Six-month progression-free survival-related tumor growth rate after upfront chemotherapy as an outcome measure and potential prognostic or stratification variable for patients with unresectable pancreatic adenocarcinoma: an exploratory study cohorts analysis.

Overall survival (OS) has improved in unresectable/metastatic pancreatic adenocarcinoma (mPDAC) patients. However, it is unclear who should be offered further treatment, and how to assess the response in unmeasurable disease. The study aims to evaluate the role of 6-month progression-free survival (PFS) and the corresponding tumor growth rate after first-line chemotherapy (G6m). After identifying 15 randomized trials (19 cohorts, 4,725 patients), 6-month PFS were extracted from curves and expressed as G6m. Median G6m was higher after polychemotherapy and was significantly associated with OS (β = 0.168; p-value <0.001). The number of drugs and female sex correlated with a slower tumor growth rate. Since it was calculated directly from PFS in this study, it is not surprising that G6m exhibits a similar behavior. However, it can be derived by imaging or other markers, therefore representing a variable distinct from PFS, and as such warrants further evaluation in future studies.