Oligometastatic Pancreatic Cancer to the Liver in the Era of Neoadjuvant Chemotherapy: Which Role for Conversion Surgery? A Systematic Review and Meta-Analysis

Abstract

Background: the improved survival rates achieved using new polychemotherapy regimens in patients with metastatic pancreatic cancer (mPDAC) have suggested a potential role for surgery following a favorable response to initial chemotherapy (IC). The purpose of this systematic review is to summarize the available evidence on the role of surgery following IC in mPDAC, focusing on oligometastatic disease to the liver (lmPDAC). Methods: studies reporting on patients with lmPDAC undergoing surgery after IC were included. The main outcome was overall survival (OS). Results: six observational retrospective studies were included in the qualitative analysis. Data were retrieved on 2087 patients. The most common IC regimen in patients undergoing surgery was FOLFIRINOX (N 84, 73%). Only three studies reported survival comparison among patients treated with IC+surgery vs. IC alone. Median OS varied from 23 to 56 months after conversion surgery vs. 11 to 16.4 months after IC alone. Conclusions: despite wide heterogeneity of chemotherapy regimens, different downstaging criteria and potential selection biases, patients with oligometastatic lmPDAC undergoing surgery after IC have significantly higher survival rates compared to patients treated with IC alone. Future trials are needed for definition of univocal criteria of downstaging, oligometastatic definition and indications for surgery.

Development and Validation of a Simple-to-Use Nomogram to Predict Early Death in Metastatic Pancreatic Adenocarcinoma

“…Apart from demographic factors, early death of mPCa was mainly related to clinical factors such as histological staging, distant metastasis, and therapies including surgery, radiotherapy, and chemotherapy. Surgery has an important impact on the improvement of early death in mPCa, whereas some studies have emphasized the beneficial value of surgery in advanced, and especially, in oligometastatic pancreatic cancer ( 30 , 31 ). However, considering the small number of patients that had received surgery in our study, it might be more prudent to set strict indications for surgery in mPCa based on the clinical conditions of the patient.…”

Better survival of patients with oligo- compared with polymetastatic cancers: a systematic review and meta-analysis of 173 studies

“…There is evidence from randomized clinical trials [12][13][14] that ablative therapies improve survival in patients with OM cancer. For example, in some cancers small randomized studies [12][13][14][15][16][17][18][19][20] already provide evidence of survival improvement in patients that received both systemic and local therapies compared to those that received systemic therapies alone. As a matter of fact, resection of colorectal cancer liver metastases nowadays represents an essential curative option and a primary endpoint in multiple clinical trails.…”

“…Also, oligometastatic tumors at presentation can receive local treatments on the primary tumor and on any single oligometastases. In the SABR-COMET randomized study median overall survival (OS) was 28 months (95% CI [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] in the control group versus 41 months (26-not reached) in the stereotactic body radiotherapy to all metastases group (hazard ratio 0.57, 95% CI 0.30-1.10; P = .09). 6 The aim of this systematic review and meta-analysis was to investigate and establish the prognostic survival of OM compared to non-OM solid tumors.…”

Better survival of patients with oligo- compared with polymetastatic cancers: a systematic review and meta-analysis of 173 studies

“…There is also evidence from randomized clinical trials [12][13][14] that ablative therapies improve survival in patients with OM cancer. For example, in some cancers small randomized studies [12][13][14][15][16][17][18][19][20] already provide evidence of survival improvement in patients that received both systemic and local therapies compared to those that received systemic therapies alone. As a matter of fact, resection of colorectal cancer liver metastases nowadays represents an essential curative option and a primary endpoint in multiple clinical trails.…”

“…One of the first published trials proving benefit of an aggressive local treatment of oligometastases was published in Lancet during 2019. In the SABR-COMET randomized study median overall survival (OS) was 28 months (95% CI [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] in the control group versus 41 months (26-not reached) in the stereotactic body radiotherapy to all metastases group (hazard ratio 0.57, 95% CI 0.30-1.10; P = .09). 6 The aim of this systematic review and meta-analysis was to investigate and establish the prognostic survival of OM compared to non-OM solid tumors.…”