Reirradiation of nasopharyngeal carcinoma with intracavitary mold brachytherapy: an effective means of local salvage.

Abstract

To assess the role of intracavitary mold brachytherapy in salvaging local failure of nasopharyngeal carcinoma (NPC). The outcomes of 118 consecutive NPC patients with local failure treated with mold brachytherapy between 1989 and 1996 were retrospectively reviewed. Eleven patients received additional external radiotherapy. All molds were tailor-made, and the whole procedure was performed under local anesthesia. Pharyngeal recess dissection was routinely performed to allow direct contact of the radioactive source with the pharyngeal recess, a common site of local failure. Initially, the molds were preloaded with 192Ir wires, but since 1992, the sources have been manually afterloaded; the mold has also been redesigned for better conformity, ease of insertion, and radiation safety. Using brachytherapy alone, 50-55 Gy was given for recurrence in 4-7 days; for persistence, 40 Gy was administered. The overall complete remission rate was 97%. The rates of 5-year local control, relapse-free survival, disease-specific survival, overall survival, and major complication were 85%, 68.3%, 74.8%, 61.3%, and 46.9%, respectively. Major complications included nasopharyngeal necrosis with headache, necrosis of cervical vertebrae with atlantoaxial instability, temporal lobe necrosis, and palsy of the cranial nerves. The afterloaded mold was as effective as the preloaded version, but with fewer complications. Intracavitary mold brachytherapy was effective in salvaging NPC with early-stage local persistence or first recurrence.