Porto-sinusoidal vascular disorder in surgical candidates for liver metastases: Prevalence, non-invasive diagnosis, and burden on surgical outcomes.

Background & aims: Chemotherapy can cause vascular and metabolic liver injury in patients with liver metastases, but scarce data is available. We aimed to i) describe the prevalence of porto-sinusoidal vascular disorder (PSVD) among patients undergoing resection for liver metastases; ii) assess whether liver (LSM) and spleen stiffness measurements (SSM) could diagnose PSVD and predict post-operative complications.

Methods: This is a prospective single center study enrolling consecutive patients undergoing hepatic resection for metastases at a tertiary center. For each patient we evaluated previous exposure to chemotherapy, co-morbidities, elastography, type of surgery, histological features at the resection specimen, morbidity [post-hepatectomy liver failure (PHLF), major complications according to Clavien-Dindo], and 90-days survival.

Results: Sixty-eight patients were included, of whom 60 (88%) had received chemotherapy. Twenty-nine (44%) patients had PSVD. SSM <21 kPa (NPV 87%) and >40 kPa (PPV 100%) could accurately diagnose PSVD. PSVD significantly increased the risk of PHLF (22 vs 45%) and major complications (11 vs 31%). Pre-operative LSM was associated with post-operative morbidity. The cut-offs LSM <4.5 kPa and >8 kPa predicted the risk of clinically significant PHLF (0%, 11%, and 33% in LSM <4.5 kPa, 4.5-8 kPa,>8 kPa respectively) and major complications (0%, 25%, 44% in LSM <4.5 kPa, 4.5-8 kPa,>8 kPa, respectively).

Conclusions: PSVD is very common among patients undergoing liver surgery for metastases and it is associated with increased morbidity. LSM and SSM can correctly identify patients with PSVD and those at risk of clinically relevant post-operative complications.