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eComment. Criticism on a new marking technique for lung nodules identification.

We have read with interest the paper by Kawada and colleagues focusing on the preoperative marking of small lung nodules resectable by thoracoscopic wedge resection [1]. As the authors underline, various marking procedures for localization have been already described. However, each one of these techniques is affected by different disadvantages [2]. When a preoperative marker is needed, we usually use the percutaneous CT-guided hook-wire placement method. We are conscious that this procedure is affected by possible complications such as pneumothorax, haemothorax, air embolism, and the disadvantages of an additional radiation exposure. In our experience with hook-wire placement, we only observed pneumothorax, usually low entity. However, chest tube placement is always required to avoid tension pneumothorax during mechanical ventilation at the subsequent surgical operation. Therefore, we think that the first advantage of the intrathoracic stamping method proposed by Kawada and colleagues is avoidance of the risks associated with visceral pleural puncture. The second possible advantage we identify in this method is that the use of an opaque marker lying on the skin, instead of a percutaneous hook-wire, reduces the possibility of accidental marker removal before surgery, and allows placement one or two days before operation. Lastly, although we do not have experience with the stamping method, we think that, in the event of adhesions, thoracoscopic pleural debridement could be performed more easily without a hook-wire inside the chest cavity. We identified as a possible disadvantage, the need to place the patient in the same position during CT scan and surgery, with the risk of dye spreading inside the pleural cavity, hence losing marking precision. In conclusion, we congratulate the authors who have described this new method. More data should be useful to definitively confirm its utility and safety. 
 
Conflict of interest: none declared