頬皮膚欠損の部位別・サイズ別再建アルゴリズム：単一施設後ろ向き研究

Background: The rising incidence of cutaneous non-melanoma skin cancers underscores the need for individualized reconstruction, particularly for cheek defects that pose distinctive anatomic and functional challenges. This study aimed to analyze reconstructive patterns for cheek skin lesions and to develop a simple, site- and size-based algorithm for small- to medium-sized defects. Methods: We retrospectively reviewed 129 consecutive patients treated between 2022 and 2025 for primary basal cell carcinoma, squamous cell carcinoma, or benign cheek skin tumors. After excision, defects were reconstructed with primary closure, local flaps, or skin grafts. Associations between the largest clinically measured lesion diameter (used as a proxy for the post-excision defect size), anatomical subsite, histopathology, and reconstructive technique were evaluated using ANOVA or Kruskal-Wallis tests, chi-square tests, and Spearman's correlation. Results: The mean lesion diameter was 19.75 ± 12.93 mm. Reconstruction was performed using local flaps in 62 patients (48.06%), primary closure in 53 (41.09%), and skin grafts in 14 (10.85%). Larger defects were more frequently managed with grafts or flaps (F(2,110) = 4.84, p = 0.010), and lesion size correlated with reconstructive complexity (Spearman's ρ = 0.229, p = 0.015). Lesion location was also significantly associated with the reconstruction method (χ²(10) = 48.29, p < 0.001; Cramér's V = 0.44). Margin-negative (R0) excision was achieved in 95.35% of cases, with a low recurrence rate (3.91%) and complication rate (1.56%). Conclusions: Lesion size and anatomical location are key determinants of reconstructive strategy for cheek skin defects. In this cohort, lesions ≤ 20 mm were predominantly managed with primary closure, whereas lesions > 20 mm more frequently required flap reconstruction or skin grafting. This size-based split is cohort-derived and should be interpreted as a pragmatic framework that requires external validation.