Chapter 16. External Angular Dermoid and Pilomatrixoma 169
16.3 Indications for Referral
Presence of a swelling under the lateral end of the eyebrow with or without an opening.
16.4 Pilomatrixoma (Calcifying Epithelioma
of Malhebre)
16.4.1 Introduction
This is a rare lesion, occurring in middle aged men, in a hair bearing area (usually the front of the trunk). It presents as a painless slowly enlarging subcutaneous nodule, mobile and non tender. Average size of the lesion is 0.5–1 cm in diameter. With larger lesions thinning of the overlying skin may occur. The tumor is hard and may feel gritty.
Treatment of the Pilomatrixoma is excision, usually accomplished under local anesthesia. The tumor is easily removed in its entirety.
Pathological examination shows large pale cells resembling epidermal keratinocytes and empty “shadow” cells devoid of nuclei. There is a fibrocollagenous stroma with multinucleated giant cells and small areas of calcium deposition.
Recurrence of a pilomatrixoma is uncommon. Indications for Referral – presence of a hard mobile non
tender subcutaneous nodule.
Suggested Reading
1.Smith CD. Cysts and sinuses of the neck. In: Grosfeld JL, O’Neill JA, Fonkalsrud EW, Coran AG, eds. Pediatric Surgery. 6th ed. St. Louis, MO: Mosby Elsevier; 2006:861-874.
Chapter 17
Neck Swellings/Lumps:
Midline Neck Swellings
Neil Bateman
Key Points
››Thryoglossal duct cysts are the commonest congential abnormality in the neck. They can usually be easily diagnosed clinically.
››The diagnosis of a thyroglossal duct cyst can be confirmed, and the presence of normal thyroid can established, be ultrasound.
››A midline block excision of tissue from the level of the thyroid up to the tongue base, including the middle third of the hyoid bone is the treatment of choice in thyroglossal duct cysts.
››Dermoid cysts can be distinguished from thyroglossal duct cysts by their failure to move on tongue protrusion.
››Dermoid cysts can be easily treated by simple surgical excision. If there is any doubt over the diagnosis then the lesion should be treated as a thyroglossal cyst.
P.P. Godbole et al. (eds.), Guide to Pediatric Urology and |
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Surgery in Clinical Practice, DOI: 10.1007/978-1-84996-366-4_17,
© Springer-Verlag London Limited 2011
172 Neil Bateman
17.1 Introduction
Neck lumps occurring in children can be usefully divided into those occurring in the midline of the neck, discussed here, and those situated laterally. While it is very uncommon for midline neck lumps represent sinister pathology it is very important that these lesions are accurately diagnosed and treated by those with a specialist interest as the treatment of those children receiving initial inappropriate treatment can be very challenging.
17.2 Differential Diagnosis
of Midline Neck Lump
17.2.1 Thryoglossal Duct Cyst
This is a developmental abnormality and represents the commonest congenital abnormality in the head and neck.The thyroglossal duct is formed by the descent of the thyroid gland in the fetus from the foramen cecum in the tongue base to its familiar position anteriorly in the neck. Under normal circumstances the duct involutes between the 8th and 10th week of gestation. Cysts forming in a persistent duct are clinically known as thyroglossal duct cysts. The thyroglossal duct is closely related to the hyoid bone. This gives rise to the cardinal clinical sign of these lesions, namely elevation on tongue protrusion.
Thyorglossal duct cysts can present at any age although it is very rare for them to be present at birth. They are almost all in the midline (Fig. 17.1) although they can occur more laterally in the neck. When this happens, it is more commonly on the left. Recurrent episodes of infection may occur and, if sufficiently severe and frequent, this may lead to cyst rupture and subsequent sinus formation.
It is theoretically possible, although very rare, that a lesion with the appearance of a thryoglossal duct cyst is, in fact, an incompletely descended thyroid gland. Under these circumstances it is possible that the lesion represents the only viable thyroid tissue. There are some case reports of thyroid carcinoma occurring in these lesions.