Skull Base as a Team Sport: Role of the Neurosurgeon in Complex Head and Neck Cancer Surgery Requiring Vascularized Tissue Transfer Reconstruction

Introduction: Vascularized free-tissue transfer reconstruction has revolutionized the surgical treatment of complex head and neck cancers managed primarily by otolaryngologist, head and neck surgeons. At times, pathologies encroach upon the skull base or calvarium, requiring neurosurgical expertise in achieving total resection and adequate repair of exposed neural elements prior to free-tissue transfer reconstruction. Herein, we review the indications, techniques, and outcomes of a multidisciplinary team performing resection and free-flap reconstruction of complex head and neck cancer pathology.

Methods: After institutional review board approval, we retrospectively reviewed our departmental database of tissue transfer head and neck surgery patients from July 2013 to June 2019. Procedures utilizing both a neurosurgeon and otolaryngologist, head and neck surgeon were selected for further analysis from the electronic medical record. Representative cases were chosen for technique description.

Results: We identified 31 eligible patients who underwent 49 operations over the study period. 22 patients were male and 9 were female, with a median age of 60.4 ± 17.1 years. Anatomic regions for resection/repair were varied; the most common were the anterior fossa, middle fossa, and calvarium. Neurosurgical techniques for oncological resection, negative margins, and/or preparation of region for reconstruction included bony skull resection (40.8%), bone and dural resection (16.3%), and intradural tumor resection (28.6%) with or without reconstruction of these various layers. All patients then underwent free-tissue transfer by the ENT team to cover the surgical defect. The anterolateral thigh free-tissue transfer vascularized flap was most commonly used (35% of flaps in the cohort). Complications were not uncommon due to the complexity of the procedures performed. Most operative complications were flap related. Prior radiation was not a risk factor for postoperative complications. Neurosurgical complications included three postoperative CSF leaks, one seizure, and four intracranial hematomas. Unexpected new neurological deficits were rare, although seven patients suffered expected neurological deficits from resection of affected neural elements such as the orbital contents or cranial nerve(s). The median overall flap survival of our cohort was 13.8 months after surgery.

Conclusion: Neurosurgeons have unique skills in resection and repair that aid the multidisciplinary management of complex head and neck cancers encroaching upon the calvarium and skull base. A variety of techniques ranging from simple craniectomy and skull resection to microsurgical transorbital extradural middle fossa exposure and resection of Meckel's cave contents, allow for maximal safe resection of these highly morbid pathologies. Complication and flap revision rates are congruent with the level of defect complexity and prior radiation treatment.

Fig. 1 Defects from team approach oncological resections. (A) Right orbital exenteration has been performed for squamous cell carcinoma. Neurosurgery then performed a trans-orbital craniectomy to resect lateral orbit and orbital roof back to negative-margin frontal lobe and temporal lobe dura (FLD, TLD). Free flap reconstruction was performed thereafter. (B) A giant squamous cell carcinoma of the parietal scalp previously treated with radiation and subsequent development of osteoradionecrosis has been resected. Affected dead bone was resected 1 cm down to healthy bony bleeding (arrows), and free-flap reconstruction was performed thereafter.