Reduced αB-crystallin staining in perineural invasion of head and neck cutaneous squamous cell carcinoma

Objective: Perineural invasion (PNI) in cutaneous squamous cell carcinoma of the head and neck (CSCCHN) carries poor prognosis. Tumor markers associated with neurotropism in CSCCHN have not been identified. Our objective was to study the expression of αB-crystallin in CSCCHN with neurotropism. Study Design: Cross-sectional review of pathologic specimens. Setting: Tertiary care center. Subjects and Methods: Tissue from patients with CSCCHN with clinical PNI who underwent surgery between 1998 and 2005 was immunostained for αB-crystallin. In addition, non-PNI CSCCHN and normal nerve sections were also stained. Staining intensity was calculated by the histologic, or H, score (product of the intensity and proportion of tumor cells stained). The H-score ranged from 0.0 to 3.0, with 0 indicating negative staining in all cells and 3.0 indicating strong staining in 100 percent of cells. Results: Tissue was available in 15 clinical PNI CSCCHN patients. The analysis was also carried out in 14 non-PNI patients matched by stage and four normal greater auricular nerve (GAN) sections. The mean H-score was 0.56 for CSCCHN with PNI, 1.06 for non-PNI CSCCHN, and 3.0 for normal nerves. The difference in H-score between PNI and non-PNI CSCCHN was statistically significant (P = 0.04). Conclusion: CSCCHN with clinical PNI has decreased staining for αB-crystallin. This finding further demonstrates the differences between clinical PNI and non-PNI CSCCHN tumors. Additional studies are required to identify cell surface markers expressed by CSCCHN that confer neurotropism capabilities.