Gene therapy offers the possibility of new approaches to cancer treatment. The purpose of this study was to test the feasibility of suicide gene therapy for oral cancer. The human oral squamous cell carcinoma cell line HSC-4 was infected in vitro with recombinant adeno-associated virus (AAV) containing the LacZ marker gene. Expression efficiency of the LacZ gene was 26.9±1.74% at an MOI of 2000 and 100±0% at an MOI of 20000. The HSC-4 cell line was then infected with AAV containing the herpes simplex virus thymidine kinase (HSV-tk) gene and was incubated with ganciclovir (GCV). Transfection of HSV-tk gene and administration of GCV distinctly promoted tumor cell killing. In addition, a bystander effect was demonstrated in vitro. These results suggest that AAV-tk vector may be useful for gene therapy against oral squamous cell carcinoma in humans.

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We retrospectively studied 167 patients with oral squamous cell carcinoma (SCC) who were treated at our department from 1984 through 1994 to evaluate the effect of preoperative radiotherapy on outcome. Analyses were performed with Cox's proportional hazards model. Forty-five patients received preoperative radiotherapy with a mean dose of 39.0 Gy (R+S group), and the remaining 122 patients underwent surgical excision without radiotherapy (S group). These groups differed significantly with respect to the distribution of age, T and N categories, histological grade according to the World Health Organization (WHO) criteria, and mode of invasion as proposed by Yamamoto and Kohama. There was a significant negative correlation between the 5-year cumulative survival rate and N category, WHO grade, and mode of invasion. We also investigated the relationship of outcome to N category, WHO grade, mode of invasion, and treatment (between the R+S and the S groups) by Cox's proportional hazards model. Hazard ratios (weight of prognostic factors) were 3.31 (p<0.05) for N category, 3.49 (p<0.05) for WHO grade and 3.76 (p<0.01) for mode of invasion. However, the hazard ratio for treatment was not statistically significant (0.86, p=0.79). In conclusion, preoperative radiotherapy contributed very little to survival rate.

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Antitumor effects of combined treatment with interleukin-2 (IL-2) and polysaccharide Kureha (PSK) were studied in tumor-bearing C3H/He mice that were subcutaneously given murine syngeneic transplantable X5563plasmacytoma cells.The mice were divided into4experimental groups treated with (1) saline alone, (2) IL-2alone, (3) PSK alone, or (4) a combination of IL-2 and PSK. PSK (1mg/g) was administered daily in an oral dose for 20 days from the initiation of tumor cell injection. IL-2 (3500Japan Reference Units; JRU) was injected daily into the tumor from day 7 to day 20 after tumor transplan tation. Tumor growth was markedly reduced in mice receiving a combination of IL-2 and PSK, resulting in prolongation of survival. The tumor disappeared completely in 11of the 22 mice in this group.
Abundant mononuclear cell infiltration of CD4⁺cells and asialo-GM1⁺cells was observed around the tumor in the combined treatment group.
In addition, apoptosis of tumor cells was frequenthy observed in this group.Cell mediated cytotoxicity and cell surface markers of splenocytes were analyzed in mice on day 21 after tumor inoculation. Although LAK cytotoxicity against P815cells was not enhanced, NK cytotoxicity against YAC-1 increased significantly in the combined treatment group. Furthermore, cytotoxicity against X5563plasmacytoma cells was detected only in the combined treatment group. Interestingly, splenic NK cells were positive for Fas-L and perforin in all 4 groups, but there was no significant difference in the level of expression of these molecules among the groups. Surface Fas antigen on X5563tumor cells was markedly increased by PSK alone and the combination of PSK and IL-2. A detectable level of serum interferon-α(IFN-α) was observed in the combination group.
These results suggest that not only cell-mediated but also Fas-and Fas-L-mediated tumor killing are induced in tumor-bearing mice treated with a combination of IL-2 and PSK, resulting in a prolongation of survival.

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Total RNA extracted from human temporomandibular joint (TMJ) discs of patients with temporomandibular disorders (TMD) were examined by RT-PCR. The expressions of decorin, biglycan and aggrecan mRNA in the disc were demonstrated. These results suggest that human TMJ discs of patients with TMD contain decorin and biglycan. The expression of aggrecan mRNA was confirmed in calcified disc tissue.

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A 93-year-old patient with a carcinoma in the buccal mucosa (T2N0M0) received a low dose of UFT for 15 weeks. The tumor size decreased markedly (about 99%). Because of hematopoietic disturbance, chemotherapy was discontinued after 15 weeks. The patient's condition gradually improved after 3 weeks. Because the patient died of old age 8 months after presentation, the long-term response to UFT is unclear. However, the findings suggested that the tumor size was reduced by low-dose UFT. This treatment can be used in patients with poor performance status and in elderly patients.

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Human T-lymphotropic virus type I (HTLV-I) is highly endemic in Kyushu and in some areas of Hokkaido. The major transmission routes of HTLV-I are from mother to child through breast milk and from man to woman through semen. The mechanism of adult T-cell leukemia (ATL) is poorly understood. We report a case of squamous cell carcinoma of the tongue that was positive for antibodies to HTLV-I. The patient underwent radiotherapy, neck dissection, hemiglossectomy, and oral reconstruction without any complications. During therapy, there were no significant changes in cell surface markers (CD 3, CD 4, CD 8, and CD 25), PHA, or PTHrP. It is important to perform surgery, radiotherapy, or chemotherapy while carefully monitoring immunologic status.

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Bilateral chylothorax is a rare complication after left radical neck dissection (RND). In our patient, we encountered a chylous leak during RND and closed it by ligation and fibrin paste. Two days after RND, the patient complained of palpitation, chest pain, and shortness of breath. A chest X-ray film revealed large bilateral pleural effusions. Because the patient had a history of myocardial ischemia, a cardiologist diagnosed left heart failure. However, thoracocentesis showed a large amount of chyle in the pleural cavity. Chylothorax was diagnosed. Removal of the chyle and total parenteral nutrition rapidly improved the condition of the patient. On the 20th postoperative day, the pleural effusions disappeared.

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Granular cell tumor is a relatively rare tumor that develops in soft tissue at various sites and is characterized by cytoplasmic eosinophilic granules.Few reports of malignant granular cell tumor have been published. No reported case has arisen in the gingiva. We recently encountered a case of malignant granular cell tumor of the mandibular gingiva.
The patient was a 74-year-old woman. An elastic-hard tumor, measuring 22×27mm and having an irregular surface, was seen in the right side of the mandibular gingiva through the buccal mucosa. The tumor adhered to the buccal skin. The patient underwent segmental resection of the mandible under general anesthesia. The histopathological diagnosis of biopsy and resected tumor specimens was a malignant granular cell tumor.

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Pleomorphic adenoma of the submandibular gland is rare in children. Only 16 cases have been reported in the Japanese literature. In this paper, we report a pleomorphic adenoma arising in the submandibular gland of an 11-year-old girl. She complained of a mass of the left submandibular region. A hard, tender mass was palpable in this region. Computed tomography and magnetic resonance imaging showed swelling of the left submandibular gland. Under a clinical diagnosis of a benign tumor of the submandibular gland, the patient underwent total excision of the submandibular gland. The histopathological diagnosis was pleomorphic adenoma. The postoperative course has been uneventful for 2 years.
Tumors arising in the submandibular gland of children have a slightly higher incidence of malignancy and recurrence than those in adults. Therefore, total excision of the submandibular gland is indicated.

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We report a case of central fibroma in the mandible of a 35-year-old woman suffering from pachydermoperiostosis. In the molar region of the right side of the mandible, a walnut-sized, unclearly demarcated radiolucent image was detected on an orthopantomograph. Examination of a biopsy specimen resulted in a pathological diagnosis of fibroma. The tumor was operatively removed under general anesthesia, but endotracheal intubation was precluded by stricture of the pharynx, bone deposition at the lingual side of the mandible, and limitation of head tilt.Instead, tracheostomy was performed.
Two years have passed since the operation, and although there are no signs of recurrence, the patient is still being observed.

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Postoperative defects after resection of advanced tongue cancer requires considerable reconstruction of the tongue and oral floor. Ideally, tongue reconstruction should main tain the functions of swallowing, speech, and airway competence.
We designed a neurovascular latissimus dorsi flap (LD) for subtotal glossectomy. The motor nerve (thoracodorsal nerve) of the LD was anastomosed to the trunk of the hypoglossal nerve, interposed with the greater auricular nerve.
After 8 months, electromyography showed recovery of neural function of the LD, and cineradiography indicated that swallowing had improved.

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Marfan's syndrome is a hereditary disorder that principally affects connective tissue. Patients with this syndrome have various abnormalities of the face and jaws, such as malformation of the hard palate or teeth, malalignment of the teeth, temporomandibular joint dysfunction, and cleft palate. However, patients with Marfan's syndrome usually do not undergo surgical orthodontic treatment because of risks associated with cardiovascular and thoracic abnormalities. We describe our experience in the surgical orthodontic correction of maxillary protrusion and mandibular retraction in a patient with Marfan's syndrome. To avoid relapse caused by connective tissue abnormalities, intermaxillary fixation was performed by rigidly immobilizing the bones with miniplates and bonesetting screws. No complications were encountered. As of 6 years after surgery, the patient's jaw movement is virtually normal with no evidence of relapse.

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We report a case of temporomandibular joint (TMJ) ankylosis caused by ankylosing spondylitis (AS). The patient was a 31-year-old man who had suffered from AS for 8 years. Opening his mouth widely became increasingly difficult from 1991, 1 year after the onset of AS. Limited mouth opening worsened from 1997, and he was referred to our hospital (interincisal opening, 10mm). The patient performed mouth opening exercises and used an occlusal splint. His range of mouth opening became 25mm as a result of training.
We discuss the management and treatment of patients with TMJ ankylosis who have AS.

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