There's no way to build "lean mass" as Gaz stated. The best you can hope for is to build mass and eat the right foods so that you do not increase your BF too much.
This guy clearly wants to cut. Sure, keeping mass is a goal, but adding mass isn't really possible if you're in a caloric deficit. If you want to cut, do enough cardio (I wouldn't say 5 days a week is too much), put yourself in a small caloric deficit (don't overdo it), and lift at maintenence. You're going to lose some mass and strength along with it, that's just the nature of cutting.
But I disagree that "cardio is just cardio". I guess it depends on what your training goals are, but I think different cardio forms are much different (then again I am more of an endurance athlete than a bodybuilder). If you're training for bodybuilding, it doesn't make much difference what cardio you do as long as you can work in HIIT and burn calories.
I actually believe cutting is 90% about your diet. Sure, cardio will help you burn that last extra BF, but dieting correctly will help you get to the point where you need more cardio. When cutting, worry more about your diet than any form of cardio you're going to do.