Ivan V Fedoriv, MD1, Ignacio Garcia-Alonso, PhD2, Mikel Gonzalez-Arribas, Student2, Inigo Cearra, MD2, Asier Santamaria, Student2, Borja Herrero de la Parte, MSC2. 1Department of human anatomy, operative surgery and topographic anatomy IFNMU, Ivano-Frankivsk, Ukraine, 2Dpt. of Surgery and Radiology. Faculty of Medicine UPV/EHU. Leioa, Spain
INTRODUCTION. Partial hepatectomy (PH) is the best therapeutic option for patients with liver metastases. However, liver resection causes the release of growth factors (GF), which can promote the proliferation of the tumoral cells still present in the patient. In this study we have evaluated the effect of PH on the growth of liver metastases after intrasplenic cell inoculation.
METHODS AND PROCEDURES. Under isofluorane anesthesia, a midline laparotomy was performed for clamping the left lateral lobe artery (LLA) of 18 WAG/RijCrl male rats. After that, tumour induction was done by seeding 250.000 syngeneic CC-531 cells into the spleen; five minutes later splenectomy was performed in all animals and after another 10 minutes the clamp of the LLA was removed and, in the PH-group, the left lateral lobe of the liver was excised (9 rats). Thereafter, the abdominal cavity was close.
Three weeks after cell seeding, the animals were examined using ultrasound (US) to evaluate tumour progression; 7 days later, all the animals were sacrificed and the liver was removed and placed in paraformaldehyde. Each lobe was cut into 1 mm sections to measure metastasis and total hepatic surface.
RESULTS. All animals inoculated with CC-531 cells developed liver metastases. The percentage of liver surface covered with metastases was statistically significantly higher in the animals that were subjected to partial hepatectomy, compared to animals which were not hepatectomised (46.98 ± 8.76% vs. 18.73 ± 5,65%; p<0.05). The right lateral lobe (RL) showed no difference in both hepatectomised and no hepatectomised animals (45.38 ± 11.24% vs. 32.69 ± 10.19%; p>0.05). The paramedian (PL) and caudate lobe (CL), showed significant differences in liver surface occupied by metastases in both groups of animals.
Finally, analyzing the left lateral lobe (LL) surface of non-hepatectomized animals occupied by metastases, it may be seen that it is statistically significantly lower than any of the other lobes, only 7.28 ± 2.55%.
CONCLUSIONS. In this experimental model, the process of seeding & growth of colorectal cancer cells in the liver clearly benefits from the growth factors produced following partial liver resection.