Retrospective analysis by site of primary tumor of patients with unresectable locally-advanced or metastatic pancreatic adenocarcinoma receiving chemotherapy

The primary tumor site of pancreatic cancer has been suggested as a recommended variable in future studies of treatments of patients with unresectable or metastatic pancreatic adenocarcinoma (mPDAC). The aim of the current study is to analyze the differences between mPDAC of the head and mPDAC of the body-tail, both in prognostic and predictive terms in patients with mPDAC receiving palliative chemotherapy. Data of patients with a diagnosis of mPDAC and receiving chemotherapy (CHT), registered in the database of the division of Medical Oncology of the Ospedale Civile di Sanremo, were analyzed. Thirty-two variables were extracted, and their relationship with primary tumor site and outcome were analyzed. One hundred twenty-nine patients were eligible. The characteristics of patients were different between those with the primary tumor of the pancreatic head or body-tail. After construction of two Cox models, two prognostic factors (the number of CHT lines, the neutrophil reduction after one cycle of CHT) were identified as independent among mPDAC of the head, while only one variables (the number of drugs in the CHT regimen) predicted the outcome of patients with body-tail tumors; after statistical correction for false discovery rate, all the three variables maintained their significant relationship with OS. Despite a similar overall survival among parients with tumors of the head compared to those with tumors of body-tail, a very different disease course was reported, with different prognostic and predictive variables.