Prospective study on neck dissection after primary chemoradiation therapy in stage IV pharyngeal cancer

Definitive chemoradiation is a well-established option in the treatment of locally advanced squamous cell carcinoma of the head and neck. The intention of this study was to evaluate its efficacy on cervical lymph node metastases in a prospective study after a standardized protocol for chemoradiation (CRT) and histopathological evaluation, respectively.

The data of 25 patients (10 oropharynx, 15 hypopharynx) who received planned neck dissection after definitive chemoradiation for UICC stage IV carcinomas of the pharynx were analyzed. All patients were sonomorphologically staged positive for lymph nodes (3 patients: N1; 2 patients N2a; 7 patients N2b; 9 patients N2c and 4 patients N3). A neck dissection was carried out 8.9+/-1.5 weeks (range 6-13) post treatment. The specimens obtained from the different neck levels were histologically examined for viable tumour cells.

Local control was achieved in 100% of all patients on endoscopy 9 weeks after the chemoradiation. In 14/25 patients (56%), still viable tumour tissue was found in the neck dissection (ND) specimen. Only one of these 14 patients (7%) was deemed suspicious for residual lymphadenopathy from clinical and diagnostic findings at re-staging after chemoradiation, the others were staged yN0. Postsurgical complications occurred in six patients (24%) such as bleeding and prolonged wound healing in one patient each and functional deficits in an additional four patients. One patient developed a scar recurrence seven months after surgery.

Based on these findings, the ultimate efficacy of primary CRT should not be judged 8-10 weeks after the treatment. Therefore planned neck dissection should be performed no earlier than 12 weeks after primary CRT.