  In this contribution the role of quantum fluctuations for the QCD phase
diagram is discussed. This concerns in particular the importance of the matter
back-reaction to the gluonic sector. The impact of these fluctuations on the
location of the confinement/deconfinement and the chiral transition lines as
well as their interrelation are investigated. Consequences of our findings for
the size of a possible quarkyonic phase and location of a critical endpoint in
the phase diagram are drawn.
