Sentinel Lymph Node Biopsy (SLNB)

SLNB is typically recommended for people with melanoma who have a 10% or greater risk of having spread of melanoma to the lymph nodes (pT1b or above). There are risk calculators that may be helpful to determine how likely spread of the disease is.

SLNB is typically performed under general anaesthetic and is a short operation. Local anaesthetic is injected at the time of surgery for maximum comfort post-procedure. After the operation, there may be some discomfort or tenderness around the incision site, which can be managed with over the counter pain medications, and occasionally prescribed medications.

At your first appointment, your diagnosis of melanoma will be reviewed in addition to your medical history. An examination of the melanoma site and lymph nodes will be performed. The procedure will be explained in detail, including the risks, benefits, and the potential outcomes. This is also the time for you to ask any questions you might have.

The operation typically takes 30 to 60 minutes. This includes the time for injection of the blue dye, local anaesthetic, and lymph node(s) removal. The SPECT-CT imaging is prior to the surgery and typically performed on the same day, or occasionally the day before.

The results of the lymph node biopsy will typically be available within 2 weeks. If the SLNB is negative for melanoma, the risk of further issues is lower. If the SLNB is positive for melanoma, the volume and location of melanoma will be reviewed. It may be that monitoring is the preferred option. For some patients, further oncology treatment will be recommended in the form of immunotherapy or targeted therapy.

While SLNB is generally safe, there are some risks and potential complications. The commonest risk is a fluid collection (seroma or lymphocele), which is typically drained in clinic. This is also associated with a risk of delayed wound healing. Other risks include infection, bleeding, scar and numbness.