# Introduction he skin is a complex and the largest organ in the body. Because of its complexity a wide range of diseases can develop from the skin including tumors from surface epidermis, epidermal appendages and dermal tissue. 1 Histopathological study is one of the most valuable means of diagnosis in dermatology. But it has its own limitations; sometimes no definitive diagnosis can be made. In case of tumors, difficulties in diagnosis may also arise. For instance, distinction of squamous cell carcinoma from pseudoepitheliomatous hyperplasia or from keratoacanthoma is not always possible. 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. First clear cut study of carcinogenesis was made by Sir Percival Pott in 1775. He discovered that soot is a carcinogen in chimney sweepers. 4 Sir Jonathan Hutchinson in 1887 recognized association between arsenic administration and subsequent development of both cutaneous and systemic malignancy. Hyde recognised ultraviolet light as a carcinogen. Thus by the beginning of this century, the carcinogenic potential of both chemicals and radiation was recognised. Yamagiwa and Ilchikawa in 1918 described experimental induction of skin cancer by chemical carcinogens. In 1945, Khanolkar described the Dhoti cancer. # II. # Methodology This study of "incidence of squamous cell carcinoma in Karnataka" was carried out for 18 months from November 2005 to April 2007. # a) Inclusion Criteria Malignant tumors of epidermis (Squamous cell carcinoma) were included. # b) Exclusion Criteria All non-neoplastic lesions and mesenchymal tumors of epidermis were excluded. All benign tumors of epidermis were excluded. Brief clinical history and findings were noted in each case. Nature of biopsy either incisional or excisional biopsy was noted. Specimens were fixed in 10% formalin for 12-36 hours and the gross features were examined. Extent of sampling depended on the size of tumor as follows. Further, tissue was processed and embedded in paraffin blocks. Sections of 5 to 6 micron thickness were taken and stained with hematoxylin and eosin and studied. Special stains were used wherever necessary. According to WHO classification of skin tumors (1974) 5 F with male preponderance (85%) and maximum number of cases occurred in the anogenital region (55%). The peak incidence was seen in the 5 th decade. ? 2 = 44.643; p < 0.000 (Highly Significant) Most of the tumors were between 0.5 to 6 cms. All squamous cell carcinomas were graded according to Broder's grading. Fifteen cases were of Broder's grade-1, showing atypicality of cells, infiltration of dermis with more number of malignant epithelial pearls with occasional mitotic figures. Six cases were of Broder's grade-2, showing more than 50% of differentiated squamous cells, with few epithelial pearls and occasional mitotic figures. Five cases were of Broder's grade-3 showing more than 25% of differentiated squamous cells, with atypicality of cells, individual cell keratinization, an occasional epithelial pearl and a few mitotic figures. IV. # Discussion 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. Total of 790 specimens of neoplasms were received, Out of these, tumors of epidermis, epidermal adnexae and melanogenic system were 54, constituting 6.83%. In the present study it was observed that malignant epidermal tumors were the most common (61%), and others (39%). In the present study, squamous cell carcinoma accounted for maximum number (67.5%) followed by others (32.5%).. Squamous cell carcinoma accounted for maximum number of cases of skin cancer by Chakravarthy RC et al. 6 Budharaja SN et al. 7 and Deo SV et al. 8 as in the present study. In the present study, 57% of squamous cell carcinomas occurred over the genitalia. This figure is high when compared to the series of Chuang CY et al. 10 When anogenital cancers were excluded, squamous cell carcinoma occurred commonly over the extremities, which was consistent with findings of Reddy DJ and Rao KV. 9 Chakravarthy RC et al. Most squamous cell carcinomas of the skin are well differentiated. 11 The present study correlate with the above studies having maximum number of squamous cell carcinomas (Grade I and Grade II) accounting for 82% of all cases. V. # Conclusion Skin tumors constitute a small but significant proportion of patients with cancer. Unlike in the Western countries, SCC is the commonest histologic variety. 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 some cases rare entities and problems of differential diagnosis encountered may solved with histochemical and/or electron microscopy. In this century, the carcinogenic potential of both chemicals and radiation cannot be ignored. ![cases were classified. Infective conditions were omitted. c) Statistical Methods Applied 1. Cross tabs Procedure 2. Chi-square test 3. Descriptive statistics III. Results a) Squamous cell carcinoma In the present study, twenty-seven cases were encountered, peak incidence was in fifth decade (33%) T Global Journal of Medical Research Volume XIV Issue III Version I © 2014 Global Journals Inc. (US)](image-2.png "") 1SiteNumberPercentageof casesHead and518.5neckExtremities726.0External1555.5genitalia? 2 = 7.357; p < 0.25 (Significant) 2Age inNumberPercentageyearsof cases40-49933.350-59726.060-69622.270-79518.5? 2 = 1.45; p < 0.767 (Not Significant) 3SexNumberPercentageof casesMale2486Female414 4TypeNumberPercentageof casesSquamous2696cellcarcinomaVerrucous14carcinoma 5Grade NumberPercentageof casesI1558II623III519IV00 6Type of tumorBudhraja SN et al. 7Chakravarthy RC et al. 6Deo SV et al. 8Present studySquamous cell carcinoma49.02%64.3%55.8%67.5% 72014YearVolume XIV Issue III Version I( ) FAge in yearsReddy DJ et al. 9 Number of cases Percentage Number of cases Percentage Present study40-492431.5893350-591114.4772660-6933.9562270-79--519 8MaleFemaleNumber of cases Percentage Number of cases PercentageChakravarthy RC et al 64371.622128.38Reddy DJ and Rao KV 94761.842938.16Present study2385415 9Head and neckExtremitiesExternal genitaliaNumber of cases%Number of cases%Number of cases%Reddy DJ and Rao KV 925343446--Chakravarthy RC and Choudhri 616253453--Present study518.57251555.5 © 2014 Global Journals Inc. (US) * Ackerman's Surgical Pathology JRosai Ackerman Elsevier 9 * Tumors of epidermal appendages. Histopathology of skin. 8 th ed. Philadelphia: Lippincott Raven EDavid RosalieERagsdale BD 1997 * The structure and development of skin. 4 th ed. In: Fitzpatrick, Textbook of Dermatology in General Medicine DHChu ARHaake KHolbrook CALoomis 2003 McGraw-Hill * Non-melanoma skin cancer and other epidermal skin tumors. 7 th ed. In: Rook, Wilkinson, Ebling's Textbook of Dermatology RMMackie AGQuinn Blackwell 2 2004 * Histological typing of skin tumors RejSeldon International Classification of Tumors 1974 * Malignant neoplasms of skin in Eastern India RCChakravarthy Choudhri Ind J Cancer 5 1 1968 * Malignant neoplasms of the skin in Pondicherry (a study of 102 cases) SNBudhraja VcvPillai Ind J Cancer 1972 * Surgical management of skin cancers: Experience from a regional cancer centre in North India SVDeo Ind J Cancer 42 2005 * Malignant neoplasms of the skin DJReddy KVRao Ind J of Dermatology and Venerology 30 1964 * Squamous cell carcinoma. A population based study in Rochoster CYChuang APPopescu Arch Dermatol 126 1990 * Tumors skin. Boyd's Textbook of Pathology ACRitchie 1990 9