Strength and limitations of the study
The strength of this meta-analysis is represented by its systematic and quantitative assessment of the role of prophylactic neck dissections in TBSCC using a strict inclusion and exclusion criteria. Our limitations include the low number of cases reporting the level of metastasis in the neck and the fact that the rates of occult nodal metastasis reported in the literature could be underestimated as not all cN0 patients underwent a neck dissection. From a statistical point of view, this meta-analysis has the limitation of having only observational and retrospective studies included. Furthermore, there are a relative low number of cases in some of the studies predominantly as a result of the rarity of these malignancies. Further limitations of our study include:
(a) Insufficient of data for a statistical analysis on the prevalence of occult metastases in each of the different lymph node levels
b) Inability to determine whether selective neck dissection is better than radiotherapy.
c) The inclusion criteria for many studies were not specified. This resulted in the exclusion of 17 studies in the final phase of review.
It would be helpful to perform a prospective multicentre study to compare the effectiveness of elective neck dissection and radiotherapy in TBSCC cN0 necks as data from individual units are unlikely to be sufficiently powered to influence overall management.