New t classification of ethmoid malignant tumors undergoing anterior craniofacial resection

Between 1987 and 1996 at the National Cancer Institute of Milan 130 patients with a malignant ethmoid tumor underwent an anterior craniofacial resection. In the absence of an universally accepted T staging system, we developed in 1993 the following classification: T l-tumor involving the ethmoid and nasal cavity sparing the most superior ethmoidal cells; T2-tumor with extension to or erosion of the cribriform plate, with or without erosion of the lamina papyracea and without extension into the orbit; T3-tumor extending into the anterior cranial fossa extradurally and/or into the anterior two-thirds of the orbit, with or without erosion of the antero-inferior wall of the sphenoid sinus, and/or involvement of the maxillary and frontal sinus; T4-tumor with intradural extension, or involving the orbital apex, the sphenoid sinus, the pterygoid plate, the infratemporal fossa or the skin. According to this classification we had: 48-T2. 33-T3, 49-T4 (no case of Tl was present in the series, since these rare small tumors did not undergo a craniofacial resection). Five-year overall survivals were: T2-64%, T3-48%. T4-21% (p <0.001). We classified these cases with the AJCC-1997 classification and we had: 15-T1. 10-T2, 40-T3, and 65-T4. Five-year overall survivals were: Tl-37%, T2-72%. T3-43%, T4-41%. Our classification seems to provide a better subdivision into different prognostic groups in comparison with the AJCC staging system.