Incidence of occult cervical metastasis in head and neck carcinomas: development over time

With the development of imaging techniques in diagnostics of head and neck carcinomas, especially computed tomography and ultrasonogaphy, one might expect that the incidence of occult metastases would be reduced. The aim of this study was to determine the rate of occult metastases in a large population cohort and explore its changes with improvement of imaging techniques over the last 30 years.

All patients between 1980 and 2010 with head and neck carcinoma and cN0 neck status were retrospectively evaluated. Six hundred thirty-six patients with cN0 neck who received an elective neck dissection as part of a definitive surgical treatment were included.

The overall rate of occult metastases was 24.8% (158/636). The rate was 26.5% (80/302) between 1980 and 1995 and 23.4% (78/334) between 1995 and 2010. Only pT1-2 glottic carcinomas had an occult metastases rate of less than 10%. All other pT1-2 carcinomas had an incidence of occult metastases between 19.1% and 42.5%. pT3-4 tumors showed an occult metastases rate of 24.5-53.3%.

The occult metastases rate showed only a marginal improvement over the last 30 years and is still above the 20% margin. All but pT1-2 glottic carcinomas should be considered for elective treatment of the neck.