Stereologic Study On Dermatofibrosarcoma Protuberans Surgical Margin

Purpose To analyze major factors of the infiltrative scope in the growth of dermatofibrosarcoma protuberans (DFSP) and establish the multiple linear regression model to explore the quantitative method to determine the margin of the tumor resection. Methods Retrospective analysis of the records of 63 patients with primary or recurrent DFSP was performed, who underwent treatment between 2001 and 2009 at the Primary Affiliated Hospital of Anhui Medicial University and Anhui Provincial Hospital. And the impact of factors related to recurrence of DFSP were analyzed and summarized. Eleven patients from those 63 patients were divided into trunk groups and pate groups in accordance with the growth site. The tumor tissue of these 11 patients was respectively localized in 1.5 points, 3.0 points, 4.5 points, 6.0 points, 7.5 points, 9.0 points, 10.5 points, 12.0 points according to stereological principles, and was drawn with a vertical skin. The absolute values of the relevant variables were measured using computer image analysis system. Multiple linear regression model between infiltrative scope of tumor (D) and tumor radius (R), Age (age) and gender (sex) and other variables of two group was respectively established combined with statistical method and the tumor resection scope was estimated using that Mathematical model in some special cases. Results Factors containing tumor size, growth location, depth, the number of disease, surgical resection of the rang could affect the recurrence of DFSP and invasive growth of DFSP range of variables were associated with tumor size, depth, growth location, the incidence number,horizontal length of the edge of pseudopodia / the honeycomb structure, depth of the edge of pseudopodia / honeycomb structure. The size of the tumor was absorbed into the multiple regression model about invasive growth scope of DFSP in trunk group and head and neck group, while sex, age as a balanced variable. Although the test results of equation in different groups indicated that Regression models were statistically significant ( P<0.05 ) ,it was no statistical significance for the radius of the regression coefficient(-0.01, P = 0.784) in the trunk of tumor regression equation. While the regression equation D1 = 0.1746 +0.1404 R-1.9351sex +3.0754 age1 in pate groups, the coeffcient of determination of 0.65, adjusted coefficient of determination of 0.54, indicated good model fit results. And regression coefficients(0.14)for the radius was respectively statistical significance(P = 0.001). Conclusions By analyzing DFSP in different locations, invasive growth of DFSP range of variables were associated with tumor size, depth, growth location, the incidence number, horizontal length of the edge of pseudopodia / the honeycomb structure, depth of the edge of pseudopodia / honeycomb structure. Based on the mathematical model, which was established about the growth scope of DFSP relative to tumor size, age and gender in pate groups , the tumor resection range separately could not be less than 0.8cm, 1.5cm, 3.1cm,if the longest diameter of tumor was 1.0cm, 2.0cm, 3.0cm and tumors were simultaneously ccurred in the head and neck of less than 40-year-old men.