograms/day, similarly reduced plasma testosterone. ICI 118630 shows considerable potential for the management of patients with advanced carcinoma of the prostate.