I had an MM a few years ago, clear now. Keep positive, keep smiling, you'll beat it.
Since the MM I continue to sail, observing the same sensible precautions recommended for anyone.
My MM was most likely caused by the irregular, prolonged sun exposure resulting in blistering that I experienced as a child. Subsequent non-blistering, non-burning exposure during my years of sailing full time in the tropics probably added little to the mix. White collar workers get more MM's than outside workers, it seems.
Anyway, there is sailing after MM, just take normal precautions. Best wishes for a full recovery.