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C.S.J. DUNKIN, M. ABOUZEID and K. SARANGAPANI
Department of Plastic and Reconstructive Surgery, Middlesbrough General Hospital,
Middlesbrough, UK
Sebaceous naevi are uncommon congenital skin lesions with a well-recognised potential for neoplastic change. They should be considered premalignant lesions as malignant degeneration, most commonly basal cell carcinoma and squamous cell carcinoma, occurs with a lifetime risk of between 5% and 22%. This incidence is equal to that of actinic keratosis and exceeds that of oral leukoplakia. Such change, however, is rare before puberty. Basal cell carcinoma may develop in children with naevoid basal cell carcinoma syndrome, xeroderma pigmentosum and rarely de novo but sebaceous naevus is the only solitary lesion in childhood associated with the development of basal cell carcinoma. We present two cases of malignant transformation in a congenital sebaceous naevus occurring in childhood and review the literature and discuss the evidence upon which to base management guidelines.
Keywords: basal cell carcinoma, children, epidermal naevus syndrome, malignant degeneration, sebaceous naevus
J.R.Coll.Surg.Edinb., 46, October 2001, 303-306
Naevus sebaceous are uncommon hamartomatous lesions occurring in 0.3% of neonates.1 They were first described by Jadassohn in 1895 and are most commonly seen on the head and neck whilst similar lesions elsewhere on the body are termed verrucous epidermal naevi.2 Epidermal naevus syndrome is a well-described but poorly recognised syndrome characterised by extensive sebaceous naevi and developmental defects of the central nervous system, ocular and skeletal systems.3 Usually recognised at birth or in early childhood sebaceous naevi remain small and hairless until puberty when they may become larger and verrucous. In late adult life they have a well-documented neoplastic potential. Such changes are rarely seen in childhood. We describe two cases of the malignant transformation of a congenital sebaceous naevus occurring in childhood.
An 11-year-old girl was referred by her family doctor with a lesion on the right cheek that had been present since birth. In the preceding three months her mother had noticed a change in the lesion. On close inspection she had a linear lesion on the right cheek that measured 41 mm in length with a maximum width of 12 mm. This was a well-defined yellow, alopaecic plaque with a granular surface (Figure 1). In the centre of the lesion there was a 3 mm erythematous exophytic nodule with a second 1 mm nodule beside it (Figure 2). Past medical history and general physical examination were unremarkable.
Figures 1: An 11-year-old patient with a congenital sebaceous naevus on the right cheek with an exophytic nodule in the centre
Under general anaesthetic the lesion was excised as an ellipse with a 2 mm clearance margin and the wound closed primarily. Sections were stained with haemotoxylin and eosin and examined with a light microscope. Histology demonstrated a typical sebaceous naevus with abundant mature sebaceous glands and a moderate infiltration of lymphocytes and histiocytes (Figure 3). In the centre, fascicles of epithelial cells were seen in a lace-like pattern within a mucoid stroma forming tubular gland-like structures. Cells at the periphery of the tumour showed a palisade arrangement of nuclei characteristic of basal cell carcinoma (Figure 4). Complete excision of the lesion was reported.
Figure 2: Detail of congenital sebaceous naevus shown in Figure 1
Figure 3 Figure 4
Figure 3: Haematoxylin-eosin stain demonstrating typical sebaceous naevus with abundant mature sebaceous glands and a moderate infiltration of lymphocytes and histiocytes Figure 4: Centrally situated fascicles of epithelial cells in a lacelike pattern within a mucoid stroma are seen forming tubular gland-like structures. Cells at the periphery of the tumour show a palisade arrangement of nuclei typical of basal cell carcinoma
The second patient was also an 11-year-old girl referred by her dermatologist. She had a large congenital sebaceous naevus on the right side of the forehead in which she had noticed a change over the preceding month. On examination she had a lesion with the classical appearance of a sebaceous naevus measuring 67 x 29 mm with an irregular area (12 x 8 mm) just below the hairline. An incision biopsy, performed by the dermatologist, showed a sebaceous naevus with a focus of early morphoeic basal cell carcinoma. Under general anaesthetic we planned an elliptical excision of the lesion with a 2 mm margin. This was performed and the defect reconstructed primarily with a split-thickness skin graft (Figure 5). The specimen was stained with haematoxylin and eosin and examined with a light microscope.
Histopathology confirmed the biopsy findings identifying a sebaceous naevus with a focus of basal cell carcinoma. It also demonstrated another distinct tumour, a benign hidradenoma, developing within the same lesion. Tissue expansion reconstruction was proposed but at 12 years of age the patient declined and instead serial excision of the skin graft was performed over the next three years (Figure 6).
Figure 5: Reconstruction of the forehead defect with a splitthickness skin graft
Figure 6: The result after serial excision of the skin graft
Sebaceous naevi are uncommon hamartomatous lesions seen in 0.3% of neonates and 0.68% of skin biopsy specimens.1-4 Up to 95% occurs on the scalp and face.2,5
In 1965, Mehregan and Pinkus described the natural history of the lesion in three stages.5 In the infantile stage, the lesion presents as a characteristic quiescent yellow plaque. Histologically, there is a paucity of underdeveloped sebaceous glands and hair follicles. At the time of puberty, growth of the lesion is accelerated and it becomes verrucous. Light microscopy shows masses of hypertrophic sebaceous glands with papillomatosis and hyperkeratosis of the overlying epidermis. This is the second or pubertal stage.
The third or neoplastic stage sees the development of secondary tumours and usually occurs in late adult life. The clinical signs suggesting neoplastic transformation include rapid enlargement or the development of nodularity or ulceration. Several different tumours of epidermal, adnexal and mesenchymal origin are known to arise. Benign tumours are the most common including syringocystadenoma papilliferum, apocrine cystadenoma, trichoblastoma, trichilemmal cysts and keratoacanthoma. Occasionally, multiple tumours are observed within a pre-existing lesion.5 Malignant degeneration, although less common, occurs with a lifetime risk of between 5 and 20%. 6,7,8 The majority of these tumours are basal cell carcinomas but squamous cell, sebaceous and apocrine carcinomas are also recognised. Most are of low-grade malignancy but more aggressive histological features and metastases are occasionally seen. It has been suggested that these tumours may arise from pluripotential epithelial germ cells as a result of dedifferentiation of sebaceous naevus cells, the nature of the tumour depending upon the degree of subsequent differentiation.9
Some authorities consider sebaceous naevus to be a premalignant lesion and the incidence of malignant change is equal to that of actinic keratosis and exceeds that of oral leukoplakia.10
Basaloid cells in sebaceous naevus have been shown to share deletions with basaloid cells in basal cell carcinoma (at 9q22.3) in the human homologue of the Drosophila patched gene (PTCH) which may act as a tumour suppressor. 11
Basal cell carcinoma is a tumour associated with advancing years but may develop in children with naevoid basal cell carcinoma syndrome, xeroderma pigmentosum and rarely de novo. Sebaceous naevus is the only solitary lesion associated with the development of basal cell carcinoma in children.12
Malignant change in sebaceous naevus is most commonly seen in middle to late life with a median age in the seventh decade. 13 However, there are three reports in the English language literature of basal cell carcinoma developing in sebaceous naevus in children. All were under 10 years old whilst the youngest was just 5 years old. 7,10,14 There are two further reports of malignant transformation occurring in teenagers. 4,15 We describe two patients with congenital sebaceous naevi in which malignant transformation had occurred at 11 years of age.
There is little evidence in the literature upon which to base clinical guidelines on the management of sebaceous naevus, regarding either the age at which intervention should be planned or the best modality of treatment. The two main options are excision with primary reconstruction and histological examination around the time of puberty and the more conservative approach of excision if clinical signs of malignant transformation occur. An alternative is dermabrasion or dermablation with diathermy or laser but this does not provide tissue for histological examination and occult basal cell carcinoma has been found in lesions with no evidence of transformation either clinically or on incisional biopsy. 16 Mehregan and Pinkus go further and hypothesise that superficial destruction of the lesion may provoke cellular transformation.5
In light of the available evidence we advise that parents are informed of the diagnosis and counselled as to the neoplastic potential of the lesion and the rare occurrence of malignant change in childhood. We suggest complete excision of the lesion with histological examination and primary reconstruction before puberty.
1. Alper J, Holmes L. The Incidence and significance of birthmarks in a cohort of 4641
new-borns. Pediatr Dermatol 1983; 1:58-66
2. Rook A. Naevi and other developmental defects. In: Rook A, Ebling FJG, Wilkinson OS,
eds. Textbook of Dermatology, 4th ed. London: Blackwell Scientific Publications,
1986; 1: 174-6
3. Solomon L, Fretzin D, Dewald R. The epidermal naevus syndrome. Arch Dermatol 1968;
97: 273-85
4. Wilson-Jones E, Heyl T. Naevus sebaceous - a report of 140 cases. Br J Dermatol 1970;
82: 99-117
5. Mehregan A, Pinkus H. Life history of organised nevi. Arch Dermatol 1965; 91:
574-88
6. Chun K, Vazquez M, Sanchez JL. Naevus sebaceous: Clinical outcome and consideration for
prophylactic excision. Int J Dermatol 1995; 34: 538-41
7. Piansay-Soriano EF, Pineda VB et al. Basal cell carcinoma and infundibuloma
arising in separate sebaceous naevi in childhood. J Dermatol Surg Oncol 1989; 15:
1283-6
8. Sasson M, Mallory SB. Malignant primary skin tumours in children. Current Opinion in
Paediatrics 1996; 8: 372-7
9. Lever W, Schaumburg G. Tumours of the epidermal appendages. In: Lever W, Schaumburg G,
eds. Histopathology of the skin, 7th ed. Philadelphia: Lippincott, 1990: 594-6.
10. Constant E and Davis D. The premalignant nature sebaceous naevus of Jadassohn. Plast
Reconstr Surg 1972; 50: 257-9
11. Xin H, Matt D, Jian-Zhong Q, Burg G, Boni R. The sebaceous naevus: a lesion with
deletions of the PTCH gene. Cancer Research 1999; 59:1834-6
12. Rahbari H, Mehregan AH. Basal cell epithelioma (carcinoma) in children and teenagers. Cancer
1982; 49: 350-3
13. Domingo J, Helwig EB. Malignant neoplasms associated with nevus sebaceous of
Jadassohn. J Am Acad Dermatol 1979; 1:545-56
14. Hughes JR, O’Donnell PJ, Pembroke AC. Basal cell carcinoma in a 5-year-old girl. Clin
Exp Dermatol 1995; 20: 177
15. Beer GM, Widder W, Cierpka K, Kompatscher P, Meyer VE. Malignant tumours associated
with nevus sebaceous: therapeutic consequences. Aesthetic Plast Surg 1999; 23: 224-7
16. Goldstein GD Whitaker DC, Argenyi Z, Bardach J. Basal cell carcinoma arising in a
sebaceous naevus during childhood. J Am Acad Dermatol 1988; 18: 429-40
Copyright date: 2nd April 2001
Correspondence: C.S.J. Dunkin, Stoke Mandeville Burns and Reconstruction Surgery
Research Trust, Stoke Mandeville Hospital, Aylesbury, Bucks HP21 8AL, UK