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Features Departments Information |
 ANNETTE WAGNER, MD
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Dermatology quiz ANNETTE WAGNER, MD aFall 2000  FIGURE 1 Appearance of scalp lesion at 3 months. A 4-YEAR-OLD FEMALE infant is referred for evaluation of an area of alopecia on the scalp. The mother reports that the area was present from birth. It was noted to be more erythematous for the first several months of life. Subsequently, the erythema resolved but the wart-like appearance and alopecia persisted. Recently, a brown area developed on one edge. There is no associated pruritus. No similar lesions are present elsewhere on the body. The infant was born by normal spontaneous vaginal delivery. An internal scalp monitor was placed to monitor decelerations noted with contractions. Apgars were 9 and 9. The baby was discharged home at 36 hours without complications. Pregnancy and past medical history are unremarkable. Development is normal.  FIGURE 2 Appearance of scalp lesion at 4 years. Note brown papule not present in infancy. The most appropriate next step is:
The most appropriate therapy includes:
The most likely diagnosis is:
Answers: D, B and B, respectively. Nevus sebaceous of Jadassohn is a hamartoma of normal elements of the skin with a preponderance of sebaceous glands. It is a well circumscribed hairless plaque that is usually solitary. Lesions are sporadic and occur in equal frequency in males and females in all races. Typical lesions are round, oval or linear, measuring from 5 mm to several centimeters in diameter, although much larger lesions can occur. The most common location for nevus sebaceous is on the scalp and face. Typical lesions of nevus sebaceous are faintly notable to erythematous inflammed papules and plaques with alopecia present at birth or noted early in life. Lesions are responsive to maternal hormone stimulation accounting for the inflammation which usually resolves over several months. Many parents do not seek medical attention for this birthmark because the improvement noted early in life suggests that the birthmark will spontaneously involute. Despite this, lesions are persistent and develop into a yellow brown or orange pink flat velvety plaque. The alopecia is also persistent. Lesions enlarge over time, growing with the patient. At puberty the hormones that stimulate pubertal changes result in thickening, erythema and nodularity in these lesions, similar to that noted a birth. Papillomatous or wart-like projections are also quite common beginning at puberty. The medical importance of a solitary nevus sebaceous relates to the description of neoplastic change in 10 to 15% of lesions in some series, although recent series suggest this number may be far lower.[2] These neoplasms generally occur during adolescence or adult life. Rarely, changes have occurred in children under five years of age.[3] The most common malignant neoplasm arising in this disorder is basal cell carcinoma. Trichoblastoma is the most common benign neoplasm.[4] Other benign and malignant tumors are also noted including syringocystadenoma papilliferum (a benign tumor arising from the apocrine sweat glands), keratoacanthomas, aprocine cystadenomas, leiomyomas, and sebaceous cell carcinoma.[5] Malignant eccrine poromas and aprocine carcinomas have been reported to result in wide spread metastasis and death.[1] The development of a rapidly enlarging papule within nevus sebaceous or of ulceration within the plaque may portend malignant degeneration. Appearance of these changes warrants immediate biopsy. Unfortunately, onset of malignancy can be insidious in these lesions and clinical recognition of a slow growing carcinoma within nevus sebaceous in adolescents and adults can be difficult. Moreover, the nodularity and wart-like appearance is undesirable for most teenagers. For these reasons, prophylactic excision of nevus sebaceous is recommended. The timing for excision of nevus sebaceous can safely be postponed in many children until the pre-adolescent years when it can be accomplished as a local procedure. However, if lesions measure more than one to two centimeters on the scalp it is recommended that excision be accomplished in infancy to allow for improved cosmesis in the closure. The differential diagnosis of nevus sebaceous includes juvenile xanthogranuloma, a benign tumor that appears in early infancy comprised of xanthomatous cells. Like nevus sebaceous, juvenile xanthogranulomas (JXGs) are often yellow. Unlike nevus sebaceous, however, JXGs tend to appear after birth and are more commonly dome-shaped rather than flat-topped with a verrucous surface. Solitary mastocytomas can also have an appearance similar to nevus sebaceous. Mastocytomas are comprised of a benign collection of mast cells within the skin; differentiation is possible in many lesions by stroking the skin. The mast cells contained in solitary mastocytomas release histamine into the skin producing an erythematous wheal that is known as Darier’s sign. Positive Darier’s sign is not seen in nevus sebaceous. Aplasia cutis congenita is another birthmark presenting as alopecia on the scalp. In this condition there is a localized absence of the development of skin. Babies are often born with an erosion that crusts and heals over several months as an atrophic or hypertrophic scar that is hairless. Other congenital malformations of the scalp include encephaloceles or dermoid cysts, which can have intracranial connections. In general, these are more irregular in shape, skin colored, non-yellow, and less flat surfaced and verrucous. On rare occasions, infants may present with a more extensive form of nevus sebaceous termed the nevus sebaceous syndrome (Schimmel Pennin’s syndrome). Larger lesions of nevus sebaceous are usually present on the scalp and face in association with major ophthalmic abnormalities, ocular dermoids, pigmentary and skeletal abnormalities, intracranial AV malformations, seizures, and even mental retardation. This syndrome probably occurs by mosaicism where in a lethal malformation syndrome survives by existing in the mosaic state. The prognosis for infants with this syndrome is poor; most die in early infancy. Recognition of lesions of nevus sebaceous because of their neoplastic potential is important for the general pediatrician. Parents should be educated in changes of concern and patients should be referred for excision prior to puberty. REFERENCES 1. Hurwitz S: Clin Pediatr Dermatol, 2nd edition., Philadelphia: WB Saunders Company Rheum Dis Clin North Am 1993:223–224. 2. Cribier B, Scrivener Y, Grosshans E: Tumors arising in nevus sebaceus: A study of 596 cases. J Am Acad Dermatol 2000;42:263–268. 3. LeSueur BS, Silvis NG, Hansen RC: Basal cell carcinoma in children: Report of 3 cases. Arch Dermatol 2000;136:370–372. 4. Jaqueti G, Requena L, Sanchez Yus E: Trichobastoma is the most common neoplasm developed in nevus sebaceus of Jadassohn: A clinicopathologic study of a series of 155 cases. Am J Dermatopath 2000;22:108–118. 5. Yoon DH, Jang IG, Kim TY, Kim HO, Kim CW: Syringocystadenoma papilliferum, basal cell carcinoma and trichilemmoma arising from nevus sebaceus of Jadassohn [letter]. Acta Dermato-Venereologica 1997;77:242–243. |