Response to second-line chemotherapy in patients with metastatic breast carcinoma previously responsive to first-line treatment

Secondary analyses of the randomized phase III Stop&Go study: efficacy of second-line intermittent versus continuous chemotherapy in HER2-negative advanced breast cancer

Background: Previously, we showed that reintroduction of the same (first-line) chemotherapy at progression could only partially make up for the loss in efficacy as compared to continuously delivered first-line chemotherapy. Here, we report the probability of starting second-line study chemotherapy in the Stop&Go trial, and the progression-free survival (PFS) and overall survival (OS) of patients who received both the first- and second-line treatment in an intermittent versus continuous schedule.Methods: First-line chemotherapy comprised paclitaxel plus bevacizumab, second-line capecitabine or non-pegylated liposomal doxorubicin, given per treatment line as two times four cycles (intermittent) or as eight consecutive cycles (continuous).Results: Of the 420 patients who started first-line treatment within the Stop&Go trial (210:210), a total of 270 patients continued on second-line study treatment (64% of all), which consisted of capecitabine in 201 patients and of non-pegylated liposomal doxorubicin in 69 patients, evenly distributed between the treatment arms. Median PFS was 3.7 versus 5.0 months (HR 1.07; 95% CI: 0.82-1.38) and median OS 10.9 versus 12.4 months (HR 1.27; 95% CI: 0.98-1.66) for intermittent versus continuous second-line chemotherapy. Second-line PFS was positively influenced by prior hormonal therapy for metastatic disease and longer first-line PFS duration, while triple-negative tumor status had a negative influence. Patients with a shorter time to progression (TTP) in first-line (≤10 months) had a higher probability of starting second-line treatment if they received intermittent compared to continuous chemotherapy (OR 1.97; 95% CI: 1.02-3.80).Conclusion: We recommend continuous scheduling of both the first- and second-line chemotherapy for advanced breast cancer.

The role of chemotherapy in treatment of advanced breast cancer: an overview for clinical practice

This review aims to evaluate the role of chemotherapy-containing regimens in the treatment of advanced breast cancer (ABC), with the purpose to optimize selection, sequencing and duration of treatment with the currently available agents for clinical practice. Data from observational as well as randomized phase II and III studies were included. Chemotherapy yielded a median overall survival (OS) of 2 years in registration studies, with comparable efficacy of different agents. Combining chemotherapy agents did not yield OS improvement and caused greater toxicity compared with single-agent chemotherapy. Continuing chemotherapy till progression or unacceptable toxicity generated greater efficacy without detrimental impact on quality of life compared with a limited amount of cycles. In real-world studies, benefits after third-line chemotherapy were modest compared with first- and second-line. Furthermore, effects of previous chemotherapy predicted effects of next-line therapy in real-world. Physicians increasingly prescribed capecitabine or taxanes as first- or second-line chemotherapy over time.

Rechallenging with anthracyclines and taxanes in metastatic breast cancer

Adjuvant use of anthracycline-taxane combination therapy is an accepted strategy in the management of high-risk early-stage breast cancer. However, the introduction of this regimen raises the question of how best to manage those patients who relapse following adjuvant therapy, and whether there is a role for rechallenging in the metastatic setting with the same agent, or class of agent, that has been utilized in the adjuvant setting. This Review examines the evidence for rechallenging with both anthracyclines and taxanes, and highlights the issues that need to be examined in the context of future clinical trials.

Liver resection for breast cancer metastasis: does it improve survival?

PURPOSE

To assess the outcome and prognostic factors of liver surgery for breast cancer metastasis.

METHODS

We retrospectively examined 16 patients who underwent partial liver resection for breast cancer liver metastasis (BCLM). All patients had been treated with chemotherapy or hormonotherapy, or both, before referral for surgery. We confirmed by preoperative radiological examinations that metastasis was confined to the liver. The survival curve was estimated using the Kaplan-Meier method. Univariate and multivariate analysis were conducted to evaluate the role of the known factors of breast cancer survival.

RESULTS

The median age of the patients was 54 years (range 38-68) and the median disease-free interval between the diagnoses of breast cancer and liver metastasis was 54 months (range 7-120). Nine major and 7 minor hepatectomies were performed. There was no postoperative death. The overall 1-, 3-, and 5-year survival rates were 94%, 61%, and 33%, respectively. The median survival rate was 42 months. Univariate analysis revealed that hormone receptor status, number of metastases, a major hepatectomy, and a younger age were associated with a poorer prognosis. The survival rate was not influenced by the disease-free interval, grade or stage of breast cancer, or intraoperative blood transfusions. The number of liver metastases was identified as a significant independent factor of survival according to the Cox proportional hazard model (P = 0.04).

CONCLUSIONS

Liver resection, when done in combination with adjuvant therapy, can improve the prognosis of selected patients with BCLM.

Optimizing the treatment of metastatic breast cancer

There is currently no standard care for metastatic breast cancer; consequently, individual patient and tumor characteristics are among several factors considered in treatment decisions. Clinical studies continue to clarify the roles of endocrine therapy, chemotherapy, and biologic therapy, and results have been promising. For patients with hormone receptor-positive disease, several endocrine agents are currently available including selective estrogen receptor (ER) modulators (tamoxifen and toremifene), aromatase inhibitors (anastrozole, exemestane, and letrozole), as well as the selective ER down-regulator, fulvestrant. Effective first- and second-line, single-agent chemotherapeutic treatments include the taxanes, anthracyclines, vinorelbine, capecitabine, and gemcitabine. The benefits of sequential, single-agent versus combination chemotherapy are also being evaluated. Although combination chemotherapy generally results in a greater objective response, it is associated with similar survival and usually greater toxicity compared with sequential, single-agent chemotherapy. Research involving biologic therapy continues to provide encouraging results for patients with metastatic breast cancer. Chemotherapy plus trastuzumab has been shown to result in greater overall survival versus chemotherapy alone in human epidermal growth factor 2 (HER-2)-positive patients. Trastuzumab has been associated with cardiotoxicity when administered with conventional anthracyclines. Newer formulations of anthracyclines have been developed (e.g., liposomal anthracyclines) to decrease the incidence of cardiotoxicity, and these provide additional treatment options for patients with metastatic breast cancer. The potential effect of all of these endocrine, chemotherapeutic, and biologic treatments on quality of life is an important consideration. Additionally, integrating patient concerns into treatment decisions and collaborating with cross-disciplinary healthcare providers can help to manage the disease more effectively.

Weekly docetaxel/paclitaxel in pretreated metastatic breast cancer

The purpose of our study was to evaluate the feasibility and efficacy of weekly docetaxel/paclitaxel in pretreated advanced breast cancer patients. Twenty-six patients with metastatic breast cancer were included in this study. Three different schedules of treatment were administered. The starting schedule, A1, consisted of docetaxel 60 mg/m2 on day 1 plus paclitaxel 60 mg/m2 over 1 hour, weekly for 18 weeks; this schedule was considered feasible if at least 70% of the planned doses were given on time and without reduction. Schedule A2 consisted of the same doses administered on days 1 and 8 every 3 weeks, and schedule B consisted of docetaxel 25 mg/m2 followed by paclitaxel 40 mg/m2 for 1 hour on days 1 and 8 every 3 weeks for a total of 6 cycles. All patients had received prior anthracyclines, and 19 patients were pretreated with taxanes. Seventy-seven percent of patients had received at least 2 prior lines of chemotherapy. Twenty-five patients are assessable for toxicity and efficacy. A total of 109 cycles of chemotherapy have been administered, with a median of 4 cycles per patient (range, 1-8 cycles). The median delivered dose intensity was 27 mg/m2/week for paclitaxel (range, 18-50 mg/m2/week) and 17 mg/m2/week (range, 12-39 mg/m2/week) for docetaxel. Six patients received schedule A1. This schedule was considered not feasible due to neutropenia grade > 2, mucositis, and diarrhea grade 2, which required dose reduction/omission in 33% of administrations. For this reason, treatment in the following 5 patients was omitted on day 15 (schedule A2). Schedule B was found to be more feasible with 16% of dose reductions/omissions. The overall response rate was 68% (95% CI, 50%-86%) with a median duration of response of 10 months (range, 2-18+ months). Treatment was well tolerated; myelosuppression was rare and grade 3 cutaneous toxicity was observed in only 2 patients. In conclusion, weekly docetaxel/paclitaxel is active at low dosages and was well tolerated as salvage chemotherapy in metastatic breast cancer. This regimen represents a valid option as a salvage treatment in taxane- and anthracycline-pretreated patients.

[Hepatic resection for breast cancer metastases: results and prognosis (65 cases)]

STUDY AIM

To report results of liver resections for breast cancer liver metastasis (BCLM) and to evaluate the rate of survival and the prognostic factors.

PATIENTS AND METHOD

Between 1988 and 1999, 69 patients were operated on for BCLM and 65 who had liver resection were analyzed. The selection criteria for surgery were: normal performance status and liver function test; radiological objective response to chemotherapy (and/or hormonotherapy); in cases of non-isolated BCLM, complete response of associated metastatic site (usually bone) and no brain metastases. The mean age of the 65 patients was 47 (30-70) years. BCLM was diagnosed an average of 60 (0-205) months after the initial cancer. The BCLM was more frequently solitary (n = 44). The mean diameter was 3.8 (0-12) cm. The mean number of cycles of chemotherapy before surgery was 7.5 (3-24). Liver resections included major hepatectomy (n = 31): right n = 19, extended left n = 4, left n = 8, minor hepatectomy (n = 25) and limited resection (n = 9).

RESULTS

There was no postoperative mortality. The 18% morbidity rate included a majority of pleural effusions with two reoperations. The median follow-up was 41 months (6-100 months). The survival rate after surgery was 90% at 1 year, 71% at 3 and 46% at 4 years. Thirteen patients are alive at 4 years. The 36-month survival rate differed according to the time to onset of BCLM: 55% before versus 86% after 48 months (p = 0.01). The other studied factors were not statistically associated with survival. The recurrence rate in the remaining liver at 36 months differed according to the lymph node status of the initial breast cancer: 40% for N0-N1 versus 81% for N1b-N2 (p = 0.01) and according to the type of liver resection: 45% for minor liver resection versus 73% for major (p = 0.02).

CONCLUSION

Adjuvant liver surgery should be included in multicenter treatment protocols for medically-controlled breast cancer liver metastasis.

Selection of candidates for oral etoposide salvage chemotherapy in heavily pretreated breast cancer patients

Metastatic breast cancer (MBC) is still in most cases an uncurable disease and the main goal of treatment is a good quality of life for these patients. Therefore it is very important to select patients who are appropriate candidates for the particular salvage chemotherapy (CT) schedule. The aim of our study was to assess treatment response to oral etoposide, and to analyze its relationship with patients' and disease characteristics. Seventy-five patients with bidimensionally measurable MBC were included into our study. For most of the patients treatment with etoposide was third-line CT regimen and most of them (90%) had been exposed to previous anthracycline-based CT. Etoposide was administered orally at a dose of 100 mg/day for 10 days every 3 weeks. The overall response rate was 37% (95% CI: 27-50%) with a median time to progression (TTP) and survival of 4.5 and 12 months, respectively. Patients with a long disease-free interval, predominant soft tissue and bone metastases, and less than three metastatic sites responded better to oral etoposide; however, a significantly better response was achieved only in those who had responded to previous CT (46 versus 19%, p=0.04), especially to anthracyclines (50 versus 17%, p=0.016). Response to previous anthracycline-based regimen was the only characteristic that significantly influenced TTP (median TTP: 7 versus 2.5 months, p=0.0066) and survival (median survival: 13.8 versus 5 months, p=0.0072). Toxic side effects were generally mild. Salvage CT with oral etoposide is an appropriate treatment for patients who respond to previous CT, particularly to anthracyclines. It combines a favorable toxicity profile with the major advantage of an oral drug administered at home.

Response to chemotherapy is a major parameter-influencing long-term survival of metastatic breast cancer patients

BACKGROUND

In cancer patients, correlation between response to chemotherapy and gain in survival remains debated. We addressed this question in a multivariate analysis evaluating response to chemotherapy as a factor influencing survival of patients with metastatic breast cancer.

PATIENTS AND METHODS

From 1977 to 1992, 1430 patients included in eight consecutive prospective trials of anthracycline-based first-line chemotherapy in metastatic breast cancer, were available for assessment. Median follow-up was 155 months.

RESULTS

Median survival from the date of randomisation was 24 months. Objective response rate was 63.6%. A complete response (CR) was achieved in 17% (249 patients). In a stepwise forward progression analysis objective response was the first independent prognostic factor for survival. Median survival time was 43 months for complete responders (CR), 29 months for partial responders (PR), 18 months for stable disease (SD), 5 months for progressive disease (PD). The probability of survival at 5 and 10 years was 35% and 15% for CR's and decreased to 18% and 6% for PR's. The timing of best response (at 4 or 8 months) was not related to outcome.

CONCLUSIONS

Response to an anthracycline-based chemotherapy is a major independent prognostic factor in metastatic breast cancer. The use of this factor to investigate new drugs seems to be pertinent. The good prognosis of complete responders justifies further evaluation of new treatment strategies for this patient population.

Activity of exemestane in metastatic breast cancer after failure of nonsteroidal aromatase inhibitors: a phase II trial

PURPOSE

To evaluate the antitumor activity and toxicity of a new steroidal aromatase inactivator, exemestane, in postmenopausal women with metastatic breast cancer who had progressive disease (PD) after treatment with a nonsteroidal aromatase inhibitor.

PATIENTS AND METHODS

In this phase II trial, eligible patients were treated with exemestane 25 mg daily (n = 241) followed, at the time PD was determined, by exemestane 100 mg daily (n = 58).

RESULTS

On the basis of the intent-to-treat analysis by independent review, exemestane 25 mg produced objective responses in 6.6% of patients (95% confidence interval [CI], 3.8% to 10.6%) and overall success (complete response + partial response + no change for 24 weeks or longer) in 24.3% (95% CI, 19.0% to 30.2%). The median durations of objective response and overall success were 58.4 weeks (95% CI, 49.7 to 71.1 weeks) and 37.0 weeks (95% CI, 35.0 to 39.4 weeks), respectively. Increasing the dose of exemestane to 100 mg upon the development of PD produced one partial response (1.7%; 95% CI, 0.0% to 9.2%). Both dosages were well tolerated and were discontinued because of adverse events in only 1.7% of patients.

CONCLUSION

Exemestane 25 mg once daily seems to be an attractive alternative to chemotherapy for the treatment of patients with metastatic breast cancer after multiple hormonal therapies have failed.

Hepatic resection in metastatic breast cancer: results and prognostic factors

AIMS

Breast cancer liver metastases (BCLM) usually indicate the presence of disseminated cancer with a very poor prognosis. However, systemic treatments now allow control of tumour progression in certain cases. We evaluated, in a group of highly selected patients with stabilization or complete response to systemic therapy, a particular management protocol for medically controlled BCLM: <<adjuvant>> liver surgery.

METHODS

Fifty-two patients underwent surgery between May 1988 and September 1997. Results of this strategy are reported, together with analysis of prognostic factors for survival and recurrence in the remaining liver (RRL).

RESULTS

The mean number of cycles of chemotherapy, before surgery, was seven (3-24). Resection was considered to be curative in 86% of cases. The median follow-up was 23 months (1-72 months). The survival after surgery, was 86% at 12 months, 79% at 24 months and 49% at 36 months. The 36-month survival rate differed according to the time to onset of BCLM: 45% before versus 82% after 48 months (P=0.023). The RRL rate at 36 months differed according to the lymph node status of the initial breast cancer: 41% for N0-N1 versus 83% for N1b-N2 (P=0.021).

CONCLUSIONS

Adjuvant liver surgery allowed discontinuation of chemotherapy in 46% of cases and, in this highly selected patient group, allowed good quality prolonged survival. It could be included in multicentre treatment protocols for controlled BCLM, one arm with prolonged chemotherapy, one with adjuvant liver surgery.

Cost-utility analysis of chemotherapy using paclitaxel, docetaxel, or vinorelbine for patients with anthracycline-resistant breast cancer

PURPOSE

Paclitaxel, docetaxel, and vinorelbine have been approved for chemotherapy in patients with advanced breast cancer that is resistant to anthracyclines. Selecting which agent to use is difficult because each possesses advantages and disadvantages related to clinical response, toxicity, method of administration, and cost. A cost-utility analysis was therefore performed to create a rank order on the basis of effectiveness, quality of life, and economic considerations.

PATIENTS AND METHODS

Eighty-eight anthracycline-resistant breast cancer patients who had received paclitaxel (n = 34), docetaxel (n = 29), or vinorelbine (n = 25) during the past 2 years were identified. Total resource consumption was collected, which included expenditures for chemotherapy, supportive care, laboratory tests, management of adverse effects, and all related physician fees. Utilities from 25 oncology care providers and 25 breast cancer patients were estimated using the time trade-off technique. The economic estimates from the chart review and clinical data from the literature were then modeled using the principles of decision analysis.

RESULTS

Each of the three drugs led to a similar duration of quality-adjusted progression-free survival (paclitaxel, 37.2 days; docetaxel, 33.6 days; vinorelbine, 38.0 days). Vinorelbine was the least costly strategy, with an overall treatment expenditure of Can $3,259 per patient, compared with Can $6,039 and Can $10,090 for paclitaxel and docetaxel, respectively.

CONCLUSION

Palliative chemotherapy with vinorelbine in anthracycline-resistant metastatic breast cancer patients has economic advantages over the taxanes and provides at least equivalent quality-adjusted progression-free survival. These benefits are largely related to its lower drug acquisition cost and better toxicity profile.

Receptor-mediated and enzyme-dependent targeting of cytotoxic anticancer drugs

This review is a survey of various approaches to targeting cytotoxic anticancer drugs to tumors primarily through biomolecules expressed by cancer cells or associated vasculature and stroma. These include monoclonal antibody immunoconjugates; enzyme prodrug therapies, such as antibody-directed enzyme prodrug therapy, gene-directed enzyme prodrug therapy, and bacterial-directed enzyme prodrug therapy; and metabolism-based therapies that seek to exploit increased tumor expression of, e.g., proteases, low-density lipoprotein receptors, hormones, and adhesion molecules. Following a discussion of factors that positively and negatively affect drug delivery to solid tumors, we concentrate on a mechanistic understanding of selective drug release or generation at the tumor site.