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Surgery for a large obstructive pelvic tumour associated with neurofibromatosis

Dear Sir, Patients with neurofibromatosis type 1, also known as von Recklinghausen’s disease, rarely present with obstructive lesions. A 19-year-old woman was admitted to the colorectal unit for rectal obstruction, urinary retention, pelvic heaviness and a suprapubic mass on examination. Her brother had undergone resection of three anterior thoracic subcutaneous benign tumours and her mother had been operated on for a meningioma. Emergency CT scan examination showed a 19 cm 9 15 cm 9 14 cm heterogeneous pelvic mass originating from the sacrum, pressing the bladder and uterus to the front, the sigmoid colon to the right, and the rectum to the back, explaining the obstruction. Selective angiography with three-dimensional reconstruction demonstrated that vascularization of the tumour originated from the posterior branch of the left arteria iliaca interna, showed an early venous drainage and permitted embolization to decrease the bleeding risk the morning before operation. The characteristics of the tumour, including hypervascularization, encapsulation and early venous drainage without arteriovenous shunts, favoured the diagnosis of benign neurofibromatosis. The pelvic tumour was removed surgically by laparotomy, using thermofusion. The pathological result was plexiform neurofibroma and the diagnosis of von Recklinghausen’s disease was ultimately made. The patient was relieved of obstructive symptoms but presented with a partial left lower limb paralysis for 7 months. Neurofibromatosis type 1 is a common autosomal dominant condition occurring in approximately one in 2500 births [1]. It is associated with gastrointestinal neoplasms in 2–25% of patients [2,3]. The lesions consist of an overgrowth of neural tissue along with other mesenchymal elements. Gastrointestinal tumours may present with complications such as haemorrhage [4], perforation [5] and very rarely obstruction [6–8]. This case is the second report of a type 1 neurofibromatosis patient with a compressive pelvic mass that was responsible for urinary and rectal retention, the first one being due to a neurofibrosarcoma [9].