Historically, in 2009 I had a Stage 1 0.3mm Malignant Melanoma removed from my right leg, followed by a Wide Local Excision (WLE).  No recurrence of Melanoma until now.

I have recently been diagnosed with a Stage 1B 1.3mm Malignant Melanoma on my upper left back and am currently scheduled to have a further WLE and Sentinel Lymph Node Biopsy (SNB).

During my post diagnosis review with the specialist Doctor, I understood that the SNB is a diagnostic procedure and optional.  I did ask at the time what the outcomes and treatments would be if deciding or not to have the SNB, but understandably the Doctor explained the various factors were too complex to provide a relevant answer.

Following the review with the Doctor, a nurse followed up and checked I had understood what had been discussed, and gave me a leaflet on SNB.

Following that, I read the leaflet, that confirmed the SNB was a diagnostic procedure which facilitates improved staging, but stated that SNB ‘has no proven survival benefit’.  I have followed up on this statement with the Cancer nurses, and had a telephone conversation with the Doctor who undertook the diagnosis review.  I ask, as all surgery has risk, why undertake a SNB which 'has no proven survival benefit'.  I have not had an answer which makes sense to me, and I continue to be advised that the SNB is optional.

What I am trying to understand is, based on experience, out of say 100 Stage 1B patients who undertake SNB, what is the 5 year survival rate compared with a separate 100 Stage 1B patients who choose not to have the SNB?  If I understand the statement 'has no proven survival benefit' correctly, there is no difference in 5 year survival rate.  My logic therefore is to not take any risk (even if small) with the SNB.

Is my logic or understanding faulty?