The main issue with accutane isn't liver toxicity, but the main issue is triglyceride elevation and lipid profile skewing.
Both times I used accutane my bloodwork showed these issues after 4 months or so. Liver enzymes were never an issue.
So, the main reason you don't want to cycle while using accutane, is because AAS can also skew lipid profiles in a negative way.
You need to really watch your diet and bad fat intake.
Also, you need to use accutane for at least 4 months or so. It works slowly by shrinking the subQ glands that secrete sebum, an oily substance that is used to lubricate a hair follicle. Using it for a month or two is pretty much useless and you can count on having to use it again.