  Fusion - fission probabilities in the synthesis of heaviest elements are
discussed in the context of the latest experimental reports. Cross sections for
superheavy nuclei are evaluated using "Fusion by Diffusion" (FBD) model.
Predictive power of this approach is shown for experimentally known Lv, Og
isotopes and predictions given for Z=119,120. Ground state and saddle point
properties as: masses, shell corrections, pairing energies and deformations
necessary for cross section estimations are calculated systematically within
the multidimensional microscopic - macroscopic method based on the deformed
Woods-Saxon single particle potential. In the frame of FBD approach predictions
for production of elements heavier than Z = 118 are not too optimistic. For
this reason, and because of high instability of superheavy nuclei, we comment
on some structure effects, connected with the K-isomerism phenomenon which
could lead to a significant increase in the stability of these systems.
