We construct multiloop superparticle amplitudes in eleven dimensions
(11d) using the pure spinor formalism, which we compare with the multiloop
pure spinor superstring amplitudes prescription given by Berkovits.
We then argue that this construction points to some evidence for the existence
of a topological M-theory based on a relation between the ghost
number of the full-fledged supersymmetric critical models and the dimension
of the spacetime for topological models. In particular, we show that the extensions at higher orders of
the previous results for the tree and one-loop level expansion for the superparticle in 11 dimensions is
related to a topological model in 7 dimensions.