Significance of predicted future liver remnant volume on liver failure risk after major hepatectomy: a case matched comparative study

Introduction

Future liver remnant volume (FLRV), a risk factor for liver failure (PHLF) after major hepatectomy (MH), is not routinely measured. This study aimed to evaluate the association between FLRV and PHLF.

Patients and methods

All patients undergoing MH (4 + segments) between 2011 and 2018 were identified from a prospectively maintained single-centre database. Perioperative data were collected for patients with PHLF, who were matched (1:2) with non-PHLF controls. FLRV and FLRV_% (i.e., % of total liver volume) were calculated retrospectively from preoperative CT scans using Synapse-3D software, and compared between the PHLF and matched control groups.

Results

Of 711 patients undergoing MH, PHLF occurred in 27 (3.8%), of whom 24 had preoperative CT scans available. These patients were matched to 48 non-PHLF controls, 98% of whom were classified as being at high risk of PHLF on preoperative risk scoring. FLRV_% was significantly lower in the PHLF group, compared to matched controls (median: 28.7 vs. 35.2%, p = 0.010), with FLRV% < 30% in 58% and 29% of patients, respectively. Assessment of the ability of FLRV_% to differentiate between PHLF and matched controls returned an area under the ROC curve of 0.69, and an optimal cut-off value of FLRV_% < 31.5%, which yielded 79% sensitivity and 67% specificity.

Conclusions

FLRV_% is significantly predictive of PHLF after MH, with over half of patients with PHLF having FLRV_% < 30%. In light of this, we propose that all patients should undergo risk stratification prior to MH, with the high risk patients additionally being assessed with CT volumetry.

O-P01 Potential Utility of Intraoperative Fluid Amylase Measurement During Pancreaticoduodenectomy

Background

Postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) is a source of major morbidity and mortality. Early diagnosis and treatment of POPF is mandatory to improve patient outcomes, and clinical risk scores may be combined with postoperative drain fluid amylase (DFA) values to stratify patients.

The aim of this study was to determine if intraoperative fluid amylase values (IFA) correlate with DFA1 and POPF.

Methods

In consecutive patients undergoing PD between February and November 2020, intraoperative samples of intra-abdominal fluid adjacent to the pancreatic anastomosis were taken and sent for fluid amylase measurement prior to abdominal closure. Data regarding patient demographics, postoperative DFA values, complications and mortality were prospectively collected.

Results

Patient Demographics: Data was obtained for 52 patients with a median alternative Fistula Risk Score (aFRS) of 9.4. Postoperative complications occurred in 20 patients (38%), including five Clavien grade 3+. There were eight POPFs and two patients died (pneumonia/sepsis). There was significant correlation between IFA and DFA1 (Pearson’s correlation: R2=0.713; p &lt; 0.001) and DFA3 (p &lt; 0.001), and median IFA was higher in patients with POPF than patients without (1232.5 vs. 122; p = 0.0003). IFA&gt;260 U/l predicted POPF with sensitivity, specificity, PPV and NPV of 88%, 75%, 39% and 97%, respectively. The incidence of POPF was 43% in high risk (high aFRS/IFA) and 0% in low risk patients (low aFRS/IFA).

Complications:

Conclusions

Intraoperative fluid amylase closely correlated with postoperative pancreatic fistula, and may be a useful adjunct to clinical risk scores to stratify patients during pancreatico-duodenectomy, allowing targeted intervention to reduce the clinical impact of pancreatic fistula.It is possible to detect fluid amylase adjacent to the completed pancreatic anastomosis in patients undergoing PD. Presence of IFA correlates with postoperative DFA and POPF.

IFA increases the accuracy of the alternate Fistula Risk Score in predicting POPF. Low risk patients with a low IFA may be suitable for a ‘no drain’ strategy, whilst patients with a high IFA may benefit from intraoperative mitigation strategies to reduce the incidence and/or severity of a postoperative pancreatic fistula.

Survival Advantage of Upfront Surgery for Pancreatic Head Cancer Without Preoperative Biliary Drainage

Introduction

Level 1 evidence from randomized trials demonstrates less complication when jaundiced patients with resectable pancreatic cancer proceed directly to surgery, rather than undergo preoperative biliary drainage (PBD) first. Although "fast track" surgery significantly increases the resectability rate, it is unknown whether this translates into a survival benefit. This study evaluated the effect of upfront surgery on long-term survival using an intention-to-treat (ITT) analysis.

Methods

Patients were identified from a prospectively maintained database, stratified according to whether or not they underwent PBD.

Results

Among 157 patients, 84 (54%) underwent PBD. Of these, 73% underwent surgery, compared to 100% of those without PBD (p<0.001). Reasons for not undergoing surgery were progression of cancer (N=11), progressive frailty (N=5), or PBD-related complication (N=7). In those who underwent surgery, PBD was associated with a longer time from diagnosis to surgery (median: 59 vs. 14 days, p<0.001), and a higher rate of unresectable cancer at surgery (26% vs. 3%, p<0.001). On an ITT basis, patients treated with PBD had significantly shorter survival, at a median of 15 vs. 19 months (HR: 1.59, 95% CI: 1.07-2.37, p=0.023). However, for the subset of patients who underwent resection, survival was similar in the two groups (HR: 1.07, 95% CI: 0.66-1.73, p=0.773).

Conclusions

A reduced time to surgery with avoidance of PBD offers survival benefit. This is only appreciated on ITT analysis, which includes patients who are initially considered candidates for surgery, but ultimately do not undergo surgery. Considering this 'hidden' cohort of patients is important when considering optimal pathways for the treatment of resectable pancreatic cancer.