Four patients with cancer of ethmoid with extension to base of skull were treated by total ethmoidectomy through a subfrontal and transmaxillary approach, the complementary paralateronasal approach being necessary in only one case. Apart from the approach routes, particular features of the technique used were essentially the size of the frontal flap extending to orbital roof, and mainly the confection of a pericranial flap formed of epicranial aponeurosis lined with frontoparietal periosteum and pedunculated at the orbital border. Exposure of the tumor by the neurosurgical and sublabial transmaxillary route allows correct excision of cancers extending to cribriform plate. The pericranial plate completes the traditional base of skull plastic operation and appears to reduce risk of cerebromeningeal complications. The technique is proposed for cancer infiltrating meninges: it is valid whatever the age of patients.