Induction of Tumor Growth After Preoperative Portal Vein Embolization: Is It a Real Problem?

Abstract

Although preoperative portal vein embolization (PVE) is an effective means to increase future remnant liver (FRL) volume, little has been published on possible adverse effects. This review discusses the clinical and experimental evidence regarding the effect of PVE on tumor growth in both embolized and nonembolized liver lobes, as well as potential strategies to control tumor progression after PVE. A literature review was performed using MEDLINE with keywords related to experimental and clinical studies concerning PVE, portal vein ligation (PVL), and tumor growth. Cross-references and references from reviews were also checked. Clinical and experimental data suggest that tumor progression can occur after preoperative PVE in embolized and nonembolized liver segments. Clinical evidence indicating possible tumor progression in patients with colorectal metastases or with primary liver tumors is based on studies with small sample size. Although multiple studies demonstrated tumor progression, evidence concerning a direct increase in tumor growth rate as a result of PVE is circumstantial. Three possible mechanisms influencing tumor growth after PVE can be recognized, namely changes in cytokines or growth factors, alteration in hepatic blood supply and an enhanced cellular host response promoting local tumor growth after PVE. Post-PVE chemotherapy and sequential transcatheter arterial chemoembolization (TACE) before PVE have been proposed to reduce tumor mass after PVE. We conclude that tumor progression can occur after PVE in patients with colorectal metastases as well as in patients with primary liver tumors. However, further research is needed in order to rate this risk of tumor progression after PVE.Preoperative portal vein embolization (PVE) is an accepted intervention in patients requiring major liver resection in whom the estimated future remnant liver (FRL) is too small to allow safe resection.1,2 PVE induces atrophy of the embolized, tumor-bearing liver lobe while compensatory hypertrophy of the nonembolized lobe occurs, thereby increasing FRL volume and function.

Risk factors of early recurrence after curative hepatectomy in hepatocellular carcinoma

“…24,25 In addition, tumor necrosis could result in release of a large number of proinflammatory cytokines, which stimulate tumor growth, and therefore correlate with a poor prognosis. 26,27 Tumor necrosis has been reported to have prognostic value in many solid caner types, such as colon, lung, 25 breast, 28 and renal malignancies, including both renal cell carcinoma 29,30 and upper urinary tract urothelial carcinoma. 24 Although several studies have evaluated tumor necrosis as a prognostic factor for recurrence or survival in HCC, these studies have not shown a significant correlation between tumor necrosis and ER.…”

Comparison of the Effectiveness of Preoperative Portal Vein Embolization in Patients with Chronic Liver Disease: Gelfoam versus Gelfoam-Coil Combination

“…Hayashi et al (26) reported that the median tumor growth rate of primary liver cancer in the embolized lobe after PVE was approximately two times greater than that before PVE. Three possible mechanisms have been proposed: changes in cytokine and growth factor secretion, alteration in hepatic blood flow, and enhanced cellular host response that promotes local tumor growth (27). To the best of our knowledge, few studies have compared the tumor growth rate according to the embolic materials used.…”

Comparison of percutaneous transhepatic portal vein embolization and unilateral portal vein ligation

“…However, PVL is currently more often performed in TSHP cases requiring portal vein occlusion. Time between the first stage and PTPE should be minimized because of possible cancer pro gression [24,25] . Therefore, we recommend PTPE for the first part of TSHP.…”