Significance of neo-angiogenesis and immuno-surveillance cells in squamous cell carcinoma of the tongue

Original article

English

Juma O. Alkhabuli

Department of oral pathology, Faculty of Dentistry, University of Sharjah, UAE

Libyan J Med, AOP: 070110 (published 7 January 2007)

Abstract

Background: Neo-angiogenesis is an essential process in physiological and pathological conditions. However, it is a complex process. Several studies demonstrated that intra-tumoural microvessel number is a significant predictor of metastasis and clinical outcome in many tumours, including oral malignancies. The immuno-surveillance cells, mast cells and eosinophils are implicated in the biological behaviour of tumours. Nevertheless, their function in tissues is uncertain. Mast cells are involved in homeostatic regulation of blood vessels as well as host defence. In some malignancies, high mast cell den¬sity has been found to correlate with favourable prognosis. How¬ever, others reported unfavour¬able associations. Tumour as¬sociated tissue eosinophilia is a well-known phenomena. It has been associated with good and poor prognosis. However, the role of eosinophils in tumours re¬mains controversial. Therefore, this study was designed to in¬vestigate the prognostic value of microvessel, mast cell and eosi¬nophil densities in the context of clinico-pathological parameters and survival in squamous cell carcinoma of the tongue. Materials and Methods: Anti-CD105 and anti-tryptase mono¬clonal antibodies were utilized to highlight and count microves¬sels and mast cells respectively in 8cases of tongue squamous cell carcinoma. Eosinophils were demonstrated using carbol chro¬motrope histochemical stain. The densities were counted per mm2and correlated with patients’ out¬come and other clinico-pathologi¬cal parameters using non-para¬metric tests and student’s t-test. Clinically, the cases were divided into 4 main groups depending on survival time, lymph-node or dis¬tant metastasis.
Results: The 5 year survival was significantly lower in patients with a low mast cell density than those with a high density (p=0.006, Kruskal-Wallis test). The sur¬vival group-A demonstrated sig¬nificantly higher mast cell and mi¬crovessel numbers than group-D (p=0.007, student’s t-test) respec¬tively. Patients with well- differen¬tiated squamous cell carcinoma had significantly higher numbers of mast cells when compared to patients with poorly differenti¬ated squamous cell carcinoma (p<0.05, student’s t-test). The lymph node involvement correla¬tion between the survival group-A and survival group-D was also significant (p=0.001, Mann-Whitney U test). Conclusion: Data from this study indicates that accumulating mast cells in tumours play a part in inhibiting tumour progression and is potentially angiogenic in tumours. Keywords: Tongue squamous cell carcinoma; Angiogenesis; Mast cells; Eosinophils, Link/DOI: