PART TWO
Diagnostic Cytology
Fig. 22.39 Pilomatrixoma (calcifying epithelioma of Malherbe). Aspirate
contains tumor cells, multinucleated foreign-body giant cells, amorphous
calcium deposit, and sheets of shadow cells. The tumor cells, single or in
clusters, have round monotonous nuclei and poorly defined cytoplasm
(May-Grunwald-Giemsa x MP).
Meningioma
In rare cases, meningiomas may have an extracranial extension
and present as tumors in the head and neck region. We have
encountered such meningiomas in the deep lobe of the parotid
gland, the soft tissue of the forehead, parietal and retroauricular
regions, and orbital and nasal cavities.
Cytology
Smears of aspirates show cells with monotonous round or oval
nuclei and pale opaque blue (May-Grunwald-Giemsa) cyto-
plasm (Fig. 22.40). Bud-like structures with cells concentrically
arranged are frequent findings. Intranuclear inclusions and
psammoma bodies are also common features.
Key features of meningioma
Bud-like structures with concentrically arranged
cells;
Monomorphic cells with round/oval nuclei;
Intranuclear inclusions; and
Psammoma bodies.
Rhabdomyoma
Rhabdomyoma is a rare benign skeletal muscle tumor with a
predilection for the larynx, pharynx, and oral cavity. We have
reported one case of rhabdomyoma that presented as a well-
circumscribed cervical mass fixed to the larynx and have also diag-
nosed a case with growth in the tongue and floor of mouth.80
Cytology
FNA smears showed cells with abundant granular cytoplasm and
round monomorphic nuclei (Fig. 22.41). Many cells had two or
more nuclei. The cells were positive for desmin and myoglobin
but lacked immunoreactivity for smooth muscle actin and S-100
protein.
Key features of rhabdomyoma
Large cells with abundant bluish granular cytoplasm
and round nuclei; and
Multinucleated cells.
Fig. 22.40 Meningioma. Fine-needle aspiration smear shows cluster
of monotonous cells with round or oval nuclei and calcifications (May-
Grünwald-Giemsa x MP).
Fig. 22.41 Rhabdomyoma. Aspirate presents large, polygonal cells with
abundant, granulated cytoplasm, similar to normal striated muscle. The
nuclei are round and located at the periphery (May-Grunwald-Giemsa x MP).
Fibromatosis Colli
Fibromatosis of the sternocleidomastoid muscle is a relatively
rare lesion observed during the first months of life. A history of
birth trauma is common, but at present it is not known whether
the process is reparative or neoplastic. Fibromatosis colli presents
as a firm mass in the lower/middle part of the sternocleidomas-
toid muscle. The process is in most cases self-limiting and never
behaves aggressively. On clinical examination, it is a firm mass
that can be difficult to recognize and as a consequence may be
the target for FNA biopsy.
Cytology
The aspirates show slender spindle-shaped fibroblasts without
atypia. Degenerated striated muscle fibers, as well as stromal
collagen, are commonly found. Inflammatory cells are few.81
Key features of fibromatosis colli
Collagen fragments;
Mature fibroblasts; and
Degenerated, atrophic striated muscle fibers.
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