Dermatología Pediatrica

AUTHORS

ADDRESS FOR CORRESPONDENCE

Dr Neerja Puri
# 626, Phase II, Urban Estate,
Dugri Road, Ludhiana.
Punjab. India.
Cell :09814616427 

ABSTRACT

A two day old male infant presented with giant melanocytic naevi over the back, neck, right axilla and both shoulders with multiple congenital melanocytic naevi over the buttocks,arms chest, abdomen and left little toe nail. Giant melanocytic naevi are very distressing to the patients. Also the significant risk of malignant change warrants prophylactic removal. However, their large size poses a great surgical challenge.

KEY WORDS:  Congenital melanocytic naevi; giant: hairy naevus : malignancy. 

INTRODUCTION

Congenital melanocytic naevi are brown or black moles which are present at birth or which develop in the first year or so of life (brown birth marks).¹ Giant congenital naevi are greater than 20 cm in diameter. They are often found on the trunk when they are known as ‘bathing trunk' naevi. Very large, giant or bathing trunk naevi are very rare.

Congenital melanocytic naevi present as multishaded pigmented patches, oval shaped and fairly uniform in appearance.² Those with large naevi have numerous smaller satellite lesions. Most congenital naevi grow with the child and generally they become proportionally smaller and less obvious with time. However, sometimes the lesion becomes darker especially at puberty. They may develop a bumpy surface or become more hairy. The cause of congenital melanocytic naevi is unknown but they are probably caused by localized genetic abnormalities. They are formed by overgrowths of the melanocytes. Malignant melanoma, sometimes develops within congenital melanocytic naevi.³ The risk of this happening in a small or medium sized mole is very small(under 1%). Melanoma is more likely in the giant naevi (perhaps about 5% over a lifetime) especially in those that lie across the spine.⁴

We hereby report a case of a giant hairy bathing trunk naevus covering the back, neck and shoulders, along with small congenital melanocytic naevi scattered all over the body.

CASE REPORT

 A 2 days old male infant presented with a congenital large pigmented patch covering the back, neck, buttocks and axilla (Fig 1).  The lesion was black in colour with convolutions on the back. The pigmented patch over the axilla had 1-3 cm sized hair over the patch (Fig 2). There were also present small multiple pigmented satellite lesions of varying diameters (1cm to 3 cm), scattered all over the body (Fig 3). A nail bed naevus was present in the left little toe nail (Fig 4). There were no other associated congenital anomalies. Fundus examination, X ray spine, CT head and spine and ultrasound abdomen were all normal. The biopsy of the patient was taken and the histopathological findings were consistent with congenital melanocytic naevus. There were nest & cords of naevus cells filling the dermis and extending into the subcutaneous (Fig 5). The dermis consisted entirely of heavily pigmented naevus cells containing melanin. No junctional activity or evidence of malignant transformation was seen.

DISCUSSION

Congenital melanocytic naevi present as multishaded pigmented patches, oval shaped and fairly uniform in appearance. Those with large naevi have numerous smaller satellite lesions.⁵ Most congenital naevi grow with the child and generally they are proportionally smaller and less obvious with time. However, sometimes the lesion becomes darker especially at puberty. They may develop a bumpy surface or become more hairy. Rarely they fade away and may even disappear altogether.

Most small congenital naevi (less than 1.5 cm in diameter) need no specific treatment. However, it can be useful for follow up to have taken a close-up photograph of a mole with a ruler beside it. Giant hairy naevus may undergo malignant transformation in 3.7% of cases.⁶ Large congenital melanocytic naevi can be removed surgically, but surgical removal can be difficult (or impossible) and always results in scarring.⁷ Laser treatment is sometimes helpful. In selected lesions, pigmented lasers can be used to fade flat naevi, but this is not always successful.

Giant congenital melanocytic naevi may lead to severe cosmetic deformities and subsequent psychosocial problems for the child. Another important problem is the relatively high potential of giant congenital melanocytic naevi to undergo malignant transformation.⁸Management of such lesions presents an enormous difficulty.

The choice of surgical procedures depends on the consideration of the importance of the patients cosmetic appearance, the reduction of risk of malignancy and the maintaining of normal function. Excision is the surest method of removing all potentially malignant cells. However, great strides have been made in excisional surgery, but inspite of it the cosmetic results are sometimes less than satisfactory. Dermabrasion has also been successfully employed with gratifying cosmetic results, but leaving behind naevus cells in the deep dermis has been a serious objection in the procedure.⁹

Most congenital naevi do not need specific treatment. However, it can be useful for follow up to have taken a close up photograph of the mole with a ruler beside it. This makes it easier to see if there has been any growth or change in it sometime later.

Congenital naevi are sometimes surgically removed. Reasons include :

• Unsightly appearance
• Worry about risk of melanoma
• Difficulty in keeping an eye on the mole (e.g scalp, back or sole).
• Change (darkening,lumpiness etc) within the lesion or unexpected growth.
• Melanoma like appearance (i.e irregular shape, variegated colour).

Congenital naevi, depending on size and location, may have a significant impact on cosmesis. Giant congenital naevi place individuals at an increased risk for the development of melanoma at the site of the naevus.¹⁰ For giant congenital melanocytic naevi, the risk of developing melanoma has been reported to be as high as 5-7% by the age of 60 years.¹¹ A few studies suggest that the risk of melanoma may be greater in those with giant congenital melanocytic naevi with more satellite lesions or a larger diameter. The malignant potential of small or midsized congenital melanocytic naevi is controversial. However, many experts believe that a small naevus does not significantly increase the lifetime risk of developing melanoma.

The case report of giant bathing trunk naevus is being presented because of its rarity. 

REFERENCES

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