Pelvic mass in von Recklinghausen's neurofibromatosis: diagnostic issues: a case report

BACKGROUND Leiomyomas are benign smooth muscle cell tumours. They are the most common uterine neoplasms, although they may also occur elsewhere, such as in the gastrointestinal and urinary tracts. Leiomyomas are uncommon in von Recklinghausen's neurofibromatosis (NF1). However, the literature suggests that the association of NF1 and leiomyomas or leiomyosarcoma is not entirely coincidental. CASE REPORT We report here the unusual case of a 47-year-old woman with NF1 who presented menorrhagias and a hard, tender pelvic mass composed of uterine leiomyomas. Positron emission tomography/computed tomography disclosed an area of increased 18-fluorodeoxyglucose (FDG) uptake in the upper right part of the mass that raised the suspicion of malignancy. Magnetic resonance imaging revealed numerous intramural leiomyomas ranging from 1 to 6 cm, including a 6-cm submucosal leiomyoma that had abundant cellularity, matching FDG uptake. Abdominal hysterectomy was performed and microscopic examination confirmed the diagnosis of multiple benign smooth muscle tumours (uterine leiomyomatosis). CONCLUSION Our case illustrates several diagnostic issues that arose while exploring this pelvic mass. Moreover, the association of uterine leiomyoma and NF1 may not be fortuitous.