This is a review of the fine-needle aspirates (FNAs) of nine pilomatri
xomas (PMs)found in a series of 1,500 FNAs performed on skin nodules.
The objective is to determine and list the cytologic findings that mig
ht mislead the less-experienced cytopathologist and to give him advice
on how to avoid such errors. The following recommendations are made:
1) The FNAs should be carried out and the smears interpreted by the sa
me person. 2) Clinical data, particularly age and location, are of par
amount importance. 3) Shadow cells are pathognomonic of PMs. 4) Basalo
id nuclei with prominent nucleoli should not be overdiagnosed. 5) Use
both Papanicolaou and Diff-Quik stains. 6) Think of PM when performing
and interpreting aspirations from subcutaneous growths located in the
head and neck of young persons. (C) 1996 Wiley-Liss, Inc.