Background/objectives: There is increasing evidence that a subset of patients with stage IV pancreatic ductal adenocarcinoma (PDAC) and liver-only metastasis may benefit from surgical resection of both the primary tumor and metastatic lesions.
Methods: A meta-analysis and systematic review were conducted in patients with stage IV PDAC and hepatic-only metastasis. A comprehensive literature search (January 2015-June 2023) was performed using PubMed with keywords including "pancreatic cancer", "oligometastatic", and "surgery".
Results: Sixteen articles were included in the final review and characterized based on patient selection factors and prognostic indicators. Seven studies reported hazard ratios (HRs) or Kaplan-Meier curves for survival in synchronous resected cohorts versus chemotherapy/palliation alone, which indicated a statistically significant survival benefit in the resection cohorts (pooled HR: 0.41, 95% CI: 0.31-0.53, p < 0.01). Prognostic indicators for synchronous and metachronous resection included lower pre-operative CA19-9, negative margin status of the primary tumor, moderate-to-well-differentiated tumors (grades I-II), and receiving pre-operative chemotherapy.
Conclusions: Surgical/ablation selection factors are evolving, with priorities on (1) response to induction chemotherapy, (2) ability to achieve R0 resection, and (3) minimally invasive approaches remaining critical to optimal patient selection. Standardized radiologic and tumor marker evaluation and response to neoadjuvant therapy and optimizing performance status are critical to improved outcomes.
Keywords: hepatic metastasis; oligometastatic; pancreatectomy; pancreatic cancer; pancreaticoduodenectomy; patient selection; surgical selection factors; survival.