Page 537 - Textbook of Pathology, 6th Edition

or 3rd branchial clefts. The cyst is generally located anterior bifurcation of the common carotid arteries. Carotid bodies 521
to the sternocleidomastoid muscle near the angle of the are normally part of the chemoreceptor system and the cells
mandible. The cyst is 1-3 cm in diameter and is filled with of this system are sensitive to changes in the pH and arterial
serous or mucoid material. oxygen tension and are also the storage site for catechola-
mines. Histologically similar tumours are found in other
Microscopically, the cyst is lined by stratified squamous parasympathetic ganglia represented by the vagus and
or respiratory epithelium, covering subepithelial glomus jugulare (jugulotympanic bodies, Chapter 27).
lymphoid tissue aggregates or follicles with germinal Carotid body paragangliomas, as they are currently called,
centres.
are rare tumours and occur between 3rd and 6th decades of
life with slight female preponderance. A few (5%) are bilateral
PARATHYROID CYST. Parathyroid cyst is a lateral cyst of and some show familial incidence.
the neck usually located deep to the sternocleidomastoid
muscle at the angle of the mandible. These may be Grossly, they are small, firm, dark tan, encapsulated
microscopic cysts or larger. They are generally thin-walled, nodules.
filled with clear watery fluid.
Microscopically, well-differentiated tumour cells form
Microscopically, parathyroid cyst is lined by flattened characteristic organoid or alveolar pattern, as is the case
cuboidal to low columnar epithelium and the cyst wall with all other neuroendocrine tumours. The tumour cells
may contain any type of parathyroid cells. contain dark neurosecretory granules containing
catecholamines.
CERVICAL THYMIC CYST. Cervical thymic cyst originates These tumours are mostly benign but recurrences are
from cystic degeneration of Hassall’s corpuscles. It is frequent; about 10% may metastasise widely.
generally located in the left lateral side of the neck.
TORTICOLLIS (FIBROMATOSIS COLLI, WRY NECK).
Microscopically, the cyst is lined by stratified squamous This is a deformity in which the head is bent to one side while
epithelium and the cyst wall may contain thymic the chin points to the other side. The deformity may occur as
structures. congenital torticollis or may be an acquired form. The acquired CHAPTER 18
form may occur secondary to fracture dislocation of the
CYSTIC HYGROMA. Cystic hygroma is a lateral swelling cervical spine, Pott’s disease of the cervical spine, scoliosis,
at the root of the neck, usually located behind the spasm of the muscles of neck, exposure to chill causing
sternocleidomastoid muscle. It may be present congenitally myositis, and contracture following burns or wound healing.
or may manifest in the first 2 years of life. It is usually The congenital or primary torticollis appears at birth or within
multilocular and may extend into the mediastinum and the first few weeks of life as a firm swelling in the lower
pectoral region. third of the sternocleidomastoid muscle. The etiology is
unknown but about half the cases are associated with breech
Microscopically, cystic hygroma is a diffuse lymphan- delivery.
gioma containing large cavernous spaces lined by
endothelium and containing lymph fluid (page 412). Grossly, the muscle is contracted, shortened and fibrous. The Eye, ENT and Neck
Microscopically, abundant dense fibrous tissue separates
TUMOURS the muscle fibres.
Tumours of the neck may be primary or metastatic in cervical MALIGNANT LYMPHOMAS. Various forms of non-
lymph nodes. Hodgkin’s lymphomas and Hodgkin’s disease occur in the
cervical lymph nodes which are described in Chapter 14.
Primary Tumours
Secondary Tumours
A few important examples of primary tumours in the neck
are carotid body tumour, torticollis and malignant Cervical lymph nodes are common site for metastases of a
lymphomas. large number of carcinomas. These include: squamous cell
carcinoma of the lips, mouth, tongue, larynx and oesophagus;
CAROTID BODY TUMOUR (CHEMODECTOMA, transitional cell carcinoma of the pharynx and nasopharynx;
CAROTID BODY PARAGANGLIOMA). Carotid body thoracic and abdominal cancers such as of the stomach, lungs,
tumour arises in the carotid bodies which are situated at the ovaries, uterus and testis.

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