Second-line treatments recommended by the National Cancer Center Network to 
manage advanced-stage gastrointestinal stromal tumours (GIST) were evaluated to 
determine the cost and cost-effectiveness of each intervention in the Mexican 
insurance system, the Instituto Mexicano del Seguro Social (IMSS). Treatments 
examined over a 5-year temporal horizon to estimate long-term costs included 800 
mg day(-1) of imatinib mesylate, 50 mg day(-1) of sunitinib malate (administered 
in a 4 week on/2 week rest schedule), and palliative care. The mean cost (MC), 
cost-effectiveness, and benefit of each intervention were compared to determine 
the best GIST treatment from the institutional perspective of the IMSS. As 
sunitinib was not reimbursed at the time of the study, a Markov model and 
sensitivity analysis were conducted to predict the MC and likelihood of 
reimbursement. Patients taking 800 mg day(-1) of imatinib had the highest MC 
(+/-s.d.) of treatment at $35,225.61 USD (+/-1253.65 USD); while sunitinib 
incurred a median MC of $17,805.87 USD (+/-694.83 USD); and palliative care had 
the least MC over treatment duration as the cost was $2071.86 USD (+/-472.88 
USD). In comparison to palliative care, sunitinib is cost-effective for 38.9% of 
patients; however, sunitinib delivered the greatest survival benefit as 5.64 
progression-free months (PFM) and 1.4 life-years gained (LYG) were obtained in 
the economic model. Conversely, patients on imatinib and palliative care saw a 
lower PFM of 5.28 months and 2.58 months and also fewer LYG (only 1.31 and 1.08 
years, respectively). Therefore, economic modeling predicts that reimbursing 
sunitinib over high dose imatinib in the second-line GIST indication would 
deliver cost savings to the IMSS and greater survival benefits to patients.