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C K Osborne

Publications and source records attributed to C K Osborne.

At least 109 records · Page 6Linked to original sources
PubMed1993

Pitfalls in quality-of-life assessment: lessons from a Southwest Oncology Group breast cancer clinical trial.

There is increasing interest in evaluating the impact of cancer treatment and medical intervention on patient quality of life (QOL). This article reports the findings of a substudy that incorporated the Functional Living Index--Cancer in an ongoing adjuvant breast cancer clinical trial sponsored by the Southwest Oncology Group. The companion study had to be terminated prior to the end of the two-armed, randomized trial because of poor reporting rates over time. Problems with missing data items also occurred. Poor reporting rates in this trial motivated several recommendations for conducting QOL assessment in the cooperative group setting: (a) build support for QOL assessment among the group's leadership, (b) involve physicians and oncology nurses in the study design, (c) identify a QOL liaison at each participating institution, and (d) aggressively monitor the quality and timeliness of data submission.

Activities of Daily Living↗
PubMed1992

Inhibition of breast cancer cell growth in vitro by a tyrosine kinase inhibitor.

Human breast cancer cell proliferation is regulated by growth factors that bind to receptors with intrinsic tyrosine kinase (TK) activity, including the epidermal growth factor (EGF) receptor. To determine whether inhibition of receptor TK activity inhibits tumor growth, we studied the effects of a tyrosine kinase inhibitor, RG-13022, on cultured human breast cancer cells. RG-13022 represents a class of compounds which have been shown to inhibit preferentially the TK activity of the EGF receptor in a cell-free system and also to inhibit EGF-stimulated growth of cultured cells. RG-13022 significantly inhibited EGF-stimulated autophosphorylation of its receptor in two breast cancer cell lines that have abundant, although not amplified, EGF receptor content (MDA-231 and T47D). RG-13022 also inhibited EGF-stimulated DNA synthesis and proliferation of T47D and MCF-7 breast cancer cells in a reversible and dose-dependent manner. Inhibition was observed at 0.1 microM, and it was maximal at 10 microM. The effect was rapid (within 3 h), persisted for 18 h, and was partially reversed by 24 h at 1 microM. At 5 microM, inhibition persisted for more than 50 h. Inhibitory effects were also observed in a panel of estrogen receptor-positive and estrogen receptor-negative breast cancer cell lines. RG-13022 inhibited not only EGF-induced growth but also growth stimulated by insulin, insulin-like growth factor I, insulin-like growth factor II, or transforming growth factor alpha. RG-13022 also totally blocked estrogen-stimulated phosphorylation of the EGF receptor, as well as estrogen-induced cell proliferation, suggesting that functioning TK pathways are required for estrogen action. The TK inhibitor RG-13022 is a potent inhibitor of hormonally regulated growth of human breast cancer. Tyrosine kinase inhibitors have the potential of providing a new strategy for the "endocrine therapy" of breast cancer.

Breast Neoplasms↗
PubMed1992

Proportional hazards and recursive partitioning and amalgamation analyses of the Southwest Oncology Group node-positive adjuvant CMFVP breast cancer data base: a pilot study.

Several putative prognostic factors have been identified in node-positive breast cancer patients, but their importance needs to be clarified in a uniformly treated population. The objectives of this investigation were: 1) to describe the characteristics of a uniformly treated node-positive data base; 2) to use proportional hazards (Cox) and recursive partitioning and amalgamation (RPA) multivariate models to assess the importance of potential prognostic factors for disease-free and for overall survival; and 3) to define prognostic groups with different disease-free survival and survival outcomes with RPA. A data base of 768 node-positive patients enrolled on 1-year adjuvant CMFVP arms of four SWOG trials was formed. Variables were number of positive nodes, age, age at menopause, menopausal status, ER status, ER and PgR levels (for RPA only), tumor size, race, breast cancer in mother, and obesity index. Independent predictors of both disease-free and overall survival in the Cox models were: number of positive nodes (4-6 worse than 1-3, and better than greater than 6); the age/menopause category (age greater than or equal to 35/premenopausal better than age less than 35/premenopausal and better than postmenopausal); and ER status (patients on ER-negative study worse than others). The RPA for disease-free survival defined four subgroups based on nodes, menopausal status, tumor size, and age at menopause (5-year recurrence-free rates = 73%, 52%, 38%, and 15%). The RPA for survival found four prognostic groups, defined only by the number of positive nodes and ER and PgR levels (5-year survivals = 91%, 72%, 56%, and 37%). Both RPAs suggested interesting refinements of the results of the Cox models. In the RPA for disease-free survival, best node cutoffs differed by menopausal status, tumor size was important only in postmenopausal patients with few positive nodes, and age at menopause emerged as an independent predictor of recurrence potential. And, the RPA for survival showed that node cutoffs differed according to ER level. Thus, these analyses underscore the value of simple, clinically available prognostic factors and suggest the possible need to reconsider the definition of good and poor risk patient groups in future adjuvant trial design.

Adult↗
PubMed1992

Estrogen-dependent, tamoxifen-resistant tumorigenic growth of MCF-7 cells transfected with HER2/neu.

Since the poor prognosis associated with HER2 amplified breast cancers might be explained by a mechanistic association between p185HER2 overexpression and therapeutic resistance, we assessed the chemo-endocrine sensitivity of estrogen receptor (ER) containing MCF-7 breast cancer cells transfected with full-length HER2 cDNA. Of the 36 isolated MCF/HER2 subclones, 7 were found to overexpress p185HER2 surface receptor at levels 3 to 45-fold greater than parental or control transfected cells (MCF/neo). The overexpressing transfectants possessed increased inositol-1,4,5-triphosphate-3'-kinase activity comparable to enzyme activity in the endogenously HER2 amplified breast cancer cell lines SK-Br-3 and BT-474. The anti-p185HER2 monoclonal antibody and receptor-specific partial agonist, muMAb4D5 (4D5), known to inhibit growth of SK-Br-3 and BT-474 cells, produced no significant growth inhibitory effect on any of the transfectants including the 45-fold overexpressing MCF/HER2-18 cells which were studied in greater detail. MCF/HER2-18 cells contained at least partially functioning exogenous receptor since 4D5 (3 micrograms/ml) specifically stimulated phosphorylation of p185HER2 and its co-precipitating ptyr56 substrate within 5 min, and this was followed at 1 h by a transient induction of c-myc but not c-fos mRNA. ER content and the in vitro sensitivity of MCF/HER2-18 cells to 5-fluorouracil and adriamycin were identical to those of control transfectants and parental cells. However, these highly overexpressing transfectants had acquired low level (2 to 4-fold) resistance to cisplatin and were no longer sensitive to the antiestrogen tamoxifen (TAM). To compare the hormone-dependent tumorigenicity of the HER2 transfectants, MCF/HER2-18 and control cells (MCF, MCF/neo-3) were implanted into ovariectomized athymic nude mice. No tumors were produced in the absence of estradiol (E2) administration. In E2 supplemented mice, MCF/HER2-18 tumors grew most rapidly. When E2 treatment was stopped and daily TAM injections were initiated, MCF-7 and MCF/neo-3 tumor growth ceased immediately, while MCF/HER2-18 tumors continued to show an accelerated growth rate lasting weeks. This pattern of hormone-dependent, TAM-resistant growth exhibited by the MCF/HER2-18 tumors in nude mice supports the possibility that p185HER2 overexpression in human breast cancers may be linked to therapeutic resistance.

Adenocarcinoma↗
PubMed1992

Overexpression of HER-2/neu and its relationship with other prognostic factors change during the progression of in situ to invasive breast cancer.

Using permanent-section immunohistochemistry, we investigated the role of HER-2/neu in the development and progression of human breast cancer by measuring its overexpression in a series of hyperplastic (n = 30), dysplastic (n = 15), and malignant neoplastic (n = 708) lesions of ductal epithelium and by evaluating the relationships between overexpression and clinicopathologic features known to have prognostic significance in these lesions. The neoplasms included pure ductal carcinoma in situ (DCIS; n = 59) and infiltrating ductal carcinoma (IDC; n = 649). The latter were all node negative and stratified into IDC combined (n = 237) or not combined (n = 412) with a "significant amount" of DCIS (defined as DCIS greater than or equal to 10% of total tumor cellularity). Overexpression of HER-2/neu was not observed in any of the hyperplastic or dysplastic lesions. In contrast, it was present in 56% of pure DCIS and in 77% of the comedo subtype of this group. Only 15% of IDC overexpressed HER-2/neu. However, the rate of overexpression was significantly higher in the subset of IDC combined with DCIS compared with the subset of IDC not combined with DCIS (22% v 11%, respectively; P less than .0001). These results are consistent with the hypothesis that HER-2/neu plays a more important role in initiation than in progression of ductal carcinomas. They also suggest that overexpression decreases within individual tumors as they evolve from in situ to increasingly invasive lesions or, alternatively, that many invasive carcinomas arise de novo (ie, without progressing through a significant in situ stage) by mechanisms not involving HER-2/neu. In addition, overexpression of HER-2/neu was associated with several poor prognostic features (younger patient age, premenopause, negative estrogen receptor status, negative progesterone receptor status, and high nuclear grade) in the subset of IDC combined with DCIS. With one exception (negative estrogen receptor status) these associations were lost in IDC not combined with DCIS, also suggesting that the role of HER-2/neu changes during the progression of human breast cancer.

Biomarkers, Tumor↗
PubMed1992

Phase II study of platinum and mitoxantrone in metastatic prostate cancer: a Southwest Oncology Group Study.

44 eligible patients with measurable or evaluable metastatic prostate cancer were treated with monthly cycles of cisplatin and mitoxantrone. Good-risk patients received cisplatin 60 mg/m2 intravenously and mitoxantrone 10 mg/m2 intravenously every 4 weeks. The dose in poor-risk patients (elderly or white blood cell count less than 4000/microliters, 4 x 10(9)/l, or extensive prior radiation) was reduced to 8 mg/m2. Toxicity was manageable and consisted primarily of myelosuppression. There were no complete responses and the partial response rate was only 12%. Median progression-free survival was 2.7 months for measurable and 4.1 months for evaluable disease patients. Median survivals were 4.9 and 8.7 months, respectively. This combination has minimal activity in hormone refractory metastatic prostate cancer.

Adenocarcinoma↗
PubMed1992

Tamoxifen and the isomers of 4-hydroxytamoxifen in tamoxifen-resistant tumors from breast cancer patients.

PURPOSE: The antiestrogen tamoxifen is effective in therapy for breast cancer. However, its use is limited by the eventual development of acquired tamoxifen resistance in many patients. The mechanisms responsible for tamoxifen resistance remain unknown; loss of estrogen receptor (ER), selection of hormone-independent breast cancer clones, or alterations in serum tamoxifen levels after long-term use do not explain acquired resistance in most patients. Using an experimental model in which human breast cancer cells develop resistance in athymic mice treated with tamoxifen, we have recently shown that acquired resistance is associated with markedly reduced cellular concentrations of tamoxifen and by isomerization of the trans-4-hydroxy metabolite to the less potent cis isomer. MATERIALS AND METHODS: Using a sensitive high-performance liquid chromatography (HPLC) assay, we have now measured levels of tamoxifen and its major metabolites in a series of 14 tumors from patients treated with tamoxifen. The duration of therapy ranged from 1 month to 6 years. RESULTS: Tumor tamoxifen levels varied over a wide range. Low concentrations were observed in tumors from eight patients, all demonstrating progressive disease at the time of biopsy after a minimum duration of treatment of 6 months. Six tumors had moderate to high tamoxifen levels, two from patients responding to tamoxifen, one from a patient with stable disease, and three from patients with disease progression. Both the cis and trans isomers of the potent antiestrogenic metabolite 4-hydroxy-tamoxifen were detected in 11 tumors. Six tumors had high ratios of the cis to trans isomer (1.10:2.06), all from patients not responding to tamoxifen. The five tumors with low cis:trans ratios included the two tumors from responding patients and three from patients with progression. All but one of the 11 nonresponding patients had either a low tumor tamoxifen level, a high cis:trans ratio, or both. CONCLUSION: This study clearly demonstrates a wide range of tumor tamoxifen levels and accumulation of the less antiestrogenic cis isomer of 4-hydroxytamoxifen in some patients on tamoxifen therapy. Additional study is necessary to determine if these metabolic profiles are related to the development of tamoxifen resistance.

Adult↗
PubMed1992

Prognostic significance of S-phase fraction in good-risk, node-negative breast cancer patients.

PURPOSE: Formalin-fixed, paraffin-embedded tissues from axillary node-negative breast cancer patients were analyzed by flow cytometry to determine the prognostic significance of DNA ploidy and S-phase fraction (SPF). PATIENTS AND METHODS: All patients were registered on a good-risk control arm of an intergroup clinical trial. They had small- to intermediate-sized (less than 3 cm), estrogen receptor (ER)-positive tumors and received no adjuvant therapy after modified radical mastectomy or total mastectomy with low axillary-node sampling. The median follow-up was 4.8 years. RESULTS: Assessable ploidy results were obtained from 92% of the 298 specimens studied (51% diploid, 49% aneuploid), and SPFs were assessable for 83% of the tumors. SPFs for diploid tumors ranged from 0.7% to 11.9% (median, 3.6%), compared with a range of 1.2% to 26.7% (median, 7.6%) for aneuploid tumors (P less than .0001). No significant differences in disease-free or overall survival were observed between patients with diploid and aneuploid tumors. Using different SPF cutoffs by ploidy status (4.4% for diploid, 7.0% for aneuploid), patients with low SPFs had significantly longer disease-free survival rates than patients with high SPFs (P = .0008). The actuarial 5-year relapse rates were 15% and 32% for patients with low (n = 142) and high SPFs (n = 105), respectively. Similar relationships between SPF and clinical outcome were observed for patients with diploid tumors (P = .053) and for patients with aneuploid tumors (P = .0012). CONCLUSION: S-phase fraction provides additional prognostic information for predicting disease-free survival for axillary node-negative breast cancer patients with small, ER-positive tumors.

Actuarial Analysis↗
PubMed1992

HER-2/neu in node-negative breast cancer: prognostic significance of overexpression influenced by the presence of in situ carcinoma.

PURPOSE: Amplification and/or overexpression of the HER-2/neu oncogene have been shown to correlate with poor clinical outcome in patients with axillary node-positive breast cancer. In contrast, the prognostic significance of HER-2/neu in node-negative disease is controversial. This study was undertaken to evaluate further the relationship between HER-2/neu and clinical outcome in node-negative disease. PATIENTS AND METHODS: Overexpression of HER-2/neu was evaluated by permanent-section immunohistochemistry in tumors from 613 patients with long-term clinical follow-up enrolled in the Intergroup Study 0011. Patients were stratified into low-risk (n = 307) and high-risk (n = 306) groups on the basis of tumor size and estrogen-receptor (ER) status. Low-risk patients were defined as having small (less than 3 cm), ER-positive tumors and were observed without additional treatment after initial surgery. High-risk patients had either ER-negative or large (greater than or equal to 3 cm), ER-positive tumors and were randomized to be observed (n = 146) or to receive adjuvant chemotherapy (n = 160) after surgery. RESULTS: The rate of HER-2/neu overexpression was 14.3% in all tumors combined and was higher in invasive carcinomas with (21.5%) than without (11.2%) a significant noninvasive or in situ histologic component (P less than .0001). There was no relationship between overexpression and clinical outcome in the natural history setting of combined low-risk and high-risk patients not receiving adjuvant therapy (n = 453). Based on the reasoning that the influence of HER-2/neu may have been obscured by high-risk features and/or the presence of noninvasive carcinoma, we also analyzed the subset of patients with low-risk lesions not containing a significant in situ component (n = 179). Patients of this group with HER-2/neu-positive tumors showed only 40% disease-free survival (DFS) at 5 years, compared with over 80% in patients with HER-2/neu-negative tumors (P less than .0001). A similar inverse correlation was observed between overexpression and overall survival in the same group of patients (P = .0001). In a separate analysis involving patients receiving adjuvant chemotherapy, those with HER-2/neu-negative tumors showed significantly improved DFS in response to therapy compared with patients with HER-2/neu-positive tumors. CONCLUSION: Overexpression of HER-2/neu is associated with poor clinical outcome in a subset of node-negative patients with small, ER-positive, predominantly invasive tumors and may play a role in resistance to adjuvant chemotherapy.

Breast Neoplasms↗
PubMed1992

Identification of estrogenic tamoxifen metabolite(s) in tamoxifen-resistant human breast tumors.

PURPOSE: We have shown previously that acquired tamoxifen resistance in an in vivo experimental model is associated with reduced tamoxifen accumulation, isomerization of trans-4-hydroxytamoxifen, and tamoxifen-stimulated tumor growth. The purpose of this study is to isolate and verify the presence of estrogenic tamoxifen metabolites in human breast tumors using high-performance liquid chromatography (HPLC) and mass-spectrometry (MS) techniques. PATIENTS AND METHODS: In the present study, we used HPLC and MS to identify the presence of estrogenic metabolites in tumor samples excised from athymic nude mice and in human breast tumors isolated from patients receiving adjuvant tamoxifen therapy. RESULTS: We identified the presence of metabolite E, a known estrogenic metabolite of tamoxifen, in tamoxifen-resistant MCF-7 human breast tumors implanted in athymic nude mice, as well as in tumors from patients with clinical resistance. Additionally, we separated another estrogenic metabolite, bisphenol, by HPLC, and this was also tentatively confirmed by MS analysis. CONCLUSION: These data suggest that cellular tamoxifen metabolism to estrogenic metabolites may in part contribute to stimulating the growth of hormone-responsive breast tumors following prolonged exposure to tamoxifen. Further evaluation of the relationship between cellular metabolism and acquired tamoxifen resistance is warranted.

Animals↗
PubMed1992

Prognostic potential of DNA flow cytometry measurements in node-negative breast cancer patients: preliminary analysis of an intergroup study (INT 0076).

An ancillary study (INT 0076) to the Intergroup clinical trial of node-negative breast cancer patients (INT 0011) was performed to retrospectively evaluate DNA flow cytometry measurements of ploidy (DNA content) and proliferative capacity (S-phase fraction) for their ability to predict time to recurrence. Of the 915 patients eligible for the clinical trial, 788 were registered for the ancillary flow cytometry study (INT 0076). Four hundred and three of these patients [estrogen receptor (ER)-positive, tumor size less than 3 cm] had been registered to the observation arm of the clinical trial and 385 (ER-negative and/or tumor size greater than or equal to 3 cm) had been randomly assigned to adjuvant chemotherapy (cyclophosphamide, methotrexate, fluorouracil, and prednisone for six cycles) or to observation. Paraffin blocks from 95% (748 of 788) of these patients were obtained, 712 of which had sufficient cancer tissue to be evaluable for the flow cytometric assay. DNA ploidy status (DNA diploid vs DNA aneuploid) was evaluable for 565 (79%) specimens, 64% of which were aneuploid. Proliferative capacity was estimated by the percentage of cells having an S-phase DNA content, using a trapezoidal modeling algorithm(s) as previously described. The median S-phase value for the entire group (both registered and randomly assigned patients) was 6.97%, which defined the cutoff for interpretation of high or low S-phase values. With a median follow-up time of 4.55 years, S-phase fraction, but not ploidy status, is a significant predictor for time to recurrence in both the randomly assigned and the untreated population (observed registered group and observed randomly assigned group).(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗
PubMed1992

Chemotherapy versus observation in high-risk node-negative breast cancer patients.

Postoperative women with breast cancer but without histopathological evidence of metastases to the axillary lymph nodes or clinical evidence of metastases were studied. Six hundred fifty-five "good-risk" patients who were estrogen receptor positive (ER+) with primary tumors less than 3 cm were registered for observation. Twenty-four of these patients were treated with chemotherapy. Five hundred thirty-six "poor-risk" patients who were either ER+ with primary tumors greater than or equal to 3 cm or estrogen receptor negative (ER-) with any primary tumor size were randomly assigned between chemotherapy and observation. Randomization was stratified by type of surgical procedure, number of lymph nodes examined, menopausal status, tumor size, and ER status. The chemotherapy (CMFP) consisted of six 4-week cycles of cyclophosphamide, 100 mg/m2 orally days 1-14; methotrexate, 40 mg/m2 intravenously (IV) days 1 and 8; fluorouracil, 600 mg/m2 IV days 1 and 8; and prednisone, 40 mg/m2 orally days 1-14. Treatment arms in the randomly assigned patients were balanced with respect to pretreatment characteristics. This analysis includes 445 eligible patients entered in the registration arm and 425 eligible patients entered into the randomized treatments. The median follow-up is 4.5 years in the randomly assigned cohort and 4.8 years in the registered cohort. The overall 5-year disease-free survival (DFS) among the randomly assigned patients was 83% with CMFP and 61% with observation (P less than .0001). A DFS treatment benefit was observed in premenopausal and postmenopausal patients as well as in patients with ER+ or ER- tumors. There were fewer local-regional and distant relapses among the CMFP-treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Acquired tamoxifen resistance: correlation with reduced breast tumor levels of tamoxifen and isomerization of trans-4-hydroxytamoxifen.

Acquired tamoxifen resistance represents a major cause of treatment failure in breast cancer. We implanted estrogen receptor-positive MCF-7 human breast cancer cells in athymic nude BALB/c mice as a model to study in vivo acquired tamoxifen resistance. After 4-6 months of tumor growth suppression by trans-tamoxifen, tumor progression was observed despite continued tamoxifen administration. Acquired resistance was not due to loss of estrogen receptors, to alterations in serum or tumor estrogen levels, or to changes in tamoxifen or its major metabolites in serum. Tamoxifen-resistant tumors remained estrogen dependent in vivo. However, resistance was also associated with the ability of tamoxifen to stimulate tumor growth. Resistant tumors were characterized by markedly lower intracellular tamoxifen levels and by isomerization of the potent antiestrogenic metabolite trans-4-hydroxy-tamoxifen to the less potent cis isomer. Metabolic tolerance, as manifested by alterations in cellular concentrations of tamoxifen and its metabolites, may thus be one mechanism for acquired tamoxifen resistance in breast cancer.

Animals↗
PubMed1991

A Southwest Oncology Group phase II Trial of recombinant tumor necrosis factor in metastatic breast cancer.

New approaches are needed in the treatment of advanced breast cancer. In vitro studies have shown that recombinant tumor necrosis factor (TNF) is a growth inhibitor for the MCF-7, ZR-75-1, and BT-20 human breast cancer cell lines. Based on these considerations, the Southwest Oncology Group performed a Phase II trial of recombinant TNF (Genentech) (150 micrograms/m2) given by 30-minute intravenous infusion on days 1 to 5 of every other week for 8 weeks. Patients with metastatic breast cancer who had received one prior chemotherapy regimen for advanced disease were eligible. Of the 22 patients who were entered, 3 were ineligible. Nineteen patients who had a performance status of 2 or less could be examined (median age, 53 years). One possible fatal toxic reaction has been seen in a patient who had intracranial bleeding caused by a previously undiagnosed brain metastasis; no other treatment-related deaths have occurred. Toxicity has included nausea, vomiting, fever, chills, myalgia, and fatigue. No Grade 4 toxicity has been observed. Grade 3 toxic reactions have included hypotension (two patients), diarrhea (one patient), transient leukopenia (two patients), and reversible elevations of liver function test values (two patients). No objective responses have been observed. Twelve of 19 patients have died (median survival time, 8.5 months). Recombinant TNF is inactive as a single agent in patients with previously treated metastatic breast cancer.

Adult↗
PubMed1991

Randomized trial of doxorubicin, bisantrene, and mitoxantrone in advanced breast cancer: a Southwest Oncology Group study.

Four hundred eleven women with metastatic breast cancer were randomly assigned to receive either 60 mg/m2 doxorubicin (130 patients), 320 mg/m2 bisantrene (146 patients), or 14 mg/m2 mitoxantrone (135 patients). The doses were given intravenously every 3 weeks with a cross-over design to determine their relative efficacy and toxicity. To be eligible, patients must have had one previous chemotherapy regimen, and patients who were estrogen receptor positive must have failed endocrine therapy. There were 365 patients assessable for response and 399 assessable for toxic effects. The median age was 57 years; 18% were premenopausal or perimenopausal. Visceral dominant disease was present in 66% of the patients. Ninety-seven percent of the patients had a disease-free interval from diagnosis to first recurrence of less than 1 year. The response rate was 28% with doxorubicin, 13% with bisantrene, and 14% with mitoxantrone (P = .004). Median time to treatment failure was 133 days with doxorubicin, 66 days with bisantrene, and 68 days with mitoxantrone (logrank P = .06). The median survival was 315 days for doxorubicin, 290 days for bisantrene, and 177 days for mitoxantrone (logrank P = .04), although survival at 2 years was similar for all three agents. There were five responses in the 66 patients crossed over to doxorubicin and one response each for patients crossed over to bisantrene (39 patients) or mitoxantrone (63 patients). Toxicity leading to discontinuance of therapy was more common with doxorubicin, and discontinuance of therapy was due primarily to patient's request or cardiotoxicity. The major dose-limiting toxic effect for all three agents was leukopenia. Nausea and vomiting, mucositis, and alopecia were more severe with doxorubicin. Congestive heart failure developed in nine patients treated with doxorubicin, zero patients treated with bisantrene, and two patients treated with mitoxantrone. A decrease in the left ventricular ejection fraction, as defined by moderate to severe Alexander grade changes, was more common in patients treated with doxorubicin (doxorubicin-treated patients = 20%, bisantrene-treated patients = 5%, and mitoxantrone-treated patients = 10%). This study demonstrates that bisantrene and mitoxantrone have only modest activity in metastatic breast carcinoma. The activity of doxorubicin is greater than that of the other two agents, but at a cost of increased toxicity.

Adenocarcinoma↗