J Neurol Surg B
DOI: 10.1055/s-0039-3402034
Original Article
Georg Thieme Verlag KG Stuttgart · New York

Skull Base Invasion Patterns of Malignant Head and Neck Tumors: A Neurosurgical Perspective

Kenichiro Iwami
1  Department of Neurosurgery, Aichi Medical University, Aichi, Japan
,
Masazumi Fujii
2  Department of Neurosurgery, Fukushima Medical University, Fukushima, Japan
,
3  Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan
,
Takashi Maruo
3  Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan
,
Yasushi Fujimoto
3  Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan
,
Keisuke Takanari
4  Department of Plastic and Reconstructive Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
,
Yuzuru Kamei
4  Department of Plastic and Reconstructive Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
,
Masayuki Yamada
2  Department of Neurosurgery, Fukushima Medical University, Fukushima, Japan
,
Tetsuya Ogawa
5  Department of Otorhinolaryngology, Aichi Medical University, Aichi, Japan
,
Koji Osuka
1  Department of Neurosurgery, Aichi Medical University, Aichi, Japan
,
Kiyoshi Saito
2  Department of Neurosurgery, Fukushima Medical University, Fukushima, Japan
› Author Affiliations
Funding This work was supported by Grant-in-Aid for Young Scientists (B) 15K19976 to Dr. Iwami from the Japan Society for the Promotion of Science.
Further Information

Publication History

31 July 2019

09 November 2019

Publication Date:
08 January 2020 (online)

Abstract

Objective Craniofacial resection (CFR) and temporal bone resection (TBR) on malignant head and neck tumors (MHNTs) invading skull base require accurate and precise determination of the tumor invasion. We investigated tumor skull base invasion patterns and surgical results in CFR and TBR cases.

Methods We performed either CFR or TBR for 75 selected patients with the possibility of en bloc resection over the period between 2011 and 2018. The medical charts of the selected patients were reviewed.

Results Primary tumor onset site (TOS) groups were: (1) nasal cavity/ethmoid sinus, 20 cases; (2) orbit, 10 cases; (3) maxillary sinus, 28 cases; and (4) external ear/temporomandibular joint, 17 cases. Grades for tumor invasion depth (TID) included: (I) extracranial invasion and skull base bone invasion; (II) extradural invasion; or (III) intradural invasion. Patients in groups 1 and 2 had a significantly higher frequency of grade II and III invasions than patients in groups 3 and 4. The main invasion site was nasal cavity superior wall and ethmoid sinus superior wall for group 1 tumors, orbit superior wall, and lateral skull base sphenoid bone for group 2 and 3 tumors, and lateral skull base temporal bone for group 4 tumors. Positive resection margins represented a significant negative prognostic factor. TID and TOS did not affect skull base margin status.

Conclusion Skull base invasion of MHNTs exhibits certain fixed patterns in sites susceptible to invasion based on the TOS. The frequencies of extradural and intradural invasions differed, indicating the importance for accurate preoperative tumor evaluation.

Disclosures

The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.