Immunodeficient patients have an increased incidence of neoplasms, whether the immunodeficiency is due to genetic disorder, the acquired immunodeficiency syndrome (AIDS), or immunosuppressive therapy. Leiomyosarcoma (LMS) is a rare neoplasm, even if its incidence has increased because of AIDS. Less than fifteen cases were described after organ transplantation. An intracranial localization is exceptional (five cases in the literature) and was never described after organ transplantation, to our knowledge. Our present report focuses on a 45-year-old immunocompromised patient, who received immunosuppressive therapy for renal transplantation. He suffered from atypical peri-orbital headaches six months after transplantation and a mass involving the cavernous sinus was identified. Surgical biopsy was performed. Histologic examination revealed a LMS. Epstein-Barr virus was identified by quantitative polymerase chain reaction in the LMS. Immunosuppression was reduced, the patient received adriamycin and protontherapy was realized. He died two years after the transplantation because of tumor progression and kidney failure.