Saturn MC and 10th house indicate ambition.
Transiting Pluto has been and will be in Capricorn for quite a while (several years). This Pluto transit means destruction and re-birth of the house it touches. In your case, it means a new opportunity to change career. Whatever decisions you make now will have powerful, long-term effects.
Also, if outside circumstances ask you to change jobs etc, don't be scared. Any change will be fated to happen = for the better.