Germline Genetic Variants in GATA3 and Breast Cancer Treatment Outcomes in SWOG S8897 Trial and the Pathways Study.

INTRODUCTION: GATA3 is a critical transcription factor in maintaining the differentiated state of luminal mammary epithelial cells. We sought to determine the prognostic and predictive roles of GATA3 genotypes for breast cancer. PATIENTS AND METHODS: Twelve single nucleotide polymorphisms (SNPs) were genotyped in 2 breast cancer cohorts, including the SWOG S8897 trial where patients were treated with adjuvant chemotherapy (CAF [cyclophosphamide, doxorubicin, 5-fluorouracil] vs. CMF [cyclophosphamide, methotrexate, 5-fluorouracil]) or untreated, and the observational Pathways Study. RESULTS: In the S8897 trial, rs3802604 and rs568727 were associated with disease-free survival and overall survival in the treated group, regardless of chemotherapy regimen. The GG genotype of rs3802604 conferred poorer overall survival (adjusted hazard ratio, 2.45; 95% confidence interval, 1.48-4.05) and disease-free survival (adjusted hazard ratio, 1.95; 95% confidence interval, 1.27-2.99) compared with the AA genotype. Similar associations were found for rs568727. In contrast, no association with either SNP was found in the untreated group. Subgroup analyses indicated that these 2 SNPs more strongly influenced outcomes in the patients who also received tamoxifen. However, the associations in the subgroup with tamoxifen treatment were not replicated in the Pathways Study, possibly owing to substantial differences between the 2 patient cohorts, such as chemotherapy regimen and length of follow-up. Results from joint analyses across these 2 cohorts were marginally significant, driven by the results in S8897. Bioinformatic analyses support potential functional disruption of the GATA3 SNPs in breast tissue. CONCLUSIONS: The present study provides some evidence for the predictive value of GATA3 genotypes for breast cancer adjuvant therapies. Future replication studies in appropriate patient populations are warranted.

Vitamin D Levels, Vitamin D Receptor Polymorphisms, and Inflammatory Cytokines in Aromatase Inhibitor-Induced Arthralgias: An Analysis of CCTG MA.27.

BACKGROUND: Approximately half of women taking aromatase inhibitor (AI) therapy develop AI-induced arthralgia (AIA), and many might discontinue AI therapy because of the pain. Using plasma samples from the MA.27 study, we assessed several factors potentially associated with AIA. PATIENTS AND METHODS: MA.27 is a phase III adjuvant trial comparing 2 AIs, exemestane versus anastrozole. Within an 893-participant nested case-control AIA genome-wide association study, we nested a 72 AIA case-144 control assessment of vitamin D plasma concentrations, corrected for seasonal and geographic variation. We also examined 9 baseline inflammatory cytokines: interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, interferon (IFN)γ, IL-10, IL-12p70, IL-17, IL-23, and chemokine ligand (CCL)-20. Finally, we analyzed the multivariate effects of baseline factors: vitamin D level, previously identified musculoskeletal single nucleotide polymorphisms, age, body mass index, and vitamin D receptor (VDR) Fok-I variant genotype on AIA development. RESULTS: Changes in vitamin D from baseline to 6 months were not significantly different between cases and controls. Elevated inflammatory cytokine levels were not associated with development of AIA. The multivariate model included no clinical factors associated with AIA. However, women with the VDR Fok-I variant genotype were more likely to have a lower IL-1ß level (P = .0091) and less likely to develop AIA after 6 months of AI compared with those with the wild type VDR (P < .0001). CONCLUSION: In this nested case-control correlative study, vitamin D levels were not significantly associated with development of AIA; however, patients with the Fok-I VDR variant genotype were more likely to have a significant reduction in IL-1ß level, and less likely to develop AIA.

Manganese superoxide dismutase polymorphism, treatment-related toxicity and disease-free survival in SWOG 8897 clinical trial for breast cancer.

To date, the few studies of associations between a functional polymorphism in the oxidative stress-related gene manganese superoxide dismutase (SOD2) and breast cancer survival have been inconsistent. In a homogeneous patient population from a large cooperative group trial Southwest Oncology Group (SWOG) 8897, we evaluated this polymorphism in relation to both treatment-related toxicity and disease-free survival (DFS). Among 458 women who received cyclophosphamide-containing adjuvant chemotherapy, those with variant C alleles, related to higher antioxidant activity, experienced less grade 3-4 neutropenia (OR = 0.52, 95% CI = 0.29-0.92) but had worse DFS (HR = 1.59, 95% CI = 0.99-2.55) than women with TT genotypes. No associations were observed among 874 women who were followed without adjuvant therapy. Our results are consistent with the hypothesis that women with higher SOD2 antioxidant activity may experience less treatment-related toxicity but shorter time to disease recurrence or death after breast cancer adjuvant chemotherapy, supporting the modifying effects of oxidative stress-related enzymes on cancer treatment toxicity and efficacy.

Adjuvant chemotherapy and timing of tamoxifen in postmenopausal patients with endocrine-responsive, node-positive breast cancer: a phase 3, open-label, randomised controlled trial.

BACKGROUND: Tamoxifen is standard adjuvant treatment for postmenopausal women with hormone-receptor-positive breast cancer. We assessed the benefit of adding chemotherapy to adjuvant tamoxifen and whether tamoxifen should be given concurrently or after chemotherapy. METHODS: We undertook a phase 3, parallel, randomised trial (SWOG-8814, INT-0100) in postmenopausal women with hormone-receptor-positive, node-positive breast cancer to test two major objectives: whether the primary outcome, disease-free survival, was longer with cyclophosphamide, doxorubicin, and fluorouracil (CAF) given every 4 weeks for six cycles plus 5 years of daily tamoxifen than with tamoxifen alone; and whether disease-free survival was longer with CAF followed by tamoxifen (CAF-T) than with CAF plus concurrent tamoxifen (CAFT). Overall survival and toxicity were predefined, important secondary outcomes for each objective. Patients in this open-label trial were randomly assigned by a computer algorithm in a 2:3:3 ratio (tamoxifen:CAF-T:CAFT) and analysis was by intention to treat of eligible patients. Groups were compared by stratified log-rank tests, followed by Cox regression analyses adjusted for significant prognostic factors. This trial is registered with ClinicalTrials.gov, number NCT00929591. FINDINGS: Of 1558 randomised women, 1477 (95%) were eligible for inclusion in the analysis. After a maximum of 13 years of follow-up (median 8.94 years), 637 women had a disease-free survival event (tamoxifen, 179 events in 361 patients; CAF-T, 216 events in 566 patients; CAFT, 242 events in 550 patients). For the first objective, therapy with the CAF plus tamoxifen groups combined (CAFT or CAF-T) was superior to tamoxifen alone for the primary endpoint of disease-free survival (adjusted Cox regression hazard ratio [HR] 0.76, 95% CI 0.64-0.91; p=0.002) but only marginally for the secondary endpoint of overall survival (HR 0.83, 0.68-1.01; p=0.057). For the second objective, the adjusted HRs favoured CAF-T over CAFT but did not reach significance for disease-free survival (HR 0.84, 0.70-1.01; p=0.061) or overall survival (HR 0.90, 0.73-1.10; p=0.30). Neutropenia, stomatitis, thromboembolism, congestive heart failure, and leukaemia were more frequent in the combined CAF plus tamoxifen groups than in the tamoxifen-alone group. INTERPRETATION: Chemotherapy with CAF plus tamoxifen given sequentially is more effective adjuvant therapy for postmenopausal patients with endocrine-responsive, node-positive breast cancer than is tamoxifen alone. However, it might be possible to identify some subgroups that do not benefit from anthracycline-based chemotherapy despite positive nodes. FUNDING: National Cancer Institute (US National Institutes of Health).

Myeloperoxidase genotypes and enhanced efficacy of chemotherapy for early-stage breast cancer in SWOG-8897.

PURPOSE: Myeloperoxidase (MPO) generates reactive oxygen species and also activates xenobiotics. In a rigorous clinical trial (Southwest Oncology Group SWOG-8897), we examined relationships between genotypes and disease-free survival (DFS) among women treated for breast cancer, as well as those who did not receive adjuvant chemotherapy. PATIENTS AND METHODS: Patients were assigned to risk groups according to standard prognostic features; the low-risk group (n = 753 genotyped) received follow-up only, and the high-risk group (n = 401 genotyped) was randomly assigned to adjuvant cyclophosphamide, methotrexate, and fluorouracil (CMF) or cyclophosphamide, doxorubicin, and fluorouracil (CAF), with or without tamoxifen. DNA from archived normal lymph node tissue was genotyped, and Cox proportional hazard models were used to calculate DFS associated with MPO genotypes. RESULTS: Among women in the treatment arm, those with MPO G alleles had more than a two-fold reduction in hazard of recurrence (adjusted hazard ratio [HR] for GA genotypes, 0.51; 95% CI, 0.21 to 0.99; HR for GG genotypes, 0.41; 95% CI, 0.21 to 0.77). Effects were greatest among women who were further randomly assigned to tamoxifen (HR for GA genotypes, 0.28; 95% CI, 0.12 to 0.69; HR for GG genotypes, 0.19; 95% CI, 0.08 to 0.45). There were no significant associations between genotypes and DFS among women in the untreated arm, and relationships between genotypes and DFS did not differ by CAF or CMF. CONCLUSION: These results, observed in two independent study populations, indicate that high-activity MPO genotypes are associated with better survival among women receiving cyclophosphamide-containing therapy, particularly when followed by tamoxifen therapy. MPO can be inhibited and/or upregulated by commonly used drugs; thus, our findings merit further investigation for optimization of therapeutics for breast cancer.

Nitric oxide synthase variants and disease-free survival among treated and untreated breast cancer patients in a Southwest Oncology Group clinical trial.

PURPOSE: Numerous chemotherapeutic agents are cytotoxic through generation of reactive species, and variability in genes related to oxidative stress may influence disease-free survival (DFS). We examined relationships between DFS and variants in NOS3, as well as NQO1, NQO2, and CBR3, among treated and untreated breast cancer patients in a Southwest Oncology Group clinical trial (S8897). EXPERIMENTAL DESIGN: In the parent trial, women were assigned according to prognostic features; the high-risk group was randomized to cyclophosphamide, i.v. methotrexate, and 5-fluorouracil or to cyclophosphamide, i.v. doxorubicin, and 5-fluorouracil +/- tamoxifen, and the low-risk group did not receive adjuvant therapy. We extracted DNA from normal lymph node tissue and examined functional polymorphisms in NOS3, NQO1, NQO2, and CBR3, in relation to DFS, using Cox proportional hazard model. RESULTS: There were significant interactions between DFS, adjuvant therapy, and NOS3 Glu298Asp and -786 polymorphisms, alone and in combination (P for interaction = 0.008). When NOS3 genotypes were combined, women with genotypes encoding for lower nitric oxide who received chemotherapy had a >2-fold increase in hazard of progression (hazard ratio, 2.32; 95% confidence interval, 1.26-4.25), whereas there was reduced risk for those who did not receive adjuvant therapy (hazard ratio, 0.42; 95% confidence interval, 0.19-0.95). There were no associations between the other genotypes and DFS in either group. CONCLUSION: Variants encoding lower activity of NOS3 may affect outcomes in breast cancer patients, with the direction of risk differing depending on chemotherapy status. These results may mirror the known dual functions of nitric oxide and nitric oxide synthase, depending on oxidative environment.

Chemoendocrine therapy for premenopausal women with axillary lymph node-positive, steroid hormone receptor-positive breast cancer: results from INT 0101 (E5188).

PURPOSE: Chemotherapy, tamoxifen, and ovarian ablation/suppression (OA/OS) are effective adjuvant approaches for premenopausal, steroid hormone receptor-positive breast cancer. The value of combined therapy has not been clearly established. PATIENTS AND METHODS: Premenopausal women with axillary lymph node-positive, steroid hormone receptor-positive breast cancer (1,503 eligible patients) were randomly assigned to six cycles of cyclophosphamide, doxorubicin, and fluorouracil (CAF), CAF followed by 5 years of monthly goserelin (CAF-Z), or CAF followed by 5 years of monthly goserelin and daily tamoxifen (CAF-ZT). The primary end points were time to recurrence (TTR), disease-free survival (DFS), and overall survival (OS) for CAF-Z versus CAF, and CAF-ZT versus CAF-Z. RESULTS: With a median follow-up of 9.6 years, the addition of tamoxifen to CAF-Z improved TTR and DFS but not OS. There was no overall advantage for addition of goserelin to CAF. CONCLUSION: Addition of tamoxifen to CAF-Z improves outcome for premenopausal node-positive, receptor-positive breast cancer. The role of OA/OS alone or with other endocrine agents should be studied more intensely.

Sequencing of tamoxifen and radiotherapy after breast-conserving surgery in early-stage breast cancer.

PURPOSE: Tamoxifen (TAM) is thought to exert a cytostatic effect on hormone-sensitive breast cancer cells. Some preclinical studies show reduced radiosensitivity in irradiated malignant mammary epithelial cells when pretreated with TAM; other studies refute these results. Recent randomized clinical trials suggest an antagonistic effect of TAM on cytotoxic therapy, with improved disease-free survival (DFS) with sequential versus concurrent TAM. An exploratory analysis was undertaken to evaluate the optimal sequencing of TAM and radiotherapy (RT) after breast-conserving surgery. PATIENTS AND METHODS: Southwest Oncology Group trial 8897 (Intergroup 0102) randomly assigned node-negative women with T1-3 breast cancers to cyclophosphamide, doxorubicin, fluorouracil (CAF); CAF --> TAM; cyclophosphamide, methotrexate, fluorouracil (CMF); and CMF --> TAM. For this analysis, data are reported only in the TAM groups. RT was allowed either before adjuvant therapy (sequential [SEQ] RT; 107 patients) or after chemotherapy but concurrent with TAM (concurrent [CONC] RT; 202 patients). Survival data were adjusted for receptor status, age, and tumor size. RESULTS: With a median follow-up of 10.3 years, 10-year DFS values were 83% and 83% for CONC versus SEQ RT groups (log-rank P = .73; P = .76 adjusted for patient characteristics), and 10-year overall survivals were 88% and 90%, respectively (log-rank P = .59; adjusted P = .65). Patterns of failure showed no increase in in-breast recurrence rates between CONC RT and SEQ RT groups, with 10-year local recurrence rates of 7% for CONC RT and 5% for SEQ RT (hazard ratio, 0.73; 95% CI, 0.26 to 2.04; P = .54). CONCLUSION: The current analysis does not suggest an adverse effect on local or systemic control with CONC versus SEQ TAM and RT in node-negative breast cancer. A randomized trial is encouraged to validate these results.

Conventional adjuvant chemotherapy with or without high-dose chemotherapy and autologous stem-cell transplantation in high-risk breast cancer.

BACKGROUND: The prognosis for women with primary breast cancer and 10 or more involved axillary lymph nodes is poor. High-dose chemotherapy with autologous hematopoietic stem-cell transplantation has been reported to be effective in the adjuvant setting for patients at high risk for relapse. METHODS: We randomly assigned 540 female patients with primary breast cancer and at least 10 involved ipsilateral axillary lymph nodes to receive either six cycles of adjuvant chemotherapy with cyclophosphamide, doxorubicin, and fluorouracil (CAF) or the same adjuvant chemotherapy followed by high-dose chemotherapy with cyclophosphamide and thiotepa and autologous hematopoietic stem-cell transplantation. RESULTS: Among the 511 eligible patients, there was no significant difference in disease-free survival, overall survival, or the time to recurrence between those who received CAF alone and those who received CAF plus high-dose chemotherapy and stem-cell transplantation. Among 417 patients fulfilling strict eligibility criteria, the time to recurrence was longer for patients who underwent stem-cell transplantation than for those who received CAF alone. In the transplantation group, nine patients died of transplantation-related complications and a myelodysplastic syndrome or acute myeloid leukemia developed in nine. CONCLUSIONS: The addition of high-dose chemotherapy and autologous hematopoietic stem-cell transplantation to six cycles of adjuvant chemotherapy with CAF may reduce the risk of relapse but does not improve the outcome among patients with primary breast cancer and at least 10 involved axillary lymph nodes. Conventional-dose adjuvant chemotherapy remains the standard of care for such patients.

Adjuvant chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil, vincristine, and prednisone compared with single-agent L-phenylalanine mustard for patients with operable breast carcinoma and positive axillary lymph nodes: 20-year results of a Southwest Oncology Group study.

BACKGROUND: Adjuvant combination chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil plus vincristine and prednisone (CMFVP) was compared with single-agent L-phenylalanine mustard (L-PAM) for the treatment of patients with axillary lymph node positive primary breast carcinoma over 20-years of follow-up. METHODS: Four hundred forty-one women with axillary lymph node positive breast carcinoma were randomized to receive either combination chemotherapy with cyclophosphamide (60 mg/m(2) orally every day for 1 year), fluorouracil (300 mg/m(2) intravenously [IV] weekly for 1 year), methotrexate (15 mg/m(2) IV weekly for 1 year), vincristine (0.625 mg/m(2) IV for 10 weeks), prednisone (30 mg/m(2) orally on Days 1-14, 20 mg/m(2) on Days 15-28, and 10 mg/m(2) on Days 29-42), or single-agent chemotherapy with L-PAM (5 mg/m(2) orally every day for 5 days every 6 weeks for 2 years) after undergoing surgery. Patients were stratified according to menopausal status and number of positive lymph nodes (1-3 positive lymph nodes or > 3 positive lymph nodes). Seventy-seven patients were ineligible. RESULTS: The maximum follow-up is 24 years, with a median follow-up of 21.5 years. Disease free survival and overall survival were superior with CMFVP (two-sided log-rank test; P = 0.0008 and P = 0.007, respectively). For all patients, the estimated 20-year survival rate of patients who received CMFVP was 40% compared with 27% for patients who received L-PAM. There was a substantial survival benefit for CMFVP compared with L-PAM in the subsets of premenopausal patients and patients with four or more positive lymph nodes. The estimated 20-year survival rate for premenopausal women who received CMFVP was 49% compared with 33% for premenopausal women who received L-PAM. Among women with > or = 4 positive lymph nodes, the estimated survival rate for patients who received CMFVP was 31% compared with 15% for patients who received L-PAM. Both regimens were tolerated well. Toxicity was more severe and frequent among patients who received CMFVP. CONCLUSIONS: The authors conclude that, after 20 years of follow-up, adjuvant chemotherapy with CMFVP remains superior to L-PAM for the treatment of patients with lymph node positive breast carcinoma.