We consider the semilinear elliptic problem −∆u = |u| p−1 u in B u = 0 on ∂B (Ep) where B is the unit ball of R 2 centered at the origin and p ∈ (1, +∞). We prove the existence of non-radial sign-changing solutions to (Ep) which are quasi-radial, namely solutions whose nodal line is the union of a finite number of disjoint simple closed curves, which are the boundary of nested domains contained in B.In particular the nodal line of these solutions doesn't touch ∂B.The result is obtained with two different approaches: via nonradial bifurcation from the least energy sign-changing radial solution up of (Ep) at certain values of p and by investigating the qualitative properties, for p large, of the least energy nodal solutions in spaces of functions invariant by the action of the dihedral group generated by the reflection with respect to the x-axis and the rotation about the origin of angle 2π k for suitable integers k. We also prove that for certain integers k the least energy nodal solutions in these spaces of symmetric functions are instead radial, showing in particular a breaking of symmetry phenomenon in dependence on the exponent p.