INTRODUCTION

Squamous cell carcinoma of head and neck is one of the most common neoplasias, reaching world mortality rates of 20/ 100 thousand inhabitants (Landis et al., 1998). In Brazil, available recent estimates refer that there were 8 thousand new cases of mouth cancer in 1998 (Ministério da Saúde, 1998). Epidemiological data have pointed towards diet and smoking as the main factors of malignant transformation in the group, in addition to viral infections and genetic susceptibility (Gallo et al., 1996; Soresen et al., 1997; McKaig et al., 1998).

Among head. and neck tumors, oral cavity is the most affected site, amounting to about 30% of all cases and approximately 6% of al cancers that affect the human body. Among oral cavity neoplasia, tongue cancer and lip cancer have the same incidence of 20 to 50% of all cases of cancer in the region, and there are about 5.5 thousand new cases every year in the United States (Mark, 1998).

Shah et al. (1990) inferred that the most important prognostic factor in head and neck tumors is the presence of cervical metastases, approximately decreasing 50% the survival time if there are cervical nodules affected by metastatic disease. They reinforced that they are present in about 40% of the patients with squamous cell carcinoma of the head and neck.

Treatment of tongue neoplasia, in the presence of clinically evident cervical nodules, is performed with resection of primary lesion followed by cervical dissection. However, this approach is disputable in cases without evidence of localregional metastases (N0), especially if the primary lesion could be resected without cervical access (Byers, 1998).

The present study aimed at evaluating the index of clinically occult local-regional metastases of tongue tumors T1 and T2 (UICC) in its anterior two thirds.

MATERIAL AND METHOD

We used a sample of 20 patients, who had tongue squamous cell carcinoma, T1 and T2 in its intraoral portion, without clinical evidence of cervical metastases, treated at Service of Head and Neck Surgery at Hospital de Base de São José do Rio Preto, between July 1990 and June 1999.

It is a study that analyzed medical files, after authorization of patients or family members. Among patients, 10 were treated with partial glossectomy and 10 were submitted to the referred surgery associated with supra omohyoid neck dissection, a clinical-surgical intervention advocated at the service on the occasion. All patients were followed monthly in the first post-operative year, bimonthly in the second year, once every three months in the 3rd year, once every 4 months in the 4th year, and every 5 months in the 5th year, and so on. If there was evidence of nodules, or cervical masses, fine needle aspiration biopsy was conducted for histopathologic diagnosis.

RESULTS

Out of 20 patients included in the study, we observed a mean age range of 64.5 years varying from 46 to 81 years when diagnosed. Male subjects amounted to 65% of the sample, with 13 subjects and 35% or 7 cases were female patients.

As to habits, 85% of the patients were smokers and had smoked for an average of 39.2 years before diagnosis. Abuse of alcohol was present in 40% of the patients and it has happened for an average of 33.5 years before symptomatology.

The main complaint was tongue wound, reported by 90% of the patients, followed by pain in 40% and odynophagia in 15% - these symptoms had been present for an average of 2.3 months before the medical appointment. According to UICC, at staging, we observed that 60% of the sample was of T2 - 12 cases, and 40% of T1 stage - 8 cases.

Treatment of patients consisted of partial glossectomy associated with supra omohyoid neck dissection in 50% of patients; the other were treated only with partial glossectomy. Out of the total number of cervical dissection, only one had a lymph node affected by neoplasic disease, according to anatomic pathological diagnosis, located on the area II, ipsilateral to the lesion. Among the 10 patients treated only with partial glossectomy, 4 developed clinically evident cervical metastatic disease, cervical nodule palpable at physical exam and histopathological diagnosis, performed with fine needle aspiration biopsy during follow-up, and the mean time for diagnosis of these nodules was 15 months after initial treatment, and they all manifested on area II ipsilateral to the lesion. Out of 5 patients who had clinically occult cervical metastases, two were stage TI and 3 were stage T2.

We also observed the presence of associated pathologies, and the most incident one was hypertension, manifested in 54% of the sample, followed by diabetes mellitus in 18%, depression, Parkinson disease and chronic renal failure-each of them had incidence of 9%.

DISCUSSION

Tongue tumor is one of the most incident tumors of squamous cell carcinoma of head and neck. In general, it affects patients over the age of 65 years, but it does not spare those who are on the top of their work capacity. It is more frequent in male subjects, representing approximately 70% of the cases. The main risk factors continue to be smoking and abuse of alcohol.

The tongue, because it is an organ with very rich lymphatic drainage, has high rates of metastatic dissemination of cancers, even when they are initial lesions that are normally subdinical.

In the present study, we observed that 4 patients out of 10 treated only for primary lesion, had clinically evident cervical metastases in their follow-up, usually 15 months after initial treatment. Out of 10 patients submitted to partial glossectomy and supra omohyoid neck dissection, one had a lymph node affected by the disease, after anatomic pathological analysis of cervical dissection material. It, therefore, amounts to 25% of the sample showing subclinical lymph node affection in ipsilateral area II after they had presented N0 neck at initial physical exam.

Results obtained from this study are similar to those reported by the literature, in which Lydiatt et al. (1993) reported in a study with 156 patients who had T1 and T2 lesions of intraoral tongue that 20.4% of N0 cases became pathologically positive after cervical resection. Hicks et al. (1998) in a study with 79 patients, with similar diagnosis, had an index of 25% of N0 patients that became N+ after the surgery.

Yen et al. (1999), in a study with 50 patients with Tl and T2 intraoral tongue lesions, obtained the following figures: 36% of subclinical lymph node metastases, and area II ipsilateral to the lesion was the most affected; 34% of positive metastatic nodules in patients who had normal CT Scan and ultrasound, and 20% of patients who had normal results with intra-operative freezing test still presented positive results for metastatic dissemination in the cervical resection material after the analysis of paraffin sections.

Haddadin et al. (1999), in a study with 226 patients with diagnosis and stages similar to the anterior descriptions; reached a level of 38% of occult metastases, survival rate of 80.5% in 5 years for subjects treated only with primary lesion resection plus supra omohyoid dissection; those treated only with primary lesion resection had a survival rate of 59.7%of cases. Patients submitted to cervical dissection and/or radiotherapy only when presented clinically evident metastases had a survival rate of 44.8% in 5 years. In that study, it was also observed in the latter group, that there were high levels of extra capsular dissemination of affected lymph nodes - justifying, therefore, the need to treat the head and neck that have such lesions.

CONCLUSION

Tongue tumors, even at initial stages, present a high index of subclinical metastases that should be treated even without indications of their existence.

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* Physician with the Department of Otorhinolaryngology and Master Degree under course at Faculdade de Medicina de São José do Rio Preto /SP.
** Doctorate Degree in Biology and Head of the Department of Research at Faculdade de Medicina de São José do Rio Preto /SP.
*** Doctorate Degree in Otorhinolaryngology, Director and Head of the Discipline of Otorhinolaryngology at Faculdade de Medicina de São José do Rio Preto /SP.

Affiliation: Faculdade de Medicina de São José do Rio Preto.
Address for correspondence: Fernando Drimel Molina - Rua Tamoio, 51 - casa 4 - 15014-040 São José do Rio Preto/ SP - Tel/fax: (55 17) 231-4257.
Article submitted on March 24, 2000. Article accepted on July 13, 2000.