[Oral cancer. Prognostic aspects].

The present knowledge regarding growth and progression of intraoral squamous cell carcinoma is still fragmentary. The 5-year survival for these patients is poor. In order to improve the prognosis in this highly lethal cancer, it is important to gain more knowledge about its biological behaviour. In the present paper we suggest that certain cells at the invasive margins of the tumors are most important for prognostic evaluation of the cancer. We have studied the expression of a group of cell membrane bound carbohydrates (blood group antigens) on these deep, invasive cells and found an association between loss of expression of one of these structures and invasion and spread of the cancer cells. Furthermore, we have found a hitherto not reported prognostic value of Rhesus blood groups. We suggest that chromosome instability reported to occur on chromosome 1 in some oral squamous cell carcinomas in some way involve the Rhesus gene that is located in the same area of chromosome 1.