Expanding regions of epithelial dysplasia are often found around oral squamous cell carcinoma (SCC). Failure to resect such regions can lead to local recurrence or a second primary cancer. However, epithelial dysplasia is difficult to distinguish from normal mucosa. Moreover, the border of epithelial dysplasia is difficult to define. To clearly demarcate the border of expanding regions of epithelial dysplasia surrounding SCC, we used staining with 3% iodine solution to decide the surgical margin. We quantified telomerase activity in tumor, in epithelial dysplasia, and in normal epithelium. We also studied pathological findings. Thirty-one primary cases of oral SCC surrounded by iodine-unstained regions were investigated. Fluorescence-based TRAP was used to quantify telomerase activity. Pathological studies used HE staining, PAS staining, and PAS staining after α-amylase digestion test. We obtained the following results: On pathological examination, the iodine-unstained region was recognized as dysplasia of varying degrees around the tumor. In the iodine-unstained region, the higher the degree of dysplasia, the higher was the rate of negative staining for PAS. Telomerase activity was 52.7U/μgP in SCC, 37.2U/μgP in epithelial dysplasia, and 2.9U/μgP in normal epithelium. When the degree of dysplasia was compared with the telomerase activity, a higher degree of dysplasia was found to be associated with an increase in the telomerase activity. These results indicate that cells that have already acquired unrestricted proliferative capacity have increased epithelial dysplasia in iodine-unstained regions. Therefore, the epithelial dysplasia should be resected with the SCC. Staining with iodine solution is useful in defining regions of epithelial dysplasia.
Lymph node metastasis is the major cause of the poor prognosis of tongue carcinoma. To investigate the mechanism of lymph node metastasis, we developed three lymph node metastasis sublines (RSC 3 E 2, RSC 3 E 2 R, and RSC 3 LM) from 4 NQO-induced tongue squamous cell carcinoma in the rat (RSC 3). LM and E 2 R cells metastasized to the popliteal lymph nodes after injection into the foot pad. Labeling of LM cells with the fluorescence dye Ca-AM revealed fluorescence in the popliteal lymph nodes immediately after injection of the labeled cells. These findings indicate that (1) LM cells have spontaneous metastatic potential, (2) E 2 R cells have experimental metastatic potential, and (3) E 2 cells are nonmetastatic. In vitro and in vivo invasion assays showed that LM cells have higher invasive ability than the other two types of cells. In addition, gelatin zymography revealed that only LM cells carried an activated form of matrix metalloproteinase-2 (MMP-2). These results suggest that the high motility and activated form of MMP-2 may be important for intravasation of LM cells into lymphatic vessels in the primary tumor, leading to spontaneous lymph node metastasis. This model could be useful for investigating the mechanism of lymphatic metastasis of tongue carcinoma cells.
Acinic cell carcinoma usually arises in the parotid gland and rarely occurs in the gingiva. We report a curious case of acinic cell carcinoma presenting as a caulescent lump in the left retromolar region of a 64-year-old woman, resulting in a clinically difficult diagnosis. The first clinicodiagnostic impression was epulis fibrosa or fibromatosa. After surgical excision of this lump, the histologic diagnosis was an acinic cell carcinoma. The clinical details of this case are discussed with related problems on the basis of the literature.
A case of undifferentiated carcinoma with socalled lymphoepithelioma of the sublingual gland associated with Epstein-Barr (EB) virus is presented. A 60-year-old man was referred to our hospital because of swelling of the right sublingual and submandibular regions. Clinical, radiographic, and pathological examinations revealed carcinoma of the right sublingual gland. He therefore underwent surgical resection of the tumor and reconstruction with a free forearm flap. We recognized high antibody titers of EBNA (EBV nuclear antigen), VCA-IgG, and VCA-IgA on blood tests. EBV-encoded small nuclear RNA 1 (EBER 1) hybridization signals were strongly expressed, and EB virus DNA was detected on Southern blot analysis of a metastatic lymph node. These findings strongly suggest that EB virus participated in carcinogenesis. The histological diagnosis was Epstein-Barr virus associated with undifferentiated carcinoma with lymphoid stroma of the sublingual gland.
Trigeminal neuralgia is associated with various symptoms. Its causes are also diverse, including oral infection, tumorous lesions, and vascular compression of nerves. Trigeminal neuralgia with intracranial disease is rarely encountered in daily medical practice. We describe our experience with trigeminal neuralgia caused by intracranial disease. This case was diagnosed by early head CT scan and improved after cerebral nerve surgery.
Vascular leiomyoma is a benign tumor of the smooth muscle that originates in the blood vessels and mainly occurs on the limbs in middle-aged to elderly women. It rarely occurs in the oral cavity. We report a case of vascular leiomyoma arising in the palate. A 36-year-old man visited our department because of a hemispherical tumor in the palate. The clinical diagnosis was a salivary gland tumor, and excision of the tumor was performed. Histopathologically, the tumor was diagnosed as vascular leiomyoma. The patient's postoperative course has been good, with no evidence of recurrence as of 1 year after the operation.
An angiomyoma is a benign tumor usually located in the lower extremities of middle aged. women. It is rarely found in the oral region. We report the clinical features and immunohistochemical findings of angiomyoma arising in the lower lip of a 51-year-old man. He was referred to our clinic because of a painless mass in the lower lip. The tumor measured about 10×10mm and was a localized, elastic soft, mucosal swelling of the lower lip. The tumor was resected. Microscopically, the tumor consisted of masses of leiomyoma and endothelial cells. The immunohistochemical analysis showed positive reactions for desmin and HHF-35 in angioendothelial cells and in most of the tumor cells. The histopathological diagnosis was angiomyoma.
We report on a 51-year-old man who had subpontic osseous hyperplasia (SOH) of the mandible. SOH is a rare variant of benign exostosis which occurs on the alveolar crest below the pontic of a fixed bridge prosthesis. The histopathologic characteristics of SOH closely resemble those of osteoma. The surgical specimen of the present case histopathologically showed well formed compact bone with lamellae and Haversian systems. Although a total of 59 cases of SOH have been reported, its cause has not been clarified. In our patient, SOH may have been induced by inflammatory stimulation due to periodontitis of the adjacent teeth.
Ameloblastic fibro-odontoma is a rare odontgenic tumor resembling ameloblastic fibroma, but showing inductive changes that lead to the formation of dentine and enamel. The tumor occurs primarily in young patients. The molar region of the mandible is more often affected than the other sites. We present a case of ameloblastic fibro-odontoma in a 13-year-old boy. He was referred to us because of a swelling with pain in the molar region of the left side of the mandible. Radiographically, the lesion showed a multilocular radiolucency with numerous calcification foci from the impacted second molar to the third molar region of the left side of the mandible. Histologically, the tumor was composed of cellular connective tissue with proliferating odontogenic epithelium in the form of strands and islands, and dentinoid and tooth-like hard tissue. Enucleation of the tumor was performed under general anesthesia, and there has been no recurrence as of 3 years 8 months after operation.
Thyroglossal duct cyst is the most common nonodontogenic cyst in the neck and is thought to originate from the epithelial remnants of the thyroglossal duct. Thyroglossal duct cyst rarely arises in the dorsum of the tongue. We present a rare case occurring in the anterior part of the dorsum of the tongue. The patient, a 46-year-old woman, was referred to our department because of swelling and pain of the tongue. The mass of the tongue was elastic soft and purplish red with a clearly demarcated border. It measured 31×34mm. A cystic lesion was suspected on ultrasonography and magnetic resonance imaging. The lesion was enucleated for a clinical diagnosis of a cyst of the tongue. The definitive diagnosis was thyroglossal duct cyst. There has been no evidence of recurrence as of 1 year 10 months after the operation, and function of the tongue is normal.
We report a rare case of migration of a fishbone. The patient was a 56-year-old woman who had swallowing and pharyngeal pain when eating. Radiographic and computed tomographic examinations showed a foreign body in the floor of the mouth. An intraoral attempt at removal was unsuccessful. Nine days later, the fishbone had penetrated the floor of the mouth, passed through the hyoid bone, and migrated to the anterior cervical region. The foreign body was surgically removed and was found to be a fishbone.
Prosthetic rehabilitation of maxillectomy defects is effective, and surgical reconstruction is usually not indicated. Although fabricating a maxillary obturator is relatively easy in patients with teeth, it can be challenging in edentulous patients. Placement of implants can dramatically affect the quality of life of edentulous patients who undergo maxillectomy. However, conventional ready-made bar attachments are associated with difficulty in stability and retention of the prosthesis. We used a milling-bar attachment to circumvent these problems in a series of patients prospectively studied between 1997 and 1999. The aim of this study was to evaluate clinical results in 4 patients who were followed up for longer than 1 year. All implants were installed in the remaining maxilla. The overall survival rate of the implants was 100%. Masticatory and speech function markedly improved by using maxillary obturators supported by milling-bar attachments.