调节性 T 细胞而非 TIL（肿瘤浸润淋巴细胞）与基底细胞癌肿瘤浸润深度相关

Basal cell carcinoma (BCC) is the most common skin malignancy worldwide. Current evidence suggests tumour-infiltrating lymphocytes (TILs) may influence the clinical outcomes of patients with BCC. The present study aimed to profile the infiltrative characteristics of stromal TILs and regulatory T cells (Treg cells) in the tumour centre (TC), tumour periphery (TP), and normal adjacent tissue (NAT) of BCC.

A total of 111 samples from 43 cutaneous BCC cases were examined for TIL (CD3+) and Treg cell (FOXP3+/CD3+) expression using immunohistochemical techniques. The correlations of Treg cells with TILs, invasion depth, and tumour morphological risk were analysed.

We identified a high mean proportion of Treg cells within the tumour (TC = 46. 9%, TP = 56. 1%, NAT = 51. 8%) despite a relatively low median of TILs (TC = 12. 7%, TP = 10. 3%, NAT = 3. 6%), supporting the classification of BCC as a cold tumour. A significant positive correlation was observed between the proportion of Treg cells and sTILs ( = 0.

325, p < 0. 001), suggesting a predominant role of TILs in the infiltration of Treg cells. An inverse correlation discovered between Treg cells and tumour invasion depth (r = 0. 36, p = 0. 017) might indicate Treg cells anti-tumour capacity in BCC.