240 THE LARYNX, BRONCHI AND OESOPHAGUS
in which most tumours start, is also within the neck area. These masses are
commonest in middle-aged patients and are more fully discussed on p. 140.
Any diffuse swelling of these glands is probably not neoplastic but is much
more likely to be due to parotitis (mumps), or sialectasis with or without
calculus formation. This latter condition is to the salivary glands what
bronchiectasis is to the lungs, and the contrast radiographic findings are very
similar with duct stenosis and stricture, saccular and cystic spaces, and a loss
of efficient functioning.
In the latter part of the nineteenth century Mickulicz described a syndrome
consisting of swelling of all four salivary glands and of the lacrimal glands.
This syndrome was later associated with keratoconjunctivitis and arthritis
(Sjogrerfs syndrome), sarcoidosis and uveitis (Heerfordt''s syndrome) and a dry
mouth, dry eye complex (Sicca syndrome). This pot-pourri has been shown
not to have many of the characteristics of auto-immune disease and is now
called benign lympho-epithelial lesion.
Other causes of diffuse enlargement of the salivary glands include diabetes,
iodides, gout, thiouracil, obesity, fibrous replacement, myxoedema and Cushing's
disease. Parotid swelling can be mimicked by masseteric hypertrophy, parasitic
cysts and branchial cysts.
The commonest benign tumour of salivary glands is a pleomorphic adenoma
which in the parotid usually presents near the lobe of the ear. Monomorphic
adenomas (Warthin's tumour) are usually bilateral and are cystic. The
commonest malignant tumours are adenoid cystic carcinoma and muco-
epidermoid carcinoma. The former invades nerves and often presents with
associated nerve palsies.
5. Congenital Swellings. Cystic hygroma is probably the rarest of all neck
swellings. It is obvious at birth and is due to a maldevelopment of the lymph
spaces into lymph trunks on one side of the cervicofacial region. It often
weighs nearly as much as the baby, is brilliantly transilluminable and can
rarely be mistaken for anything else.
Dermoids can occur anywhere along lines of fusion, and in the neck they are
almost invariably found above the hyoid bone in close relation to the mylo-
hyoid muscle. They are midline swellings which move on swallowing and on
protruding the tongue because they are ultimately related to the muscle
fibres forming the base of the tongue.
The commonest congenital mass occurring in the midline below the hyoid
bone is the thyroglossalduct cyst (Fig. 123). The thyroid forms high in the neck
at the base of the tongue and hyoid bone, and, as growth proceeds and the
neck grows, it descends to the lower part of the neck. If it retains its attach-
ment^to the tongue it is called a thyroglossal duct and any cystic space in this
duct is a thyroglossal duct cyst. The duct always joins the base of the tongue
by passing behind the hyoid bone, and thus thyroglossal duct cysts are always
found below the hyoid bone in the midline or occasionally just to the left of
the midline. The cyst moves on swallowing because it is attached to the
thyroid gland and also on protruding the tongue because of its attachment to
The commonest congenital lateral neck mass is the branchial cyst (Fig. 124).
This occurs anywhere along the line of the sternomastoid muscle and re-
presents the failure of disappearance of part of the branchial cleft apparatus.
The most usual site is at the junction of the upper third and lower two-thirds