Oral Squamous Cell Car-cinoma with an Unusual Clinical Manifestation: A Case Report.

Squamous cell carcinoma (SCC) is the most com-mon malignant tumor of the oral cavity and one of the ten most common causes of death. It arises from dysplastic oral squamous epithelium. Considering the pathogenesis of SCC, a smooth and intact surface in this lesion is not a usual finding. In this paper, we report an extremely rare case of oral SCC in buccal mucosa presenting as an exo-phytic lesion with smooth and intact surface, very unusual for oral SCC.

Clinical view of the exophytic lesion with a smooth surface in the buccal region. Small yellow papules are seen on the surface of the lesion.

Introduction

Approximately 94% of all oral malignancies are squamous cell carcinoma (SCC). The annual incidence and mortality rates vary considerably between different races, genders, and age groups. In the United States this is 7.7 per 100,000.[1] As with so many carcinomas, the risk of intra-oral cancer raises with increasing age especially for males.[1 - 4] Individuals with oral SCC are almost aware of an alteration in an oral cancer site for 4-8 months before seeking professional help. There is minimal pain during the early growth phase and this may explain the delay in seeking professional care. If the health care professional does not have a high index of suspicion, an additional several weeks or months may elapse before a biopsy is performed.[1]

Oral SCC has various clinical presentations such as exophytic, endophytic, leukoplakic and erythroplakic, all showing visible changes in the surface.[1 , 5]

In the present paper, we report an unusual case of exophytic oral SCC with a smooth surface.

Case report

A 75-year-old female patient was admitted to the Department of Oral Medicine, in Mashhad University of Medical Sciences, in October 2005, with the chief complaint of a painful mass in the left buccal mucosa which was first noticed by the patient two weeks earlier with a gradual increase in size. Intra-oral examination revealed a normal-colored firm exophytic lesion with a smooth surface on the left buccal mucosa adjacent to premolar-molar region and a size of approximately 2.5 × 1.5 cm. Small yellow papules were seen on the surface and the superior border of the lesion (Figure 1).

Figure 1

The patient had no complaint of anaesthesia or paraesthesia in the area. Extra-oral examination revealed no lymphadenopathy. Medical history indicated type II diabetes mellitus.

Considering the smooth surface of the lesion and its location, salivary gland tumors and mesenchymal tumors were considered in differential diagnosis.

The lesion underwent an incisional biopsy under local anesthesia. The excised specimen was submitted for histopathological examination, which revealed a malignant neoplastic proliferation of stratified squamous epithelial cells as sheets or islands of cells with keratin pearl formation, invading to the connective tissue (Figure 2).

Figure 2

Dyskeratosis, cellular pleomorphism and mitotic activity was observed in tumoral cells (Figure 3).

Figure 3

The definite diagnosis was squamous cell carcinoma (Grade I). The patient was referred to the oncology department where an intra-oral excisional biopsy was performed. Histopathological evaluation reconfirmed the diagnosis of SCC. The patient, however, died three days after surgery because of poor management of diabetes.

Discussion

This is an unusual case of oral SCC in a 75-year-old female patient presenting an exophytic lesion with a smooth and intact surface.

Invasion of malignant epithelial cells into the connective tissue with keratin pearl formation (H&E staining; ×40).

Invasion of malignant squamous islands into the connective tissue (H&E staining; ×100).

Considering the pathogenesis of SCC, all presentations in this case are associated with changes in the surface as expected for epithelial lesions; since, on rare occasions, squamous cell carcinoma may commence at a small location on the surface, burrow and undermine the subepithelial tissue in such a manner that the lesion appears mostly as a smooth surfaced exoplytic lesion.[6]

The diagnosis of the presented case emphasizes that even in smooth-surfaced rapid-growing oral lesions, SCC should be considered in the differential diagnosis and this needs a careful examination and management by both medical and dental practitioners.