Surgical treatment of vena cava leiomyosarcomas: Series of cases in a referral center and literature review José Manuel Pérez-de-Villar; Alvaro Arjona-Sanchez; Blanca Rufián-Andujar; Francisca Valenzuela-Molina; Juan Manuel Sánchez-Hidalgo; Lidia Rodriguez-Ortiz; Angela Casado-Adam; Cristina Viyuela-García; Sebastián Rufián-Peña; Teresa Caro-Cuenca; Alberto Moreno-Vega; Javier Briceño-Delgado;