Cost-effectiveness in radiation oncology: an uncomfortable but necessary question.

The impact of expensive medical technology on increasinghealthcare costs in the United States rightfully drawsattention from consumers and policymakers alike. Radia-tion oncologyda medical specialty intricately entwinedwith costly technologydhas recently attracted substantialscrutiny for costly treatments with disputed beneﬁt. Thehigh cost of technology inherent to radiation oncologynaturally leads to the question of cost-effectiveness.Cost-effectiveness research incorporates a set of analytictools to weigh or compare the value of a particular inter-vention. In cost-effectiveness research the measure of valuecomes from the ratio of cost divided by the effectiveness ofa given intervention. The functional deﬁnition of effec-tiveness stems from the product of quality of life andsurvival, often measured in quality-adjusted life years(QALY). The incremental cost-effectiveness ratiorepresents the standard endpoint to evaluate the cost-effectiveness of one intervention over another. Incremen-tal cost-effectiveness ratios below a certain dollar perQALY threshold point to a cost-effective treatment. Thestructure of a cost-effectiveness analysis in oncology canvary though typically incorporates tabulating costs fordifferent treatments, as well as integrating probability ofdifferent treatment outcomes (disease control, progression,toxicity), along with the associated quality of life. Theanalytic framework for cost-effectiveness analyses oftenincludes some form of mathematical modeling, such as adecision analytic model or a Markov model. These modelsgo beyond the immediate peritreatment time period, oftenextending over the course of a patient’s life, allowing one tocapture the long-term beneﬁts, detriments, and long-termcosts of individual treatments.In the accompanying article by Hodges et al, the authorsaddress the relevant question of evaluating the cost-effectiveness of intensity modulated radiation therapy(IMRT) compared with 3-dimensional conformal radiationtherapy (3D-CRT) in the management of anal cancer (1).The authors conclude that IMRT does not represent a cost-effective strategy compared with 3D-CRT in anal cancer.Speciﬁcally, they found that IMRT increased the overallcost of treatment by $3847, with a parallel increase of 0.03QALY compared with 3D-CRT. The cost differenceessentially reﬂects the increased cost of IMRToffset by thecost savings from the lower rates of toxicity with IMRT.Likewise, the difference of 0.03 QALY arises from theestimated improvement in quality of life secondary toreduced toxicity with IMRT. Taken together, IMRTwas nota cost-effective treatment option in anal cancer, because theincremental cost-effectiveness ratio of $128,233/QALYwas above the threshold of what the authors consider cost-effective.An important point to consider in cost-effectivenessresearch relates to the idea of a “willingness to pay”threshold, beyond which a treatment would not be consid-ered cost-effective. The idea of a threshold understandablymakes us uncomfortable because it puts a dollar amount ona year of life, though in a society with limited resources itserves as a necessary boundary to identify treatments oflesser value. The commonly used willingness to paybenchmark of $50,000 per QALYarose in the early 1980s,