he skin is a complex and the largest organ in the body. Wide range of diseases can develop from the skin including tumors from surface epidermis. The vast diversity of these lesions and descriptive data, often overlapping produces confusion in the area of nomenclature and difficulty in diagnosis. 1 Histopathological study is valuable means of diagnosis in dermatology. But it has limitations; sometimes, in case of tumors definitive diagnosis cannot be made. 2 The distinction between benign and malignant neoplasm are rather more difficult to define when they appear in skin than when found elsewhere 3 and histopathological examination is frequently required to establish a definitive diagnosis.

Diagnosis of any skin tumors can be done by correlating clinical features and histological features, which can be supported by histochemistry, immunohistochemistry and electron microscopy.

This study of "Tumors of the skin" was carried out from November 2005 to April 2007 over a period of 18 months. Inclusion Criteria: All benign and malignant tumors of skin were included.

Exclusion Criteria: All non-neoplastic lesions and mesenchymal tumors were excluded.

Brief clinical history and findings were noted. Gross features were examined; Incisional or excisional biopsy study was done to assess nature of tumors, and fixed all specimens in 10% formalin for 12-36 hours. Further, tissue was processed and embedded in paraffin blocks. Sections of 6 micron thickness were taken and stained with hematoxylin and eosin and studied. Special stains were used whenever necessary. According to WHO classification of skin tumors (1974) 4 cases were classified into:

1

During the period of 18 months from November 2005 to April 2007, out of the total surgical specimens received in Department of Pathology, for histopathological study 790 were of tumors and out of these 54 were skin tumors. Of the 54 cases, 14 were diagnosed as benign tumors and 40 as malignant tumors. The benign tumors constituted 25.92% and malignant tumors constituted 74.07%.

The study also showed there was male predominance and the male to female ratio was 2.7:1. ? 2 = 30.741; p < 0.000 (Highly Significant)

In the present study the peak age group was between 5 th and 7 th decade. ? 2 = 12.519; p < 0.000 (Highly Significant) The study showed there was male predominance with the male to female ratio of 2.7:1.

In the present study, benign tumors amounted to 14 (25.92%) out of total 54 skin tumors. In the present study, 8 cases (57%) of Seborrheioc keratosis were encountered, out of which one is melanoacanthoma. Two male patients were between age group of 60-65 years.

Gross examination showed tumor within the epidermis limited by horizontal line. (Figure 4A and 4B) ii. Keratoacanthoma Four cases of keratoacanthoma were encountered.These were solitary lesion over the expo -sed area in old males of few months duration.

Histologically, it showed a central keratin filled crater and proliferation of epidermis form the base of the crater into the dermis. Dermis showed chronic inflammatory cell infiltrates.

iii. Warty dyskeratoma Two cases of warty dyskeratoma were encountered. These were solitary lesions over the scalp in old females.

Histologically, it showed hyperkeratosis, acanthosis, parakeratosis and cup shaped invagination of the epidermis filled with keratinous material. Dermis showed chronic inflammatory cell infiltrates.

Skin tumors constitute a small but significant proportion of patients with cancer. Skin tumors are an ideal subject for study from clinical, morphological and therapeutic point of view and are so ubiquitous that they can affect people of all ages.

In this study, the WHO classification of skin tumors 5 was followed. All non-neoplastic lesions and dermal tumors were excluded from this study. However, keratoacanthoma and warty dyskeratoma have been included under benign tumors of epidermis following the recent classification of tumors of epidermis by WHO. 6 During this 18 month study period (November 2005 to April 2007) a total of 790 specimens of neoplasms were received in the Department of Path -ology, K.R. Hospital, Mysore. Out of these, tumors of epidermis, epidermal adnexal and melanogenic system were 54, constituting 6.83%.

In the present study it was observed that malignant epidermal tumors were the most common (61%), followed by benign tumors of epidermal appendages (13%), benign tumors of epidermis (11%), malignant melanogenic tumors (9%), malignant adnexal neoplasms (4%) and benign melanogenic tumor (2%).

Of these 54 cases studied, the ratio of benign (14) to malignant tumors (40) was 1:2.85.

In India, skin cancers constitute about 1-2% of all diagnosed cancers. Various cancer registries in India reported cumulative incidence of skin cancer varying from 0.5 to 2 per 1,00,000 population. 7

Skin tumors constitute a small but significant proportion of patients with cancer. The anxiety of the patients to differentiate benign from malignant tumors, can be solved by histopathology. Histopathological study is one of the most valuable means of diagnosis in dermatology and diagnosis of skin tumors can be done by correlating clinical features gross and histological appearances. In this study advance age and male preponderance seen, maybe because of excess sun and irritants exposure.

In some cases rare entities and problems of differential diagnosis encountered maybe solved with the help of histochemical and/or electron microscopic studies.

Out of 54 cases, histopathologically 40 were diagnosed as malignant and 14 as benign lesions.

The ratio of malignant to benign tumors was 2.8:1. The peak incidence of tumors was in 5th and 6th decades with a male to female ratio of 2.8:1.

Of the benign epidermal tumors, 8 (57%) were seborrheic keratosis 4(29%) keratoacanthoma and 2(14%) warty dyskeratoma.