I would try to break or cut out in frozen state as good as possible. For further clean-up, several answers for different needs already exist here.

https://www.researchgate.net/post/What_methods_exist_to_remove_Tissue-Tek_from_tissue_samples_meant_for_Mass_Spectrometry_Imaging

Hi Diane,

I made several time, normaly I  cut slice of OCT using surgical blades in dry ice, then defrizing at 4°C quickly and using RIPA buffer for protein extraction or tryzol for RNA.

  Good luck

Let me know if you had a good result. I am interested in doing this