|Year : 1997 | Volume
| Issue : 4 | Page : 235-237
G Ravichandran, S Premalatha
Source of Support: None, Conflict of Interest: None
A case of pagetoid melanoma is reported for its unusual site, larger size and presence of suprabasal lacunae in the histopathological study.
|How to cite this article:|
Ravichandran G, Premalatha S. Pagetoid melanoma. Indian J Dermatol Venereol Leprol 1997;63:235-7
The superficial spreding melanoma, also referred to as pagetoid melanoma comprises over 50% of melanomas. The lesion presents most frequently in the fourth or fifth decade and the commonest sites are the trunk in males, and three times as common on the leg in females. The clinical presentation is generally that of a pigmented lesion with well-defined but irregular margin. Notching of the margin is a common feature and partial regression may cause central pigment loss while extension continues peripherally. Color variation is often marked and deep shades of brown and black may be mixed with pink or violet hues. Loss of normal skin markings can be observed. The lesions may present for months or even years prior to invasive growth of the tumour. Easy bleeding, erosions or ulcerations are common. The essential pathological features are the presence of atypical melanocytes scattered in a pagetoid pattern throughout the epidermis. The large cells lie predominantly in nests in the lower epidermis and singly in upper epidermis.
| Case Report|| |
A 60-year-old woman presented with a 2-year history of itchy pigmented plaque in the left axilla. The lesion had developed from a previously existed pigmented mole at that site since childhood. Cutaneous examination showed a well-defined plaque measuring about 10cm in diameter, occupying the entire left axilla and extending to the infra axillary region [Figure - 1]. The margin was irregularly scalloped especially in the upper medial aspect. The color varied from light to dark mottled brown peripherally and pink centrally with depigmented spots. The surface of the lesion showed erosion in some areas and the skin markings were lost. On palpation it was soft, tender and freely mobile. There was no regional lymphadenopathy. Systemic including ophthalmic examination was normal except the presence of essential hypertension. Routine laboratory investigations were normal. Liver function tests, x-ray of the chest and ultrasonogram of the abdomen were also normal. Histopathological study showed large atypical melanocytes lying in clusters in the lower and singly in the upper epidermis. Suprabasal lacunae were seen [Figure - 2]. Melanophages and chronic inflammatory cells were present in the dermis. The atypical cells were DOPA positive and PAS negative. Excision and full thickness graft was done by the plastic surgeon.
| Discussion|| |
Pagetoid or superficial spreading melanoma in situ occurs on unexposed skin, frequently over the upper back in men and in the lower legs in women. [1,2] In our case the lesion was present in the axilla which is an unusual site. The size also was unusually large, 10 cm in diameter; normally they do not exceed 2.5 cm. The clinical picture was characteristic of pagetoid melanoma and the histopathological feature was the presence of suprabasal lacunae in the epidermis. This may be probably due to anaplastic changes in the lower epidermis resulting in secondary acantholysis similar to that seen in acantholytic type of solar keratosis and adenoid squamous cell carcinoma. Suprabasal bulla has been reported in the paget's disease of the breast. To our knowledge, the presence of suprabasal clefts is an unusual histopathological feature not yet reported in pagetoid melanoma in situ.
| References|| |
|1.||Rook A, Wilkinson DS, Ebling FJG, et al. Melanocytic nevi and malignant melanoma, In: Text Book of Dermatology, Blackwell Scientific Publications, Oxford, 1992;1547-1551. |
|2.||Lever WF, Schaumberg - Lever G. Superficial spreading melanoma in situ, In: Histopathology of the Skin, 7th ed, JB Lippincott, Philadelphia, 1990;783, 544. |
|3.||Premalatha S, Somasundaram V. Suprabasal bulla in paget's disease of the breast, Ind J Dermatol Venereol Leprol 1992;58:221-223. |
[Figure - 1], [Figure - 2]