Published Online: December 06, 2012
Marj P. Zimmerman, MS, BSPharm, RPh; and Stanton R. Mehr
Breast cancer was one of the first disorders to profit from the successful application of targeted therapy, and its treatment has changed dramatically from 20 years ago. Despite these advances, breast cancer is responsible for 14% of cancer deaths among women, second only to lung cancer.1
The death rate has decreased since 1990; however, it is projected that about 40,000 will die in 2012 due to the disease (approximately 39,500 women and 400 men),1 with the most deaths occurring among African Americans, followed by Caucasians (Table 1).2 The overall 5-year survival for 2002 to 2008 was 89%, with the longest survival rate in patients having localized disease (98%) and a much lower survival for those with metastasized disease (24%).2
An estimated 227,000 new cases will be diagnosed in 2012, and it is the most frequently diagnosed cancer in women. The incidence of breast cancer had declined by the year 2000 and has since remained stabilized.1 The highest incidence is seen in Caucasians, followed by African Americans.2 Breast cancer remains a cancer that is most often diagnosed in older women; about onefourth of the cases will be diagnosed in women between the ages of 55 and 64 years, followed closely by women between the ages of 65 and 74 years.2
Factors responsible for the reduction in deaths are reduced utilization of hormone replacement therapy for menopausal women, earlier tumor detection, and improved therapies.1
High Incidence Results in Significant Economic Burden
Direct costs in 2010 for breast cancer care were $16.5 billion, which accounted for about 13% of all direct costs attributed to cancer care in the United States.3 In a review of US cost-of-illness studies for breast cancer, the lifetime perpatient costs ranged from $20,000 to $100,000, with higher costs associated with managing patients with advanced disease.4 The Susan G. Komen Foundation estimated an average cost of $22,000 to manage the early stages of breast cancer, whereas stages 3 and 4 of the disease are associated with treatment costs in excess of $120,000.5 A Medicare analysis revealed a mean $110,000 direct lifetime cost of patients with metastatic breastcancer.6 Average direct costs of breast cancer in a managed care population were calculated to be $2896 per member per month (PMPM), with hospitalization accounting for the greatest share, followed by medications and surgical interventions.7
The indirect costs of productivity loss associated with morbidity and premature mortality are much greater: 89% of all breast cancer costs are indrect costs.8 Another study found, using 2007 data, that patients with metastatic breast cancer cost $12.2 billion, or $98,571 per patient per year (including direct medical, palliative/best supportive care, and lost productivity costs).9 Even though there are discrepancies in cost, the societal costs of breast cancer remain high, pointing to the importance of early detection and cost-effective treatment regimens with a goal of curing the disease.
Current Treatment Guided by Genetic Markers
Breast cancers are classified according to hormone receptors and human epidermal growth factor receptor-2 (HER2) status.10 Approximately 70% of breast cancer tumors express a hormone receptor (estrogen or progesterone), and about 20% demonstrate HER2 overexpression.11,12 Recent research has found that there are 4 distinct types of breast cancer, each with its own genetic pattern (Table 2). Of special interest was that triple-negative breast cancer, also known as basal-like breast cancer, was found to have characteristics similar to ovarian cancer, thus offering new therapeutic options to be used to treat this type of cancer.13 Knowing the type of breast cancer the patient presents with guides the clinician in treating the tumor.
Treatment options include radiation, lumpectomy, mastectomy, chemotherapy, or a combination of these options.14 Chemotherapy for breast cancer includes traditional chemotherapy, hormonal therapy, and targeted therapy. Examples of chemotherapy medications are: anthracyclines (doxorubicin, epirubicin), taxanes (paclitaxel, docetaxel), anti-metabolites (capecitabine, gemcitabine), microtubules inhibitors (vinorelbine, eribulin), and others (5-fluorouracil, cyclophosphamide, mitoxantrone, cisplatin, etoposide, vinblastine, ixabepilone, and methotrexate).
Hormonal therapy includes the agents tamoxifen, toremifene, nonsteroidal aromatase inhibitors (anastrozole and letrozole), steroidal aromatase inactivator (exemestane), fulvestrant, megestrol acetate, fluoxymesterone, and ethinyl estradiol.
Targeted therapies for tumors that test positive for HER2 include lapatinib and trastuzumab.14 The breast cancer indication of another targeted therapy, bevacizumab, was revoked by the US Food and Drug Administration (FDA) in November 2011 owing to concerns about its effectiveness and safety.15
Everolimus, an mTOR inhibitor, was approved by the FDA in July 2012 for use in combination with exemestane to treat postmenopausal women with advanced hormone receptor–positive, HER-2 negative breast cancer after failing treatment with letrozole or anastrozole. The FDA had approved the medication for the treatment of other tumors (eg, advanced renal cell carcinoma, advanced neuroendocrine tumors ofpancreatic origin, and renal angiomyolipoma).16 Results from the phase 3 BOLERO-2 study of 724 patients comparing everolimus plus exemastane versus placebo plus exemastane indicated a plus exemastane group compared with 8 months in the combination therapy group (hazard ratio [HR], 0.45; P <.0001). The response rates were 1.7% and 12.6%, respectively. Fewer deaths were reported in the combination therapy group. However, patients older than 64 years did not experience any benefit of the combination treatment.17,18
Pertuzumab, an anti-HER2 therapy, in combination with trastuzumab and docetaxel to treat patients with HER2- positive late-stage breast cancer who have received previous anti-HER2 therapy or chemotherapy. Patients in the triple-therapy group demonstrated a median PFS of 18.5 months versus 12.4 months in the group that did not receive pertuzumab (only trastuzumabwas approved by the FDA in June 2012 and docetaxel) (HR, 0.62; P <.0002).19 Patients receiving the triple therapy had more neutropenia (199 vs 182 patients, respectively), febrile neutropenia (56 vs 30 patients), and diarrhea (32 vs 20 patients) than those receiving trastuzumab and docetaxel.20
In July 2012, GlaxoSmithKline announced that it was not pursuing FDA approval of combined use of trastuzumab and its oncology product lapatinib for women with advanced breast cancer.
Cost-effectiveness and Value Less Clear
A total of $10.2 billion was spent in 2009 on breast cancer medications.21 This is again the result of the high incidence but also the relatively high price of the treatments. Managed care plans should anticipate even higher costs with the FDA approval of everolimus and pertuzumab, as these agents will be added to existing combination drug regimens.
The monthly cost of everolimus, an oral medication, which will be administered daily, will be approximately $7500 per month.22 The clinical trials indicate that the drug will be administered for at least 4 months and potentially longer.18 This total will be added to the cost of exemastane, which has a price tag of several hundred dollars per month.23
Pertuzumab plus trastuzumab will have an even higher cost—pertuzumab will be priced at about $71,000 per year and trastuzumab presently costs $54,000 per year, totaling more than $120,000 per year.24 Both of these medications are specific for HER2-positive breast cancer. The optimal duration of therapy will be at least 6 cycles of therapy.25,26
The duration of treatment can have a major impact on the total cost of therapy. Two different trials for trastuzumab looked at different durations of therapy. The HERA trial compared 1 and 2 years of trastuzumab therapy, with the results indicating that 1 year of therapy is the standard of care.27 Similar results were found in the PHARE study that compared 6 months of trastuzumab therapy with 1 year of therapy.28 The results of these studies demonstrated that 1 year of therapy is the optimal duration of therapy for trastuzumab; however, these studies could have had the potential to either reduce the cost of therapy by 50% or increase it by 100%.
Chemotherapy has contributed to the increased life expectancy of patients with breast cancer; however, a cure remains out of reach.29 Determining the cost-effectiveness of therapies for chronic diseases remains a challenge for clinicians, patients, and society—and early-stage breast cancer is fast coming to be considered a chronic disease.
Cost-utility evaluations of trastuzumab have yielded wide-ranging results, from $29,293 to $127,149 per quality-adjusted life-year (QALY), depending on whether they were receiving monotherapy, trastuzumab plus chemotherapy, or trastuzumab plus endocrine therapy and continuing trastuzumab beyond disease progression. A cost-effectiveness analysis of lapatinib in patients with HER2-positive breast cancer who were receiving lapatinib and capecitabine compared with capecitabine monotherapy alone revealed that the combination therapy was cost-ineffective.30
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