The study entitled “Modeling Personalized Adjuvant TreaTment in EaRly stage coloN cancer (PATTERN)” has been published in the European Journal of Health Economics.  This study describes the development of a decision model for the population-level evaluation of strategies to improve the selection of stage II colon cancer patients who benefit from adjuvant chemotherapy.

In stage II colon cancer, surgical resection is the curative treatment option of choice. Adjuvant chemotherapy is recommended for stage II patients with a high risk of recurrence. Prescribing adjuvant chemotherapy after surgical resection remains a matter of debate; there is no consensus which patients benefit from adjuvant chemotherapy. The correct identification of prognostic and predictive parameters is essential to optimize survival without inducing the harms of overtreatment in patients who will not benefit.

Therefore, we developed a Markov cohort model that can be used to evaluate strategies for the allocation of adjuvant chemotherapy in stage II colon cancer patients. Five health states were included in the Personalized Adjuvant TreaTment in EaRly stage coloN cancer (PATTERN) model; diagnosis, 90-day mortality, death other causes, recurrence and colon cancer death. A large dataset from the Netherlands Cancer Registry (n=2,271) was used to parameterize the model. Transition probabilities were estimated using parametric survival models including relevant clinical and pathological covariates. Subsequently, biomarker status was implemented using data from  three external clinical cohorts. Treatment effect was incorporated based on findings of one of our previous publications in which we pooled data of 9 RCTs. In the current publication, the PATTERN model development, data sources used, parameter estimation, and internal and external validation are described in detail.

In future studies, the PATTERN model will be used to estimate population-level long-term health gain and cost-effectiveness of biomarker-based selection strategies. So are you curious about future predictions with the PATTERN model? Keep an eye on the website!