Larry Norton--president-elect of ASCO. American Society of Clinical Oncology. Interviewed by Ezzie Hutchinson.
Explore the source record for details and available documents.
Cancer Care Facilities↗
Biomedical subjects
L Norton
Publications and source records attributed to L Norton.
Long-term results of three randomized trials (58831, 58832, 58881) in childhood acute lymphoblastic leukemia: a CLCG-EORTC report. Children Leukemia Cooperative Group.
We present here the long-term results of three randomized clinical trials conducted on children with newly diagnosed acute lymphoblastic leukemia (ALL) between 1983 and 1998 by the Children Leukemia Cooperative Group (CLCG) from EORTC. In study 58831/32, the overall event-free survival (EFS) rates (+/- s.e.) at 6 and 10 years were 66% +/- 1.8% and 65% +/- 1.8%, respectively, and the risk of isolated central nervous system (CNS) relapse was 6% +/- 1% and 7% +/- 1%, respectively. In patients with a standard risk of relapse the omission of cyclophosphamide had no adverse effect on disease-free survival rates at 10 years (trial 58831). In medium- and high-risk patients the omission of radiotherapy did not increase the risk of CNS or systemic relapse (trial 58832). In study 58881 (1989-1998) the overall EFS rate at 8 years was 68.4% +/- 1.2% and the risk of isolated CNS relapse was 4.2%+/-0.5%. In this trial which adressed three randomized questions, the following results were obtained: the combination of cytarabine at high doses with methotrexate at high doses during interval therapy did not improve prognosis. The addition of 6-mercaptopurine iv during maintenance increased the risk of late relapse. E. coli asparaginase was more toxic and has a higher efficacy than Erwinia asparaginase. Leukocyte counts >100 x 10(9)/l, specific genetic abnormalities, a poor initial response to steroids or a high level of minimal residual disease at early time points were consistently associated with an adverse prognosis in the 58881 trial.
Antineoplastic Combined Chemotherapy Protocols↗
Detecting gene copy number fluctuations in tumor cells by microarray analysis of genomic representations.
In this work, we explore the use of representations in conjunction with DNA microarray technology to measure gene copy number changes in cancer. We demonstrate that arrays of DNA probes derived from low-complexity representations can be used to detect amplifications, deletions, and polymorphic differences when hybridized to representations of genomic DNA. The method is both reproducible and verifiable, and is applicable even to microscopic amounts of primary tumors. We also present a mathematical model for array performance that is useful for designing and understanding DNA microarray hybridization protocols. The future applications and challenges of this approach are discussed.
Breast Neoplasms↗
Phase I studies of anti-epidermal growth factor receptor chimeric antibody C225 alone and in combination with cisplatin.
PURPOSE: The epidermal growth factor (EGF) receptor is frequently overexpressed in epithelial tumors. C225 is a human-to-murine chimeric monoclonal antibody that binds to the receptor and inhibits growth of cancer cells expressing the receptor. We evaluated the pharmacokinetics and toxicity of C225 in patients with advanced tumors overexpressing EGF receptors. PATIENTS AND METHODS: We treated 52 patients in three successive phase I clinical trials of C225 as a single dose (n = 13), weekly multiple dose (n = 17), and weekly multiple dose with cisplatin (n = 22). C225 dose levels were 5, 20, 50, and 100 mg/m(2). In the study combining C225 with cisplatin, limited to patients with either head and neck or non-small-cell lung cancer, C225 was further escalated to 200 and 400 mg/m(2). Cisplatin was given at a dose of 60 mg/m(2) once every 4 weeks, and treatment was continued for up to 12 weeks if no disease progression occurred. RESULTS: C225 displayed nonlinear pharmacokinetics, with antibody doses in the range of 200 to 400 mg/m(2) being associated with complete saturation of systemic clearance. C225 clearance did not change with repeated administration or with coadministration of cisplatin. Antibodies against C225 were detected in only one patient, and C225-associated toxicity was minimal. Patients experiencing disease stabilization were seen in all studies. In the study combining C225 and cisplatin, nine (69%) of 13 patients treated with antibody doses >/= 50 mg/m(2) completed 12 weeks of therapy, and two partial responses were observed. CONCLUSION: C225 has dose-dependent pharmacokinetics, and doses that achieve saturation of systemic clearance are well tolerated. C225 given in combination with cisplatin has biologic activity at pharmacologically relevant doses.
Adult↗
Vaccination of high-risk breast cancer patients with mucin-1 (MUC1) keyhole limpet hemocyanin conjugate plus QS-21.
Our objective was to determine whether an immune response can be generated against MUC1 peptide and against tumor cell MUC1 after vaccination with MUC1-keyhole limpet hemocyanin (KLH) conjugate plus QS-21 in breast cancer patients. Nine patients with a history of breast cancer but without evidence of disease were treated with MUC1-KLH conjugate plus QS-21, containing 100 microg of MUC1 and 100 microg of QS-21. s.c. vaccinations were administered at weeks 1, 2, 3, 7, and 19. Peripheral blood was drawn at frequent intervals to assess antibody titers. Skin tests were placed at weeks 1, 3, 9, and 21 to determine delayed type hypersensitivity reactions. Common toxicities included a local skin reaction at the site of the vaccine, usually of 4-5 days' duration, and mild flu-like symptoms usually of 1-2 days' duration. High IgM and IgG antibody titers against synthetic MUC1 were detected. IgG antibody titers remain elevated from a minimum of 106-137 weeks after the first vaccination. Binding of IgM antibody to MCF-7 tumor cells was observed in seven patients, although there was minimal binding of IgG antibody. Two patients developed significant antibody titers post-high-dose chemotherapy and stem cell reinfusion. There was no evidence of T cell activation. This MUC1-KLH conjugate plus QS-21 was immunogenic and well tolerated in breast cancer patients. Additional trials are ongoing to determine the optimal MUC1 peptide for use in larger clinical trials. Further investigation of vaccine therapy in high-risk breast cancer is warranted.
Adjuvants, Immunologic↗
Testing gloves used for common nursing tasks.
Nursing tasks often require high levels of dexterity. Gloves should not hinder hand function. Gloves bought for use by nurses need to be tested in ergonomic trials based on nursing tasks.
Anthropometry↗
Breast conservation therapy for invasive breast cancer in Ashkenazi women with BRCA gene founder mutations.
BACKGROUND: Germline mutations in the BRCA1 and BRCA2 genes are associated with an increased risk of breast cancer. Whether women with breast cancer who have inherited mutations in these genes have a different outcome after breast conservation therapy than women with "sporadic" cancer is unresolved. Consequently, we compared the outcomes after breast conservation therapy in Ashkenazi women with or without germline mutations in BRCA1 and/or BRCA2 (hereafter called BRCA). METHODS: We studied 305 women of Ashkenazi Jewish descent undergoing breast-conserving treatment for 329 invasive breast cancers. We reviewed their clinical records, retrieved their archival tissue samples, and tested those samples for the founder mutations BRCA1 185delAG, BRCA1 5382insC, and BRCA2 6174delT. Genetic results were linked to clinical data and outcomes by univariate and multivariate analyses. All Pvalues are two-sided. RESULTS: We detected mutations in BRCA genes in 28 of 305 women. Women with BRCA mutations were more likely to be diagnosed with cancer before the age of 50 years (P<.001) and to have lymph node involvement (P =.04). Ipsilateral breast tumor recurrence was more common in women with BRCA mutations, although this did not reach statistical significance (relative risk [RR] = 1.79; 95% confidence interval [CI] = 0.64-5.03). Women with mutations were more likely to develop contralateral breast cancer (RR = 3.50; 95% CI = 1.78-8.74; P =.001). Distant disease-free survival was shorter in women with mutations (66.2% versus 84.3% at 10 years; P =.05), as was breast cancer-specific survival (71.9% versus 87.2% at 10 years; P =.02). Tumor stage and nodal status, but not mutation status, were predictive of distant disease-free and breast cancer-specific survival in multivariate analysis. CONCLUSIONS: Women with BRCA founder mutations are at increased risk for breast cancer-related events after breast conservation. However, mutation status is not an independent predictor of survival and should not influence decisions regarding adjuvant therapy. The increased contralateral breast cancer risk in women heterozygous for BRCA mutations mandates careful surveillance.
Analysis of Variance↗
The effect of raloxifene on risk of breast cancer in postmenopausal women: results from the MORE randomized trial. Multiple Outcomes of Raloxifene Evaluation.
CONTEXT: Raloxifene hydrochloride is a selective estrogen receptor modulator that has antiestrogenic effects on breast and endometrial tissue and estrogenic effects on bone, lipid metabolism, and blood clotting. OBJECTIVE: To determine whether women taking raloxifene have a lower risk of invasive breast cancer. DESIGN AND SETTING: The Multiple Outcomes of Raloxifene Evaluation (MORE), a multicenter, randomized, double-blind trial, in which women taking raloxifene or placebo were followed up for a median of 40 months (SD, 3 years), from 1994 through 1998, at 180 clinical centers composed of community settings and medical practices in 25 countries, mainly in the United States and Europe. PARTICIPANTS: A total of 7705 postmenopausal women, younger than 81 (mean age, 66.5) years, with osteoporosis, defined by the presence of vertebral fractures or a femoral neck or spine T-score of at least 2.5 SDs below the mean for young healthy women. Almost all participants (96%) were white. Women who had a history of breast cancer or who were taking estrogen were excluded. INTERVENTION: Raloxifene, 60 mg, 2 tablets daily; or raloxifene, 60 mg, 1 tablet daily and 1 placebo tablet; or 2 placebo tablets. MAIN OUTCOME MEASURES: New cases of breast cancer, confirmed by histopathology. Transvaginal ultrasonography was used to assess the endometrial effects of raloxifene in 1781 women. Deep vein thrombosis or pulmonary embolism were determined by chart review. RESULTS: Thirteen cases of breast cancer were confirmed among the 5129 women assigned to raloxifene vs 27 among the 2576 women assigned to placebo (relative risk [RR], 0.24; 95% confidence interval [CI], 0.13-0.44; P<.001). To prevent 1 case of breast cancer, 126 women would need to be treated. Raloxifene decreased the risk of estrogen receptor-positive breast cancer by 90% (RR, 0.10; 95% CI, 0.04-0.24), but not estrogen receptor-negative invasive breast cancer (RR, 0.88; 95% CI, 0.26-3.0). Raloxifene increased the risk of venous thromboembolic disease (RR, 3.1; 95% CI, 1.5-6.2), but did not increase the risk of endometrial cancer (RR, 0.8; 95% CI, 0.2-2.7). CONCLUSION: Among postmenopausal women with osteoporosis, the risk of invasive breast cancer was decreased by 76% during 3 years of treatment with raloxifene.
Aged↗
Phase II trial of topotecan in advanced breast cancer: a Cancer and Leukemia Group B study.
The topoisomerase I inhibitor topotecan had demonstrated good antitumor activity in several murine tumor systems and in human clonogenic assays by 1993. In that year, the Cancer and Leukemia Group B (CALGB) began a phase II trial to determine its activity in patients with breast cancer who had previously received one course of chemotherapy for advanced breast cancer. Between April 1993 and June 1994, 53 patients of performance status 0-2 entered the study, of whom 47 were eligible and 40 were evaluable. Topotecan was given at a dose of 1.5 mg/m2 over 30 minutes daily for 5 days every 21 days. In the absence of progression or withdrawal of consent, therapy was continued indefinitely. The median age was 58 years (range 30-79). There were no complete responses and four partial responses, resulting in an objective response rate of 10% (95% CI: 3-24%). Responses were noted in lymph nodes, liver, and skin. The median duration of response was 5 months. The median survival was 12 months. Life-threatening toxicities were almost exclusively hematologic. However, myelosuppression was not cumulative. It was concluded that topotecan has only modest activity among women with advanced breast cancer who have previously received one course of chemotherapy. Given its modest activity and predominant hematologic toxicity, it does not appear to be a promising drug for either single-agent or combination chemotherapy in the salvage setting of advanced breast cancer.
Adult↗
Dose-response trial of megestrol acetate in advanced breast cancer: cancer and leukemia group B phase III study 8741.
PURPOSE: To investigate whether dose escalation of megestrol acetate (MA) improves response rate and survival in comparison with standard doses of MA. PATIENTS AND METHODS: Three hundred sixty-eight patients with metastatic breast cancer, positive and/or unknown estrogen and progesterone receptors, zero or one prior trial of hormonal therapy, and no prior chemotherapy for metastatic disease were prospectively randomized into three groups. The groups of patients received either MA 160 mg/d (one tablet per day), MA 800 mg/d (five tablets per day), or MA 1,600 mg/d (10 tablets per day). RESULTS: Patient characteristics were well balanced in the three treatment groups. Three hundred sixty-six patients received treatment and were included in the analyses. The response rates were 23%, 27%, and 27% for the 160-mg, 800-mg, and 1,600-mg arms, respectively. Response duration correlated inversely with dose. Median durations of response were 17 months, 14 months, and 8 months for the 160-mg, 800-mg, and 1,600-mg arms, respectively. No significant differences in the treatment arms were noted for time to disease progression or for survival; survival medians were 28 months (low dose), 24 months (mid dose) and 29 months (high dose). The most frequent and troublesome toxicity, weight gain, was dose-related, with approximately 20% of patients on the two higher-dose arms reporting weight gain of more than 20% of their prestudy weight, compared with only 2% in the 160-mg dose arm. CONCLUSION: With a median follow-up of 8 years, these results demonstrate no advantage for dose escalation of MA in the treatment of metastatic breast cancer.
Adult↗
Sequential dose-dense doxorubicin, paclitaxel, and cyclophosphamide for resectable high-risk breast cancer: feasibility and efficacy.
PURPOSE: Dose-dense chemotherapy is predicted to be a superior treatment plan. Therefore, we studied dose-dense doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) as adjuvant therapy. METHODS: Patients with resected breast cancer involving four or more ipsilateral axillary lymph nodes were treated with nine cycles of chemotherapy, using 14-day intertreatment intervals. Doses were as follows: doxorubicin 90 mg/m2 x 3, then paclitaxel 250 mg/m2/24 hours x 3, and then cyclophosphamide 3.0 g/m2 x 3; all doses were given with subcutaneous injections of 5 microg/kg granulocyte colony-stimulating factor on days 3 through 10. Amenorrheic patients with hormone receptor-positive tumors received tamoxifen 20 mg/day for 5 years. Patients treated with breast conservation, those with 10 or more positive nodes, and those with tumors larger than 5 cm received radiotherapy. RESULTS: Between March 1993 and June 1994, we enrolled 42 patients. The median age was 46 years (range, 29 to 63 years), the median number of positive lymph nodes was eight (range, four to 25), and the median tumor size was 3.0 cm (range, 0 to 11.0 cm). The median intertreatment interval was 14 days (range, 13 to 36 days), and the median delivered dose-intensity exceeded 92% of the planned dose-intensity for all three drugs. Hospital admission was required for 29 patients (69%), and 28 patients (67%) required blood product transfusion. No treatment-related deaths or cardiac toxicities occurred. Doxorubicin was dose-reduced in four patients (10%) and paclitaxel was reduced in eight (20%). At a median follow-up from surgery of 48 months (range, 3 to 57 months), nine patients (19%) had relapsed, the actuarial disease-free survival rate was 78% (95% confidence interval, 66% to 92%), and four patients (10%) had died of metastatic disease. CONCLUSION: Dose-dense sequential adjuvant chemotherapy with doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) is feasible and promising. Several ongoing phase III trials are evaluating this approach.
Adult↗
5-year results of dose-intensive sequential adjuvant chemotherapy for women with high-risk node-positive breast cancer: A phase II study.
PURPOSE: We conducted a phase II pilot study of dose-intensive adjuvant chemotherapy with doxorubicin followed sequentially by high-dose cyclophosphamide to determine the safety and feasibility of this dose-dense treatment and to estimate the disease-free and overall survival in breast cancer patients with four or more involved axillary lymph nodes. PATIENTS AND METHODS: Seventy-three patients received adjuvant treatment with four cycles of doxorubicin 75 mg/m(2) as an intravenous bolus every 21 days, followed by three cycles of cyclophosphamide 3,000 mg/m(2) every 14 days with granulocyte colony-stimulating factor support. RESULTS: Seventy-one patients were assessable, and all but two completed all planned chemotherapy. There was no treatment-related mortality. The most common toxicity was neutropenic fever, which occurred in 39% of patients. Median disease-free survival is 66 months (95% confidence interval, 34 to 98 months), and median overall survival has not yet been reached. At 5 years of follow-up, the disease-free survival is 51.7%, and overall survival is 60.0%. There is no long-term treatment-related toxicity, and no cases of acute myelogenous leukemia or myelodysplastic syndrome have been observed. CONCLUSION: Our pilot study of doxorubicin followed by cyclophosphamide demonstrates the safety and feasibility of the sequential dose-dense plan. Long-term follow-up, although noncomparative, is promising. However, this regimen is associated with a higher incidence of toxicity (and also higher costs) than the standard dose and schedule of doxorubicin and cyclophosphamide, and therefore it should not be used as conventional therapy in the absence of demonstrated improvement of outcome. Randomized trials testing the dose-dense approach have been completed but not yet reported. Because the sequential plan can decrease overlapping toxicities, it is an appropriate platform for the addition of newer active agents, such as taxanes or monoclonal antibodies.
Adult↗
Safety and efficacy of using a single agent or a phase II agent before instituting standard combination chemotherapy in previously untreated metastatic breast cancer patients: report of a randomized study--Cancer and Leukemia Group B 8642.
PURPOSE: We undertook a prospective, randomized phase III trial to evaluate the safety and efficacy of using a phase II agent before initiating therapy with standard combination chemotherapy in metastatic breast cancer patients. PATIENTS AND METHODS: A total of 365 women with measurable metastatic breast cancer, previously untreated with chemotherapy for their metastatic disease, were randomized to receive either immediate chemotherapy with cyclophosphamide, doxorubicin, and fluorouracil (CAF) or up to four cycles of one of five sequential cohorts of single-agent drugs: trimetrexate, melphalan, amonafide, carboplatin, or elsamitrucin, followed by CAF. RESULTS: The toxicity of each single agent followed by CAF was comparable to that of CAF alone. The cumulative response rates for the single agent followed by CAF were not statistically different from those of CAF alone (44% v 52%; P = .24). However, in the multivariate analysis, patients with visceral disease had a trend toward lower response rates on the phase II agent plus CAF arm (P = .078). Although survival and response duration also were not statistically significantly different between the two study arms (P = .074 and P = .069, respectively), there was a suggestion of benefit for the CAF-only arm. CONCLUSION: The brief use of a phase II agent, regardless of its efficacy, followed by CAF resulted in response rates, toxicities, durations of response, and survival statistically equivalent to those seen with the use of CAF alone. These findings support the use of a new paradigm for the evaluation of phase II agents in the treatment of patients with metastatic breast cancer.
Adenine↗
Phase I study of escalating doses of edatrexate in combination with paclitaxel in patients with metastatic breast cancer.
Motivated by the observation of preclinical synergy, a Phase I dose escalation study of edatrexate in combination with a 3-h paclitaxel infusion was performed in patients with advanced breast cancer to determine the maximum tolerated dose (MTD) of edatrexate and the toxicities associated with this combination and to report preliminary observations of efficacy with this novel combination. Thirty-six patients were enrolled in this Phase I trial. Thirty-five eligible patients were treated every 21 days in cohorts of at least three patients and were assessable for toxicity. One patient was ineligible due to hyperbilirubinemia. Stepwise dose escalations of edatrexate were administered until grade >3 nonhematological dose-limiting toxicities were reported. The initial dose level of edatrexate was 180 mg/m2; subsequent cohorts were treated with escalating doses of edatrexate (210, 240, 270, 300, 350, and 400 mg/m2). Edatrexate was administered by i.v. infusion over 1 h. Paclitaxel was administered 24 h later at a fixed dose of 175 mg/m2 as a 3-h infusion with standard dexamethasone, diphenhydramine, and cimetidine premedication. The MTD of edatrexate was reached at the 350 mg/m2 level in this study. Grade 3 diarrhea was seen in one patient at the 300 and 400 mg/m2 dose levels, requiring dose reductions. Two patients experienced grade 4 stomatitis at the 400 mg/m2 dose level and also required dose reduction, establishing the MTD as 350 mg/m2. Grade 3 nausea and vomiting were noted in two of three patients at the highest dose level. Of 35 patients, 4 patients reported grade 3 myalgias and 1 patient reported grade 3 neurosensory complaints, which were seen mostly at the 350 and 400 mg/m2 dose levels; however, 1 patient reported grade 3 myalgias at 180 mg/m2. No cumulative neurotoxicity was observed, and no patient experienced an allergic reaction to paclitaxel. In 23 patients with bidimensionally measurable disease, there were four complete (17%) and seven partial responses, with an overall response rate of 48% (95% confidence interval, 27-69%). All of the responses were seen in patients who had not received prior chemotherapy for stage IV disease. The median duration of response was not assessable because many responding patients went on to receive high-dose chemotherapy treatment with stem cell support. The combination of edatrexate and paclitaxel for treatment of metastatic breast cancer is a feasible and safe regimen. The MTD of edatrexate was 350 mg/m2 when combined with a 3-h infusion of paclitaxel (175 mg/m2) given 24 h later. Activity was noted even among patients who had relapsed shortly after receiving methotrexate- and/or doxorubicin-containing adjuvant regimens. Additional studies evaluating the sequences and dosing schema for this combination are warranted to improve the response proportion and define the duration of the response.
Adult↗
Kinetic concepts in the systemic drug therapy of breast cancer.
Optimal management of cancer today requires a thorough and up-to-date understanding of cancer cell kinetics and biochemistry. This report reviews the history and current standards in these fields and how they affect the contemporary approach to breast cancer management. Also outlined are recommended avenues for future research in cytotoxic chemotherapy programs using the principles of cancer cell kinetics as well as the role of newer approaches, including biologic agents such as trastuzumab (Herceptin) and antiangiogenesis agents, in the future therapy of this disease.
Antibodies, Monoclonal↗
Adjuvant breast cancer therapy: current status and future strategies--growth kinetics and the improved drug therapy of breast cancer.
It is well-established that the adjuvant treatment of breast cancer is effective in prolonging both disease-free and overall survival. The pressing questions are how to improve on existing treatment, whether new agents should be incorporated into adjuvant regimens, and, if so, how they should best be utilized. The application of log-kill principles to the sigmoid growth curve characteristic of human cancers suggests that the chances of eradicating tumor will be increased by dose-dense schedules. If the tumor is composed of several cell lines with different sensitivities, the optimum therapy is likely to consist of several drugs given in sequence at a good dose and on a dense schedule. Such sequential chemotherapy, rather than the use of drugs given in combination at longer intervals, should maximize log-kill at the same time as minimizing tumor regrowth. There is now evidence that the actions of chemotherapy may involve Ras, tyrosine kinases (epidermal growth factor receptor, HER2), TC21, or similar molecules. This concept may provide important clues for optimizing the clinical applications of drug therapy and for designing new therapeutic approaches. It might also explain the reason why dose density may be more effective than other schedules of administration. New blood vessel formation is an obligatory step in the establishment of a tumor in its sigmoid growth course and there is evidence that taxanes adversely affect this process. Major practical advances in the curative drug therapy of cancer should follow the demonstration of better ways to maximize cell kill, the development of predictive in vitro methods of selecting active agents, the discovery of techniques to minimize both drug resistance and host-cell toxicity, and the improved understanding of cancer-stromal interactions and their therapeutic perturbation.
Animals↗
Phase II study of weekly intravenous trastuzumab (Herceptin) in patients with HER2/neu-overexpressing metastatic breast cancer.
The HER2/neu proto-oncogene is overexpressed in 25% to 30% of patients with breast cancer. Trastuzumab (Herceptin; Genentech, San Francisco, CA), a recombinant humanized monoclonal antibody with high affinity for the HER2 protein, inhibits the growth of breast cancer cells overexpressing HER2. In this phase II study the efficacy and toxicity of weekly administration of trastuzumab was evaluated in 46 patients with metastatic breast cancer whose tumors overexpressed HER2. A loading dose of 250 mg trastuzumab was administered intravenously, which was followed by 10 weekly doses of 100 mg each. Upon completion of this treatment period, patients with no disease progression could receive a weekly maintenance dose of 100 mg. Patients in this trial had extensive metastatic disease, and most had received prior anticancer therapy. Ninety percent of patients achieved adequate serum levels of trastuzumab. Toxicity was minimal, and no antibodies against trastuzumab could be detected. Objective responses were observed in 5 of the 43 evaluable patients, which included 1 complete remission and 4 partial remissions, for an overall response rate of 11.6%. Responses were seen in mediastinum, lymph nodes, liver, and chest wall lesions. Minor responses (seen in 2 patients) and stable disease (14 patients) lasted for a median of 5.1 months. These results demonstrate that trastuzumab is well tolerated and clinically active in patients with HER2-overexpressing metastatic breast cancers who have received extensive prior therapy. The regression of human cancer through the targeting of putative growth factor receptors such as HER2 warrants further evaluation of trastuzumab in the treatment of breast cancer.
Adult↗
erbB-2, p53, and efficacy of adjuvant therapy in lymph node-positive breast cancer.
BACKGROUND: We have previously reported that high expression of the erbB-2 gene (also known as HER-2/neu and ERBB2) in breast cancer is associated with patient response to dose-intensive treatment with cyclophosphamide, doxorubicin (Adriamycin), and 5-flurouracil (CAF) on the basis of short-term follow-up of 397 patients (set A) with axillary lymph node-positive tumors who were enrolled in Cancer and Leukemia Group B (CALGB) protocol 8541. METHODS: To validate those findings, we conducted immunohistochemical analyses of erbB-2 and p53 protein expression in an additional cohort of 595 patients (set B) from CALGB 8541, as well as a molecular analysis of erbB-2 gene amplification in tumors from all patients (sets A and B). Marker data were compared with clinical, histologic, treatment, and outcome data. RESULTS: Updated analyses of data from set A (median follow-up, 10.4 years) showed an even stronger interaction between erbB-2 expression and CAF dose, by use of either immunohistochemical or molecular data. A similar interaction between erbB-2 expression and CAF dose was observed in all 992 patients, analyzed as a single group. However, for set B alone (median follow-up, 8.2 years), results varied with the method of statistical analysis. By use of a proportional hazards model, the erbB-2 expression-CAF dose interaction was not significant for all patients. However, in the subgroups of patients randomly assigned to the high- or the moderate-dose arms, significance was achieved. When patient data were adjusted for differences by use of a prognostic index (to balance an apparent failure of randomization in the low-dose arm), the erbB-2 expression-CAF dose interaction was significant in all patients from the validation set B as well. An interaction was also observed between p53 immunopositivity and CAF dose. CONCLUSIONS: The hypothesis that patients whose breast tumors exhibit high erbB-2 expression benefit from dose-intensive CAF should be further validated before clinical implementation. Interactions between erbB-2 expression, p53 expression, and CAF dose underscore the complexities of predictive markers where multiple interactions may confound the outcome.
Adult↗