Progression-free survival as surrogate end point for overall survival in clinical trials of HER2-targeted agents in HER2-positive metastatic breast cancer.

BACKGROUND: The gold standard end point in randomized clinical trials in metastatic breast cancer (MBC) is overall survival (OS). Although therapeutics have been approved based on progression-free survival (PFS), its use as a primary end point is controversial. We aimed to assess to what extent PFS may be used as a surrogate for OS in randomized trials of anti-HER2 agents in HER2+ MBC. METHODS: Eligible trials accrued HER2+ MBC patients in 1992-2008. A correlation approach was used: at the individual level, to estimate the association between investigator-assessed PFS and OS using a bivariate model and at the trial level, to estimate the association between treatment effects on PFS and OS. Correlation values close to 1.0 would indicate strong surrogacy. RESULTS: We identified 2545 eligible patients in 13 randomized trials testing trastuzumab or lapatinib. We collected individual patient data from 1963 patients and retained 1839 patients from 9 trials for analysis (7 first-line trials). During follow-up, 1072 deaths and 1462 progression or deaths occurred. The median survival time was 22 months [95% confidence interval (CI) 21-23 months] and the median PFS was 5.7 months (95% CI 5.5-6.1 months). At the individual level, the Spearman correlation was equal to ρ = 0.67 (95% CI 0.66-0.67) corresponding to a squared correlation value of 0.45. At the trial level, the squared correlation between treatment effects (log hazard ratios) on PFS and OS was provided by R(2) = 0.51 (95% CI 0.22-0.81). CONCLUSIONS: In trials of HER2-targeted agents in HER2+ MBC, PFS moderately correlates with OS at the individual level and treatment effects on PFS correlate moderately with those on overall mortality, providing only modest support for considering PFS as a surrogate. PFS does not completely substitute for OS in this setting.

Genetic variant predicts bevacizumab-induced hypertension in ECOG-5103 and ECOG-2100.

BACKGROUND: Bevacizumab has broad anti-tumour activity, but substantial risk of hypertension. No reliable markers are available for predicting bevacizumab-induced hypertension. METHODS: A genome-wide association study (GWAS) was performed in the phase III bevacizumab-based adjuvant breast cancer trial, ECOG-5103, to evaluate for an association between genotypes and hypertension. GWAS was conducted in those who had experienced systolic blood pressure (SBP) >160 mm Hg during therapy using binary analysis and a cumulative dose model for the total exposure of bevacizumab. Common toxicity criteria (CTC) grade 3-5 hypertension was also assessed. Candidate SNP validation was performed in the randomised phase III trial, ECOG-2100. RESULTS: When using the phenotype of SBP>160 mm Hg, the most significant association in SV2C (rs6453204) approached and met genome-wide significance in the binary model (P=6.0 × 10(-8); OR=3.3) and in the cumulative dose model (P=4.7 × 10(-8); HR=2.2), respectively. Similar associations with rs6453204 were seen for CTC grade 3-5 hypertension but did not meet genome-wide significance. Validation study from ECOG-2100 demonstrated a statistically significant association between this SNP and grade 3/4 hypertension using the binary model (P-value=0.037; OR=2.4). CONCLUSIONS: A genetic variant in SV2C predicted clinically relevant bevacizumab-induced hypertension in two independent, randomised phase III trials.

Pathologic findings in MRI-guided needle core biopsies of the breast in patients with newly diagnosed breast cancer.

The role of MRI in the management of breast carcinoma is rapidly evolving from its initial use for specific indications only to a more widespread use on all women with newly diagnosed early stage breast cancer. However, there are many concerns that such widespread use is premature since detailed correlation of MRI findings with the underlying histopathology of the breast lesions is still evolving and clear evidence for improvements in management and overall prognosis of breast cancer patients evaluated by breast MRI after their initial cancer diagnosis is lacking. In this paper, we would like to bring attention to a benign lesion that is frequently present on MRI-guided breast biopsies performed on suspicious MRI findings in the affected breast of patients with a new diagnosis of breast carcinoma.

A randomized phase II pilot trial of adjuvant marimastat in patients with early-stage breast cancer.

BACKGROUND: This pilot trial was performed to evaluate the safety, toxicity and pharmacokinetics of chronic therapy with the matrix metalloproteinase inhibitor marimastat in the adjuvant treatment of breast cancer. PATIENTS AND METHODS: Patients with high-risk node negative or node positive breast cancer received marimastat either 5 or 10 mg p.o. b.i.d. for 12 months. Marimastat was given either as a single agent following completion of adjuvant chemotherapy or concurrently with tamoxifen. RESULTS: Sixty-three patients were enrolled from June 1997 to May 1998. All patients have completed 12 months of treatment or have discontinued therapy due to toxicity, relapse or intercurrent illness. Moderate (WHO criteria) arthralgia/arthritis was reported by 34% of patients receiving 5 mg b.i.d. and 45% of patients receiving 10 mg b.i.d.; severe arthralgia/arthritis was reported by 6% and 23% of patients, respectively. Six patients (19%) receiving 5 mg b.i.d. and 11 (35%) receiving 10 mg b.i.d. discontinued marimastat therapy due to toxicity. Trough plasma levels were rarely within the target range for biological activity (40-200 ng/ml) with mean concentration for patients receiving: 5 mg b.i.d. = 7.5; 5 mg b.i.d. plus tamoxifen = 6.9; 10 mg b.i.d. = 11.9; 10 mg b.i.d. plus tamoxifen = 12.8. CONCLUSIONS: A randomized adjuvant trial with marimastat is not warranted as chronic administration cannot maintain plasma levels with the target range.

Self-reported dietary habits, overall dietary quality and symptomatology of breast cancer survivors: a cross-sectional examination.

Little information is available about the relationship between quality of life of women who have survived breast cancer (specifically, symptoms including those of menopause and depression) and the quality of their diet. In this cross-sectional study, 117 women with known primary breast cancer completed a self-administered food frequency questionnaire (FFQ) reflecting usual diet during the past year, a Survey of Feelings and Attitudes using the Center for Epidemiologic Studies Depression scale (CES-D) and a survey that includes menopausal symptoms among others common to women with a history of breast cancer. When women's responses to the FFQ were scored using the Healthy Eating Index (HEI), most often diets were evaluated as those that 'need improvement' with a mean total HEI score of 67.2. With regard to the CES-D scores, study women averaged 9.5, with 19 women being classified as clinically depressed. HEI and CES-D scores were inversely related (p = -0.22, p = 0.02). A negative correlation was also observed between energy-adjusted calcium intakes and CES-D scores (p = -0.19, p = 0.04). Clinical depressed women had not only lower HEI scores and calcium intakes, but also lower grain and variety scores. Comparisons to national data for disease-free women and that available for those with breast cancer suggest that our study women consumed diets low in energy and dietary variety. Diet quality may be an important factor influencing the manifestation of depressive symptoms in breast cancer survivors or conversely, poorer diet quality may be an outcome of depression.

First-line Herceptin monotherapy in metastatic breast cancer.

The pivotal phase II and III Herceptin trials proved the efficacy and safety of second- or third-line single-agent Herceptin and first-line Herceptin in combination with chemotherapy, respectively. In the current trial, 114 patients were randomized to one of two dose groups of first-line Herceptin monotherapy: standard dose of 4 mg/ kg initial dose followed by 2 mg/kg intravenous (i.v.) weekly; or high dose of 8 mg/kg initial dose followed by 4 mg/kg i.v. weekly. The regimen was generally well tolerated. A similar incidence of adverse events was demonstrated in the two dose groups with the possible exception of acute infusion-related events such as fever and chills as well as rash and dyspnea, which appear to be more prevalent in the higher dose group. The overall response rate was 26% and response rates were similar between the two dose groups (24% for the standard Herceptin dose group and 28% for the high Herceptin dose group). Subgroup analysis determined a higher response rate in IHC 3+ patients (35%) and FISH-positive patients (41%). When women with stable disease for > or =6 months were included with responders, the clinical benefit rate in IHC 3+ patients was 47%. Median survival was 24.4 months, which is comparable with the survival rate seen in the pivotal phase III combination trial (25 months). Therefore, single-agent Herceptin is an important new option for the first-line treatment of HER2-positive metastatic breast cancer patients.

First-line, single-agent Herceptin(R) (trastuzumab) in metastatic breast cancer. a preliminary report.

Following confirmation of the appropriate dosage, safety and potential efficacy of Herceptin(R) (trastuzumab) in small-scale phase I and II trials involving patients with refractory disease, a large trial was conducted in 222 patients with breast cancer who had relapsed after one or two chemotherapy regimens for their metastatic disease. The results showed a positive and durable overall response rate (15% according to a response evaluation committee (REC) assessment) using trastuzumab monotherapy (initial dose 4 mg/kg intravenously (i.v.) followed by 2 mg/kg i.v. weekly). In another recently completed phase II trial, 113 patients were randomised to two dose levels (initial dose of 4 mg/kg i.v. dose followed by 2 mg/kg i.v. weekly, or initial dose of 8 mg/kg followed by 4 mg/kg i.v. weekly) of single-agent trastuzumab as first-line therapy for metastatic disease. The preliminary overall response rate was 23% based on investigator assessment, and tolerability was excellent as in previous trials; efficacy was similar in both dose groups, but the side-effects tended to be more frequent in the higher dose group. The preferred dosage is therefore the same as that currently recommended, i.e. an initial dose of 4 mg/kg i.v. followed by 2 mg/kg weekly i.v. until disease progression.

First-line, single-agent Herceptin(trastuzumab) in metastatic breast cancer: a preliminary report.

Following confirmation of the appropriate dosage, safety and potential efficacy of Herceptin(trastuzumab) in small-scale phase I and II trials involving patients with refractory disease, a large trial was conducted in 222 patients with breast cancer who had relapsed after one or two chemotherapy regimens for their metastatic disease. The results showed a positive and durable overall response rate (15% according to a response evaluation committee (REC) assessment) using trastuzumab monotherapy (initial dose 4 mg/kg intravenously (i.v.) followed by 2 mg/kg i.v. weekly). In another recently completed phase II trial, 113 patients were randomised to two dose levels (initial dose of 4 mg/kg i.v. dose followed by 2 mg/kg i.v. weekly, or initial dose of 8 mg/kg followed by 4 mg/kg i.v. weekly) of single-agent trastuzumab as first-line therapy for metastatic disease. The preliminary overall response rate was 23% based on investigator assessment, and tolerability was excellent as in previous trials; efficacy was similar in both dose groups, but the side-effects tended to be more frequent in the higher dose group. The preferred dosage is therefore the same as that currently recommended, i.e. an initial dose of 4 mg/kg i.v. followed by 2 mg/kg weekly i.v. until disease progression.

Multinational study of the efficacy and safety of humanized anti-HER2 monoclonal antibody in women who have HER2-overexpressing metastatic breast cancer that has progressed after chemotherapy for metastatic disease.

PURPOSE: Overexpression of the HER2 protein occurs in 25% to 30% of human breast cancers and leads to a particularly aggressive form of the disease. Efficacy and safety of recombinant humanized anti-HER2 monoclonal antibody as a single agent was evaluated in women with HER2-overexpressing metastatic breast cancer that had progressed after chemotherapy for metastatic disease. PATIENTS AND METHODS: Two hundred twenty-two women, with HER2-overexpressing metastatic breast cancer that had progressed after one or two chemotherapy regimens, were enrolled. Patients received a loading dose of 4 mg/kg intravenously, followed by a 2-mg/kg maintenance dose at weekly intervals. RESULTS: Study patients had advanced metastatic disease and had received extensive prior therapy. A blinded, independent response evaluation committee identified eight complete and 26 partial responses, for an objective response rate of 15% in the intent-to-treat population (95% confidence interval, 11% to 21%). The median duration of response was 9.1 months; the median duration of survival was 13 months. The most common adverse events, which occurred in approximately 40% of patients, were infusion-associated fever and/or chills that usually occurred only during the first infusion, and were of mild to moderate severity. These symptoms were treated successfully with acetaminophen and/or diphenhydramine. The most clinically significant adverse event was cardiac dysfunction, which occurred in 4.7% of patients. Only 1% of patients discontinued the study because of treatment-related adverse events. CONCLUSION: Recombinant humanized anti-HER2 monoclonal antibody, administered as a single agent, produces durable objective responses and is well tolerated by women with HER2-overexpressing metastatic breast cancer that has progressed after chemotherapy for metastatic disease. Side effects that are commonly observed with chemotherapy, such as alopecia, mucositis, and neutropenia, are rarely seen.

Hormone replacement therapy and high S phase in breast cancer.

CONTEXT: Prolonged postmenopausal hormone replacement therapy (HRT) is associated with increased incidence of breast cancer and, paradoxically, reduced breast cancer mortality. The biological rationale for this discrepancy has not been explored. OBJECTIVE: To compare the prognostic characteristics of cancers arising in women who have used HRT with those in women who never have used HRT. DESIGN: Prospective cohort study from December 1989 to November 1996. SETTING: Teaching hospital in a large midwestern metropolitan area. PATIENTS: Cohort of 331 postmenopausal women who presented consecutively with 349 invasive breast cancers. MAIN OUTCOME MEASURES: Estrogen receptor (ER) status (ER positive vs ER negative) and S phase (low vs high) for current HRT users vs never users. RESULTS: The frequency of high S-phase fraction among cancers in women who were using HRT was markedly increased compared with that in women who had never used HRT (adjusted odds ratio [OR], 2.82; 95% confidence interval [CI], 1.04-7.66). However, the greater frequency of high S-phase fraction was limited to women with ER-positive cancers (for HRT users vs never users, OR, 5.25; 95% CI, 1.36-20.28; for ER-negative cancers in HRT users vs never users, OR, 1.08; 95% CI, 0.20-5.86). CONCLUSIONS: Use of HRT appears to stimulate growth of ER-positive but not ER-negative breast cancer as measured by S-phase fraction. The prognostic significance of high S-phase fraction in current HRT users who have ER-positive tumors is unknown.

Reliability and validity of the Functional Assessment of Cancer Therapy-Breast quality-of-life instrument.

PURPOSE: This is the first published report on the validation of the Functional Assessment of Cancer Therapy-Breast (FACT-B), a 44-item self-report instrument designed to measure multidimensional quality of life (QL) in patients with breast cancer. The FACT-B consists of the FACT-General (FACT-G) plus the Breast Cancer Subscale (BCS), which complements the general scale with items specific to QL in breast cancer. The FACT-B was developed with an emphasis on patients' values and brevity and is available in nine languages. METHODS AND RESULTS: Two validation samples were used for this report. The first (n = 47) was tested twice over a 2-month period to assess sensitivity to change. Significant sensitivity to change in performance status rating (PSR) was demonstrated for the FACT-B total score, the Physical Well-Being (PWB) subscale, the Functional Well-Being (FWB) subscale, and the BCS. Sensitivity to change in QL as measured by the Functional Living Index-Cancer (FLIC) was documented in the FACT-B total score, PWB, FWB, and Emotional Well-Being (EWB). Additional validity and reliability data were obtained from a larger sample (n = 295). The alpha coefficient (internal consistency) for the FACT-B total score was high (alpha = .90), with subscale alpha coefficients ranging from .63 to .86. Evidence supported test-retest reliability, as well as convergent, divergent, and known groups validity. CONCLUSION: The FACT-B is appropriate for use in oncology clinical trials, as well as in clinical practice. It demonstrates ease of administration, brevity, reliability, validity, and sensitivity to change.

Ovarian function in premenopausal women treated with adjuvant chemotherapy for breast cancer.

PURPOSE: Adjuvant chemotherapy for breast cancer causes significant changes in ovarian function. More young women survive breast cancer than ever before and they are at risk of the sequelae of early menopause. We attempted to (1) define menopausal status in the setting of adjuvant chemotherapy; (2) define chemotherapy-related amenorrhea (CRA); (3) document rates of permanent amenorrhea, temporary amenorrhea, and oligomenorrhea among different regimens; and (4) analyze variables that influence ovarian function. DESIGN: We reviewed reports of the effects of adjuvant chemotherapy for breast cancer on ovarian function in premenopausal women. We searched Medline and Cancerlit from 1966 to 1995 on the following terms: breast neoplasms; chemotherapy, adjuvant; menstruation disorders; premature menopause, and amenorrhea. Further references were obtained from reports retrieved in the initial search. RESULTS: A uniform definition of menopause and CRA is lacking. The wide range of CRA rates reported in adjuvant chemotherapy trials is a result, at least in part, of this problem. The average CRA rate reported in regimens based on cyclophosphamide, methotrexate, and fluorouracil (CMF) is 68% (95% confidence interval [CI], 66% to 70%), with a range of 20% to 100%. CRA incidence varies with age, cytotoxic agent, and cumulative dose. CONCLUSION: Ovarian damage is the most significant long-term sequela of adjuvant chemotherapy in premenopausal breast cancer survivors. We suggest a common definition of the following important terms: menopausal status, CRA (early and late), temporary CRA, and oligomenorrhea in the setting of adjuvant treatment. With uniform definitions in place, regimens can be more precisely compared with respect to this important complication.

Tandem peripheral blood progenitor cell transplants as initial therapy for metastatic breast cancer.

PURPOSE: To investigate the use of two sequential courses of high-dose chemotherapy and peripheral blood progenitor cell (PBPC) transplant as initial therapy for patients with untreated metastatic breast cancer. The goal of the study was to maximize treatment intensity through the use of two non-cross-resistant regimens, each equal in intensity to that used in single transplants. METHODS: PBPC were collected after a course of granulocyte colony-stimulating factor (G-CSF) only or of cyclophosphamide, etoposide, and G-CSF. The first transplant regimen consisted of thiotepa (600 mg/m2), cyclophosphamide (6000 mg/m2), and carboplatin (800 mg/m2). After recovery from the first transplant, responding patients received a second course of therapy consisting of busulfan (16 mg/kg) and etoposide (60 mg/kg). RESULTS: Forty-four patients were enrolled. Five patients did not proceed to transplantation due to tumor progression during PBPC mobilization. Five patients achieved complete response after the first transplant, and 14 were in complete remission at the end of the therapy. Six patients remain free of disease after a median followup of 22 months (range 12-27+ months). The 2-year event-free survival for complete responders is 25.4% (standard error 14.4%). Engraftment was prompt, with a median of 8 and 13 days, respectively, to reach a neutrophil count of 500/mm3 and a platelet count of 50,000/mm3. As a result of the gastrointestinal toxicity of the first course, the median interval between transplants was 68 days. The toxicities of the second transplant course were principally hepatic and muco-cutaneous. Hepatic veno-occlusive disease occurred in 12 patients and was a contributor to the death of three. CONCLUSIONS: Rapid hematologic recovery achieved with PBPC made possible the administration of two courses of high-dose chemotherapy without compromising the intensity of either transplant regimen. The adverse effects of the second course, however, were substantially higher than predicted. The outcome of patients achieving a complete response is promising. Overall, the antitumor benefit of this approach in patients with previously untreated metastatic disease was not superior to that achieved with single transplants in patients responding to standard-dose chemotherapy.

Dietary and Chemoprevention Strategies for Breast Cancer Prevention.

Breast cancer is the most common cancer among American women. Strategies to eliminate or cure invasive breast cancer (eg, treatment of established disease and early detection) have been joined by a promising new approach, prevention. Epidemiologic studies have yet to demonstrate that dietary modification can reduce the risk of breast cancer, but important trials are ongoing. The chemoprevention program of the National Cancer Institute (NCI) has been underway for a decade. The discovery of biomarkers, or "intermediate endpoints," that can serve as surrogates for the ultimate endpoint, breast cancer, is crucial to the success of this program. The chemoprevention programs of NCI and the Division of Cancer Prevention and Control have identified promising cancer prevention compounds, many of which are being studied in clinical trials.

Should multicentric disease be an absolute contraindication to the use of breast-conserving therapy?

PURPOSE: Multicentric cancer is present in a large proportion of mastectomies performed as treatment of breast cancer; it has been considered a contraindication to breast conservation. METHODS AND MATERIALS: We reviewed the records of our patients with Stage I or II breast cancer treated with breast conserving surgery and radiation therapy over a 13-year period. Twenty-seven patients had two or more nodules of grossly visible cancer separated by histologically normal breast tissue. All patients had grossly negative margins of excision; however, four patients had microscopically positive margins. Nine patients had positive axillary nodes. All patients received radiation therapy to the breast postoperatively, with a median dose of 50.4 Gy in 28 fractions; 11 patients also received a boost dose of 6-20 Gy to the tumor bed. Eleven patients were given adjuvant chemotherapy and one patient was given adjuvant tamoxifen. RESULTS: With a median follow-up of 53 months, only one patient has relapsed in the breast (3.7%); that patient relapsed in multiple distant sites at the same time. Three patients have died of disseminated disease; the actuarial survival and disease-free survival rates at 4 years are 89%. CONCLUSION: Breast conservation may be considered for patients with multicentric breast cancer discovered at the time of histologic examination. For patients with multicentric disease detected prior to surgery, breast conserving therapy may be appropriate as long as: (1) all clinically and radiographically apparent abnormalities are removed, (2) clear margins of resection are achieved, and (3) there is no extensive intraductal component.

Treatment of metastatic breast cancer with a split-course high-dose chemotherapy regimen and autologous bone marrow transplantation.

PURPOSE: We investigated the role of high-dose chemotherapy and autologous bone marrow transplantation (ABMT) as the initial systemic treatment in patients with hormone-unresponsive metastatic breast cancer. We studied a regimen involving a split-course schedule using sequential administration of two pairs of alkylating agents separated by 5 days of rest. The rest period was intended to provide time for recovery from the treatment-immediate adverse effects, thereby allowing further dose escalation. PATIENTS AND METHODS: The treatment consisted of thiotepa 225 to 300 mg/m2/d (days - 11 to -9), cisplatin 50 to 100 mg/m2/d (days - 11 and -3), and cyclophosphamide 60 mg/kg/d (days - 3 and -2). Dose escalation was performed in the initial 15 patients before reaching dose-limiting toxicities. When feasible, responding patients received posttransplant irradiation to sites of residual or prior bulky disease. Patients with bone marrow or CNS involvement, prior pelvic irradiation, or age greater than 55 years were excluded. RESULTS: Thirty-nine patients with measurable or assessable tumor were enrolled: 23 with visceral metastases, 11 with only soft tissue disease, and five with skeletal involvement. Twenty-five patients had received no chemotherapy for metastatic disease before transplantation. The dose-limiting toxicities of this therapy were renal and gastrointestinal. Six patients died from complications: four of a fungal infection and two of hemorrhage. A complete response was achieved in 14 patients (36%), three of whom are free of disease at 79+, 55+, and 40+ months after transplantation. Ten of 25 patients not treated with standard-dose chemotherapy for metastatic disease achieved a complete response (40%). The three patients in continuous remission were in the untreated relapse group. CONCLUSION: This single high-dose treatment achieved a relatively high complete response rate in patients with metastatic breast cancer and may have cured some of them. On the other hand, the split-course dose schedule as tested here did not permit significant dose-intensification.

Sequential transplants using mobilized peripheral blood progenitor cells.

Modest success has been achieved with the use of high-dose cytotoxic therapy and bone marrow transplantation in solid tumors. Patient outcome can potentially be improved with further intensification of the therapy. The rapid hematologic recovery achieved with mobilized peripheral blood progenitor cells (PBPC) may reduce the toxicity of transplantation enabling the use of sequential courses of myeloablative therapy. We report on 42 patients with solid tumors enrolled in a tandem transplant protocol involving the use of PBPC mobilized with cyclophosphamide (4 g/m2), etoposide (1 g/m2), and granulocyte-colony-stimulating factor (G-CSF: 10 micrograms/kg/day). This regimen significantly increased the number of circulating progenitor cells; only 1-2 aphereses were sufficient to collect 2.5 x 10(8)/kg mononuclear cells, our goal for each transplant course. The median number of circulating colony-forming units (CFU) and CD34+ cells obtained for each transplant course were 70.3 x 10(4)/kg, and 11.7 x 10(6)/kg, respectively. There was a significant correlation between the numbers of CD34+ cells and CFU measured in the apheresis product (r = 0.49, P = .003). The first transplant regimen given to 38 patients consisted of thiotepa, carboplatin, and cyclophosphamide. The second transplant regimen given to 29 patients consisted of busulfan and etoposide. Hematologic recovery was comparable after each of the two transplant courses. The median time to neutrophil recovery over 0.5 x 10(9)/L and to platelet transfusion independence was 9 and 8 days, respectively. There was no difference in engraftment rates after transplant with PBPC only (n = 28 courses) compared to transplant with PBPC plus bone marrow (n = 39 courses).(ABSTRACT TRUNCATED AT 250 WORDS)