Salivary Glands and Rare Head and Neck Lesions
Fig. 22.3 Normal salivary gland. Aspirate. (A) Cohesive ball-like formations constituted by acinar cells and a group of ductal cells (May-Grunwald-Giemsa
x HP). (B) Groups of acinar cells with abundant granular and well-demarcated cytoplasm. The nuclei are round and centrally located (Papanicolaou x HP).
An aspirate from a benign retention cyst is usually clear and has a
watery to viscous consistency. It can, however, be cloudy and yel-
lowish when secondary inflammation has taken place. The smear
usually contains only a few histiocytes and degenerative epithe-
lial cells. Epithelial cells of cuboidal, columnar, or squamous type
can be found together with inflammatory cells and histocytes.
If the palpatory findings normalize after aspiration and the
smear contains only a few phagocytes or occasional epithelial
cells, the lesion is probably a retention cyst.
Key features of non-neoplastic cysts
Water-like or viscous mucoid aspirate;
Histiocytes and other inflammatory cells; and
Epithelial cells—cuboidal and squamoid.
Sialoadenosis is a benign, noninflammatory, non-neoplastic
enlargement of one or both parotid glands. The cause of sialo-
adenosis is unknown but may be associated with diabetes, liver
cirrhosis, or nutritional and hormonal disturbances.18
FNA demonstrates cellular smears of normal or slightly enlarged
Nodular oncocytic Hyperplasia
Nodular oncocytic hyperplasia refers to a condition with more
than one nodule, whereas oncocytoma refers to a single neo-
plasm. The distinction between the two may at times be arbi-
trary. Nodular oncocytic hyperplasia is often combined with
significant clear cell change, which may create a similarity to
acinic cell carcinoma.19-22
Aspirates contain cohesive clusters of cells showing a transi-
tion between oncocytes and acinic cells, with abundant finely
vacuolated or finely granular cytoplasm. Cells from an acinic
cell carcinoma tend to have more prominent nucleoli and
occasionally also a red granulation (May-Grunwald-Giemsa) of
cytoplasm. The cell patterns, however, can in extreme cases over-
lap to a certain extent but should in a majority of cases cause no
In young individuals, viral infections have a predilection for
involving the parotid glands, which become diffusely enlarged.
The diagnosis is usually obvious on clinical grounds and rarely
requires morphologic confirmation.
Acute bacterial sialoadenitis is characterized by diffuse painful
enlargement of the salivary gland. It occurs with equal frequency
in the parotid and submandibular salivary glands, mostly in
elderly patients. Poor oral hygiene with dehydration, sialolithi-
asis, and impaired immune response are generally thought to
be immediate or contributory causes of this condition. Acute
sialoadenitis with or without abscess formation can clinically
simulate a malignant tumor.
Aspirates from acute inflammatory salivary gland lesions
contain fibrin, cellular debris, neutrophils, lymphocytes, and
histiocytes (Fig. 22.4). In cases with sialolithiasis, calculi may
also be encountered.
Key features of acute bacterial sialodenitis
• Debris, fibrin;
• Neutrophils, macrophages, histiocytes; and
• Epithelial cells of both acinar and ductal type.
Nonspecific chronic sialoadenitis is often secondary to stricture
and obstruction of the ducts. In elderly patients, decreased secre-
tion of saliva and retrograde infections may result in a gradual
diffuse enlargement of the salivary glands. It is frequently seen
after radiotherapy of the oral cavity. Symptoms include recur-
rent mild pain and diffuse swelling related to eating. In more
chronic cases of sialoadenitis, the gland becomes fibrotic and
hard, with secondary atrophy of acini and proliferation of
ductal epithelium. In obstructive sialoadenitis caused by calculi,