Does Cryofixation of Skin Specimens Affect Quality of Subsequent Formalin Fixed Paraffin Embedded H and E Histology

Generating formalin fixed paraffin embedded (FFPE) hematoxylin and eosin (H&E) stained
permanent sections from previously cryofixed tissue is a common practice used to confirm
diagnosis of frozen section histology. In dermatology, this practice can be used to examine
Mohs layers and its debulk as well as routine nonmelanoma skin cancer (NMSC) biopsies after
initial histologic diagnosis with frozen sections. Even though freezing tissue can introduce
histologic artifacts, there have been no studies documenting whether this occurs
specifically in cryofixed tissues that are subsequently thawed for permanent FFPE H&E
histology. The purpose of our study is to determine whether the freeze-thaw process used to
generate permanent sections after cryofixation introduces significantly detectable
histologic differences compared to permanent sections that were not previously cryofixed.
Thirty debulk specimens of basal cell and squamous cell carcinomas will be prospectively
collected. Each specimen will be split so that half is processed as cryofixed permanents and
the other half as noncryofixed permanents. The investigator will show each slide in random
order to a group of four blinded participants (two dermatopathologists and two Mohs
surgeons). Each participant must first rate the overall quality of histology. Then, each
participant will rate each slide on the quality of cellular morphology, nuclear morphology,
color and contrast of stains, intactness of specimen, and other miscellaneous artifacts.
These data will then be analyzed for statistical significance.

Inclusion Criteria:

- Adult patients (age 18 or over) with a biopsy proven routine basal cell or squamous
cell carcinoma of the skin who are scheduled for treatment with the Mohs procedure by
Dr. Christopher Miller at the University of Pennsylvania's Division of Dermatologic
Surgery will be included. Both female and male patients will be included.

Exclusion Criteria:

- Patients with basal cell or squamous cell carcinomas of more complex histopathology
will be excluded from the study. Complex histopathology of a tumor is defined as
features with aggressive, moderately to poorly differentiated, or unusual
histopathology.