Evaluation of the importance of a systematic neck dissection in carcinomas of the oral cavity treated by brachytherapy only for the primary lesion (about a series of 346 patients)

The study includes 346 carcinomas of the oral cavity (244 mobile tongues and 102 floors of mouth) treated by brachytherapy alone at primary tumor. We noted 199 T1, 131 T2, 14 T3 and 2 TxNx. Among T1, 36 patients had a neck dissection as well as 73 T2. Brachytherapy was performed according to the Paris system. In 59 cases, the picking on the lesion side was a radical neck dissection, in 14 cases a functional neck dissection and in 45 cases a sub-maxillary and sub-mental dissection. A combined controlateral neck dissection was performed in 20 cases. A complementary irradiation of the node areas was given in 28 cases. Results: for T1, the local control (LC) is 96 %, the locoregional control (LRC) 83 %, the specific survival (SS) 88 %, and the overall survival (OS) 73%. For T2, LC 85 %, LRC 70 %, SS 75 %, OS 52 %. For T3, LC 64 %, LRC 44 %, SS 25 %, OS 18 %. The difference is very significant between T1 T2 T3 (p<0,006) for results concerning NO, it is not significant between the N1 in each category, but their number is too low to reach a degree of significance. In the 36 neck dissection specimens of T1, we found only in 7 cases positive nodes and in the 73 specimens of T2, 24 cases of positive nodes. A detailed study is reported. Tumoral, node or both recurrences are summarized (see table IV). Node recurrences are more frequent in patients without neck dissection than in those with neck dissection for T1, T2, NO, but this is significant only for LRC, SS and OS between patients with negative nodes on neck dissection and those with positive nodes (p<0.0001). No significant difference was found between OS and SS for patients T1, T2, NO with positive systematic neck dissection and those with a neck dissection differed until the node recurrence, Among T1, T2, T3, we noted more metastases in patients who presented a recurrence. (authors). 35 refs., 4 tabs