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C K Osborne

Publications and source records attributed to C K Osborne.

At least 55 records · Page 3Linked to original sources
PubMed1998

Survival advantage of adjuvant chemotherapy in high-risk node-negative breast cancer: ten-year analysis--an intergroup study.

PURPOSE: Preliminary analysis showed that adjuvant chemotherapy is effective in improving disease-free survival (DFS) among high-risk breast cancer patients. This report updates the analysis of the high-risk group and reports the results of the low-risk group. METHODS: Patients who had undergone a modified radical mastectomy or a total mastectomy with low-axillary sampling, with negative axillary nodes and either an estrogen receptor-negative (ER-) tumor of any size or an estrogen receptor-positive (ER+) tumor that measured > or = 3 cm (high-risk) were randomized to receive six cycles of cyclophosphamide, methotrexate, fluorouracil, and prednisone (CMFP) or no further treatment. Patients with ER+ tumors less than 3 cm (low-risk) were monitored without therapy. RESULTS: DFS and overall survival (OS) at 10 years were 73% and 81%, respectively, among patients who received chemotherapy, as compared with 58% and 71% in the observation group (P=.0006 for DFS and P=.02 for OS). Chemotherapy was beneficial for patients with large tumors, both ER+ and ER-, showing a 10-year DFS of 70% versus 51 % (P=.0009) and OS of 75% versus 65% (P=.06). Ten-year survival was 77% among low-risk patients, 85% among premenopausal patients, and 73% in the postmenopausal group. CONCLUSION: The observed 37% reduction in risk of recurrence and 34% reduction in mortality risk at 10 years, associated with a 15.4% absolute benefit in disease-free state and 10.1% in survival, reaffirm the role of adjuvant chemohormonal therapy in the management of high-risk node-negative breast cancer. Tumor size remains a significant prognostic factor associated with recurrence and survival in the low-risk group.

Adult↗
PubMed1998

Multicenter randomized clinical trial of goserelin versus surgical ovariectomy in premenopausal patients with receptor-positive metastatic breast cancer: an intergroup study.

PURPOSE: To compare failure-free survival (FFS) and overall survival (OS) for patients with metastatic breast cancer treated with the gonadotropin-releasing hormone (GN-RH) agonist, goserelin versus surgical ovariectomy. PATIENTS AND METHODS: Between August 1, 1987 and July 15, 1995 138 (136 eligible) premenopausal patients with estrogen receptor (ER)- and/or progesterone receptor (PgR)-positive metastatic breast cancer were entered by the Southwest Oncology Group (SWOG), North Central Cancer Treatment Group (NCCTG), and Eastern Cooperative Oncology Group (ECOG). Prior chemotherapy or hormone therapy for metastatic disease was not allowed. Patients were randomly assigned to goserelin (3.6 mg subcutaneously every 4 weeks; (n = 69) versus surgical ovariectomy (n = 67). The study was initially designed as an equivalence trial with 80% power to rule out a 50% improvement in survival due to ovariectomy. However, accrual was slow and the study was terminated early, which resulted in a final power of 60% for the alternative hypothesis of equal survival distributions. RESULTS: FFS and OS were similar for goserelin and ovariectomy. The goserelin/ovariectomy death hazards ratio was .80 and the associated 95% confidence interval (CI) was .53 to 1.20. The test of 50% improvement in survival due to ovariectomy was rejected at P = .006. Goserelin lowered serum estradiol to postmenopausal levels. Hot flashes (75% v 46%) and tumor flare (16% v 3%) were more common with goserelin. CONCLUSION: Goserelin and ovariectomy resulted in similar FFS and OS. We can rule out a moderate advantage for ovariectomy. Goserelin was safe and well tolerated.

Adult↗
PubMed1998

Radiation therapy and survival in breast cancer patients with 10 or more positive axillary lymph nodes treated with mastectomy.

PURPOSE: Adjuvant loco-regional radiation (XRT) frequently is recommended after mastectomy and adjuvant systemic therapy in patients with 10 or more positive axillary lymph nodes (ALN) to reduce the high loco-regional failure rate observed in this subset. In this study, we explored the possibility that adjuvant loco-regional radiation therapy (LR-XRT) also could decrease distant failure and improve overall survival (OS) in this subset of poor-prognosis patients. PATIENTS AND METHODS: Retrospectively, 618 breast patients with 10 or more positive ALN were studied. The median follow-up time was 7.5 years. All patients received systemic adjuvant therapy and 35% also received adjuvant radiation therapy. Loco-regional failure, distant failure, and OS analyses were adjusted for age, tumor size, number of positive ALN, and estrogen receptor (ER) status using Cox regression model. RESULTS: As expected, patients had a very high risk of loco-regional and distant failure. At 5 years, 30% of patients had loco-regional failure as a first event and 54% had distant failure. Radiation dramatically reduced loco-regional failure (hazards rate ratios [RR]=0.29; 95% confidence interval [CI], 0.19 to 0.45). The adjusted 5-year loco-regional failure rate was 13% with radiation and 38% without radiation (P=.0001). Radiation also was associated with improved distant control (RR=0.75; 95% CI, 0.58 to 0.96). The adjusted 5-year distant failure rate was 48% with radiation and 58% without radiation (P=.02). OS also improved with radiation (RR=0.68; 95% CI, 0.53 to 0.85). The adjusted 5-year OS was 56% with radiation and 42% without radiation (P=.001). CONCLUSION: In this cohort of high-risk breast cancer patients, XRT was associated with less loco-regional and distant failure and improved OS. This suggests that improved loco-regional control might decrease secondary systemic spread and improve survival.

Adult↗
PubMed1998

Eastern Cooperative Oncology Group randomized trials of observation versus maintenance therapy for patients with metastatic breast cancer in complete remission following induction treatment.

PURPOSE: To investigate the value of maintenance treatment for patients with metastatic breast cancer whose disease is in complete remission (CR). PATIENTS AND METHODS: One hundred ninety-five women (141 eligible) whose disease was in CR or in CR except for bone metastases following six cycles (6 months) of doxorubicin-containing induction treatment were randomized to receive cyclophosphamide, methotrexate, fluorouracil, prednisone, tamoxifen, and halotestin [CMF(P)TH] or observation. In a previous pilot study, patients in CR after 24 months of induction treatment were randomized to continue chemotherapy for 4 more years or stop chemotherapy. RESULTS: Among patients randomized to CMF(P)TH, life-threatening toxicity included leukopenia in 3%, thrombocytopenia in 3%, cardiac in 2%, and diabetes in 1%. The median time to relapse from randomization was 18.7 months on CMF(P)TH and only 7.8 months on observation (P < .0001). The median time to death was 32.2 months on CMF(P)TH and 28.7 months on observation (P=.74). Similar results were seen in the pilot study (median time to relapse, 12.6 and 6.4 months; median survival, 37.7 and 24.2 months; study too small for statistical significance). Maintenance treatment was always the most significant covariate in time-to-relapse models. CONCLUSION: There is definite toxicity associated with CMF(P)TH maintenance treatment. When CR was obtained on induction, maintenance treatment with CMF(P)TH was never significant in survival models. However, maintenance treatment was always the most significant covariate in the time-to-relapse models, which motivates its consideration for appropriately informed patients.

Adult↗
PubMed1998

Sixteen-week multidrug regimen versus cyclophosphamide, doxorubicin, and fluorouracil as adjuvant therapy for node-positive, receptor-negative breast cancer: an Intergroup study.

PURPOSE: The Intergroup conducted this breast cancer adjuvant trial to compare an investigational 16-week regimen with cyclophosphamide, doxorubicin, and fluorouracil (5-FU; CAF). The 16-week regimen features greater doxorubicin and 5-FU dose-intensity than CAF and improved scheduling of antimetabolites with sequential methotrexate and 5-FU, as well as infusion 5-FU. PATIENTS AND METHODS: A total of 646 node-positive, receptor-negative patients were randomly assigned to receive either the 1 6-week regimen or six cycles of CAF. Breast cancer outcomes included recurrence as well as disease-free and overall survival. Toxicity was evaluated by the Common Toxicity Criteria (CTC). Treatment-related quality of life was assessed by the Breast Chemotherapy Questionnaire (BCQ) before, during, and 4 months after treatment in 163 patients. The trial was designed to use one-sided tests of significance for power calculations, but is now reported with both one-sided and the traditional two-sided tests of significance. RESULTS: At a median follow-up of 3.9 years, the estimated 4-year recurrence-free survival rate was 67.5% with the 16-week regimen versus 62.7% with CAF (P = .19, two-sided; P = .095, one-sided). The estimated 4-year survival rate was 78.1% with the 16-week regimen versus 71.4% with CAF (P = .10, two-sided; P = .05, one-sided). CAF produced significantly higher grades of leukopenia, granulocytopenia, and thrombocytopenia, as well as liver and cardiac toxicity, whereas the 16-week regimen produced significantly higher grades of anemia, nausea, stomatitis, and weight loss, as well as skin and neurotoxicity. There were three treatment-related deaths with CAF but none with the 16-week regimen. During treatment, quality of life declined significantly more with the 16-week regimen than CAF, but by 4 months posttreatment, there was no difference. CONCLUSION: The 16-week regimen produced marginally better breast cancer outcomes than CAF with similar toxicity but a greater reduction in during-treatment quality of life. The 16-week regimen should not be used instead of a standard-dose regimen without careful consideration of the 16-week regimen's pros and cons, which include its complicated schedule. It should probably not be tested further, but its antimetabolite schedules and frequent drug administration (ie, dose density) should be considered in the development of new regimens.

Adult↗
PubMed1998

HER-2 expression and response to tamoxifen in estrogen receptor-positive breast cancer: a Southwest Oncology Group Study.

HER-2/neu is a growth factor receptor, the expression of which has been associated with a more aggressive breast tumor biology and resistance to some types of chemotherapy. Preliminary laboratory and clinical data have led to claims that HER-2/neu expression is also associated with resistance to tamoxifen. Therefore, to test the hypothesis that HER-2/neu expression is associated with a poorer response to tamoxifen, a shorter time to treatment failure (TTF), and worse survival in estrogen receptor (ER)-positive metastatic breast cancer, we examined 205 paraffin-embedded blocks of tumors from patients enrolled on Southwest Oncology Group 8228 for HER-2/neu expression. Tumors were ER positive (ER level > 3 fmol/mg cytosolic protein in either primary tumors or metastases), and patients had not received any prior therapy for metastatic disease. All patients were treated with daily tamoxifen. The study began in 1982, and median follow-up of patients who are still alive is now 9 years. Membrane staining for HER-2/neu was evaluated by immunohistochemistry using antibody TAB 250 and was scored according to the proportion of cells staining positive; tumors were deemed positive if > 1% of the cells stained for HER-2/neu. HER-2/neu positivity was associated with lower ER values (P = 0.04) and low bcl-2 (P = 0.01). HER-2/neu positivity was not significantly associated with response rate (negative versus positive, 57 versus 54%; P = 0.67), TTF (median, 8 versus 6 months; P = 0.15), or survival (median, 31 versus 29 months; P = 0.36). There was also no significant evidence of a progressive relationship between an increasing proportion of cells expressing HER-2/neu and a shorter TTF or survival. HER-2/neu expression in ER-positive metastatic breast cancer is not significantly associated with a poorer response to tamoxifen or a more aggressive clinical course. Earlier suggestions to the contrary may have been due to failure to rigorously exclude ER-negative tumors, which are much less likely to respond to tamoxifen and more likely to have high HER-2/neu levels.

Adult↗
PubMed1998

Heat shock proteins hsp27 and hsp70: lack of correlation with response to tamoxifen and clinical course of disease in estrogen receptor-positive metastatic breast cancer (a Southwest Oncology Group Study).

In this study, we tested the hypothesis that heat shock proteins (hsps) 27 and 70 are associated with clinical resistance to tamoxifen. hsp27 is, like progesterone receptor, an estrogen-regulated protein. hsp70 is also of interest because of its interaction with estrogen receptors and because hsp70 is a component of the molecular chaperone machinery functioning in the assembly and trafficking of steroid receptors. In addition, hsps in general help protect cells against noxious stimuli and stress, and their expression has been linked to drug resistance. The study involved 205 tumors from estrogen receptor-positive tamoxifen-treated breast cancer patients with metastatic disease. All patients received daily tamoxifen as initial therapy for metastatic disease. The study began in 1982, and follow-up is now 9 years. hsp27 and hsp70 were detected by immunohistochemistry and scored according to the nuclear and/or cytoplasmic content. Expression of hsp27 or hsp70 was unrelated to estrogen receptor content, progesterone receptor content, menopausal status, age, and presence of visceral disease. Cytoplasmic and nuclear hsp27 positivities were weakly and inversely related to each other (P = 0.05). There was a significant association between cytoplasmic hsp27 and cytoplasmic hsp70 content (P < 0.001), as well as between nuclear hsp70 and nuclear hsp27 content (P = 0.001). Cytoplasmic and nuclear hsp70 were also associated (P = 0.02). However, increased hsp27 and hsp70 expression (nuclear or cytoplasmic) was not significantly associated with response to tamoxifen, time to treatment failure, or survival. Thus, this study clarifies the lack of clinical utility of hsp27 and hsp70 in predicting the response to tamoxifen in an estrogen receptor-positive breast cancer population.

Adult↗
PubMed1997

Telomerase activity and survival of patients with node-positive breast cancer.

BACKGROUND: Shortening of telomeres (specialized structures at the ends of chromosomes) beyond a certain length may signal a cell to stop dividing and to enter senescence. A ribonucleoprotein enzyme, telomerase, is a key component in maintaining telomere length. Because the majority of cancers express telomerase but most normal somatic tissues do not, we measured the level of telomerase expression in primary breast cancer specimens for correlation with traditional prognostic indicators and disease outcome. METHODS: Telomerase activity was measured in frozen human breast cancer specimens by use of the Telomeric Repeat Amplification Protocol (TRAP) assay. The level of telomerase activity was expressed as total product generated (TPG) and was corrected for specimen cellularity by expressing it as a ratio of TPG to the sample's 28S ribosomal RNA content. RESULTS: A preliminary study of 150 breast cancer specimens demonstrated that telomerase activity correlated with the fraction of cells in S phase of the cell cycle (r(sp) = .23). In a larger prognostic study of 398 tumors from patients with lymph node-positive breast cancer, telomerase expression correlated with S-phase fraction, progesterone receptor level, DNA ploidy, and lymph node status. After correcting for sample cellularity, increasing TPG levels were associated with decreased disease-free survival (P = .041) and overall survival (P = .009) of the patients. The telomerase activity level remained strongly predictive of death (P = .027) and marginally predictive of disease recurrence (P = .08) after adjustment for other prognostic factors. All P values are two-sided. CONCLUSIONS: Telomerase activity in human breast cancers is associated with a more aggressive tumor phenotype in patients.

Adult↗
PubMed1997

Mitosin (a new proliferation marker) correlates with clinical outcome in node-negative breast cancer.

Tumor proliferation rate is an important prognostic factor in breast cancer, and S-phase fraction (SPF), as measured by flow cytometry, is the most clinically validated of several methods for measuring it. However, flow cytometry is not well suited to evaluating the formalin-fixed, paraffin-embedded tumors that are routinely available or to the increasing number of small breast cancers. These and other limitations have motivated research into alternative methods for measuring proliferation, including immunohistochemistry (IHC) against cell cycle-related antigens, which are better suited for the evaluation of small archival tissue samples. Mitosin is a recently described 350 kD nuclear phosphoprotein that is expressed in the late G1, S, G2, and M phases of the cell cycle but not in G0. Using a new monoclonal antibody (14C10), this pilot study evaluated mitosin expression by IHC in a series of 386 node-negative, formalin-fixed, archival breast cancers and correlated the results with several prognostic factors and clinical outcome (median follow-up, 78 months; range 3-214 months). The median and range of mitosin positive cells were 7% and 1-47%, respectively. There was a strong positive correlation between mitosin and SPF (r = 0.57; P = 0.0001), and there were significant negative correlations with estrogen receptor, progesterone receptor, and patient age. Mitosin was not related to overall survival in this pilot study. However, in a univariate cutpoint analysis of disease-free survival (DFS), patients with high levels of mitosin (>9% positive cells) had significantly worse DFS than did patients with lower levels (68% versus 84% at 5 years, respectively). In a multivariate analysis of DFS, large tumor size (>2 cm) and high mitosin were the only independently significant predictors of recurrence (relative risks = 2.47 and 1.72, respectively) in a model containing the additional factors estrogen receptor, progesterone receptor, patient age, and SPF. These preliminary results suggest that mitosin as assessed by IHC may be superior to SPF as a prognostic factor in node-negative breast cancer, but additional studies are necessary to validate these promising findings.

Animals↗
PubMed1997

Comparison of estrogen receptor DNA binding in untreated and acquired antiestrogen-resistant human breast tumors.

Preliminary studies have suggested that measuring the ability of immunoreactive 67-kDa estrogen receptor (ER) to bind DNA and form in vitro complexes with its cognate estrogen response element (ERE) might serve to identify breast tumors most likely to respond to antiestrogens like tamoxifen. Data from two different surveys of untreated primary breast tumors confirmed that only 67% (74 of 111) of ER-positive tumors express a receptor capable of forming ER-ERE complexes by gel-shift assay, with tumors of lower ER content having significantly reduced ER DNA-binding frequency (56%) relative to those of higher ER content (82%; P = 0.007). In contrast to these untreated tumors, a panel of 41 receptor-positive breast tumors excised after acquiring clinical resistance to tamoxifen during either primary (n = 26) or adjuvant therapy (n = 15) showed a significantly greater ER DNA-binding frequency, with nearly 90% capable of forming ER-ERE complexes (P < 0.02). To assess experimentally whether ER DNA-binding function is altered during the development of antiestrogen resistance, nude mouse MCF-7 tumor xenografts were analyzed before and after the acquisition of in vivo resistance to either tamoxifen or a pure steroidal antiestrogen, ICI 182,780. Tamoxifen-resistant MCF-7 tumors retained full expression of 67-kDa DNA-binding ER, and despite a markedly reduced ER content in the ICI 182,780-treated tumors, the expressed ER in these antiestrogen-resistant tumors exhibited full ability to form ER-ERE complexes. These findings indicate that breast tumors with acquired antiestrogen resistance continue to express ER of normal size and DNA-binding ability and suggest that the failure of antiestrogens to arrest tumor growth during emergence of clinical resistance results from an altered gene-regulatory mechanism(s) other than ER-ERE complex formation.

Animals↗
PubMed1997

Polyethylene glycol conjugated insulin-like growth factor binding protein-1 (IGFBP-1) inhibits growth of breast cancer in athymic mice.

Insulin-like growth factor (IGF) binding protein-1 (BP-1) inhibits IGF-mediated proliferation of some breast cancer cell lines in vitro. Here we examined whether recombinant human wild-type IGFBP-1 (WT-BP-1) and IGFBP-1 conjugated with polyethylene glycol (PEG-BP-1) could inhibit breast cancer growth. Three breast cancer cell lines were used: MCF-7, MDA-MB-231 and MDA-MB-435A (ascites model). The cells were grown in agar with or without the BP-1 conjugates to investigate their effect on colony formation. Both WT-BP-1 and PEG-BP-1 inhibited anchorage-independent growth (AIG) of MCF-7 and MDA-MB-435A cells. AIG of MDA-MB-231 cells was not inhibited by PEG-BP-1, whereas WT-BP-1 significantly stimulated colony number. We also tested both forms of BP-1 in xenograft tumour models. Two solid breast tumour models were studied using MCF-7 and MDA-MB-231 cell lines, and one ascites model using the MDA-MB-435A cell line. PEG-BP-1 inhibited malignant ascites formation in the MDA-MB-435A model. Conversely, PEG-BP-1 did not significantly inhibit MCF-7 xenograft growth. However, the MDA-MB-231 tumour growth curves were significantly different by a constant amount, suggesting that PEG-BP-1 treatment inhibited early tumour growth of this cell line. In contrast, WT-BP-1 was ineffective in the MDA-MB-231 tumours. These data show that anti-IGF strategies can be used to inhibit breast cancer cell growth. Since PEG-BP-1 inhibited the in vivo, but not in vitro, growth of MDA-MB-231, we speculate that PEG-BP-1 may block host IGF functions required for optimal tumorigenesis. Because PEG-BP-1 has a prolonged serum half-life compared to WT-BP-1, we conclude that improvements in BP-1 pharmacological properties enhanced its antitumour effects in vivo.

Analysis of Variance↗
PubMed1997

Cytological evaluation of biological prognostic markers from primary breast carcinomas.

This study was undertaken to evaluate our ability to detect multiple molecular markers of prognosis and response to treatment in fine needle aspirates (FNA) from patients with primary breast carcinomas. 147 patients with operable primary breast carcinomas who had been recruited to a randomized trial of primary medical therapy (PMT) versus adjuvant chemoendocrine therapy were analysed. FNAs were taken prior to therapy and from this multiple slides were produced using cytospin cytocentrifugation and stored at -80 degrees C for subsequent immunocytochemical analysis (ICA). ICA was performed for oestrogen receptor (ER), progesterone receptor (PgR), p53, Ki67, and Bcl-2. Part of the aspirate was snap frozen and used for flow cytometric analysis of ploidy and S-phase fraction (SPF). In a subgroup of 50 patients who had surgery prior to systemic therapy, as well as FNAs, sections were also taken from paraffin-embedded blocks and stained by ICA for ER, PgR and p53 for validation. In these patients ER was additionally measured by enzyme immunoassay (EIA) from frozen tissue taken at surgery. ER, PgR, p53, Bcl-2, and Ki67 were successfully detected by ICA while ploidy and SPF were successfully measured by flow cytometry from FNA material. The percentage positive values obtained were reasonable and as follows: 74% for ER, 70% for PgR, 36% for p53, 80% for Bcl-2,68% of tumours were aneuploid and 32% diploid. Significant relationships between these measurements were observed in accordance with expectations. The concordance for ER, PgR, and p53 from FNA when compared to ICA of matching histological sections was 91.5%, 75.5%, and 75% respectively. For ER the concordance between measurement by ICA of cytological and histological samples and by EIA of frozen tissue was 82.5% and 84% respectively. These results indicate that multiple molecular markers can be adequately tested on cytological preparations from primary breast tumours. These markers can be used to determine prognosis and predict response to PMT.

Adult↗
PubMed1997

Prognostic significance of PAI-1 and uPA in cytosolic extracts obtained from node-positive breast cancer patients.

Cancer cell invasion is accomplished by the concerted action of several extracellular proteolytic enzyme systems, one of which is the urokinase plasminogen activation system. The different components of this system. e.g. urokinase plasminogen activator (uPA), its receptor uPAR, as well as its main inhibitor plasminogen activator inhibitor type 1 (PAI-1) have all been shown to have prognostic value in breast cancer, i.e. high tumor levels are associated with a poor prognosis. In order to further substantiate the prognostic value of uPA and PAI-1, we have tested the cutpoints (median values and optimized outpoints) from our first study (Cancer Res 53: 2513-2521, 1993) in an independent group of breast cancer patients. Breast cancer cytosols from 100 premenopausal and 150 post-menopausal node positive patients were included. The median observation time was 80 months (range 49-145). Univariate analysis showed that high PAI-1 levels (above the median PAI-1 value) were significantly associated with short recurrence-free survival (RR: 1.65; 95% CI: 1.04-2.63; P = 0.03) and short overall survival (RR: 2.46; 95% CI: 1.52-3.96; P = 0.0001) in postmenopausal patients. Postmenopausal patients with high uPA levels (above the median uPA value) had a significantly shorter recurrence-free survival (RR: 2.04; 95% CI: 1.17-3.56; P = 0.01) and overall survival (RR: 2.07; 95% CI: 1.16-3.70; P = 0.01) than patients with low uPA values. Nearly identical results were obtained when using the optimized PAI-1 or uPA value. In a Cox multivariate analysis which included other established prognostic factors, high PAI-1 was found to be an independent prognostic variable predicting short overall survival with a relative risk of 2.27 in postmenopausal women, and high uPA was found to be an independent prognostic variable predicting short recurrence-free survival with a relative risk of 1.86 in postmenopausal women. The present study indicates that uPA and PAI-1 are independent and significant prognostic variables in subsets of breast cancer patients.

Analysis of Variance↗
PubMed1997

bcl-2, p53, and response to tamoxifen in estrogen receptor-positive metastatic breast cancer: a Southwest Oncology Group study.

PURPOSE: To test the hypothesis that high bcl-2 expression and accumulation of p53 protein, both of which should inhibit apoptosis, are associated with a poorer tamoxifen response and a more aggressive clinical course in estrogen receptor (ER)-positive metastatic breast cancer. METHODS: A total of 205 paraffin-embedded tumor blocks were evaluated for nuclear p53 (a marker of p53 inactivation) and cytoplasmic bcl-2 by immunohistochemistry (IHC). All patients received tamoxifen as initial therapy for metastatic disease. The study began in 1982 and follow-up duration of the 24 patients last known alive is 8 years. RESULTS: Response to tamoxifen and time to treatment failure (TTF) were not significantly associated with p53 status, although patients with higher p53 had a worse survival (P = .008; median, 36 v 20 months). Higher bcl-2 expression was associated with higher levels of ER (P = .02), better response to tamoxifen (62% v 49%; P = .07), longer TTF (median, 9 v 5 months; P = .002), and better survival (median, 40 months v 25 months; P = .009). In multivariate analyses, including ER, progesterone receptor (PgR), and p53, high bcl-2 remained significantly associated with a longer TTF (P = .007) and survival (P = .07). p53 status was a significant factor for shorter survival (P = .05), but not for TTF (P = .61). CONCLUSION: p53 status, as determined by IHC is not significantly associated with response to tamoxifen, although tumors with altered p53 protein are inherently more aggressive. Contrary to expectation, high bcl-2 identifies a relatively indolent phenotype of ER-positive metastatic breast cancer, in which patients experience a better clinical response to tamoxifen and a longer survival.

Adult↗
PubMed1997

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.

Adult↗
PubMed1997

Prediction of response to neoadjuvant chemoendocrine therapy in primary breast carcinomas.

Our aim was to determine whether biological molecular markers can predict response to neoadjuvant chemoendocrine therapy in patients with early breast cancer. Ninety patients (median age 56 years; range, 28-69 years) with primary operable breast carcinoma were studied. They were treated with four 3-weekly cycles of chemotherapy with mitozantrone, methotrexate (+/- mitomycin C), and tamoxifen prior to surgery. Fine-needle aspiration was used to obtain samples from patients prior to therapy, and the following parameters were assessed: estrogen receptor (ER), progesterone receptor (PgR), p53, Ki67, Bcl-2, and c-erbB-2 measured by immunocytochemistry, and ploidy and S-phase fraction (SPF) by flow cytometry. The tumors of 78% of the subjects responded (complete response, 9%; partial response, 69%) and 22% did not (no change, 20%; progressive disease, 2%). Response rates according to disease stage and patient age were as follows: T1, 74%; T2, 79%; T3/T4, 78%; age </=50 years, 76%; >50, 79% (P = not significant). Response rates for other parameters were as follows: ER-positive, 82%, and -negative, 70%; PgR-positive, 86%, and -negative, 71%; p53-positive, 74%, and -negative, 81%; Bcl-2-positive, 85%, and -negative 61%; c-erbB-2-positive, 57%, and -negative, 93%; Ki67 high, 77%, and low, 81%; SPF high, 77%, and low, 77%; aneuploid, 71%; and diploid, 85%. Only the difference for c-erbB-2 was statistically significant (P = 0.007). A trend for higher response rates to neoadjuvant chemoendocrine therapy for tumors that were positive for ER, PgR, and Bcl-2 was observed but did not reach statistical significance. Tumors negative for c-erbB-2 had a higher response rate, which was statistically significant. In contrast, Ki67, ploidy, SPF, and p53 failed to predict for response.

Adult↗