So you know


Why, what has been decided to retire voluntarily?

Tanaka : Suffering from incurable diseases and Tanaka fact, there also aspects physical condition, I was allowed to make a decision this time. So it does not bother to go to our players and staff, and I have to put a buttoned at the timing is not somewhere I had expected. Sometimes it is you want to go back to development as a creator of one site, and asked to retire also.
http://www.famitsu.com/news/201206/24016883.html

He been looking sick for years so it could be true he have a incurable diseases.