The invasive front of carcinomas. The most important area for tumour prognosis?

Various molecular events of importance in tumour spread like the gain and l oss of adhesion molecules, secretion of proteolytic enzymes, increased cell proliferation and the initiation of angiogenesis occur at the tumour-host interface (invasive front). We have hypothesised that molecular or morpholo gical characteristics at the invasive front area of various carcinomas may reflect armour prognosis better than other parts of the tumour: Consequentl y, we recently developed a simple malignancy grading system restricted to t he deep invasive front area of head and neck squamous cell carcinomas. This grading system proved to have additional prognostic value over the establi shed prognostic factors. All similar studies performed so far have confirme d the high prognostic significance of the invasive front grading in squamou s cell carcinomas at different locations. In this review paper we describe the system and the hypothesis on which it has been developed. The reproduci bility of the grading is acceptable for further extended studies. Interesti ngly, observations of similar invasive front alterations in different adeno carcinomas suggest that the invasive tumour front may underlie the biologic al aggressiveness of carcinomas of glandular origin, as well. Hypothesis. The invasive front is the most important area for prognostic de termination of several types of carcinomas.