Histopathological Analysis of Metastatic Tumours of the Oral Cavity with Example of Metastatic Renal Cell Carcinoma to Tongue

Background/Aim: Metastatic tumours make up only 1-3% of all malignant tumours of the oral region; however, in 25% of the total number of cases, they are the first sign of the disease. Usually, metastases in the oral region are followed by poor prognosis. Metastases are more common in the mandible than in the maxilla; in soft tissues, they most commonly occur in the attached gingiva and tongue. Malignant tumours of the lung, breast, kidney, liver, bone, prostate, thyroid gland, skin, colon and female genital organs most commonly give metastases in this region, usually in patients aged 40 to 70 years.

Case Report: We present a patient aged 79 years with a tumour change in the body of the tongue. After histopathological and immunohistochemical analysis (Cytokeratin, Vimentin, CD 10 positive tumour cells, Cytokeratin 7, Cytokeratin 20 negative tumour cells), there was a suspicion of metastasis of clear cell renal carcinoma (CCRC). Due to renal cancer, the patient had left kidney operated seven years before the diagnosis of tongue tumour.

Conclusions: Diagnosis of metastatic tumours of the oral region is a great challenge, both for clinicians and for histopathologists. Since it is a heterogeneous group of neoplasms, standard histopathological tissue processing, is not always sufficient to determine the histological type of tumour and its primary origin. In the analysis of metastatic tumours of the oral region, team work is important and careful clinical and histopathological assessment lead to definitive and accurate diagnosis.

Oral granular cell tumour: A multicentric study of 56 cases and a systematic review

OBJECTIVE

Granular cell tumour (GCT) is a benign neoplasm that originates from Schwann cells. Within the oral cavity, it usually appears as a lingual nodule and especially amongst female adults. Histologically, GCT shows a proliferation of polygonal cells with eosinophilic granular cytoplasm, which can be associated with a pseudoepitheliomatous hyperplasia (PEH). In this study, we analyse the main clinicopathological data of intraoral GCT and we compare our results with previous studies.

MATERIAL AND METHODS

We have studied a series of 56 cases of oral GCT in Spain and Brazil, and we have conducted a systematic review in PubMed, Web of Knowledge and Scopus databases, using the keywords: "granular cell tumour" and oral.

RESULTS

In our series, GCT appeared as an asymptomatic benign tumour that is more frequent in women and in the tongue. PEH was observed in 32% of the lesions. In the review, we collected 282 cases of oral GCT with a similar clinical profile; seven patients had multiple lesions, and 33% of the cases presented PEH. No cases of malignant oral GCT have been described to date. GCT is an uncommon oral benign neoplasm, mainly unique and asymptomatic, derived from Schwann cells.

CONCLUSIONS

Although the etiopathogenesis of this oral tumour is unknown, its characteristics suggest that it could have a reactive nature. Conducting a complete clinicopathological study in all intraoral GCT is fundamental in order to dismiss other entities, including oral carcinoma.