Selective Neck Dissection for Mesopharyngeal Squamous Cell Carcinoma.

In the present study, we retrospectively investigated states of occult metastases and lymph nodes with recurrent mesopharyngeal squamous cell carcinoma (MPSCC) to find an appropriate mode of neck dissection for MPSCC.Thirty-one patients with MPSCC who underwent neck dissection or were diagnosed with a recurrence in the neck lymph nodes following curative therapy were available for the present study. In cases of NO MPSCC (9 cases), occult metastases and recurrent nodes were mostly limited to ipsilateral levels 1 to 3. One case with recurrence on the lower border (hypopharynx) in the primary region had a reccurred node at level 6. In cases with a single swelling node (3 cases of N1 and 8 cases of N2a), metastases or recurrence never ocurred at level 5. In cases with multiple swelling nodes or a large (>6 cm) node (8 cases of N2b, 1 case of N2c and 2 cases of N3), metastases were spread through ipsilateral levels 1 to 5 but never occurred in contralateral level 5. In cases of lateral wall type, residual lymph node metastases after curative radiation therapy were observed in 3 cases. Consequently, we conclude that ipsilateral level 1 to 4 neck dissection is appropriate for NO mesopharyngeal cancer, ipsilateral or bilateral level 1 to 4 neck dissection for Nl and N2a cases, and ipsilateral level 1 to 5 and contralateral level 1 to 4 neck dissection for more than N2a cases. We also conclude that it is necessary in some cases of lateral wall type to perform neck dissection after curative radiotherapy.