Selecting patients for resection after primary chemotherapy for non-metastatic pancreatic adenocarcinoma

Patients with borderline (BL) or locally advanced (LA) pancreatic adenocarcinoma are usually treated with primary chemotherapy (CT), followed by resection when feasible. Scanty data are available about the criteria to candidate patients to resection after CT.

Between 2002 and 2016 overall 223 patients diagnosed with BL or LA pancreatic adenocarcinoma were primarily treated with Gemcitabine combination (4-drugs or nab-paclitaxel-gemcitabine) for 3-6 months followed by surgery and/or chemoradiation. Resection was carried out when radical resection could be predicted by imaging studies and intraoperative findings. The prognostic value of both pre-treatment factors and treatment response was retrospectively evaluated, searching for criteria that could improve the selection of patients for surgery.

Median survival (MS) for the whole population was 18.3 months. Surgical resection was carried out in 61 patients; MS in resected patients was significantly longer (30.0 months) as compared with 162 non-resected patients (16.5 months) (P < 0.00001). According to response criteria, 48% had a radiological partial response, 47% a stable disease and 5% a disease progression); CA19.9 response (reduction >50%) was obtained in 77.8% of patients. Among resected patients, neither pre-treatment factors, including BL/LA distinction, nor radiological response, were able to prognosticate survival differences. Survival of resected patients having no CA19.9 response was significantly lower as compared with responders (MS 15.0 versus 31.5 months, P = 0.04), and was similar to non-responders patients that did not undergo resection (MS 10.9 months, P= 0.25). Multivariate analysis carried out on the overall population, showed that Karnofsky performance status, T3-T4 status, resection and CA19.9 response were independent prognostic factors, while radiological response, BL/LA distinction and baseline CA19.9 had not significant influence on survival.

CA19.9 response may allow a better selection of patients who will benefit from resection after primary CT for BL or LA pancreatic adenocarcinoma.