Inflammatory myofibroblastic tumors of the central nervous system that express anaplastic lymphoma kinase have a high recurrence rate
A 26-year-old right-handed male presented with a 3-month history of mild headaches and blurred vision. He had a 10-year history of tobacco use. There were no other neurological symptoms. Neurological exam was normal except for right homonymous hemianopia. A contrast-enhanced computed tomography (CT) scan revealed an enhancing left temporal mass. Magnetic resonance imaging (MRI) showed a gadolinium enhancing extra-axial tumor, originating from the left tentorial incisure. The lesion had a supratentorial extension with significant mass effect and peri-lesional edema in the left temporal lobe []. Cerebral angiography demonstrated a poorly vascularized tumor. The preliminary diagnosis was that of a tentorial meningioma.\nIn order to prevent retraction of the temporal lobe and stretching the vein of Labbe, a supracerebellar transtentorial approach in the park-bench position was performed. Incision of the thickened posteromedial part of the left tentorium revealed a yellowish and fibrous tumor. The tumor was resected using standard microsurgical technique including intracapsular debulking and extracapsular dissection.\nNo new neurological deficit was found after the surgery. Immediate postoperative CT showed a 2.0 × 1.5 × 1.0 cm tumor remnant involving the lateral border of the tentorium []. The patient was discharged without steroids 1 week after the operation.\nHistopathological examination showed a predominance of spindled myofibroblasts arranged into fascicles surrounded by a diffuse inflammatory infiltrate of lymphocytes and plasmocytes []. This confirmed the diagnosis of IMT. Mitotic activity was evident and the proliferative index was estimated to be 20%. ALK expression was strongly positive. Knowing that some of these lesions might recur after many years, we opted for a close follow up.\nThe patient presented 2 months later with a new episode of headache and transient aphasia. A second MRI [] showed significant local tumor progression. Gross total resection was achieved through a supratentorial approach for the lateral aspect of the tumor and through an infratentorial approach for its medial part. There was no neurological deterioration and a radiotherapy treatment of 60 Gy in 30 fractions was promptly started after discharge. MRI taken 3 [], 6, and 10 months after the second surgery showed no residual lesion.\nTwenty months after his second surgery, the patient presented with aphasia, inappropriate laughter and increased aggressiveness. A head CT-scan with contrast showed a local recurrence with infra- and supratentorial extension [Figure and ]. The previous craniotomy was enlarged and a mastoidectomy was done to expose the transverse, sigmoid, and superior petrosal sinuses. The tumor was dissected from the temporo-occipital and cerebellar parenchyma and excised. Medial transverse sinus tumoral infiltration was macroscopically totally removed. Immediate and 2 months postoperative CT-scan with contrast showed no residual tumor. Pathological findings did not differ from the first surgery.