Derek,
     I believe you might be cutting on the cold side for thyroid. If this
is frozen in liquid nitrogen, it will have to warm up to -12/-10 before you
can cut without the tissue shredding. At the warmer temperature your O.C.T.
will want to curl but your tissue should be OK. Give me a call if you have
further questions.
               Don Birgerson
               Applications Specialist
               Leica-Microsystems
               Technical Assistance Center
               1-800-248-0123  ext. 5918