May 1, 1997
Electron Microscopy of Paraffin Embedded
Tissue
T. Wallace, M.D., N. Grossl, M.D., V. Murrah, DDS; S.
Muller, DDS.
Department of Pathology
Emory University School of Medicine
Atlanta, GA.
Katherine Chorneyko, M.D.
Department of Pathology
McMaster University Medical Center
Hamilton, Ontario
A basic tenet of diagnostic electron microscopy is that rapid
tissue fixation in a glutaraldehyde based fixative is necessary
for the optimal preservation of ultrastructural organelles. But
what if, electron microscopy is needed for either initial
diagnosis or the confirmation of a light microscopic diagnosis
and the only tissue available is formalin fixed (10% neutral
buffered formalin), paraffin embedded material. Can electron
microscopy be performed on paraffin embedded tissues and will
diagnostic organelles be recognizable? The following case
presentations illustrate the usefulness of paraffin embedded
material for electron microscopy.
Materials and Methods
For each case, the tissue for light microscopy was fixed in
10% neutral buffered formalin and embedded in paraffin. Three
micron sections were prepared from the paraffin blocks and
stained with hematoxylin and eosin. For cases one and three,
additional tissue sections were prepared for immunohistochemical
staining with the antibody to S-100 protein using the
avidin-biotin technique.
All cases had representative tissue retrieved from the
paraffin block, deparffinized and reprocessed for electron
microscopy. Only case two had fresh tissue that was submitted in
a glutaraldehyde based fixative for electron microscopy.
Case Presentations
Case 1
Clinical History
A forty year old female presented with a history of facial
trauma. Physical examination demonstrated hypesthesia in the
region of the left mental nerve. She also had mobile teeth in
the region of the left mandible as well as poor oral hygiene.
Panorex radiographs of the oral region demonstrated a
fracture of the body of the left mandible. The fracture was
associated with an expansile, lytic lesion in the body of the
mandible. Chest radiographs were unremarkable.
Following an initial biopsy of lytic lesion in the
mandible, the lesion was curetted and all teeth that were
associated with the mandibular lesion were extracted.
Additional radiographs of the skull were obtained and these
radiographs demonstrated multiple, radiolucent areas in the
calvarium.
Case 2.
Clinical History
A six year old, who had been previously treated for
a medulloblastoma/PNET (Peripheral Neuroectodermal Tumor) one
year earlier, developed a lytic lesion in the left iliac
crest. A biopsy was performed and portions of the biopsy were
submitted for electron microscopy.
Case 3.
Clinical History
A thirty eight year old female presented for
surgical treatment of left sided chronic mastoiditis that had
been present for a year. Six months later, she was again seen
for the treatment of chronic mastoiditis on the opposite
side. A biopsy was performed.
The patient's past medical history was significant for the
diagnoses of diabetes insipidus and secondary amenorrhoea one
year ago.
Retrospective review of radiographs of the mastoid regions
demonstrated bilateral, punched out radiolucencies in the
region of the mastoid air cells. Additional radiographic
studies also demonstrated lesions in the pituitary and lungs.
Send your online comments
or questions to the webmasters.
Society for
Ultrastructural Pathology
© Society for Ultrastructural Pathology
All Rights Reserved
Page design and webhosting provided by Ultrakohl
