From NCS:
"New PC-Engine Game Confirmed
Dead of the Brain 1&2 for the PC Engine will be released
on June 3 and it will represent the last game for the
Engine. However, NCS will be unable to supply this game
to retail customers in the USA. NEC Home
Electronics is only producing a limited quantity of DOB
and they will limit distribution of the game to two retail
chains in Japan. In cases like this, we would usually try to
hand carry the game from retail to our distribution in the
USA but supplies are so scarce that even if we do try to
procure this title, we would be severely limited in the
numbers that we'd be able to import. We will evaluate the
situation further but as of today, we have no plans to
import this game due to it's extremely limited nature."