My mum has had a stage 2c skin cancer removed /should she have the Sentinel lymph node biopsy for melanoma skin cancer

My mum had stage 2c melanoma removed from her forearm.
Going through the information given at the start the Sentinel lymph node biopsy for melanoma skin cancer appeared the norm to do next to rules spreading of cancer. The surgeon gave my mum choice to have this or not . It was my thought to have though I can’t help thinking with the way he made it come across that he was against it being done albeit stated it my mums choice  

my mum is 77 . She had the ct and mri scan to see if elsewhere so just doesn’t make sense to me that not doing the test would not be beneficial 

appreciate any advice please 

  • Hi I was first diagnosed with stage 2a last year then I had slnb and unfortunately I had 3 lymph nodes out of 6  contained micro melanoma. It is cured for now. So it is beneficial to have it done otherwise it could spread if any I  lymph  nodes.

  • Hi I’m  I’ve had melanoma cancer had my op and sentinel node biopsy  which they removed mistakes over diagnosis of nodes was told they was clear only to be told now they wasn’t they was traces of cancer there did you have any more checks after nodes were removed I’ve had nothing