Skull base surgery: the first 50 years

Abstract

It is nearly 50 years ago that Alfred Ketcham started his work on developing an operation for surgical removal of malignant tumors of the paranasal sinuses transgressing the anterior skull base. His Wrst report in 1963 opened the doors for modern day skull base surgery for malignant tumors involving the skull base [1]. Over the course of the past 40 years, tremendous advances in diagnostic imaging, neuronavigation and the development of technical instrumentation as well as operating microscopes and endoscopic equipment has revolutionized the surgical approach to neoplastic diseases transgressing the skull base. Numerous investigators from all parts of the world have reported signiWcant experience with the surgical technique. Five-year, disease-speciWc, survival rates in the range of 60% are reported by most investigators. In spite of the tremendous amount of technical and technological advances, improvement in survivorship, however has not been reported in the last four decades. Due to a large variety of tumors arising in this location, no single author or institution has suYcient experience to produce meaningful outcomes data for the more commonly arising conditions in this region. Therefore, an international collaborative study with participation of 17 investigators was undertaken, accumulating over 1,500 craniofacial resections done for neoplastic diseases. Cumulative data from this large study again show a 5 year disease-speciWc survivorship of 60%. Histology of the tumor plays a great role in prognostication. Esthesioneuroblastomas, and low-grade sarcomas have the most favorable outcome with 5 year disease-speciWc survivorship exceeding 80%. On the other hand, poorly diVerentiated carcinomas, high-grade sarcomas and melanoma have the worst prognosis with a Wve-year survivorship of 20%. All other histologies such as minor salivary gland carcinomas, squamous cell carcinomas and sarcomas have approximately a 60% 5 year survivorship. In a multivariate analysis of factors aVecting outcome, in addition to histology, intracranial extent of tumor (invasion of dura or brain) and positive margins were independent prognostic parameters inXuencing outcome. These data have provided benchmark statistics for comparison of any individual series or techniques in the future [2]. In this issue of European Archives, three articles are presented covering three diVerent topics pertaining to skull base surgery. PJ Donald presents in detail the contraindications for skull base surgery for malignancy. He rightfully points out anatomical boundaries for a safe surgical resection, tumor factors and tumor biology as well as patient factors, which will inXuence the decision for a safe surgical conduct. While anatomical limits of resection will be largely dictated by the extent of the tumor and the biology of local progression of the tumor, technical expertise and experience of the surgeon is equally important in accurately deWning the limits of resection. A heroic operation may be technically feasible, but the biology of the tumor may defeat such an undertaking. Surgical safety, patient tolerance, reduction in morbidity and anticipated life expectancy are all factors that should be considered in making a decision regarding operability of the tumor. If palliation is the goal of the operation, clearly the morbidity of the operation should not exceed the anticipated beneWt. We must not forget the basic dictum in any surgical endeavor of “primum non-nocere”. J. P. Shah (&) E W Strong Chair in Head and Neck Oncology, Chief, Head and Neck Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA e-mail: shahj@mskcc.org