A retrospective analysis of early CA19-9 change in salvage chemotherapy for refractory pancreatic cancer

In salvage chemotherapy for refractory pancreatic cancer, early assessment is important to avoid unnecessary toxicities from ineffective chemotherapy. Early CA19-9 change after the first course as a prognostic factor was evaluated in this setting. Patients receiving salvage chemotherapy were retrospectively studied. CA19-9 was measured prior to and after the first course. Cox regression analysis was performed for prognostic factors for progression-free survival (PFS) and overall survival (OS), using the landmark method defined as a day of CA19-9 measurement after the first course. A total of 239 salvage regimens were given in 167 patients. Median PFS and OS were 2.7 and 6.1 months, respectively. Median pretreatment CA19-9 was 2,362 U/mL, and median CA19-9 change after the first course was 17.8 % increase. CA19-9 change was associated with tumor response, and PFS was 1.7 versus 3.5 months and OS was 3.9 and 8.6 months in patients with a parts per thousand yen50 % versus < 50 % increase. In the multivariate analyses, CA19-9 increase a parts per thousand yen50 % was prognostic of both PFS and OS (HR 2.28 and 2.50, p < 0.001, respectively). CA19-9 change after the first course was prognostic of PFS and OS in refractory pancreatic cancer. Early discontinuation should be considered given the palliative setting.