In addition to tumor size, its type or histology often do not affect how the disease is approached endoscopically, said Dr. Citardi. Regardless of tumor type, its removal is usually the same, he said.
Explore this issue:November 2007
Carl Snyderman, MD, professor of otolaryngology and neurological surgery and co-director of the Center for Cranial Base Surgery at the University of Pittsburgh School of Medicine, uses an endonasal approach for tumors involving the ventral skull base below the anterior brain or arising in the nasal passages. Examples include olfactory neuroblastomas, meningiomas, pituitary tumors, angiofibromas with intracranial extension, and inverted papilloma with skull base involvement.
Treating malignant nasal tumors that involve the skull base and intracranial tumors, both benign and malignant, can be controversial, added Dr. Snyderman. Some physicians express concern about using the procedure for malignancies because oncologic principles need to be applied to these growths to achieve complete resection without compromising margins.
However, a multidisciplinary team approach can ensure appropriate management of these tumor types, he explained, adding that only a handful of institutions are performing these surgeries.
One advantage of endoscopic skull base surgery is that it is minimally invasive, said Dr. Batra. Additionally, the rigid endoscope is a tool that provides brilliant illumination and magnification to detect tumor origin and boundaries and allows surgeons to see around corners. The endoscope allows superb exposure to the sphenoid sinuses, frontal recess and frontal sinus, and the orbital apex, said Dr. Batra, adding that this, in turn, aids with precise tumor removal.
The endoscopic approach to skull base surgery improves visualization, agreed Dr. Snyderman. However, he views the procedure as being maximally, not minimally, invasive. “The endoscope has extended the limits of skull base surgery, and we’re getting to areas we couldn’t get to before,” he said. “It’s maximally invasive but avoids the morbidity of extracranial approach.”
When compared with open skull base procedures, the endoscopic approach not only reduces morbidity but also provides similar overall survival and disease-free survival in published reports, said Dr. Citardi. Furthermore, endoscopic techniques are associated with less time in the hospital for the patient, he added.
In many cases, the endoscopic approach can also provide cosmetic benefits versus open surgery, said Dr. Snyderman.
Moreover, larger skull base surgeries being performed endoscopically help to reduce the need for some free flaps, said Dr. Stack. These procedures leave more local tissue available for reconstruction, and these defects have also been successfully repaired with allografts, he said.