How to dissect the para-hyoid lymph nodes for tongue cancer

Although the incidence of para-hyoid lymph nodes is not very high, ranging from 1.6％ to 8.0％, the salvage rate is remarkably low at 30％ when found as recurrence. In our own study of 315 cases of tongue cancer, the metastasis rate of the para-hyoid lymph nodes was 2.8％, the salvage rate was 14％ when found as recurrence, and the 2-year survival rate was 27.8％. Our technique requires only 5-10 minutes of surgery, with minimal blood loss and no complications, and it is thus considered acceptable to add elective para-hyoid lymph node dissection at the time of neck dissection for its control. However, the anatomical location of the metastasis was un-clear, and the extent of the dissection was not clear. Therefore, we reviewed 9 cases from our own experience and 36 cases from 22 papers, and found that metastasis around the lingual vein on the hyoglossus muscle was common. In this article, we describe the specific surgical method of para-hyoid lymph node dissection based on the clinical site of metastasis, and present a case in which metastasis was actually found after elective dissection.