Departments

Medical Departments

Nuclear Conventional Medicine

The Sentinel Lymph Node in Oncology (second part)

The ‘sentinel lymph node’ in clinical practice

In practice, it is very easy in Nuclear Medicine to detect and to see these ‘sentinel’ lymph nodes, which are nodes at risk. Actually, an injection of a radiomarked colloidal solution all around the tumour is enough. The material will flow in the lymphatic vessels coming out of the tumour and will accumulate in the nodes that end them. Therefore, the vessels and nodes can be easily seen and detected; images from them can be stored (scintigraphy) and / or they can be searched for in an operation theatre. For this purpose, probes are used to detect the radiation of the radioactive colloidal solution accumulated in the vessels and the nodes.

The day before the operation – or that very morning – some injections will be performed all around or within the tumour. It will be practised either by the physician in charge of the patient or by a physician specialized in nuclear medicine. Then, scintigraphic imaging will be captured just after the injections or after some time. They will be repeated just before the operation if necessary.
Once in the operating theatre, the surgeon will use the information revealed by the captured imaging to find the nodes. He will discern them more precisely with a probe that detects the emitted radiation.
In some cases, the surgeon may also inject a vital dye all around or inside the tumour so that he can directly see the lymph vessels and the nodes.

 

The ‘sentinel lymph node’ in breast cancer

With the team of Prof Jean-Marie Nogaret – made of Drs Hertens, Noterman, Veys and Schobbens –, our Institute was one of the first to launch that technique in Belgium and is now very experienced with it. It is used for 2 to 10 patients per week.

 

However, the clinical setting to apply the technique is carefully selected. At the current stage, the sentinel lymph node technique and its selective lymphadenectomy are limited to small isolated tumours (generally less than 2 cm at the palpation and less than 15 mm for the longest diameter when it was directly analyzed after having been removed in the operation theatre) and when any node was found at the palpation of the homolateral axillary cavity.

 

In breast cancer, the sentinel lymph nodes can be seen by order of frequency – i.e. within the axiliary cavity, next to or behind the sternum (internal mammary nodes), within the breast itself (intramammary), or next to it (external mammary nodes).
Link to the team of Mammary Surgery (Person in charge: Dr Nogaret)

 

The ‘sentinel lymph node’ in melanomas

Since 1998, the ‘sentinel lymph node’ technique in the melanoma has been exercised by Dr François Sales.
It is used for melanomas from 1 et 4 mm thick that does not show any detectable node in the nodal drainage areas. It is particularly useful for lesions located in the head and neck area, in the thorax, in the abdomen, in the pelvis and in the roots of the limbs. Actually, in these areas, the lymphatic drainage can be done towards several ganglionary groups which are all theoretically at risk. 

 

The ‘sentinel lymph node’ in ENT area cancers

The place of the ‘sentinel lymph node’ technique in ENT area cancers is being assessed by the team of Prof Guy Andry (Drs D. Desquanter and Lothaire ).

 

The ‘sentinel lymph node’ in prostate cancers

A lot of interesting prospects are also offered by the possibility to detect – in vivo – nodes at risk to be affected in case of prostate cancers.
The application and assessment of that technique to selected cases are being done by the team of Prof R. Van Velthoven.

 

Person in charge : Pr Patrick Flamen