Tumor seeding incidentally found two years after robotic-Assisted radical nephrectomy for papillary renal cell carcinoma. A case report and review of the literature.

INTRODUCTION: Port-site metastasis or peritoneal spread after laparoscopic surgery for urological malignancies is a rare phenomenon accounting for 0.09% and 0.03% of the cases respectively. PRESENTATION OF CASE: We present a case of tumor seeding in the omentum found in a female patient after previous transperitoneal robotic-assisted radical nephrectomy (RARN) for papillary renal cell carcinoma (RCC). Two years after the robotic operation, the patient was diagnosed with cervical clear cell carcinoma and underwent radical hysterectomy with lymphadenectomy and omentectomy. A neoplastic omental nodule was incidentally identified intraoperatively. Pathological characteristics and immunohistochemistry revealed features of papillary RCC. Two years after the hysterectomy, the patient is clinically cancer free, without any adjuvant therapy for her cervical cancer. DISCUSSION: To the best of our knowledge, we report the first case of tumor seeding in the omentum following RARN for organ confined low grade papillary (T2aN0M0) RCC. No risk factors that could explain the tumor seeding were identified. The neoplastic cells had a low proliferative index (Ki-67<5%) and a decreased capability to metastasize.
CONCLUSION: Tumor seeding as a result of robotic assisted laparoscopic nephrectomy, although rare, might represent a novel way of tumor inoculation deprived of or with low malignant potential.