Predictive factors for efficacy of capecitabine in heavily pretreated patients with metastatic breast cancer

Capecitabine for hormone receptor-positive versus hormone receptor-negative breast cancer

BACKGROUND

Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer.

OBJECTIVES

To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic.

SEARCH METHODS

On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model.

MAIN RESULTS

We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes).

AUTHORS' CONCLUSIONS

In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.

Features of durable response and treatment efficacy for capecitabine monotherapy in advanced breast cancer: real-world evidence from a large single-centre cohort

PURPOSE

In metastatic breast cancer (MBC) population treated with capecitabine monotherapy, we investigated clinical-pathological features as possible biomarkers for the oncological outcome.

METHODS

Retrospective study of consecutive MBC patients treated at University Hospitals Leuven starting capecitabine between 1999 and 2017. The primary endpoint was the durable response (DR), defined as non-progressive disease for > 52 weeks. Other main endpoints were objective response rate (ORR), time to progression (TTP) and overall survival (OS).

RESULTS

We included 506 patients; mean age at primary breast cancer diagnosis was 51.2 years; 18.2% had de novo MBC; 98.8% were pre-treated with taxanes and/or anthracycline. DR was reached in 11.6%. Patients with DR, as compared to those without DR, were more likely oestrogen receptor (ER) positive (91.5% vs. 76.8%, p = 0.010) at first diagnosis, had a lower incidence of lymph node (LN) involvement (35.6% vs. 49.9%, p = 0.039) before starting capecitabine, were more likely to present with metastases limited to ≤ 2 involved sites (54.2% vs. 38.5%, p = 0.020) and time from metastasis to start of capecitabine was longer (mean 3.5 vs. 2.7 years, p = 0.020). ORR was 22%. Median TTP and OS were 28 and 58 weeks, respectively. In multivariate analysis (only performed for TTP), ER positivity (hazard ratio (HR) = 0.529, p < 0.0001), HER2 negativity (HR = 0.582, p = 0.024), absence of LN (HR = 0.751, p = 0.008) and liver involvement (HR = 0.746, p = 0.013), older age at capecitabine start (HR = 0.925, p < 0.0001) and younger age at diagnosis of MBC (HR = 0.935, p = 0.001) were significant features of longer TTP.

CONCLUSION

Our data display relevant clinical-pathological features associated with DR and TTP in patients receiving capecitabine monotherapy for MBC.

Characterization of Durable Responder for Capecitabine Monotherapy in Patients With Anthracycline- and Taxane-Pretreated Metastatic Breast Cancer

BACKGROUND

The purpose of this study was to evaluate predictive factors and the clinical characteristics of durable responders to capecitabine monotherapy in heavily-treated patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

Between December 2000 and May 2012, a total of 236 evaluable patients with MBC who had been treated with second- or greater-line palliative capecitabine monotherapy after a previous treatment regimen with anthracycline and taxane were included. Capecitabine (1250 mg/m(2) twice daily) was administered for 2 weeks followed by a 1-week rest period.

RESULTS

The response rate was 23.3% and median progression-free survival (PFS) was 4.7 months (95% confidence interval, 4.0-5.5). Among 236 patients, 33 patients (14.0%) showed durable response (>12 months) to capecitabine monotherapy. Patients with durable response showed significantly greater incidence of estrogen receptor (ER) positivity (81.8% vs. 59.1%; P = .012), single-organ metastasis (51.5% vs. 32.0%; P = .047), and absence of lymph node metastasis (75.8% vs. 54.2%; P = .023), compared with patients without durable response. In multivariate analysis, ER positivity and single-organ metastasis retained a significant association with better PFS to capecitabine monotherapy (hazard ratio [HR], 0.51; P < .001 and HR, 0.62; P = .004).

CONCLUSION

Our data suggest that ER positivity and single-organ metastasis can be useful predictive markers for better PFS to second- or greater-line palliative capecitabine monotherapy in anthracycline- and taxane-pretreated MBC patients.

Anthracycline rechallenge using pegylated liposomal doxorubicin in patients with metastatic breast cancer: a pooled analysis using individual data from four prospective trials

BACKGROUND

The aim of this study was to determine the activity of anthracycline rechallenge using pegylated liposomal doxorubicin (PLD) in patients with metastatic breast cancer (MBC) previously treated with conventional anthracyclines.

METHODS

Pooled individual data from four prospective trials were used, and the primary end point of the pooled analysis was clinical benefit rate (CBR). The studies comprised 935 patients, of whom 274 had received PLD in the metastatic setting after prior exposure to conventional anthracyclines (rechallenge population).

RESULTS

The majority of patients were heavily pretreated. Previous anthracycline therapy was administered in the adjuvant (14%) or metastatic setting (46%), or both (40%). The overall CBR from rechallenge with PLD was 37.2% (95% CI, 32.4-42.0). In univariate analyses, the CBR was significantly higher in patients with less exposure to prior chemotherapy, in taxane-naive patients, and in patients with a favourable Eastern Cooperative Group performance status of 0 vs 1 vs 2 (53.3 vs 35.5 vs 18.2%; P<0.001). In multivariate analyses, performance status proved to be the only independent predictor of the CBR achieved with PLD rechallenge (P=0.038). There was no statistically significant difference in CBR regarding the setting, cumulative dose of and/or resistance to prior anthracyclines, or time since prior anthracycline administration.

CONCLUSION

Anthracycline rechallenge using PLD is effective in patients with MBC who have a favourable performance status, regardless of setting, resistance, cumulative dose or time since prior conventional anthracycline therapy.

Randomized phase II trial of first-line trastuzumab plus docetaxel and capecitabine compared with trastuzumab plus docetaxel in HER2-positive metastatic breast cancer

PURPOSE To evaluate trastuzumab (H) and docetaxel (T) with or without capecitabine (X) as first-line combination therapy for human epidermal growth factor receptor 2 (HER2) -positive advanced breast cancer. PATIENTS AND METHODS Patients with HER2-positive locally advanced or metastatic breast cancer were randomly assigned to H (8 mg/kg loading; 6 mg/kg every 3 weeks) plus T (75 mg/m(2) in HTX arm, 100 mg/m(2) in HT arm, every 3 weeks) with or without X (950 mg/m(2) twice per day on days 1 to 14 every 3 weeks). The primary end point was overall response rate (ORR). Results In 222 patients, median follow-up was approximately 24 months. ORR was high with both regimens (70.5% with HTX; 72.7% with HT; P = .717); complete response rate was 23.2% with HTX compared with 16.4% with HT. HTX demonstrated significantly longer progression-free survival: median 17.9 months compared with 12.8 months with HT (hazard ratio, 0.72; P = .045), which translates to a gain of around 5 months. Two-year survival probability was 75% with HTX compared with 66% with HT. Febrile neutropenia (27% v 15%) and grade 3/4 neutropenia (77% v 54%) incidences were higher with HT than HTX. Treatment-related grade 3 hand-foot syndrome (17% v < 1%) and grade 3/4 diarrhea (11% v 4%) occurred more commonly with HTX than HT. One case of congestive heart failure occurred in each arm. CONCLUSION HTX is an effective and feasible first-line therapy for HER2-positive locally advanced or metastatic breast cancer, although it should be reserved for patients with good performance status who are not receiving long-term steroids.