Molecularly Imprinted Polymers Doped with Carbon Nanotube with Aid of Metal-Organic Gel for Drug Delivery Systems.

PURPOSE: The incidence of breast cancer worldwide has been on the rise since the late 1970s, and it has become a common tumor that threatens women's health. Aminoglutethimide (AG) is a common treatment of breast cancer. However, current treatments require frequent dosing that results in unstable plasma concentration and low bioavailability, risking serious adverse reactions. Our goal was to develop a molecularly imprinted polymer (MIP) based delivery system to control the release of AG and demonstrate the availability of this drug delivery system (DDS), which was doped with carbon nanotube with aid of metal-organic gel. METHODS: Preparation of MIP was optimized by key factors including composition of formula, ratio of monomers and drug loading concentration. RESULTS: By using multi-walled carbon nanotubes (MWCNT) and metal-organic gels (MOGs), MIP doubled the specific surface area, pore volume tripled and the IF was 1.6 times than the reference. Compared with commercial tablets, the relative bioavailability was 143.3% and a more stable release appeared. CONCLUSIONS: The results highlight the influence of MWCNT and MOGs on MIP, which has great potential as a DDS.

Tumor microenvironment-targeted poly-L-glutamic acid-based combination conjugate for enhanced triple negative breast cancer treatment.

The intrinsic characteristics of the tumor microenvironment (TME), including acidic pH and overexpression of hydrolytic enzymes, offer an exciting opportunity for the rational design of TME-drug delivery systems (DDS). We developed and characterized a pH-responsive biodegradable poly-L-glutamic acid (PGA)-based combination conjugate family with the aim of optimizing anticancer effects. We obtained combination conjugates bearing Doxorubicin (Dox) and aminoglutethimide (AGM) with two Dox loadings and two different hydrazone pH-sensitive linkers that promote the specific release of Dox from the polymeric backbone within the TME. Low Dox loading coupled with a short hydrazone linker yielded optimal effects on primary tumor growth, lung metastasis (∼90% reduction), and toxicological profile in a preclinical metastatic triple-negative breast cancer (TNBC) murine model. The use of transcriptomic analysis helped us to identify the molecular mechanisms responsible for such results including a differential immunomodulation and cell death pathways among the conjugates. This data highlights the advantages of targeting the TME, the therapeutic value of polymer-based combination approaches, and the utility of -omics-based analysis to accelerate anticancer DDS.

Efficacy of tamoxifen ± aminoglutethimide in normal weight and overweight postmenopausal patients with hormone receptor-positive breast cancer: an analysis of 1509 patients of the ABCSG-06 trial.

BACKGROUND: There exists evidence that body mass index (BMI) impacts on the efficacy of aromatase inhibitors in patients with breast cancer. The relationship between BMI and the efficacy of tamoxifen is conflicting. We investigated the impact of BMI on the efficacy of single tamoxifen and tamoxifen plus an aromatase inhibitor in the well-defined prospective study population of the ABCSG-06 trial. METHODS: ABCSG-06 investigated the efficacy of tamoxifen vs tamoxifen plus aminoglutethimide in postmenopausal women with hormone receptor-positive breast cancer. Taking BMI at baseline, patients were classified as normal weight (BMI=18.5-24.9 kg m(-)(2)), overweight (BMI=25-29.9 kg m(-)(2)), and obese (30 kg m(-)(2)) according to WHO criteria. RESULTS: Overweight+obese patients had an increased risk for distant recurrences (hazard ratio (HR): 1.51; Cox P=0·018) and a worse overall survival (OS; HR: 1·49; Cox P=0·052) compared with normal weight patients. Analysing patients treated with single tamoxifen only, no difference between overweight+obese patients and normal weight patients regarding distant recurrence-free survival (HR: 1.35; Cox P=0·24) and OS (HR: 0.99; Cox P=0·97) could be observed. In contrast, in the group of patients treated with the combination of tamoxifen plus aminoglutethimide, overweight+obese patients had an increased risk for distant recurrences (1.67; Cox P=0·03) and a worse OS (1.47; Cox P=0·11) compared with normal weight patients. CONCLUSION: BMI impacts on the efficacy of aromatase inhibitor-based treatment but not single tamoxifen.

Cyclin D1 expression in breast cancer patients receiving adjuvant tamoxifen-based therapy.

PURPOSE: The objective of our study was to determine the clinical relevance of cyclin D1 expression in hormone receptor-positive breast cancer patients who were treated with tamoxifen-based therapy. EXPERIMENTAL DESIGN: We assessed expression of cyclin D1 in surgical specimens of breast carcinoma by means of immunohistochemistry. Patients had been enrolled in either Austrian Breast and Colorectal Cancer Study Group (ABCSG) Trial 05 or ABCSG Trial 06 and received tamoxifen as part of their adjuvant treatment. Overall survival and relapse-free survival were analyzed with Cox models adjusted for clinical and pathologic factors. RESULTS: Cyclin D1 was expressed in 140 of 253 (55%) tumors of ABCSG Trial 05 and in 569 of 948 (60%) tumors of ABCSG Trial 06. Expression of cyclin D1 was associated with poor outcome in both cohorts. Overall survival was significantly shorter in patients with cyclin D1-positive tumors compared with patients with cyclin D1-negative tumors [adjusted hazard ratio (HR) for death (ABCSG Trial 05), 2.47; 95% confidence interval (95% CI), 1.08-5.63; P = 0.03; adjusted HR for death (ABCSG Trial 06), 1.78; 95% CI, 1.36-2.34; P < 0.0001]. Relapse-free survival was also shorter in patients with cyclin D1-positive tumors than in patients with cyclin D1-negative tumors [adjusted HR for relapse (ABCSG Trial 05), 2.73; 95% CI, 1.50-4.96; P = 0.001; adjusted HR for relapse (ABCSG Trial 06), 1.52; 95% CI, 1.14-2.04; P = 0.005]. CONCLUSION: Cyclin D1 expression is an independent poor prognostic factor in women with early-stage, hormone receptor-positive breast cancer who received adjuvant tamoxifen-based therapy.

Studies of the role of steroid hormone in the regulation of oocyte maturation in cattle.

BACKGROUND: The objective of this study was to investigate whether the steroid hormone(s) secreted from cumulus-oocyte complexes (COCs) is a prerequisite for bovine oocyte maturation and cumulus expansion using aminoglutethimide (AGT), a P450 cholesterol side-chain cleavage inhibitor. METHODS: In experiment 1, COCs were cultured in maturation medium with various concentrations of AGT for 22 h to determine the effective concentration of AGT to inhibit steroid hormone secretion, meiotic maturation and cumulus expansion. In experiment 2, COCs were cultured in conditioned medium (CM) and TCM-199 medium with or without 10 mM AGT to check whether steroid hormones secreted from COCs were responsible for oocyte maturation and cumulus expansion. Experiments 3 and 4 were carried out to determine whether exogenous progesterone or estradiol-17beta was able to overcome the inhibitory effects of AGT on oocytes maturation and cumulus expansion. COCs cultured in 10 mM AGT-containing medium supplemented with various concentrations of progesterone or estradiol-17beta for 22 h were examined for oocyte maturation and cumulus expansion. RESULTS: Experiment 1 showed that a concentration of 10 mM AGT in medium was sufficient to block steroid hormone secretion, oocyte maturation and cumulus expansion, and that these inhibitory effects were fully reversible. In experiment 2, the addition of 10 mM AGT to CM did not significantly prevent oocyte maturation and cumulus expansion, implying that CM contains the steroid hormone(s) secreted from COCs, which are closely associated with oocyte maturation and cumulus expansion. The results in experiments 3 and 4 demonstrated that the addition of any concentration of progesterone or estradiol-17beta in the medium did not reduce the inhibitory effects of AGT on oocyte maturation and cumulus expansion. CONCLUSION: Our results indicate that bovine oocytes surrounded by cumulus cells are prevented from maturation and cumulus expansion through the inhibition of steroid secretion due to AGT, and that these inhibitory effects of AGT on oocyte maturation and cumulus expansions can not be overcome by the addition of either progesterone or estradiol-17beta in the medium. These observations suggest that some steroid hormone(s) other than P4 and E2 secreted from bovine COCs is essential for their meiotic maturation and cumulus expansion.

Effect of combination therapy with aminoglutethimide and hydrocortisone on prostate-specific antigen response in metastatic prostate cancer refractory to standard endocrine therapy.

A prospective study was performed to investigate the combination of the aromatase inhibitor aminoglutethimide and hydrocortisone in androgen-independent prostate cancer with changes in prostate-specific antigen (PSA) level as main determinant for response. Thirty-five patients were treated with aminoglutethimide 1000 mg daily and hydrocortisone acetate 40 mg daily. PSA measurements were performed every month. If evaluable lesions were present, objective tumor assessment was done by computed tomography scan and X-ray investigations. In 12 patients (37%) the PSA value showed a confirmed response with a decline in serum level of at least 50%. Median time to progression in responding and all patients was 10.5 and 4.5 months, respectively. Median duration of response in responding patients was 9 months. Median survival for these two groups was 23 and 14.5 months, respectively. Of seven patients with measurable disease, two showed a partial response and five a stable disease. Improvement in general condition, pain and feeling of well-being was noted in two-thirds of patients. Therapy was well tolerated with mainly grade I and II adverse events in 20% of patients. We conclude that aminoglutethimide is a valuable second-line therapy for patients with androgen-independent prostate cancer.

Randomized trial of tamoxifen versus tamoxifen plus aminoglutethimide as adjuvant treatment in postmenopausal breast cancer patients with hormone receptor-positive disease: Austrian breast and colorectal cancer study group trial 6.

PURPOSE: To determine whether the addition of aminoglutethimide to tamoxifen is able to improve the outcome in postmenopausal patients with hormone receptor-positive, early-stage breast cancer. PATIENTS AND METHODS: A total of 2,021 postmenopausal women were randomly assigned to receive either tamoxifen for 5 years alone or tamoxifen in combination with aminoglutethimide (500 mg/d) for the first 2 years of treatment. Tamoxifen was administered at 40 mg/d for the first 2 years and at 20 mg/d for 3 years. RESULTS: All randomized and eligible patients were included in the analysis according to the intention-to-treat principle. After a median follow-up of 5.3 years, the 5-year disease-free survival in the aminoglutethimide plus tamoxifen group was 83.6% versus 83.7% in the monotherapy group (P =.89). The corresponding data for overall survival at 5 years were 91.4% and 91.2%, respectively (P =.74). More patients failed to complete combination treatment (13.7%) because of side effects as compared to tamoxifen alone (5.2%; P =.0001). CONCLUSION: Aminoglutethimide given for 2 years in addition to tamoxifen for 5 years does not improve the prognosis of postmenopausal patients with receptor-positive, lymph node-negative or lymph node-positive breast cancer.

A phase II study of cisplatin and vinorelbine in patients with metastatic breast cancer.

BACKGROUND: To evaluate the efficacy and safety of the combination of cisplatin and vinorelbine in metastatic breast cancer. PATIENTS AND METHODS: Cisplatin (80 mg/m(2) day 1) and vinorelbine (25 mg/m(2) days 1 and 8) were administrated every 3 weeks to 52 patients (mean age 57 years; range 35-75 years) with metastatic breast cancer. Thirty-two patients were previously untreated for metastatic disease. Treatment was repeated for a maximum of six cycles. RESULTS: Objective responses were obtained in 27 patients (52.9%; complete response 9.8%). The response rate was similar in pretreated and untreated patients (50% and 54.7%, respectively; P = 0.7). ECOG performance status was good (grade 0 or 1) in 55.7% of patients at baseline assessment and in 90.3% at the end of treatment (P = 0.0001). Median time to progression was 8.5 months (8.5 months in first-line and 8.7 months in second-line patients). Median survival was 16.6 months (21.2 months in first-line and 16.1 months in second-line patients). Grade 3/4 toxicity included neutropenia (44% in first-line, 60% in second-line patients), nausea (17.3%), anemia (17%), asthenia (3.8%) and thrombocytopenia (1.9%). There were no cases of febrile neutropenia or treatment-related deaths. Alopecia did not develop in any of the patients. CONCLUSIONS: Cisplatin plus vinorelbine is active and tolerable in metastatic breast cancer, in untreated and pretreated patients.

Elevation of soluble tumor necrosis factor receptor II in non-febrile patients with acute myeloid leukemia.

BACKGROUND: Tumor necrosis factor alpha (TNF) and its cellular and soluble (s) receptors (TNF-R) are important mediators in acute myeloid leukemia (AML) and infectious complications during cytoreductive therapy. We investigated the serum concentrations of sTNF-RII in previously untreated patients with AML at the onset of cytoreductive therapy and in non-febrile chemotherapy-associated neutropenia. PATIENTS AND METHODS: Of 54 eligible patients with AML, serum concentrations of sTNF-RII could be evaluated in 25 non-neutropenic, non-febrile and in 11 neutropenic, non-febrile patients. RESULTS: At baseline, non-neutropenic, non-febrile AML patients showed high median serum sTNF-RII concentrations of 3,804 pg/mL. In neutropenia, there was a non-significant trend (p = 0.18) to lower median sTNF-RII levels of 3,246 pg/mL. CONCLUSIONS: Serum sTNF-RII concentrations in non-febrile AML patients before chemotherapy are in the range of levels reached in uncomplicated febrile episodes in otherwise healthy individuals. This must be taken into account when evaluating the cytokine profile for sepsis in patients with therapy-associated neutropenia. Concentrations are still elevated in neutropenia, suggesting that a normal number of leukocytes is not necessarily required for the activation of the TNF ligand/TNF receptor system in AML.

Combined endocrine treatment of elderly postmenopausal patients with metastatic breast cancer. A randomized trial of tamoxifen vs. tamoxifen + aminoglutethimide and hydrocortisone and tamoxifen + fluoxymesterone in women above 65 years of age.

The efficacy of combined endocrine therapy with tamoxifen (TAM), aminoglutethimide (AG), and hydrocortisone (H) or tamoxifen and fluoxymesterone (FLU) was evaluated against treatment with tamoxifen alone in 311 patients above 65 years of age with a first recurrence of a metastatic breast cancer. A total of 279 patients were eligible. The response rates were assessed for 258 fully evaluable patients and were the following for the TAM (N = 94), the TAM+AG+H (N = 83), and the TAM+FLU (N = 81) groups, respectively, PR: 14, 18, and 21%, and CR: 20, 11, and 23%. The overall response rates are not statistically different (p = 0.30). The 95% CL of difference in response rates for TAM vs. TAM+AG+H are -9-19% and for TAM vs. TAM+FLU -4-25%. Time to treatment failure was comparable with median values of 9.2, 7.7, and 9.2 months in the TAM, TAM+AG+H, and TAM + FLU group, respectively (p = 0.17). The corresponding figures for survival are median times of 22.0, 24.1, and 21.1 months with a p-value of 0.62. Toxicity was more pronounced in both the combined treatment groups, and could in most instances be attributed to treatment with either AG+H or FLU. Currently, new specific aromatase inhibitors with lesser toxicity than AG are being evaluated in combination with TAM for treatment of primary and metastatic breast cancer. In conclusion, the simultaneous use of TAM and AG +H or FLU does not seem to improve the therapeutic efficacy in elderly postmenopausal patients with metastatic disease. So far, combined endocrine therapy in this group of patients should only be used in the context of clinical trials.

Prognosis in adult AML is precisely predicted by the DISC-assay using the chemosensitivity-index Ci.

We prospectively investigated the correlation between DISC-assay results and clinical response and also survival in patients with AML using a new method of evaluation.

Long-term medical treatment of ectopic ACTH syndrome.

BACKGROUND: The morbidity of hypercortisolemia due to ectopic production of ACTH by various tumors may be greater than the morbidity of the tumor itself. METHODS: We report three cases of long-term treatment of ectopic ACTH syndrome due to metastatic bronchial carcinoid, islet cell carcinoma, and malignant thymoma tumors. Clinical and biochemical eucortisolemia was achieved in each case and was sustained from 24 to 55 months. We review the therapeutic options and their reported efficacy. RESULTS: Cessation of therapy resulted in recurrence of hypercortisolemia in each case, showing the effectiveness of therapy. CONCLUSION: Long-term treatment of ectopic ACTH-induced hypercortisolemia by blocking adrenal steroidogenesis is clinically effective and well tolerated.

Letrozole, a new oral aromatase inhibitor: randomised trial comparing 2.5 mg daily, 0.5 mg daily and aminoglutethimide in postmenopausal women with advanced breast cancer. Letrozole International Trial Group (AR/BC3).

BACKGROUND: The study compares letrozole and aminoglutethimide (AG), a standard therapy for postmenopausal women with advanced breast cancer, previously treated with antioestrogens. PATIENTS AND METHODS: 555 women were randomly assigned letrozole 2.5 mg once daily (n = 185), letrozole 0.5 mg once daily (n = 192) or aminoglutethimide 250 mg twice daily with corticosteroid support (n = 178) in an open-label, multicentre trial. The primary endpoint was objective response rate (ORR), with time events as secondary. ORR was analysed nine months after enrollment of the last patient, while survival was analysed 15 months after the last patient was enrolled. We report the results of these analyses plus an extended period of observation (covering a total duration of approximately 45 months) to determine the duration of response and clinical benefit. RESULTS: Overall objective response rates (complete + partial) of 19.5%, 16.7% and 12.4% were seen for letrozole 2.5 mg, 0.5 mg and AG respectively. Median duration of response and stable disease was longest for letrozole 2.5 mg (21 months) compared with letrozole 0.5 mg (18 months) and AG (14 months). Letrozole 2.5 mg was superior to AG in time to progression, time to treatment failure and overall survival. Treatment-related adverse events occurred in fewer patients on letrozole (33%) than on AG (46%). Transient nausea was the most frequent event with letrozole (7% on 0.5 mg, 10% on 2.5 mg, 10% on AG), rash with AG (11%, 1% on 0.5 mg, 3% on 2.5 mg letrozole). CONCLUSIONS: Letrozole 2.5 mg offers longer disease control than aminoglutethimide and letrozole 0.5 mg in the treatment of postmenopausal women with advanced breast cancer, previously treated with anti-oestrogens.

Phase II study of suramin plus aminoglutethimide in two cohorts of patients with androgen-independent prostate cancer: simultaneous antiandrogen withdrawal and prior antiandrogen withdrawal.

Management of prostate cancer progression after failure of initial hormonal therapy is controversial. Recently, the activity of the simple discontinuation of antiandrogen therapy has been established by several groups, as well as the enhanced activity when combined with adrenal suppression (i.e., aminoglutethimide and hydrocortisone). Furthermore, suramin has generated considerable interest following reports of response rates ranging from 17 to 70%. More recently, suramin response rates of 18 and 22% have been reported when the potential confounding variables of flutamide withdrawal and hydrocortisone were prospectively controlled. On the basis of the activity of combining aminoglutethimide with flutamide withdrawal, we designed a protocol in which suramin was combined with aminoglutethimide in two cohorts of patients (those with simultaneous antiandrogen withdrawal compared to those who had previously discontinued antiandrogen therapy). Eighty-one evaluable patients were enrolled in this study between June 1992 and November 1994. Patients were a priori divided into two cohorts, those receiving prior antiandrogen withdrawal (n = 56) and those receiving simultaneous antiandrogen withdrawal (n = 25) at the time the patients were enrolled into the trial. For the group that discontinued antiandrogen prior to enrolling in therapy, the partial response rate (> 50% decline in PSA for > 4 weeks) was 14.2%, whereas the partial response was 44% for those patients who discontinued their antiandrogen at the time of starting suramin and aminoglutethimide. The median time to progression was 3.9 months in patients failing prior antiandrogen withdrawal and 5.5 months in those patients having concomitant antiandrogen withdrawal (P = 0.36 for the overall difference). The progression-free survival estimate at 1 year for patients having prior antiandrogen withdrawal was 19.8% [95% confidence interval (CI), 11-32.9%]. For those patients who experienced antiandrogen withdrawal simultaneous with the treatment, the progression-free survival estimates at 1 and 2 years were 27.1 (95% CI, 13.2-47.6%) and 4.5% (95% CI, 0.8-21.6%). The median survival time for those patients having prior antiandrogen withdrawal was 14.2 months, whereas the median survival was 21.9 months for those having concomitant antiandrogen withdrawal (P = 0.029 for the overall difference). In conclusion, the partial response rate of 44% for those who had concomitant flutamide withdrawal with adrenal suppression was consistent with that of other reports using a similar maneuver. Although this study was not randomized and thus we should not over-interpret the results, flutamide withdrawal plus adrenal suppression appears to have greater activity than flutamide withdrawal alone. Furthermore, these data suggest that suramin adds little to the response rate observed for other adrenal suppressive agents in the presence of antiandrogen withdrawal. This interpretation is in agreement with those studies controlling for adrenal suppression and flutamide withdrawal prior to suramin administration, which noted modest activity of short duration. Given that antiandrogen withdrawal is now accepted as an active maneuver for a subset of patients progressing after maximum androgen blockade, we propose that future trials attempting to maximize response rates incorporate this maneuver whenever possible into prospectively designed regimens.

Megestrol acetate and aminoglutethimide/hydrocortisone in sequence or in combination as second-line endocrine therapy of estrogen receptor-positive metastatic breast cancer: a Southwest Oncology Group phase III trial.

PURPOSE: A phase III randomized trial was performed to determine whether combination hormonal therapy with aminoglutethimide (AG) and hydrocortisone (HC) plus megestrol acetate (MA) improved response rates, response duration, or increased survival over the sequential use of each hormone in women with estrogen receptor-positive metastatic breast cancer (MBC) who had maintained stable disease for at least 6 months or responded to tamoxifen. PATIENTS AND METHODS: Two hundred eighty-eight postmenopausal women with progressive estrogen receptor-positive MBC were randomly selected to receive MA 40 mg four times daily (arm I), AG 250 mg four times daily with HC 40 mg daily in divided doses (arm II), versus the combination of MA plus AG given at the same dosages (arm III). Patients on arms I and II who progressed after an adequate trial were crossed over to the other treatment arm. RESULTS: Two hundred thirty-five eligible patients were evaluated for response, time to treatment failure, and survival. Response was only reported for patients with measurable disease and was not statistically different among the three arms. There were two partial responses (PRs) on MA (6%), four complete responses (CRs) and six PRs on AG (24%), and eight PRs and three CRs on MA plus AG (23%) in 32, 42, and 48 measurable patients, respectively. Median times to treatment failure were also similar at 5, 4, and 7 months. Survival was also not statistically different among the three arms at 26, 27, and 26 months for arms I, II, and III, respectively. Toxicity was greater in the two AG arms with respect to fatigue, nausea and vomiting, and rash. CONCLUSION: With the exception of toxicity, there is no response, time to treatment failure, or survival benefit for any one group when comparing MA, AG, or the combination at their stated doses in women with estrogen receptor-positive MBC who had previously responded to or stabilized with tamoxifen.

Primary systemic therapy for operable breast cancer--10-year survival data after chemotherapy and hormone therapy.

Between 1984 and 1990, 94 women presenting to the Edinburgh Breast Unit with operable breast cancer of 4 cm or greater in diameter (T2, T3, N0, N1, M0) were given preoperative systemic therapy. Initially, all women received hormone therapy, with CHOP (cyclophosphamide 1 g m(-2), doxorubicin 50 mg m(-2), vincristine 1.4 mg m(-2) to a maximum of 2 mg and prednisolone 40 mg per day orally for 5 days) chemotherapy being administered to those who failed to respond by 3 months. After April 1987, first-line hormone therapy was only offered to women with oestrogen receptor (ER)-moderate/-rich (> 20 fmol mg(-1) protein) tumours, and CHOP was reserved for those women whose tumours failed to respond to hormone therapy and for those with ER-negative/-poor tumours. Response data have been published previously (Anderson et al, 1991). After a median follow-up of 7.5 years, there is no difference in survival between those women given initial hormone therapy and those given chemotherapy, with neither group having yet reached its median survival. The two key factors that predicted for a poor survival were the number of involved axillary nodes after preoperative systemic therapy (P < 0.00001) and a lack of response to preoperative therapy (P < 0.05). These data suggest that many women with ER-moderate/-rich tumours will have a good prognosis after preoperative hormone therapy alone. However, it is possible to identify, by their post-systemic therapy axillary node status, a group of women who still have an appalling prognosis after preoperative chemotherapy or hormone therapy.

Third-line hormonal treatment with exemestane in postmenopausal patients with advanced breast cancer progressing on aminoglutethimide: a phase II multicentre multinational study. Exemestane Study Group.

In a European multicentre phase II study, 80 postmenopausal patients (pts) with advanced breast cancer progressing on aminoglutethimide (AG) at daily doses of > or = 500 mg were enrolled. Seventy-eight received exemestane (200 mg daily orally), including 33 pts resistant to prior AG, 39 pts who had progressed after an initial response to AG, and 6 pts whose response to AG was either unavailable or not evaluable. Three pts were pretreated with AG only, 69 with tamoxifen and AG, and 6 with tamoxifen, AG and other hormone therapies; 55% had also previously received chemotherapy. The predominant site of disease was visceral in 34 cases, bone in 27 and soft tissue in 17. Based on Peer Review assessment, the overall objective response rate (CRs plus PRs) was 26% (12% in pts resistant to AG and 33% in AG-responsive pts). Disease stabilisation > or = 24 weeks was achieved in an additional 13% of patients (15% of those resistant to AG and 13% of those AG-responsive), resulting in an overall success rate of 39% (28-50, 95% confidence interval). The median duration of objective response, overall success and median TTP were 59, 48 and 21 weeks, respectively. Toxicities were usually mild to moderate in severity, with hot flushes (21%), nausea (19%), dizziness (12%), weakness (12%), increased sweating (12%), androgenic symptoms (10%) and peripheral oedema (9%) as the most common side-effects. Only 2 pts (3%) discontinued treatment due to adverse events. These results are very promising considering that exemestane was administered as third- or fourth-line hormonal treatment in most cases and confirm previous observations about the lack of cross-resistance when steroidal aromatase inhibitors are sequenced with the non-steroidal aromatase inhibitor AG.

Treatment with formestane alone and in combination with aminoglutethimide in heavily pretreated breast cancer patients: clinical and endocrine effects.

We studied the clinical and endocrine effects of the aromatase inhibitor formestane (4-hydroxyandrostenedione, 4-OHA) in heavily pretreated breast cancer patients (median number of previous endocrine treatments 2, range 1-4). Of 30 patients eligible for response evaluation, 3 patients (10%) showed a partial response while 11 patients (36.7%) experienced stable disease over a time period of at least 6 months. Plasma levels of oestrone, oestradiol and oestrone sulphate were found suppressed to a mean of 33.9, 35.6 and 24.2% of control values. 4 of 6 patients experienced a further substantial reduction in plasma oestrone sulphate to < 5% of pretreatment values when aminoglutethimide (AG) was added after relapse on 4-OHA monotherapy. Our findings suggest that these aromatase inhibitors may suppress plasma oestrogen levels by a percentage approaching the percentage inhibition of in vivo aromatisation measured by tracer techniques.