Cadherin Expression Is Not Associated with Metastasis or Histological Grade in Oropharyngeal Squamous Cell Carcinomas
OC Ukpo, WL Thorstad, JS Lewis. Washington University, Saint Louis, MO
Background: Cadherin expression has been shown to play an important role in metastasis in head and neck squamous cell carcinoma (SCC). Specifically, loss of E-cadherin and concomitant increase in N-cadherin expression promotes local invasion and metastasis. Human papilloma virus (HPV)- related oropharyngeal squamous cell carcinomas have a higher propensity to metastasize than their keratinizing-type counterparts. However, cadherin expression specifically in oropharyngeal SCC has not been examined. The purpose of this study was to evaluate E- and N-cadherin expression in oropharyngeal SCC and to correlate with clinical and pathological features.
Design: 123 oropharyngeal SCC patients with clinical follow up information were identified from an approved cancer database. Tumors were graded as follows: keratinizing (1), non-keratinizing (3), or hybrid/non-keratinizing with maturation (2). Immunohistochemistry was performed for p16 and graded 0 to 4. Immunohistochemistry was performed for E- and N-cadherin. Staining was graded according to presence and then intensity (0= No staining, 1= weak, 2= moderate, 3= strong).
Results: The tumors had the following histologic breakdown: Type 1: 27 (21%), Type 2: 23 (19%), Type 3: 73 (60%). E-cadherin expression was present in 123 (98%) of the specimens (no stain- 2%, weak- 9.5%, moderate- 55.1%, strong- 33.3%). N-cadherin expression was present in 17 (11.5%) of the specimens (no stain- 87.1%, weak- 9.5%, moderate- 2%). Neither E- nor N-cadherin expression was associated with histological grade (OR= 1.67 p=.082; OR=4.26 p =.228, respectively). E-cadherin staining grade was not associated with nodal or distant metastasis (OR= 8.50 p=.098; OR= 1.00 p=.963 respectively) nor was N-cadherin (OR= 4.26 p=.228; OR= 1.00 p=.935 respectively). Neither cadherin was associated with p16 expression, either. In follow up, expression of neither E- or N-cadherin was associated with death from disease (p = 0.995; p=.964, respectively).
Conclusions: Despite the numerous studies suggesting cadherin expression to be associated with metastases and outcome in head and neck SCC, our data suggests that it is not a predictor for nodal and distant metastasis in oropharyngeal SCC, specifically. Even with non-keratinizing (poorly differentiated) morphology, we still observed strong staining for E-cadherin. Our results suggest that mechanisms independent of cadherin expression must explain the early and frequent metastases that occur in oropharyngeal SCC.
Category: Head & Neck
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 153, Tuesday Afternoon