Preoperative endoscopic ultrasound-guided biopsy does not affect survival in patients with upfront resectable pancreatic carcinoma – a nationwide propensity score matched study

Aims Pancreatic adenocarcinoma is a highly aggressive malignancy and currently the fourth leading cause of cancer-associated mortality. Surgery is the sole curative treatment, but the risk of adverse events is significant due to the invasiveness of the procedure. Role of preoperative EUS-guided biopsy in upfront resectable patients has been a matter of debate due to the risk of false-negative biopsies, but also due to the risk of tumor cell seeding along the biopsy tract. Several studies tried to address this question, but the data is highly susceptible to bias in a retrospective population. Aim of this study was to test whether preoperative EUS-guided biopsy affects survival by using high quality data and propensity score matching to minimize overall risk of bias.

Methods We queried the prospectively maintained nationwide Danish Pancreatic Cancer Group database for patients who underwent surgical resection for pancreatic adenocarcinoma. This database contains high quality data provided by all four tertiary centers involved in treatment of pancreatic cancer in Denmark. Furthermore, the database is directly coupled to the Danish Civil Registration System (CPR), offering real time data on mortality and emigration. For the purposes of this retrospective study, patients who underwent neoadjuvant therapy were excluded and the remaining cohort was matched based on age, sex, Charlson comorbidity score (CCS), American Joint Committee on Cancer (AJCC) stage, type of resection including vessel resection, and the tertiary treatment center. Associations between preoperative EUS-guided biopsy and survival were evaluated by examining Kaplan-Meier plots and uni- and multivariate Cox proportional hazards models. Model assumptions were tested using Grambsch-Therneau test and by examining Schoenfeld residuals.

Results 2259 patients were identified and, following exclusion of patients who received neoadjuvant therapy, split into two groups: EUS-guided biopsy group (EUS) and non-biopsy group (nEUS). 434 constituted the matched cohort (EUS: 217; nEUS: 217), and matching statistics showed very low standardized mean differences indicating well matched data. Mean age was 67.3 years (SD 8.65) and 59.7% of the patients were male (n=259). Most patients had an AJCC stage 2 tumor (n=267, 61.5%) and the most common histological type was ductal adenocarcinoma (n=412, 94.9%). Furthermore, proportion of patients receiving adjuvant therapy was identical in the two groups (65% vs 64.5%). Kaplan-Meier method showed similar survival curves and no associations between preoperative EUS-guided biopsy and survival (p=0.576). Cox proportional hazards model showed associations between classical survival predictors such as AJCC stage (p=0.029), CCS (p=0.006), and adjuvant oncological therapy (p<0.001), but not preoperative EUS-guided biopsy (p=0.400).

Conclusions EUS-guided biopsy did not affect survival in upfront resectable patients with pancreatic adenocarcinoma in this nationwide retrospective propensity score study.

Publication History

Article published online:
27 March 2025