JWM,
50% was absorbed in the study you are refering to. They wiped the skin with cotton swabs after 6 hours and got 50% off the scalp. Yes, metabolites of 16% was found in urine. The rest was unaccounted for, probably bonded to androgen receptors all over the body, or maybe stuck in some fat.
Every study on flutamide that measured its affects in more than one area has found it has an equal effect at the point of application as it does at the far away other point they measured where it was not applied. What does that say about its effects on the rest of the body? If you want to take 2.5mg of Avodart a day, but don't have the money and don't want the extra DHT, then cut up a flutamide pill and gradually take higher oral doses to see what you can handle. It is the poor man's dutasteride. But beware of possible side effects. I would NOT do that myself.