L. Gáspár (1), P. Vágó (2)
Department of Oral and Maxillofacial Surgery, Central Military Hospital, Budapest,(1)
Department of Stomatology, Haynal University of Health Sciences, Budapest, Hungary(2)

Abstract

The experience with 1089 laser interventions of oral precancerosis is surveyed. Different surgical lasers (CO2, Nd YAG and CO2+Nd YAG) were used. The differentiated technique elaborated on by the authors ensures, besides the safe removal of the tissues involved, the greatest preservation of oral functions. In precancerosis, coagulation was performed by a 5 W defocused CO2 laser beam: in verrucosus cases, vaporisation was done by using a 10 to 15 W focused beam: in erosive cases, excision was performed using a 20 to 25 W focused beam. The Nd YAG and CO2+Nd YAG interventions were performed with defocused and focused beam in the cases of blood clothing disorders. Thus, it became possible to remove only the pathologic tissues. Wound healing leaves minimal scarring and the therapeutic result is favourable , from both functional (nourishment, speech, mimic) and aesthetic points of view. Following one laser treatment in 1007 of 1089 patients (92.4%), a symptom-free condition could be observed. Postoperative pain and oedema are minimal: the majority of the patients are capable of resuming work by the second postoperative day. It is established that one of the most important oral surgical indications of the CO2 laser treatment is represented by the presence of leukoplakias.

Key words: surgical lasers, precancerous states, oral cavity

Introduction

The cancer mortality rate in Hungary is especially high: it ranks as the second leading cause of death. During the past 25 years, the cancer mortality rate in males increased by 150%. and a considerable, threefold increase took place in the number of malignancies of the oral cavity. In 1995, every seventh male cancer death was due to tumours of the oral cavity.

Considerable efforts have been made all over the world to achieve early diagnosis of precancerous conditions. It is an ever-urgent necessity to introduce a program of regular oral cancer screening. The early diagnosis of precancerous conditions and tumours of the oral cavity will detect a greater number of patients whose management will emphatically raise questions regarding the use of the laser beam.

The favourable experience obtained with the laser beam will certainly help to establish its superiority over a few traditional procedures, at least until new and more effective methods appear. Currently, substantial knowledge is accumulating based on the laser therapy of oral precancerosis for assessing the opportunities of laser treatment and critically evaluating its effectiveness.

The literature data on oral leukoplakia and his own research results are surveyed by Bánoczy 1 . She stresses the importance of the elimination of etiologic factors and suggests conservative therapy that, in case of failure, is followed by surgical approach. Regular follow-up is essential the significance of dysplasia is emphasised. After conservative therapy (with vitamin A), Schettler and Horch 22 and Panders et al. 3 observed a recurrence rate of 40 to 55%. Following surgical incision, relapse was seen by Silverman et al., 4 Vedtofte et al., 5 and Mincer et al. 6 in 20 to 33% of the cases. Cryotherapy suppressed the relapse rate below 20%. 7-14

Following removal of the leukoplakia with the CO 2 laser, a less than 10% relapse rate was reported on by Frame et al., 15 Frame, 16 Burian and Höfler, 17 Roodenburg, 18 Rhys Evans et al., 19 Tuffin and Carruth, 20 and Horch et al. 21 Such initial favourable results, on smaller patient samples, were also described by us in previous publications. 22-26

Regarding the laser surgical treatment of the precancerosis, three basic methods are mentioned in the literature:

a. Treatments with defocused beam 19,20
b. Vaporisation with focused beam 18,21 and
c. Laser excision. 16

The interventions can be performed by CO2, Nd YAG and combi (CO2+Nd YAG) lasers, both by a handpiece and by an operation microscope adjusted with a micromanipulator.

Our own experience and the data of the literature provide unambiguous proof that oral precancerosis can be effectively treated by laser surgery. Complications are few, and the aesthetic results are favourable. This paper is intended to summarise our experience gained in this field thus far.