Persistent carcinoma of the oropharynx and oral cavity re-treated by after-loading interstitial 192Ir implant.

After-loading implantation techniques apparently offer an effective alternative in the management of persistent (or recurrent) oropharynx and oral cavity carcinoma postirradiation. A total of 29 patients with such lesions was treated from February 1974, to July 1975, in the LAC/USC Radiation Medicine Section, using after-loading 192Ir implantation techniques. These patients all had extensive persistent cancer after "full tolerance" irradiation (with or without previous surgery) and were referred for palliation or for possible salvage. Additional doses administered ranged from 5000 to 7000 rads in three to five days. Eighteen of the 29 patients (63%) have had complete local control for 18 to 36 months. These patients have maintained a relatively satisfactory palliative status. Ten of the 29 are dead. Follow-up periods are short, but early indications are that problem patients with persistent cancer after "full tolerance irradiation" can be salvaged, or at least satisfactorily palliated, with after-loading interstitial implant techniques. Clinical details, sites of involvement, implantation techniques, dosimetry methodology, reactions and complications will be described.