PURPOSE: Treatment sequences have been incorporated in economic models of several therapeutic areas including autoimmune diseases, cardiology, and neurology, but this has not been a common approach in oncology where comparisons are often specific to line of treatment. Given the number of life-extending, but often high-cost, oncology therapies available, exploring whether to treat in earlier or later line or when to use a specific treatment sequence is of growing interest. There are substantial challenges to sequential modeling in oncology, however, including technical considerations, data requirements and their interpretation, and use in decision-making. This workshop will delineate the role of sequential versus line-specific modelling in oncology, detail the challenges, and propose solutions. DESCRIPTION: Workshop leaders will define alternative approaches to treatment-sequence modeling versus specific treatment-line models and provide an overview of their use in oncology. The merits and challenges of sequential versus line-specific modelling will be covered. We will discuss the questions that each type of model can answer and identify when it is appropriate to undertake sequential modeling. Finally, we will discuss issues related to the interpretation and presentation of these results. Examples will be used throughout the workshop to illustrate the issues. Participants will gain an understanding of both the benefits and challenges of sequential-treatment oncology evaluations. The workshop is directed at health care decision makers and individuals commissioning pharmacoeconomic model evaluations, with the goal of highlighting the advantages and disadvantages of the different approaches.