Purpose: To compare tumor progression in both embolized and non-embolized liver lobes after portal vein embolization (PVE) in patients with bilobar colorectal liver metastases (CLM), according to the initial response to induction chemotherapy.
Methods: From 2002 to 2012, a total of 42 consecutive patients with bilobar CLM initially treated using induction chemotherapy underwent right PVE to achieve adequate future liver remnant volume. Tumoral and liver parenchyma volumes, as well as their volume variations, were measured on computed tomography before and after PVE in both embolized and non-embolized. Patients were classified as fast (≤6 cycles of induction chemotherapy) and slow (>6 cycles) responders.
Results: Overall, 432 metastases were analyzed in 42 patients. Patients were slow responders in 29 (69 %) cases. Tumoral volume increased in 29 (69 %) cases in the embolized liver (+48 %; p < 0.0001), and in 28 (66 %) cases in the non-embolized liver (+31 %; p < 0.0001). Fast responders had a tumoral volume decrease in both embolized (-4 %) and non-embolized (-9 %) lobes. On the opposite side, slow responders had tumoral volume increase in both embolized (+79 %) and non-embolized (+32 %) lobes. On multivariate analysis, a 'slow' response to induction chemotherapy was the only factor associated with tumoral progression in both embolized (p = 0.0012) and non-embolized (p = 0.001) lobes.
Conclusion: Tumor growth after PVE is observed in both embolized and non-embolized liver lobes in most patients but is significantly associated with slow response to induction chemotherapy.