Telomeres are considered one factor governing the life span of cells. In most immortalized cells or cancer cells, telomerase activity, which is one of the mechanisms responsible for elongation of shortened telomeres, is increased. Telomerase activity is therefore considered to play a crutial role in carcinogenesis. To study the role of telomerase activity in carcinogenesis in vivo, we investigated the relation between telomerase activity and histopathological findings of the tongue after treatment of DA rats with the carcinogen 4-NQO (4-nitroquinoline-N-oxide). Normal epithelium or epithelial hyperplasia of the tongue was found to have weak but detectable telomerase activity. Telomerase activity was considerably upregulated very early after the onset of malignant changes. Our results showed that telomerase was upregulated during early carcinogenesis of the tongue (nearly synchronized with malignant changes). This upregulation of telomerase activity may contribute to in vivo carcinogenesis.
The mechanism of carcinogenesis induced by 4-nitroquinoline 1-oxide remains poorly understood. We studied cell kinetics (BrdU, cyclin D 1) and immunohistochemically examined the relation to the cell cycle and morphogenesis (P-cadherin) to determine the mechanism of carcinogenesis. P-cadherin is a cell adhesion molecular essential for morphogenesis. It also has an important role in cell proliferation. However, the role of P-cadherin in carcinogenesis remains unclear. During the epithelial dysplasia stage of carcinogenesis, BrdU and cyclin D 1 were overexpressed significantly as compared with normal epithelial tissue (p=0.0005). The localization of cyclin D 1 and Pcadherin extended from the basal cells to the spinous cell layer. This localization of cyclin D 1 indicated that cells in the spinous cell layer were in the G 1 phase of their cell cycle. P-cadherin simultaneously appeared on their cell membrane. Our results suggest that overexpression of P-cadherin is closely related to the G 1 phase of the cell cycle and that carcinogenesis is induced by an uncontrolled cell cycle with overexpression of P-cadherin.
The objective of this study was to evaluate the suitability of free jejunal grafts for oral reconstruction. Twenty-nine free jejunal grafts have been used to reconstruct the oral mucosa after radical resection for cancer since November 1991. Postoperative oral function, including conversational intelligibility, Japanese speech intelligibility, eating ability, degree of xerostomia, and incidence of postoperative complications, was evaluated in 9 patients. Severity of post-radiation xerostomia after surgery was evaluated with the use of a 100 mm visual analogue scale (VAS). The average scores of conversational intelligibility and Japanese speech intelligibility tests were 9.9 points and 61.6%, respectively. Six patients could eat normal food, and 3 could eat soft food. By fixing the mesenteric side of the jejunum to the mandible, it was possible to restore the lingual sulcus, which facilitates the use of dentures. Xerostomia was significantly less in patients with jejunal grafts (VAS, 10 mm) than in those with other types of flaps (VAS, 45 mm). Five jejunal grafts were lost because of vascular complications. In 4 patients, an oro-cutaneous fistula developed, and closure was necessary. Two patients had mesenteric lymph node swelling 1 year postoperatively, but the excised specimen showed only non-specific inflammation. One patient had postoperative ileus as an abdominal complication and underwent surgical treatment.
Multiple primary cancers of the oral and maxillofacial area were found in 19 (6.6%) of 288 patients presenting to the Department of Oral Surgery of Kawasaki Medical School between April 1974 and March 1996. The study group consisted of 14 males and 5 females. Two patients had triple cancers, and one had multiple cancers of the oral cavity. The average interval between diagnosis of the first primary cancer and that of the second primary tumor was 5 years 9 months, and the median interval was 4 years 1 month. Three patients were in stage I, 8 in stage II, 2 in stage M, and 6 in stage N. We performed radical or multidisciplinary treatment in 16 patients, and 12 died. Eight of the 12 patients had metastasis to other organs, particularly the gastrointestinal tract and liver. Therefore, consultation with other medical specialists is essential.
Pleomorphic adenoma rarely arises in the palate of children, although it is the most common benign salivary gland tumor. We describe our experience with a rare case of pleomorphic adenoma arising in the palate of a 9-year-old boy. He had a swelling on the right side of the palate. Computed tomography revealed that a mass in the right side of palate erroded the bone of the palate. Histopathological examination of a biopsy specimen revealed pleomophic adenoma. The tumor was excised with the boy under general anesthesia. He has no evidence of tumor recurrence. However, the arrangement of the teeth was found to be abnormal 24 months after surgical treatment.
We describe a large desmoplastic ameloblastoma occurring in the mandible. Clinical and radiographic examinations 2 years after surgery revealed no evidence of recurrence, and good continuity of the mandible was reestablished.
We report a case of complex odontoma that had unique radiological features. A 25-year-old man was referred to the Department of Dentistry and Oral Surgery, Sapporo General Hospital because of swelling and pain at the right side of the mandible. Panoramic radiographs showed a lesion with a mottled appearance over an impacted wisdom tooth. Computed tomographic examination clearly showed a lowdensity mass containing some cavernous-bone-like radiopacities. The mass was diagnosed to be a mandibular tumor and was removed surgically. The impacted wisdom tooth was then extracted. Histopathological examination of the mass revealed a complex odontoma, which was not suspected before operation. To our knowledge, there have been no previous reports of complex odontoma associated with the features of this case. We therefore describe and comment on this quite rare case.
Thirty-five cases of ranula in children are reported. Most of the cysts were located in the mouth floor. The ratio of boys to girls was 1: 1.7. The average age at presentation of this lesion was 9.8 years, with a range of 3 months to 15 years. The most common symptom was swelling of the mouth floor. Marsupialization of the cyst was performed in most cases. The prognosis of most patients was good, and recurrence occurred in two patients, who were treated by marsupialization of the cyst. However, there has been no recurrence about 6 years after enucleation of the sublingual gland and marsupialization of the cyst.
Local amyloidosis was found in the right cheek of a 45-year-old woman. The tumor measured 13×18 mm and was located beneath healthy mucosa. It had s hard elasticconsistency and a relatively distinct border. A benign tumor was suspected on the basis of palpation and ultrasonic examination, and the entire tumor was enucleated under local anesthesia. Because the diagnosis of amyloidosis was confirmed histopathologically a comprehensive general physical examination was performed by a physician. Since no other medical abnormalities were found, we confirmed the diagnosis to be local cheek amyloidosis.
Aspergillosis is caused by infection with Aspergilli. It is often difficult to make an exact diagnosis before identification of Aspergilli by microbial examination because aspergillosis is difficult to differentiate from other diseases. We present a case of aspergillosis of the maxillary sinus that could be diagnosed on serological examination for Aspergilli or fungi specific sugar. A 51-year-old woman visited to our hospital because of swelling in the gingiva of the maxilla. Radical operation of the maxillary sinus was performed for a clinical diagnosis of aspergillosis of the maxillary sinus. Histopathological examination revealed Aspergilli in the extirpated tissue of the maxillary sinus. Serological examinations showed elevated serum levels of galactomannan and β-D-glucan. Galactomannan is a specific marker for Aspergilli, and β-D-glucan is specific for fungi. Both makers fell to normal levels after operation, Suggesting that serological examinations for galactomannan and β-D-glucan are useful in the diagnosis of aspergillosis of the maxillary sinus.
A rare case of causalgia after extraction of a mandibular third molar is reported. A 24-year-old woman was referred to our hospital because of left hemilingual paresthesia after removal of an impacted left mandibular third molar. After administration of antibiotics and hydrocortisone for 1 week, sensory perception was restored very slowly, but the patient became to have burning pain and allodynia on the left side of the tongue. The underlying cause was diagnosed to be causalgia. After stellate ganglion block was done four times, the burning pain began to resolve, but stellate ganglion block had to be performed 154 times to control all symptoms.
Arteriovenous malformation (AVM) rarely develops in the oral and maxillofacial region. We encountered one case of AVM in the maxillofacial region. The case was diagnosed in a 32-year-old pregnant woman. Massive hemorrhage occurred two times. Because the condition of the fetus deteriorated, emergency caesarean section was performed. Magnetic resonance imaging showed a hypervascular lesion in the right mandibular region, and AVM was demonstrated on angiography. After transcatheter arterial embolization of the feeding arteries, the lesion resolved.