Definitive radiation treatment for early stage carcinoma of the soft palate and uvula: the indications for iridium 192 implantation.

ABSTRACT

From 1971 to 1984 59 T1 and T2 carcinomas of the soft palate and uvula were treated definitively by irradiation at the Henri Mondor hospital. Included are ten patients previously irradiated to the oropharyngeal area for either a carcinoma of the soft palate or another malignancy. Sixteen patients were treated by external irradiation alone, 14 by Iridium 192 implantation, and 29 by a combination of the two. Two techniques of implantation were used the guide gutter technique (33 patients) and the plastic tube technique (10 patients). Clinically negative neck nodes (51/59) either received prophylactic telecobalt therapy (39/51) or were surveilled (12/51). Clinically involved nodes (8/59) were managed either by external irradiation alone (4/8) or combined with neck dissection (4/8). Local failure was 25% (4/16) after exclusive telecobalt therapy, 18% (5/19) after combined telecobalt therapy and implantation, and 0% (0/14) after Iridium 192 implantation alone. No local failures were seen with the plastic tube technique (0/10) as compared to 15% (5/33) for guide gutters. Only two nodal failures were observed (2/59 3%). Crude 5-year disease-free survival was 33%. Severe complications were limited to one osteonecrosis, one soft tissue necrosis, and one partial palatal incompetence. Salivary impairment was reduced when implantation was used for part or all of the treatment. We recommend 45 Gy external radiation followed by 30 Gy from Iridium 192 implantation using the plastic tube method unless there has been prior oropharyngeal irradiation, in which case we give 60 Gy from implantation alone. For clinically negative neck nodes, we recommend 45 Gy prophylactic external neck irradiation. For clinically positive lymph nodes, this should be followed by either a 25 to 30 Gy boost to the involved nodes or a neck dissection.