EARLY DETECTION OF MOUTH CANCER

In this Department, apart from treating head and neck lesions (mouth, pharynx, larynx, head and salivate glands tumours) we try to achieve an increase on early detection mouth cancer.

The incidence of cancer in general, and respiratory tract and high aeroalimentary tract cancer in particular, is increasing in developed countries. The combination of several risk factors such as the ageing of the population, toxic habits (smoking and drinking), together with a lack of hygiene and oral control are responsible for this increase. At present, in the mouth there are between 12 and 15 cases per 100,000 inhabitants/year in the male and between 2 to 4 cases per 100,000 inhabitants/year in women. In the long run the survival rates of epithelial tumours (they hardly reach 50%) have not increased in the last 20/25 years.

The modern treatments have not managed to improve survival. However, radical surgery and aggressive treatments with chemotherapy and/or radiotherapy have enhanced the physical and psychological morbility. Due to the fact that more than 60% of mouth cancer cases are bigger than 2cm when diagnosed, their prognostic is worse than the one for smaller lesions. This is because the increase from 2cm to 4cm involves a change in the clinical stage, from I to II, and the survival possibilities in five years’ time are reduced in one third. Survival rates in five years’ time are more than four times higher in localised cases than in metastasic ones.

It is necessary to diagnose it in early stages and, in doing so the tumour becomes curable. However, mouth tumours still appear very advanced in the consultations despite being easily diagnosed. That is the reason why despite having improved the treatments we do not observe better survival rates. Mouth carcinoma behaves as the rest of the tumours.

The cells stem from the epithelium cells. The cancerous cells continue their growth and infiltrate and destroy the surrounding tissues and can metastasise through lymphatic and/or hematic channels and cause the growth of secondary tumours in other organs, known as metastasis.

Most of the lesions in the mouth are bening, but can appear to be malignant. At early stages oral carcinomas can appear as small and innocent induration areas, erosion, erythema or keratosis. These carcinomas remain asymptomatic until they ulcerate. Because of this variability in the oral carcinoma signs, we need to have an accurate clinical judgement and a vast experience in order not to cause diagnostic errors.

As it has been proved in several occasions and was ratified at the European Conference on Dentist and Cancer Prevention in Copenhagen in June 1990, that dentists play an important role in the early detection and prevention of cancer, what certain authors call secondary prevention. The Instituto Oncológico has been doing a mouth cancer prevention campaign in collaboration with the Basque Country dentist consultations since 1994.

We attend all the necessary consultations with no bureaucratic formalities, at no expense and in the shortest period of time. We have designed a form to fill in with information referred to the patients, which is introduced in a database. With a statistic programme we study the effects on the early detection of the mentioned explorations.

We would like to collaborate with other doctors who would be willing to take part in this campaign, especially those who work in areas where risk patients are frequent.

Besides early detection an exploration of the mouth allows the detection of pre-malignant lesions. The two pre-malignant lesions that are best known and are more frequently defined (described since the 1950s) are leucoplasias, and less frequent but more evil the eritoplasias, mostly displasic or carcinomatosic. These lesions can sometimes be simultaneous. We can not forget the lichen planus, whose presence increases the risk both in men and women. And it is obvious that if we know of the presence of these pre-malignant lesions we can approach them. Even a periodical control can diagnose any malignant change.