Primary leiomyosarcoma of the psoas in a patient with Neurofibromatosis type 1

• Main Author: Siham Mansouri (Author)
• Format: Book
• Published: Our Dermatology Online, 2018-07-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 2081-9390
• Keywords: Neurofibromatosis type 1; Leiomyosarcoma; Psoas; Dermatology; RL1-803
• Source: Nasza Dermatologia Online, Vol 9, Iss 3, Pp 296-298 (2018)

Neurofibromatosis Type 1 (NF1) is an autosomal dominant disorder that reduces the effectiveness of the neurofibromin tumor suppressor, resulting in an increased risk for benign and malignant soft tissue tumors. Leiomyosarcoma has been infrequently observed in NF1 patients. This case adds to the limited number of leiomyosarcomas reported in NF1 patients. This particular malignancy presented in a highly unusual location. A 15-year-old male with a previous diagnosis of NF1 presented a 3-month history of right-sided lumbago. Pelvic MRI revealed a large parenchymatous mass (69x66x115mm) in contact with the right psoas muscle. A biopsy guided by the scanner was performed. Histological examination with diffuse positivity of tumor cells for immunohistochemical muscle markers revealed high-grade leiomyosarcoma. A neoadjuvant chemotherapy was started based on Fluorouracil. The evolution was marked by the death of the patient 04 months later. To our knowledge, this is the first report of an NF1 patient who developed a primary leiomyosarcoma of the psoas. These rare tumors should be further evaluated. A careful follow-up of these patients is essential.