Establishment and identification of a rabbit model of peritoneal carcinomatosis from gastric cancer.
BACKGROUND
Gastric cancer peritoneal carcinomatosis is a common clinical problem, but there are no suitable large animal models to study this problem. This study was to establish a stable rabbit peritoneal carcinomatosis model of gastric cancer using VX2 tumor, and analyze the clinico-pathological features.


METHODS
VX2 tumor was implanted into 36 New Zealand rabbits by 3 methods: laparotomic orthotopic injection of cancer cells into the submucosal layer of the stomach (Group A), laparotomic implantation of tumor tissue into the greater omentum immediately beneath the gastric antrum (Group B), and percutaneous injection of tumor cells directly into the peritoneal cavity (Group C), 12 rabbits in each group. The animals were closely observed and detailed clinico-pathological studies were conducted.


RESULTS
The success rates of peritoneal carcinomatosis formation were 100% (12/12), 91.7% (11/12) and 58.3% (7/12), respectively, for Groups A, B and C (P = 0.019, A versus C; P = 0.077, B versus C; P = 0.500, A versus B, Fisher's exact test). Two weeks after submucosal cancer cells injection in Group A, ulcerative gastric cancer with peritoneal carcinomatosis showed typical VX2 tumor pathology, with widespread intraperitoneal metastatic nodules, bloody ascites and perspicuous pulmonary metastases. The clinico-pathological progression pattern was very similar to patients of advanced gastric cancer with peritoneal carcinomatosis. Groups B and C showed similar pattern of cancer progression, but less aggressive.


CONCLUSIONS
First large animal model of peritoneal carcinomatosis from gastric cancer has been established by laparotomic orthotopic injection of VX2 cancer cells into the submucosal layer of the stomach, providing a more suitable model for surgical interventional studies. The clinico-pathological features of this model resemble human peritoneal carcinomatosis.
Mei
Lie-Jun
LJ
Department of Oncology, Zhongnan Hospital of Wuhan University & Hubei Key Laboratory of Tumor Biological Behaviors, Wuhan, 430071, China.
Yang
Xiao-Jun
XJ
Tang
Li
L
Hassan
Alaa Hammed Al-Shammaa
AH
Yonemura
Yutaka
Y
Li
Yan
Y
D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000556:secondary*; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D010534:Peritoneal Neoplasms / Q000556:secondary*; D011817:Rabbits; D013274:Stomach Neoplasms / Q000473:pathology*