Tumor angiogenesis as a prognostic factor in oral cavity carcinomas

Currently, lymph node metastasis and thickness of the tumor are the gold standard as a predictor of survival in patients with oral cavity squamous cell carcinoma (OSCC). However, there is a significant correlation between microvessel density and the development of cervical metastases or recurrence. Previous studies have demonstrated that head and neck cancers are able to induce an angiogenic response in experimental models. This factor shows a strong correlation with regional recurrence. In this study we propose to use angiogenesis as an independent prognostic indicator of recurrence. We evaluated the expression of tumor angiogenesis in OSCC and determinated its possible usefulness as a prognostic factor. Thirty-three cases with diagnosis of OSCC were identified from January 1985 to January 1997 in the Head and Neck Department of the Instituto Nacional de Cancerología in Mexico City. These cases were analyzed retrospectively for a minimum period of six months. All of them received a conventional complete treatment to the primary tumor and lymph node metastasis. Paraffin-embedded tumor specimens were available in all patients. The tumors were scanned and the areas of highest microvessel density (MVD) were immunostained for CD-34 using QBEnd/10 antibody. Statistical analysis included descriptive statistics, Wilcoxon test curves, and Cox's proportional hazards model for multivariate analysis. We identified 33 patients with OSCC, 16 were men and 17 women. The mean age among all patients was 58.9 years old. Based on tumor size 33.3% were T1, 27.3% T2, 12.1% T3, and 27.3% T4. The median microvessel count was 32.5. The mean percentage of MVD was 37 in patients with regional recurrence and in those patients without regional metastasis was 29 (p<0.05). 57.9% of the patients who presented recurrence had vessel counts over the median (p<0.01). In fact, 6 patients (46%) who showed more than 20% of angiogenesis expression and higher MVD presented with recurrence. Only 3 patients (23%) who had less than 20% of angiogenesis expression and lower MVD developed recurrence (p<0.01). Higher MVD was seen with increasing T and N stages; however, it did not show correlation with survival. In this study, angiogenesis expression demonstrated to be an independent factor of recurrence in patients with OSCC. It is suggested that it should be used as an independent prognostic indicator. In concordance with previous reports, we observed a significant correlation between MVD determination and recurrence of the tumor, followed by lymph node metastases and tumor size.