Studies on intranuclear inclusions and nuclear grooves in papillary thyroid cancer by light, scanning electron and transmission electron microscopy.
OBJECTIVE
To successively examine intranuclear inclusions and nuclear grooves in the same papillary thyroid cancer specimens using a light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM).


METHODS
We stained cells by the Papanicolaou method after fixation in 1.25% glutaraldehyde for LM and then attempted to observe them successively by SEM-TEM after fixation in 2% paraformaldehyde and 2% osmium tetroxide.


RESULTS
On SEM, intranuclear inclusions were observed as elevated parts, like hills, and nuclear grooves were observed as deep fissures or shallow cracks, sometimes with a few in one cell. On TEM, both intranuclear inclusions and nuclear grooves seemed formed by the nuclear membranes. Intranuclear inclusions also possessed cytoplasm and/or cytoplasmic organelles within some expanded areas in the nuclear grooves.


CONCLUSIONS
It was evident from our three-step technique that intranuclear inclusions and nuclear grooves were essentially the same structures.
Kaneko
C
C
Institute for Comprehensive Medical Science, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
Shamoto
M
M
Niimi
H
H
Osada
A
A
Shimizu
M
M
Shinzato
M
M
D001707:Biopsy, Needle; D002291:Carcinoma, Papillary / Q000473:pathology* / Q000648:ultrastructure; D002467:Cell Nucleus / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D002479:Inclusion Bodies / Q000473:pathology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D013194:Staining and Labeling; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000648:ultrastructure