Epithelial-mesenchymal interactions are crucial to cancer metastasis and invasion of oral squamous cell carcinoma. We have established a modified in vitro fibronectin degradation/invasion assay in which tumor cells are co-cultured with fibroblasts. Using this assay, we measured the invasive activity of three cell lines derived from human oral squamouscell carcinomas of different grades. According to Yamamoto Kohama's classification, OSC-20 was classified as grade 3, OSC-19 as grade 4C, and HOC313 as grade 4D.HOC313 showed stronger invasiveness when co-cultured with fibroblasts than did OSC-20 or OSC-19. Knockdown of the matrix metalloproteinase gene MT1-MMP in either the cancer cells or the fibroblastscompletely inhibited in vitro invasiveness, suggesting that MT1-MMP might be a key trigger of protease activation cascades.
A rare case of adenoid squamous cell carcinoma of the tongue is reported. A 61-year-old woman with cardiac sarcoidosis was an inpatient at our hospital. She was referred to us because of a white lesion on the tongue. An incisional biopsy was done, and the lesion was diagnosed to be a mucoepidermoid carcinoma. Partial glossectomy was performed with the patient under general anesthesia. Histologically, the surface layer of the neoplasm was squamous cell carcinoma. An adenoid squamous pattern was found in deep layers where pseudoglandular spaces containing exfoliated acantholytic tumor cells were observed. These pseudoglandulae were negative for alcian blue staining, but positive for anti-cytokeratin immunostaining. Consequently, the lesion was diagnosed to be an adenoid squamous cell carcinoma. As of 3 years and 6 months postoperatively, there has been no evidence of recurrence.
Solitary fibrous tumor (SFT) is a rare benign tumor that occurs mainly in the pleura; however, it can also arise in other extrapleural sites, including the oral cavity. In 2002, the World Health Organization classified SFT as a tumor of intermediate malignancy characterized by metastases to the lung, bone and, rarely, liver. We report a case of SFT in the left side of the buccal region. A 52-year-old woman visited our hospital in June 2005 because of a painless swelling on the left side of the buccal region. A CT scan and MRI showed awell-defined solid tumor in the left side of the buccal region. The tumor was surgically resected, and histopathological examination revealed a SFT. There has been no recurrence ofthe tumor for 18 months since the operation. We review the literature with regard to the clinicopathologic features of SFT.
Synovial chondromatosis is a non-neoplastic monoarticular condition that is uncommon in the temporomandibular joint (TMJ). A 31-year-old patient with synovial chondromatosis of theleft TMJ was followed for 5 years before operation. Magnetic resonance images showed the longitudinal course of synovial chondromatosis. The synovial membrane increased in thickness and then protruded into the joint cavity and produced loose bodies. The MR findings of this case show the longitudinal course of synovial chondromatosis of the TMJ over time.
Extraction of the lower third molars is a common procedure in oral surgery. After the procedure, disturbance of the lingual nerve is rare. In patients with mild injury, conservative treatment with drugs and stellate ganglion block may relieve symptoms. However, in severe cases, microsurgical treatment of the injured lingual nerve should be performed as soon as possible. We operated microsurgically in 3 patients with lingual nerve disorders that occurred after mandibular third molar extraction. After the operation, senses other than taste recovered in all patients, and taste was improved in 2 of the 3 patients. After the operation, 2 patients were satisfied, and the other was almost satisfied. No patient was dissatisfied. The concept for the management of such an iatrogenic lingual nerve injury remains unclear. In addition, we discuss treatment planning for iatrogenic lingual nerve injury
Oral malignant melanomas were clinically studied in 10 patients treated at the Department of Oral and Maxillofacial Surgery If, Osaka University Graduate School of Dentistry, and the Departments of Dentistry and Oral Surgery, of Tenri Hospital and of Higashiosaka City General Hospital from 1987 through 2003. The subjects were 9 men and 1 woman aged from 43 to 82 years. The tumor location was the maxillary gingiva in 5 patients, the hard palatein 2, the lower gingiva in 2, and the buccal mucosa in 1. Two patients were in Stage I, 7 in Stage II, and 1 in Stage III. As for the histological invasion grade, 1 patient was in Level I, 3 in Level II, and 4 in Level III. Tumors were removed surgically in 8 patients, 6 of whom received chemotherapy after operation. The other 2 patients received either carbon ion radiotherapy or chemotherapy alone. Six patients died of distant metastasis. Distant metastasis occurred frequently in patients with deeply infiltrating tumors and/or multiple cervical metastatic lymph nodes. The histological invasion level and the number of metastatic regional lymph nodes may be useful for predicting the outcomes of patients with oral malignant melanoma.