Partial-Breast Irradiation Versus Whole-Breast Irradiation for Early-Stage Breast Cancer: A Cost-Effectiveness Analysis

Abstract

Purpose-Accelerated partial breast irradiation (PBI) is a new treatment paradigm for early-stage breast cancer. Although PBI may lead to higher local recurrence rates, it may be cost-effective because of better tolerability and lower cost. We aimed to determine the incremental costeffectiveness of PBI compared to whole breast radiation therapy (WBRT) for estrogen-receptor positive postmenopausal women treated for early-stage breast cancer.Methods and Materials-We developed a Markov model to describe health states in the 15 years following radiotherapy (RT) for early-stage breast cancer. External beam (EB) and MammoSite (MS) PBI were considered and assumed to be equally effective but carried different costs. Patients received tamoxifen but not chemotherapy. Utilities, recurrence risks, and costs were adapted from the literature; the baseline utility for no disease after RT was set at 0.92. Probabilistic sensitivity analyses were performed to model uncertainty in the PBI hazard ratio (HR), recurrence pattern, and patient utilities. Costs (in 2004 $US) and QALYs were discounted at 3%/year.Results-The incremental cost-effectiveness ratio for WBRT compared to EB-PBI was $630,000/ QALY; WBRT strongly dominated MS-PBI. One-way sensitivity analysis found the results were sensitive to PBI HR, recurrence pattern, baseline recurrence risk, and NED-PBI utility values. Probabilistic sensitivity showed that EB-PBI was the most cost-effective technique over a wide range of assumptions and societal willingness-to-pay values.Conclusions-EB-PBI was the most cost-effective strategy for postmenopausal women with early-stage breast cancer. Unless the quality-of-life after MS-PBI proves to be superior, it is unlikely to be cost-effective.

Cost-minimization analysis: should partial breast irradiation be utilized over whole breast irradiation assuming equivalent clinical outcomes?

“…Sher, et al [13] developed a Markov model to compare the cost-effectiveness between EB-PBI and MS-PBI to WBI for adjuvant treatment of early-stage breast cancer. They determined that EB-PBI was the most cost-effective treatment arm over a wide range of assumptions and societal willingness-to-pay values, with the incremental cost-effectiveness ratio for WBRT compared with EB-PBI being $630,000/quality-adjusted life-year.…”

“…There have been two cost comparison studies published in the United States comparing APBI to WBI, concluding that EB-PBI was the most cost-effective strategy among the PBI modalities [12][13]. To our knowledge, there have been no publications in Canada comparing costs of the two treatments.…”

Accelerated Partial-Breast Irradiation: A State of the Art Strategy.

“…A shorter course of external beam APBI clearly costs less than a protracted course of external beam WBI in terms of the amount billed to the patient, the number of healthcare resources used, and the financial cost to the patient in terms of time away from work and family [86,87,88]. However, since the inception of single-entry brachytherapy catheters, patterns of reimbursement have changed significantly.…”

“…In addition, this treatment technique is significantly more timeintensive to the physician and medical physicist involved in the case, and reimbursement has varied over time, with the amount paid increasing in accordance with the number of lumens treated, a reflection of the greater complexity of the case. A few publications analyzing the cost of APBI compared with WBI have resulted in mixed findings [87,88,89]. In general, these studies have shown that external beam -based APBI is significantly less expensive than standard fractionation WBI over 5 to 6 weeks.…”

Patterns of Care and Disparities in the Treatment of Early Breast Cancer

“…38 Further, others considered this strategy one of the costlier options for patients with candidate low-risk tumors treated in the era of its initial diffusion. 39 Thus, our documenting the pattern by which this novel-but also potentially unproven and costly-treatment has diffused into the care of breast cancer patients across the United …”