Table 1 Advantages and disadvantages of OSNA

Fast, objective, automated, and reproducible technique

Not valid for non-CK19 expressing tumours

Intraoperative analysis

Trained pathologist needed (thorough dissection)

Analysis of the whole LN

Potential contamination of the sample

Quantitative analysis:

• Cut-off points for macro and micrometastases

• TTL: potential predictive and prognostic factor

Not applicable in case of coexisting neoplasms with the same LN drainage

Ability to a more accurate identification of micrometastases

No tissue left to re-analysis (except RNA-based molecular tests)