[En garde, sentinel node!]. / inverted exclamation markEn guardia, centinela!

Injection technique and radiocolloid size are two critical parameters that must be carefully selected according to patient presentation and lesion appearance for accurate sentinel node detection in breast cancer. Scintigraphic detection and intraoperative localization are dependent on these parameters. The present clinical case illustrates how much deep intralesional tracer injection bears on our capacity to detect extra-axillary sentinel nodes and how the use of smaller-size radiocolloids may sometimes facilitate sentinel node detection.

[Radioisotopic localization of the sentinel lymph node in breast cancer. Preliminary results]. / Localiazación radioisotópica del ganglio centinela en el carcinoma de mama. Resultados preliminares.

The aim of this preliminary work is to show the results of the radioisotopic localization of the sentinel node in breast cancer and the surgical resection using a gamma probe. We studied 10 patients with breast cancer without primary chemotherapy and 3 patients with primary chemotherapy before surgery. A lymphoscintigraphy was made after injection of 111 MBq of Tc99m-nanocolloid in a volume of 3 ml. The scans were performed after 30 minutes, 2 hours, 4 hours and 24 hours after injection. We detected the node and then a skin mark was made. The next day, surgical resection of this node was performed, guided by a gamma probe. We detected all sentinel nodes but one: 12 sentinel nodes and 7 second echelon nodes. The mean time for a surgical detection was about 16 minutes. In our experience this technique allows an accurate localization of the sentinel node in patients with breast cancer. We are able to localize the node in the surgical room guided with gamma probe. The peroperatory evaluation by anatomopathological techniques shown the status of this node. All this, does not delay the surgical time.