Phase III, multicenter, randomized trial of maintenance chemotherapy versus observation in patients with metastatic breast cancer after achieving disease control with six cycles of gemcitabine plus paclitaxel as first-line chemotherapy: KCSG-BR07-02

Chemotherapy and targeted therapy for women with human epidermal growth factor receptor 2-negative (or unknown) advanced breast cancer: American Society of Clinical Oncology Clinical Practice Guideline

PURPOSE

To identify optimal chemo- and targeted therapy for women with human epidermal growth factor 2 (HER2)- negative (or unknown) advanced breast cancer.

METHODS

A systematic review of randomized evidence (including systematic reviews and meta-analyses) from 1993 through to current was completed. Outcomes of interest included survival, progression-free survival, response, quality of life, and adverse effects. Guideline recommendations were evidence based and were agreed on by the Expert Panel via consensus.

RESULTS

Seventy-nine studies met the inclusion criteria, comprising 20 systematic reviews and/or meta-analyses, 30 trials on first-line treatment, and 29 trials on second-line and subsequent treatment. These trials form the evidence base for the guideline recommendations.

RECOMMENDATIONS

Endocrine therapy is preferable to chemotherapy as first-line treatment for patients with estrogen receptor-positive metastatic breast cancer unless improvement is medically necessary (eg, immediately life-threatening disease). Single agent is preferable to combination chemotherapy, and longer planned duration improves outcome but must be balanced against toxicity. There is no single optimal first-line or subsequent line chemotherapy, and choice of treatment will be determined by multiple factors including prior therapy, toxicity, performance status, comorbid conditions, and patient preference. The role of bevacizumab remains controversial. Other targeted therapies have not so far been shown to enhance chemotherapy outcome in HER2-negative breast cancer.

Maintenance capecitabine and bevacizumab versus bevacizumab alone after initial first-line bevacizumab and docetaxel for patients with HER2-negative metastatic breast cancer (IMELDA): a randomised, open-label, phase 3 trial

BACKGROUND

Longer duration of first-line chemotherapy for patients with metastatic breast cancer is associated with prolonged overall survival and improved progression-free survival. We investigated capecitabine added to maintenance bevacizumab after initial treatment with bevacizumab and docetaxel in this setting.

METHODS

We did this open-label randomised phase 3 trial at 54 hospitals in Brazil, China, Egypt, France, Hong Kong, India, Italy, Poland, Spain, and Turkey. We enrolled patients with HER2-negative measurable metastatic breast cancer; each received three to six cycles of first-line bevacizumab (15 mg/kg) and docetaxel (75-100 mg/m(2)) every 3 weeks. Progression-free patients were randomly assigned with an interactive voice-response system by block (size four) randomisation (1:1) to receive either bevacizumab and capecitabine or bevacizumab only (bevacizumab 15 mg/kg on day 1; capecitabine 1000 mg/m(2) twice per day on days 1-14, every 3 weeks) until progression, stratified by oestrogen receptor status (positive vs negative), visceral metastases (present vs absent), response status (stable disease vs response vs non-measurable), and lactate dehydrogenase concentration (≤1·5 vs >1·5 × upper limit of normal). Neither patients nor investigators were masked to allocation. The primary endpoint was progression-free survival (from randomisation) in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT00929240.

FINDINGS

Between July 16, 2009, and March 7, 2011 (when enrolment was prematurely terminated), 284 patients received initial bevacizumab and docetaxel; 185 (65%) were randomly assigned (91 to bevacizumab and capecitabine versus 94 to bevacizumab only). Progression-free survival was significantly longer in the bevacizumab and capecitabine group than in the bevacizumab only group (median 11·9 months [95% CI 9·8-15·4] vs 4·3 months [3·9-6·8]; stratified hazard ratio 0·38 [95% CI 0·27-0·55]; two-sided log-rank p<0·0001), as was overall survival (median 39·0 months [95% CI 32·3-not reached] vs 23·7 months [18·5-31·7]; stratified HR 0·43 [95% CI 0·26-0·69]; two-sided log-rank p=0·0003). Results for time to progression were consistent with those for progression-free survival. 78 (86%) patients in the bevacizumab and capecitabine group and 72 (77%) in the bevacizumab only group had an objective response. Clinical benefit was recorded in 92 (98%) patients in the bevacizumab alone group and 90 (99%) in the bevacizumab and capecitabine group. Mean change from baseline in global health score did not differ significantly between groups. Grade 3 or worse adverse events during the maintenance phase were more common with bevacizumab and capecitabine than with bevacizumab only (45 [49%] of 91 patients vs 25 [27%] of 92 patients). The most common grade 3 or worse events were hand-foot syndrome (28 [31%] in the bevacizumab and capecitabine group vs none in the bevacizumab alone group), hypertension (eight [9%] vs three [3%]), and proteinuria (three [3%] vs four [4%]). Serious adverse events were reported by ten (11%) patients in the bevacizumab and capecitabine group and seven (8%) patients in the bevacizumab only group.

INTERPRETATION

Despite prematurely terminated accrual and the lack of information about post-progression treatment, both progression-free survival and overall survival were significantly improved with bevacizumab and capecitabine compared with bevacizumab alone as maintenance treatment. These results might inform future maintenance trials and current first-line treatment strategies for HER2-negative metastatic breast cancer.

FUNDING

F Hoffmann-La Roche.

Prolonged complete response after treatment withdrawal in HER2-overexpressed, hormone receptor-negative breast cancer with liver metastases: the prospect of disappearance of an incurable disease

BACKGROUND

Metastatic breast cancer has consistently been viewed as a non-curable disease. Specific palliative treatments such as chemotherapy and hormone therapy have resulted in a mean overall survival of approximately 30 months. While cases of prolonged complete response have been reported with hormone or trastuzumab monotherapy, rendering metastatic breast cancer a chronic disease, any treatment withdrawal has ineluctably led to relapse. Prolonged remission without any anti-cancer treatment has never been reported to our knowledge.

CASE PRESENTATION

We report here the unique observation of the spontaneous evolution of two breast cancer patients with synchronous liver metastases who decided to stop trastuzumab after achieving complete response. They were Caucasian women with synchronous liver metastatic breast carcinoma. Both breast cancers reached skin and regional lymph nodes. There were several liver metastases in both patients. They received surgery, radiotherapy and chemotherapy combined with trastuzumab. They decided to stop their treatment, despite guidelines. After a follow-up longer than 20 months, they did not relapse clinically, radiologically, and biologically.

CONCLUSION

This findings question the belief of the unavoidability of recurrence of metastatic breast cancer, specifically in the liver. It opens up the unprecedented possibility of a cure-like state in exceptional and probably special cases.

Maintenance treatment of trastuzumab for patients with advanced breast cancer to achieve long term survival: two case reports and literature review

Molecular subtyping of breast cancer may provide additional prognostic information regarding patient outcome. The epidermal growth factor receptor (HER2) overexpressing breast cancers are designated as HER2-postive (HER2+) breast cancer and carry a particularly unfavorable prognosis. We present two cases of HER2-postive metastatic breast cancer (MBC) who are found to be a challenge to treat, especially due to the occurrence of brain metastasis. Trastuzumab-based therapy improves clinical outcomes, even if the patient has undergone multi-line treatment. These case reports also emphasize the importance of retesting HER2 status because it can be discordance in receptor status between primary and recurrent breast cancer.

Genetic polymorphisms of SLC28A3, SLC29A1 and RRM1 predict clinical outcome in patients with metastatic breast cancer receiving gemcitabine plus paclitaxel chemotherapy

BACKGROUND

Paclitaxel and gemcitabine (PG) combination chemotherapy is effective as a maintenance chemotherapeutic regimen in metastatic breast cancer (MBC) patients because it increases progression-free survival (PFS), which increases overall survival (OS). The primary purpose of our study was to investigate the association between genetic polymorphisms in the genes involved in PG pathways and clinical outcomes in MBC patients treated with PG chemotherapy.

METHODS

A total of 324 MBC patients were enrolled in this prospective multicenter trial of PG as the first-line chemotherapy. Eighty-five of the 324 patients from two institutes were available for analysis of single nucleotide polymorphisms (SNPs). Germline DNA was extracted from peripheral blood mononuclear cells. Thirty-eight SNPs in 15 candidate genes selected from pathways that may influence the metabolism and transport of, or sensitivity, to PG were analysed.

RESULTS

The median PFS and OS of all 324 patients were 8.7 months (95% confidence interval [CI]: 7.5-9.6 months) and 26.9 months (95% CI: 23.6-30.1 months), respectively. An SNP in SLC28A3 (rs7867504, C/T) was associated with OS (CC or CT versus TT: 37 versus 21 months, p = 0.027, hazard ratio [HR] 2.6, 95% CI: 1.1-6.3). SLC29A1 GA haplotype had a significantly shorter OS (p = 0.030, HR 3.391, 95% CI: 1.13-10.19). RRM1 (ribonucleotide reductase large subunit M1) SNP (rs9937), and haplotypes ATAA and ATGA were significantly associated with neurotoxicity.

CONCLUSION

Genetic polymorphisms in SLC28A3, SLC29A1 and RRM1 can influence the clinical outcome of MBC patients treated with PG chemotherapy. Further studies on the functional mechanisms relating to these germline polymorphisms in these genes are warranted.

Prolonged clinical benefit from the maintenance hormone therapy in patients with metastatic breast cancer

OBJECTIVE

We investigated the efficacy of maintenance hormone therapy (MHT), which was given to hormone positive metastatic breast cancer (MBC) patients in non-progression status to the previous chemotherapy.

METHODS

This study retrospectively analyzed 76 MBC patients who had been treated with MHT from 2006 to 2010 at a single institute.

RESULTS

For the 76 patients reviewed, the median progression free survival (PFS) to MHT was 14.4 months (95% CI, 11.6-17.3). Prolonged PFS was associated with less previous palliative chemotherapy, fewer metastatic sites, and the absence of visceral metastasis in univariate analysis. Multivariate analysis showed that only the number of previous palliative chemotherapy (HR 1.73, 95% CI, 1.00-2.98; P = 0.04) remained as a significant variable. MHT was generally well tolerated.

CONCLUSIONS

MHT showed considerable efficacy and tolerability in this study. Further randomized prospective study is warranted.