Interstitial iridium 192 for cutaneous carcinoma of the external nose.

Several implantation techniques useful for nasal skin carcinoma have been developed at the Henri Mondor Hospital in Créteil, France and are described in detail. Iridium 192 wires, 0.3 mm in diameter, are afterloaded into either supple plastic tubes or rigid needles implanted according to the rules of the Paris system. Dosimetry is performed by computer, based on either direct measurements of active lengths and spacing, orthogonal films or a tomogram oriented in the central plane of the implant. According to a recent review by the European Curietherapy Group of 468 implants, the optimal dose is 60 Gy. The overall failure rate was 2.6%. Indications for implantation and choice of technique, based on tumor size, site, and gross morphology are discussed.