Establishment of a rabbit uterine cancer model using VX2 tumor fragments

Preclinical uterine cancer models using the rabbit VX2 system have been described in previous studies; however, they often involve complex procedures such as cell culture, uterine suturing, or imaging validation. This study aimed to establish a technically simple and reproducible rabbit model of uterine cancer using VX2 tumor fragments.

We established a rabbit uterine cancer model by injecting minced VX2 tumor tissue into the endometrium of New Zealand White rabbits. We first generated VX2 tumors in donor rabbits via subcutaneous thigh injection and harvested them after three weeks. Recipient rabbits were assigned to two cohorts with scheduled assessments at 14 days or 4 weeks post-implantation. Tumor formation was assessed at each time point by intraoperative inspection and histopathological analysis.

In the initial 14-day cohort (n = 8), all rabbits developed well-defined uterine tumors without perioperative complications. Histological analysis confirmed viable tumor growth. No lymph node metastasis or distant spread was observed at the 14-day endpoint. In a separate, extended 4-week cohort (n = 8), all rabbits also developed uterine tumors. This cohort demonstrated tumor progression, with 75% exhibiting retroperitoneal lymph node metastasis, and 37.5% showing peritoneal metastasis.

This study demonstrates the feasibility and reproducibility of a simplified VX2 uterine cancer model using tumor fragments. Furthermore, the model replicates metastatic progression, including retroperitoneal lymph node and peritoneal metastasis, by 4 weeks. The model may serve as a reliable platform for future preclinical studies involving uterine tumor biology and metastatic progression.