Biomedical subjects

H A Harvey

Publications and source records attributed to H A Harvey.

At least 19 recordsLinked to original sources

PubMed2004

Baseline serum NTx levels are prognostic in metastatic breast cancer patients with bone-only metastasis.

BACKGROUND: There is significant heterogeneity in survival of patients with metastatic breast cancer who have bone-only metastasis. We studied the correlation of serum N-telopeptide (NTx), a marker of bone resorption, and its correlation with clinical outcomes in patients with metastatic breast cancer with bone-only or bone plus soft tissue metastasis. PATIENTS AND METHODS: Serum was taken from 250 metastatic breast cancer patients with bone-only or bone plus soft tissue metastasis who participated in two similar randomized studies of second-line hormone therapy. An enzyme-linked immunosorbent assay specific for NTx of type I bone collagen was used to detect serum levels. RESULTS: Sixty patients (24%) had elevated serum NTx levels, using the mean + 2 standard deviations (26 nanomoles Bone Collagen Equivalents per liter) of healthy women as a cut-off. The median duration of clinical benefit was significantly shorter in the group with elevated serum NTx levels compared with the group that had normal serum NTx levels (P=0.0004). Time to progression (TTP) was also significantly shorter in the patients with elevated serum NTx at 139 days compared with 220 days (P=0.0006). Median survival was also significantly shorter in patients with elevated baseline serum NTx levels at 663 days compared with 941 days (P<0.0001). CONCLUSION: In this study, breast cancer patients with bone-only or bone plus soft tissue metastasis and elevated serum NTx levels have a shorter duration of clinical benefit, TTP and overall survival.

Adult↗

PubMed2003

Serum HER-2/neu and response to the aromatase inhibitor letrozole versus tamoxifen.

PURPOSE: To determine the effect of elevated serum HER-2/neu on the response of metastatic breast cancer patients to an aromatase inhibitor versus an antiestrogen. PATIENTS AND METHODS: Five hundred sixty-two estrogen receptor-positive metastatic breast cancer patients were randomized to first-line hormone therapy with either letrozole or tamoxifen. An automated enzyme-linked immunosorbent assay was used to detect serum HER-2/neu. RESULTS: For patients with normal serum HER-2/neu (70.5%), objective response rate (ORR; 39% in letrozole-treated patients v 26% in tamoxifen-treated patients; P =.008), clinical benefit (CB; 57% v 45%; P =.016), time to progression (TTP; median, 12.2 v 8.5 months; P =.0019), and time to treatment failure (TTF; median, 11.6 v 6.2 months; P =.0066) were significantly better in patients treated with letrozole. In the elevated HER-2/neu group (29.5%), there was no significant difference in ORR (17% in letrozole-treated patients v 13% in tamoxifen-treated patients; P =.45) or CB (33% v 26%; P =.31), but there was a strong trend in favor of a longer TTP with letrozole (median, 6.1 v 3.3 months; P =.0596) and a significantly longer TTF with letrozole (median, 6.0 v 3.2 months; P =.0418). Multivariate analysis revealed that elevated serum HER-2/neu was a negative predictor for ORR and TTP. CONCLUSION: Patients with normal serum HER-2/neu receiving letrozole demonstrated a significantly greater ORR and CB and longer TTP and TTF than patients receiving tamoxifen. Although in patients with elevated serum HER-2/neu there was no significant difference between letrozole and tamoxifen in ORR or CB, there was a strong trend favoring longer TTP and significantly longer TTF with letrozole.

Adult↗

PubMed2003

Metastatic breast cancer: overview of treatment.

Patients with metastatic breast cancer have a median survival of 2 to 3 years. Twenty percent of the patients who present with bone-only metastasis will be alive at 5 years from diagnosis. Current therapies are aimed at improving the quality of life, symptom control, and prolongation of survival. Newer endocrine and chemotherapeutic drugs are available to the medical oncologist for care of patients with metastatic breast cancer. We will briefly review the new advances in the treatment of metastatic breast cancer.

Antibodies, Monoclonal↗

PubMed2001

The mimicry of human glycolipids and glycosphingolipids by the lipooligosaccharides of pathogenic neisseria and haemophilus.

It has been known for many years that bacteria can induce autoimmune responses in humans resulting in serious disease. Recent work has shown that a number of bacteria that colonize human mucosal surfaces exclusively express antigens on their surfaces which are molecular mimics of glycosphingolipids found on human cells. These structures are important in the pathogenesis of Neisseria and Haemophilus species for both immune evasion and in the adherence and invasion of human cells. There is no evidence that colonization or infections by these bacterial species is associated with autoimmune disease.

Animals↗

PubMed2001

Receptor-mediated endocytosis of Neisseria gonorrhoeae into primary human urethral epithelial cells: the role of the asialoglycoprotein receptor.

Urethral epithelial cells are invaded by Neisseria gonorrhoeae during gonococcal infection in men. To understand further the mechanisms of gonococcal entry into host cells, we used the primary human urethral epithelial cells (PHUECs) tissue culture system recently developed by our laboratory. These studies showed that human asialoglycoprotein receptor (ASGP-R) and the terminal lactosamine of lacto-N-neotetraose-expressing gonococcal lipooligosaccharide (LOS) play an important role in invasion of PHUECs. Microscopy studies showed that ASGP-R traffics to the cell surface after gonococcal challenge. Co-localization of ASGP-R with gonococci was observed. As ASGP-R-mediated endocytosis is clathrin dependent, clathrin localization in PHUECs was examined after infection. Infected PHUECs showed increased clathrin recruitment and co-localization of clathrin and gonococci. Preincubating PHUECs in 0.3 M sucrose or monodansylcadaverine (MDC), which both inhibit clathrin-coated pit formation, resulted in decreased invasion. N. gonorrhoeae strain 1291 produces a single LOS glycoform that terminates with Gal(beta1-4)GlcNac(beta1-3)Gal(beta1-4)Glc (lacto-N-neotetraose). Invasion assays showed that strain 1291 invades significantly more than four isogenic mutants expressing truncated LOS. Sialylation of strain 1291 LOS inhibited invasion significantly. Preincubation of PHUECs in asialofetuin (ASF), an ASGP-R ligand, significantly reduced invasion. A dose-response reduction in invasion was observed in PHUECs preincubated with increasing concentrations of NaOH-deacylated 1291 LOS. These studies indicated that an interaction between lacto-N-neotetraose-terminal LOS and ASGP-R allows gonococcal entry into PHUECs.

Amino Sugars↗

PubMed2001

Modulation of gonococcal piliation by regulatable transcription of pilE.

The gonococcal pilus, a member of the type IV family of pili, is composed of numerous monomers of the pilin protein and plays an important role in the initiation of disease by providing the primary attachment of the bacterial cell to human mucosal tissues. Piliation also correlates with efficient DNA transformation. To investigate the relationships between these pilus-related functions, the piliation state, and the availability of pilin, we constructed a derivative of MS11-C9 (DeltapilE1) in which the lacIOP regulatory sequences control pilE transcription. In this strain, MS11-C9.10, the steady-state levels of pilin mRNA and protein directly correlate with the concentration of IPTG (isopropyl-beta-D-thiogalactopyranoside) in the growth medium and can reach near-wild-type levels of expression. Transmission electron microscopy (TEM) demonstrated that the number of pili per cell correlated with the steady-state expression levels: at a low level of transcription, single long pili were observed; at a moderate expression level, many singular and bundled pili were expressed; and upon full gene expression, increased lateral association between pili was observed. Analysis of pilus assembly by TEM and epithelial cell adherence over a time course of induction demonstrated that pili were expressed as early as 1 h postinduction. Analysis at different steady-state levels of transcription demonstrated that DNA transformation efficiency and adherence of MS11-C9.10 to transformed and primary epithelial cells also correlated with the level of piliation. These data show that modulation of the level of pilE transcription, without a change in pilE sequence, can alter the number of pili expressed per cell, pilus bundling, DNA transformation competence, and epithelial cell adherence of the gonococcus.

Bacterial Adhesion↗

PubMed2000

Gonococcal lipooligosaccharide is a ligand for the asialoglycoprotein receptor on human sperm.

In the present study, we show that Neisseria gonorrhoeae lipooligosaccharide (LOS) can bind to the asialoglycoprotein receptor (ASGP-R) on human sperm. This work demonstrates the presence of ASGP-R on human sperm. Binding of purified ASGP-R ligand decreased in the presence of gonococci. Binding of purified iodinated gonococcal LOS identified a protein of molecular weight corresponding to that of human ASGP-R. The presence of excess unlabelled LOS blocked binding of iodinated gonococcal LOS. Binding of wild-type gonococcal LOS to sperm was higher than that of mutant LOS lacking the galactose ligand for ASGP-R. These data suggest that the ASGP-R on human sperm cells recognizes and binds wild-type gonococcal LOS. This interaction may contribute to the transmission of gonorrhea from infected males to their sexual partners.

Asialoglycoprotein Receptor↗

PubMed2000

Macropinocytosis as a mechanism of entry into primary human urethral epithelial cells by Neisseria gonorrhoeae.

Gonococcal entry into primary human urethral epithelial cells (HUEC) can occur by macropinocytosis. Scanning and transmission electron microscopy revealed lamellipodia surrounding gonococci, and confocal laser scanning microscopy analysis showed organisms colocalized with M(r) 70,000 fluorescein isothiocyanate-labeled dextran within the cells. Phosphoinositide 3-kinase inhibitors and an actin polymerization inhibitor prevented macropinocytic entry of gonococci into HUEC.

Actins↗

PubMed1999

Effect of the potent aromatase inhibitor fadrozole hydrochloride (CGS 16949A) in postmenopausal women with breast carcinoma.

BACKGROUND: Fadrozole hydrochloride (CGS 16949A) is a highly potent, nonsteroidal aromatase inhibitor that significantly lowers estrogen levels in postmenopausal women and can be effective therapy for patients with advanced hormone-dependent breast carcinoma. Circulating estradiol, estrone, and estrone sulfate are reduced to undetectable levels within weeks of the initiation of therapy. Before this study, it was not known whether this decrease in serum estrogen levels results in altered parameters associated with cardiovascular disease. The authors examined the levels of several critical blood parameters that are important to cardiovascular risk for heart disease and thromboembolic disorders in patients treated with fadrozole. METHODS: Cholesterol, triglyceride, low density lipoprotein (LDL), high density lipoprotein (HDL), very low density lipoprotein (VLDL), antithrombin III, protein C, protein S, and fibrinogen were serially measured in 21 postmenopausal women with advanced breast carcinoma treated with various doses of fadrozole (1.8 mg/day, n=3; 2.0 mg/day, n=13; 4.0 mg/day, n=5) over 3-24 months (mean, 15.8 months). A repeated measure analysis of variance was applied to each cardiovascular variable to assess changes in the response over time. Analyses were performed separately for each dose group and were also pooled over the dose groups. RESULTS: There was no statistically significant change over time in lipid parameters, namely, total cholesterol (P=0.57), triglyceride (P=0.27), LDL (P=0.99), HDL (P=0.30), and VLDL (P=0.43), over the 24 months of therapy. There were also no significant changes in coagulation factors, namely, antithrombin III (P=0.41), protein C (P=0.49), or protein S (P=0.31), over the 24 months. However, an increase in fibrinogen that occurred over time did reach statistical significance (P=0.011). CONCLUSIONS: With the exception of acute phase reactant fibrinogen, this study did not identify an increase in parameters associated with cardiovascular disease in women treated with fadrozole, a potent aromatase inhibitor.

Aged↗

PubMed1999

Combined chemoradiotherapy for unresectable pancreatic cancer.

This study was undertaken to evaluate the efficacy of a regimen of combined chemoradiotherapy in patients with unresectable adenocarcinoma of the pancreas. An analysis was undertaken on 27 patients from January 1992 to May 1996. Patients had a median age of 70 years (range, 40-78) and Eastern Cooperative Oncology Group Performance Status of 0-2. Eighteen patients had locoregional disease (T2-T3, N0-N1, M0), and nine had metastatic disease. Chemotherapy consisted of four cycles of 5-fluorouracil 1 gm/m2/day as a continuous infusion over 110 hours, streptozotocin 300 mg/m2/day over 30 minutes on days 2-4, and cisplatin 100 mg/m2 over 2 hours on day 4 only, followed by a maintenance regimen of 5-fluorouracil and leucovorin every 2 weeks. The radiotherapy was administered as a split course concurrently with chemotherapy to a total dose of 6000 cGy. Toxicity was frequent, but there were no treatment-related deaths. Grade III and IV toxicity was primarily limited to myelosuppression, stomatitis, and gastrointestinal side effects. Fifteen patients (56%) were able to complete either three or four cycles of chemoradiotherapy. All patients were evaluable for toxicity, response, and survival. Nine patients (33%) had an objective response (four complete response 5 partial response), two remained stable, and 16 (59%) had disease progression. Median survival for the entire group was 19 weeks (2-139), and the median survival for overall responders was 56 weeks (15-139). No patient with localized disease underwent subsequent surgical resection. The authors conclude that those patients who are able to tolerate the entire treatment regimen may achieve a useful prolongation of time to tumor progression.

Adenocarcinoma↗

PubMed1999

Use of aromatase inhibitors in breast carcinoma.

Aromatase, a cytochrome P-450 enzyme that catalyzes the conversion of androgens to estrogens, is the major mechanism of estrogen synthesis in the post-menopausal woman. We review some of the recent scientific advances which shed light on the biologic significance, physiology, expression and regulation of aromatase in breast tissue. Inhibition of aromatase, the terminal step in estrogen biosynthesis, provides a way of treating hormone-dependent breast cancer in older patients. Aminoglutethimide was the first widely used aromatase inhibitor but had several clinical drawbacks. Newer agents are considerably more selective, more potent, less toxic and easier to use in the clinical setting. This article reviews the clinical data supporting the use of the potent, oral competitive aromatase inhibitors anastrozole, letrozole and vorozole and the irreversible inhibitors 4-OH androstenedione and exemestane. The more potent compounds inhibit both peripheral and intra-tumoral aromatase. We discuss the evidence supporting the notion that aromatase inhibitors lack cross-resistance with antiestrogens and suggest that the newer, more potent compounds may have a particular application in breast cancer treatment in a setting of adaptive hypersensitivity to estrogens. Currently available aromatase inhibitors are safe and effective in the management of hormone-dependent breast cancer in post-menopausal women failing antiestrogen therapy and should now be used before progestational agents. There is abundant evidence to support testing these compounds as first-line hormonal therapy for metastatic breast cancer as well as part of adjuvant regimens in older patients and quite possibly in chemoprevention trials of breast cancer.

Adult↗

PubMed1998

Emerging role of aromatase inhibitors in the treatment of breast cancer.

The new generation of potent steroidal and nonsteroidal inhibitors of the enzyme aromatase act by decreasing estrogen production throughout the body in postmenopausal women. The most potent of these agents may also inhibit estrogen synthesis within metastatic breast cancer tissue. The newly developed, orally administered, nonsteroidal competitive inhibitors, such as anastrozole (Arimidex), letrozole (Femara), and vorozole (Rizivor), are a thousand times more potent inhibitors of aromatase than is aminoglutethimide. Furthermore, these agents are highly selective. In several large randomized trials, the new inhibitors produced similar response rates as megestrol acetate (160 mg/d) in postmenopausal women with hormone-dependent breast cancer, but showed a trend toward improved response duration and survival. They also produced less weight gain and fewer cardiovascular and thromboembolic side effects. In addition, letrozole proved superior to aminoglutethimide in another randomized trial. Both anastrozole (1.0 mg/d) and letrozole (2.5 mg/d) have now been approved as second-line treatment for hormone-dependent breast cancer in postmenopausal women in whom disease has progressed following tamoxifen treatment. Either drug should replace the routine use of megestrol acetate in this setting. Ongoing clinical studies are comparing anastrozole and letrozole to antiestrogens as first-line endocrine therapy for metastatic breast cancer. Other trials will study the possible roles of these compounds as adjuvant therapy and chemoprevention for breast cancer.

Aged↗

PubMed1997

Issues concerning the role of chemotherapy and hormonal therapy of bone metastases from breast carcinoma.

A significant percentage (50-70%) of patients with metastatic breast carcinoma (MBC) will have disease involving the bony skeleton. Clonal selection mediated by parathyroid hormone-related protein and other factors may explain the high incidence of osseous metastases in MBC. The presence of specific growth factors and cytokines in the microenvironment of bone may contribute to the successful establishment and growth of metastatic lesions and also might determine response or resistance of these lesions to chemotherapy or hormonal therapy. Osteolytic bone lesions in MBC frequently give rise to serious clinical problems including bone pain, pathologic fracture, hypercalcemia, and neurologic complications. MBC often is treated with systemic chemotherapy or hormonal therapy. The purpose of this article was to review the recent published literature describing the impact of systemic chemotherapy and hormonal therapy of MBC on the response of bone lesions and their clinical course and complications. Evaluating the response of bone lesions can be problematic and may be complicated by the phenomenon of "tumor flare" that may be observed with either chemotherapy or hormonal therapy. Use of the International Union Against Cancer criteria for the response of bone lesions is recommended. Several studies report objective responses (20-60%) of lytic bone metastases to standard combination chemotherapy regimens such as cyclophosphamide, methotrexate, and 5-fluorouracil and cyclophosphamide, doxorubicin, and 5-fluorouracil, mitoxantrone and 5-FU, newer combinations, and single agents including paclitaxel and docitaxel but responses to vinorelbine may be less frequent. Complete responses of bone lesions to chemotherapy are rare but partial responses and disease stabilization can lead to long term patient benefit. A series from the M. D. Anderson Cancer Center of patients with bone metastases treated with 5-FU, doxorubicin, and cyclophosphamide chemotherapy reported a median duration of response of 14 months. In a recent multicenter study of 195 patients with lytic lesions from MBC treated with chemotherapy, the objective response rate (complete response + partial response) in bone was 18% and 65% of the patients developed at least 1 morbid skeletal event with a median onset of 7.0 months from the start of chemotherapy. Hormone-dependent breast carcinoma has a proclivity to metastasize to bone. In earlier studies comparing aminoglutethimide or medroxyprogesterone acetate with tamoxifen, a higher response rate of bone metastases was observed for the first two agents. However, in more recent studies comparing newer aromatase inhibitors, such as anastrozole, fadrozole, and letrozole, with megestrol acetate, there were no significant differences in rates of response in bone. Patients with MBC with bony lesions respond to both chemotherapy and hormonal therapy and can have a prolonged survival. Therefore such patients are in a more favorable position to benefit from adjunctive supportive therapy such as bisphosphonates intended to reduce skeletal morbidity.

Antineoplastic Agents, Hormonal↗

PubMed1997

Phase I study combining tumor necrosis factor with interferon-alpha and interleukin-2.

We evaluated the effects of the addition of escalating doses of tumor necrosis factor (TNF) to two fixed doses and schedules of a combination of interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) to determine the maximum tolerated dose of this three-cytokine combination and its feasibility as an outpatient regimen. Eighteen patients with metastatic cancer were enrolled. Each course consisted of 3 consecutive weeks of treatment with IFN-alpha 9 x 10(6) IU/m2/day intramuscularly (i.m.) or subcutaneously (s.c.) days 1, 3, and 5 each week for 3 weeks plus IL-2 continuous infusion 1 x 10(6) IU/m2/day (group A) or 3 x 10(6) IU/m2/day (group B) days 1-5 each week for 3 weeks. TNF was administered only during the first week of each course intravenously (i.v.) for 2 h on days 1-5. The dose of TNF was escalated (40, 80, 120 micrograms/m2) in cohorts of 3 patients. The most common side effects were fever, chills, and fatigue in all patients. Grade 3-4 toxicity included anemia (3 patients), thrombocytopenia (1 patients), arrhythmia (2 patients), pulmonary edema (3 patients),- and weight loss (1 patient). Five patients withdrew from study due to toxicity. The combination of the three cytokines is feasible as an outpatient regimen in one of the following combinations: (a) TNF 80 micrograms/m2/day as 2-h infusion on days 1-5 + IL-2 1 x 10(6) IU/m2/day continuous infusion on days 1-5 for 3 weeks + IFN-alpha 9 x 10(6) IU/m2/day s.c. or i.m. on days 1, 3, and 5 for 3 weeks, or (b) TNF 40 micrograms/m2/day as a 2-h infusion on days 1-5 + IL-2 3 x 10(6) IU/m2/day continuous infusion on days 1-5 for 3 weeks + IFN-alpha 9 x 10(6) IU/m2/day s.c. or i.m. on days 1, 3, and 5 for 3 weeks.

Adjuvants, Immunologic↗

PubMed1997

Ultrastructural analysis of primary human urethral epithelial cell cultures infected with Neisseria gonorrhoeae.

In men with gonococcal urethritis, the urethral epithelial cell is a site of infection. To study the pathogenesis of gonorrhea in this cell type, we have developed a method to culture primary human urethral epithelial cells obtained at the time of urologic surgery. Fluorescent analysis demonstrated that 100% of the cells stained for keratin. Microscopic analyses indicated that these epithelial cells arrayed in a pattern similar to that seen in urethral epithelium. Using immunoelectron and confocal microscopy, we compared the infection process seen in primary cells with events occurring during natural infection of the same cell type in men with gonococcal urethritis. Immunoelectron microscopy studies of cells infected with Neisseria gonorrhoeae 1291 Opa+ P+ showed adherence of organisms to the epithelial cell membrane, pedestal formation with evidence of intimate association between the gonococcal and the epithelial cell membranes, and intracellular gonococci present in vacuoles. Confocal studies of primary urethral epithelial cells showed actin polymerization upon infection. Polyclonal antibodies to the asialoglycoprotein receptor (ASGP-R) demonstrated the presence of this receptor on infected cells in the primary urethral cell culture. In situ hybridization using a fluorescent-labeled probe specific to the ASGP-R mRNA demonstrated this message in uninfected and infected cells. These features were identical to those seen in urethral epithelial cells in exudates from males with gonorrhea. Infection of primary urethral cells in culture mimics events seen in natural infection and will allow detailed molecular analysis of gonococcal pathogenesis in a human epithelial cell which is commonly infected.

Asialoglycoprotein Receptor↗

PubMed1996

Phase I trial of recombinant platelet factor 4 (rPF4) in patients with advanced colorectal carcinoma.

BACKGROUND: Recombinant platelet factor 4 (rPF4) is a naturally occurring protein found in platelet alpha granules that can inhibit angiogenesis. METHODS: In this Phase I trial, 9 patients with metastatic colorectal cancer who had failed 5-FU treatment received rPF4 at doses ranging from 0.3 to 3.0 mg/kg via 30-minute infusion. Three additional patients were treated with the 3 mg/kg dose over a 6-hour period of infusion. RESULTS: The only toxicity encountered was mild leg twitching in 2/3 patients treated with the 6-hour infusion. One patient with a history of phlebitis developed a lower extremity deep venous thrombosis after the first dose of rPF4. A mild rise in fibrinogen level was noted in several patients. Of the 11 evaluable patients, there were no clinical responses to treatment. CONCLUSIONS: rPF4 is well tolerated at the doses and schedules tested. No clinical responses were observed. Prolonged infusion schedules should be investigated.

Adult↗

PubMed1996

The role of bisphosphonates in the treatment of bone metastases--the U.S. experience.

Frequent complications of bone metastases include pain, pathologic fracture, hypercalcemia and spinal cord compression. Lytic bone metastases result from excessive activation of osteoclasts by tumor-produced cytokines. Aredia (pamidronate) is a potent bisphosphonate that inhibits osteoclast activation. In two dose-seeking phase I trials in patients with breast cancer and prostate cancer, repeated intravenous infusion of Aredia was shown to be safe and effective in reducing bone resorption and pain. In a randomized phase III trial of 377 patients with multiple myeloma, Aredia was administered in a dosage of 90 mg i.v. every 4 weeks. Compared with placebo, treatment with Aredia was associated with a significant decrease in bone pain and in the incidence and time to development of all skeleton-related events. Data from two phase III breast cancer trials each involving 300 patients are now being analyzed. The newer bisphosphonates can safely be used together with standard anticancer therapy to provide effective palliation of symptoms caused by lytic bone metastases.

Antineoplastic Agents↗

PubMed1996

Aromatase inhibitors in clinical practice: current status and a look to the future.

Aromatase inhibitors are a new class of agents that are of considerable interest for potential use as palliative therapy for hormone-dependent metastatic breast cancer in postmenopausal women. In the postmenopausal or castrate female, the process of aromatization accounts for the majority of circulating, biologically active estrogens. This report presents a clinical perspective on some of the most recent information concerning the biology and pharmacology of the aromatase enzyme and highlights the development of newer aromatase inhibitors with important therapeutic potential. Clinical questions addressed include the selection of aromatase inhibitors, the selection of the most appropriate patients for therapy with these new agents, and the positioning of these new agents with respect to other forms of endocrine therapy for breast cancer. Finally, we shall consider areas for future investigation of possible new indications for these agents in clinical medicine.

Antineoplastic Agents, Hormonal↗