Laparoscopic Resection of a Giant Lumbar Foraminal Schwannoma

Lumbar foraminal schwannomas occasionally present as giant lesions in the retroperitoneal cavity. Here, we report a case of a L5 giant foraminal schwannoma that was laparoscopically excised. A 26-year-old man visited our hospital with the complaint of numbness of the left leg that had persisted for 2 years. Magnetic resonance imaging scans revealed a dumbbell tumor originating from the left L5/L6 intervertebral foramen. The tumor mass in the retroperitoneum extended to 6 cm and was buried in the iliopsoas, pressing superiorly on the L4 nerve root. During the surgical procedure, the ventral portion of the tumor was first excised outside the intervertebral foramen, using the anterior approach to laparoscopically enter the retroperitoneum. Postoperatively, the left leg pain disappeared. The residual tumor in the posterior portion was resected microsurgically with the Wiltse paraspinal approach. The tumor was a schwannoma originating from the dorsal ramus of the L5 nerve root. Postoperatively, the patient resumed ambulation and was discharged with no exacerbation of the neurological symptoms.