Squamocellular Carcinoma of the Skin: Clinicopathological Features Predicting the Involvement of the Surgical Margins and Review of the Literature

Abstract

Background: The new AJCC classification has highlighted some particular risk factors for squamous cell carcinoma (SCC) relevant for prognosis. Incomplete excision is not infrequent in SCC. The aim of this study is to examine features that can predict an incomplete excision on the basis of the new AJCC classification and to review the literature on this topic. Materials and Methods: 81 SCC patients were included. All patients were submitted to excisional biopsy with a margin of at least 4 mm from the clinical edges as recommended. Histological characteristics of the lesions analysed were maximum diameter, grading, site, Breslow thickness, Clark level, deep tissue invasion (neural, bone, muscle), presence of ulceration and positivity of the margins. Results: The average Breslow thickness was 3.93 mm. Out of the 81 patients included, 14 showed involved margins. The 2 parameters that were implicated in predicting involvement of the margins in the multivariable model were Breslow thickness and location of the lesion on the ear or lip. Grading was not associated with involvement of margins. Conclusion: According to the new AJCC classification, this study could be useful to plan the most suitable surgical technique in order to avoid the risk of incomplete surgery.

European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 2. Treatment

“…In clinically well-defined low-risk cSCCs with a diameter of less than 2 cm, a margin of 4 mm has achieved cure rates of 95%e97% in prospective studies [14,20]. Nevertheless, tumour diameter is only an approximate reflection of the actual degree of tumour aggressiveness and additional histological features may increase the risk of margin involvement, even in smaller tumours [21]. Therefore, guidelines consistently propose margins between 4 mm and 6 mm for tumours lacking high-risk features [16,22e25].…”

Japanese Dermatological Association Guidelines: Outlines of Guidelines for Cutaneous Squamous Cell Carcinoma 2020

“…The present guidelines recommend 4–6 mm for the low‐risk group and 6–10 mm for the high‐risk group in consideration of the differences among systematic reviews and guidelines. However, since complete resection is impossible in some cases even by following these recommendations, 147‐149 it is permitted to set a large resection margin for more assured tumor resection. This is why we expressed our recommendations as 4–6 mm (or more) for low‐risk groups and 6–10 mm (or more) for high‐risk groups.…”

Current strategy of squamous cell carcinoma diagnosis and treatment

“…Проспективные исследования показали, что при хирургическом иссечении плоскоклеточных карцином диаметром <2 см низкого риска (четко определяемых клинически) отступ 4 мм обеспечивает излечение в 95-97 % случаев [96,97]. Тем не менее небольшой размер опухоли неточно отражает истинную степень ее злокачественности, и дополнительные гистологические характеристики могут повышать риск вовлечения краев резекции даже при небольших опухолях [98]. Таким образом, в руководствах предлагается использовать следующие поля: от 4 до 6 мм для опухолей без признаков высокого риска [93,[99][100][101][102].…”