Prognosis of adenosquamous carcinoma of the pancreas.

PURPOSE: Pancreatic adenosquamous carcinoma (PASC) is a rare malignant pancreatic tumor, defined as a pancreatic tumor containing at least 30% squamous cell carcinoma component. Most previous publications have reported a poor prognosis for patients with PASC, but data remain scant including clinicopathological features and treatment. This study aimed to characterize the clinicopathological features and to assess the survival of patients with PASC. METHODS: A single center retrospective cohort study at the Lausanne University Hospital (CHUV) was performed. Patients pathologically diagnosed with PASC from January 1, 2010, to December 31, 2023, were included. Overall survival (OS) and disease-free survival (DFS) were calculated using the Kaplan-Meier methods and log-rank test was used for comparisons. RESULTS: A total of 12 patients were histopathologically diagnosed with PASC. Median age at diagnosis was 67.5 years (IQR 59-75.5). Most patients were men (8/12). Eight patients underwent resection and 4 palliative chemotherapy or best supportive care. Six out of 8 patients underwent pancreatoduodenectomy. Median tumor size on pathological analysis was 4.8 cm (IQR 3.4–5.8). Median OS of the entire cohort was 9.2 months (95% CI 2.1–23.4). Median OS from time of diagnosis of patients with and without resection of PASC were 10.2 months (95% CI 2.4–24.1) vs. 8.8 months (95% CI 1.2–11.3, p = 0.23). Median DFS was 2.8 months (95% CI 1.5–23.4) for patients with resection. CONCLUSIONS: Patients with PASC had a very poor prognosis in this cohort. All patients who were not operated died before a year of the diagnosis.