Long-term outcome of skull base surgery with microvascular reconstruction for malignant disease

Background: Successful resection of malignant skull base disease depends implicitly on the ability to reconstruct the resulting defects in the craniovisceral diaphragm, to support neural structures, and to prevent ascending intracranial infections. Microsurgery reliably achieves these objectives and has increased the scope of curative oncologic surgery. The authors assessed the reconstructive results and the long-term oncologic outcome of patients having skull base surgery with free tissue transfer. Methods: A retrospective review of cases between 1989 and 2001 was undertaken. Demographics, histology, surgical management, complications, locoregional control, and survival were analyzed. Results: Predominantly male patients (n=53;62 percent) with an average age of 60 years had microvascular reconstruction following oncologic surgery. There was a preponderance of cutaneous malignancies (56 percent), and most lesions involved the anterior skull base (53 percent). Tumors were mostly resected with a combined intracranial or extracranial approach, and reconstruction was undertaken with radial forearm, rectus abdominis, or latissimus dorsi flaps with 94 percent success. Complications occurred in 23 percent of patients, and no specific risk factors for developing intracranial complications were identified. Specifically, extensive reconstructions did not increase the complication rate. The 5-year locoregional control and survival rates were 74 percent and 60 percent, respectively. A positive resection margin significantly increased the risk of locoregional recurrence and worsened disease-specific survival on Cox regression. Survival was also influenced by grade of malignancy. Conclusions: Microsurgery is highly reliable for reconstructing defects resulting from oncologic resections of the cranial base. It can and should be undertaken using a small number of highly dependable flaps.