Basaloid squamous cell carcinoma of the mandible: report of two cases.

Basaloid squamous cell carcinoma is a rare aggressive malignancy that is a distinct variant of squamous cell carcinoma. This report presents 2 cases of basaloid squamous cell carcinoma in the gingiva. Case 1 is a 55-year-old Japanese man who presented with a painful, red, and irregular mass on the left mandibular gingiva. Case 2 is a 65-year-old Japanese man who presented with a painless mass on the right mandibular gingiva. Both tumors were diagnosed histopathologically as basaloid squamous cell carcinoma. In case 1, the patient underwent wide resection of the gingival tumor with a partial mandibulectomy and ipsilateral functional neck dissection. The mandible was reconstructed with a titanium plate and forearm flap. In case 2, the patient underwent wide resection of the gingival tumor after local irradiation (60 Gy). At the time of writing, both patients remained in good health and free of disease.

Increased glutathione level is not involved in enhanced bleomycin sensitivity in cisplatin-resistant 2780CP cells.

The cytotoxic activity of bleomycin (BLM) was evaluated in cisplatin (CDDP)-sensitive (A2780) and -resistant (2780CP) human ovarian cancer cells, and the mechanism of increased antitumor activity of BLM in the 2780CP cells was investigated. Compared with the A2780 cells, the 2780CP cells exhibited a 4.5-fold increase in resistance to CDDP, but were 4.0-fold more sensitive to BLM. The cellular glutathione (GSH) levels in the 2780CP cells were significantly higher than those in the A2780 cells, however, GSH depletion in the 2780CP cells below the levels in the A2780 cells by using buthionine-[S,R]-sulfoximine (BSO) did not affect the sensitivity to BLM. BLM decreased 5-bromo-2'-deoxyuridine (BrdU) incorporation after 24-h exposure by 27.5%-90% compared to that of the untreated control at BLM doses of 25-500 ng/ml in the 2780CP cells, but only by 1.5% -45.8% in the A2780 cells. Furthermore, in the 2780CP cells, the percentage of S-phase cells markedly decreased, with an increase in G2/M-phase cells as determined by flow cytometry after exposure to BLM. The enhanced cytotoxity of BLM in CDDP-resistant 2780CP cells could be attributed to BLM-induced G2/M accumulation and significantly inhibited DNA synthesis, not to increased cellular GSH levels.

Effect of copper and role of the copper transporters ATP7A and CTR1 in intracellular accumulation of cisplatin.

An investigation was carried out as to whether copper affected the intracellular accumulation of cisplatin (cis-diamminedichloroplatinum(II); CDDP) and whether changes in the expression of ATP7A and CTR1 were related to acquired resistance using CDDP-sensitive (KB) and -resistant (KBR/0.8, KBR/1.2) cells. Intracellular platinum accumulation and platinum-DNA adducts were significantly lower in the CDDP-resistant sublines compared with KB cells. Treatment with 750 microM CuSO4 increased the amount of intracellular platinum 1.8-, 3.2-, and 3.9-fold in KB, KBR/0.8, and KBR/1.2 cells respectively, and increased the platinum-DNA adducts by 1.9-fold in KB cells and by 3.2-fold in KBR/1.2 cells. The level of ATP7A was greatly reduced and CTR1 expression slightly decreased in KBR/1.2 cells compared with KB cells. ATP7A expression was markedly increased by exposure to CDDP with or without copper in KB cells but not in KBR/1.2 cells. CDDP and copper did not increase the level of CTR1 in KB or KBR/1.2 cells. These results indicate that a high concentration of copper causes a significant increase in the cellular accumulation of CDDP and binding of platinum to DNA independently of CTR1 expression in KB cells and CDDP-resistant sublines thereof and that the acquisition of CDDP resistance is associated with a greatly reduced level of ATP7A and a marginally lower expression of CTR1.

Reduced syndecan-1 expression is correlated with the histological grade of malignancy at the deep invasive front in oral squamous cell carcinoma.

BACKGROUND: Although many histopathological characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, no factor is completely accurate and unequivocal. This study evaluated the association between the loss of syndecan-1 expression and the histological grade of malignancy at the deep invasive front in O-SCC. METHODS: The expression of syndecan-1 at the invasive tumor front of O-SCC was examined immunohistochemically using archived tissue from 72 cases. The mean age of the patients was 62.5 years (range: 23-90 years) and the male-female ratio was 1.3:1 (41 men, 31 women). There were 26, 24, 11, and 11 cases classified as stages I-IV respectively. The correlation between the intensity of syndecan-1 immunostaining and the clinicopathological factors, especially the histological grade of malignancy at the deep invasive front (invasive front grade) was analyzed. RESULTS: Of the 72 cases, seven (9.7%), 29 (40.3%), 36 (50.0%) showed strong, intermediate, and weak or negative syndecan-1 staining respectively. There were significant differences between syndecan-1 expression and prognosis, differentiation, and pattern of invasion at the deep invasive front. Moreover, the invasive front grade scores, based on the intensity of syndecan-1 staining, were 5.6 +/- 1.0, 8.0 +/- 2.1, and 10.2 +/- 2.3 points with strong, intermediate, and weak or negative intensity respectively; and the difference was significant (P < 0.0001). Patients with intermediate or strong intensity for syndecan-1 had significantly better prognoses than did those with negative or weak intensity (P = 0.0138). CONCLUSION: This study demonstrated that the reduced expression of syndecan-1 seems to be a useful marker of histological malignancy at the deep tumor invasive front and may be a useful prognostic factor in O-SCC.

Utility of diffusion-weighted images using fast asymmetric spin-echo sequences for detection of abscess formation in the head and neck region.

OBJECTIVE: The objective of this study was to evaluate the utility of new diffusion-weighted magnetic resonance images (DWI) using fast asymmetric spin-echo (FASE) sequences for the detection of abscess formation in patients with phlegmon in the oral and maxillofacial regions. METHODS: We compared diffusion-weighted images using FASE sequences with those using the gradient-echo type of echo-planar images (EPI) in 10 control volunteers and 10 patients with phlegmon in the oral and maxillofacial regions. RESULTS: Many kinds of tissues in the oral and maxillofacial regions were relatively well visualized in all subjects on FASE-DWI, but not well on EPI-DWI. Apparent diffusion coefficients calculated from FASE sequences in abscess areas of patients with phlegmon were significantly lower than those in abscess-free areas; however, apparent diffusion coefficients calculated from EPI were not significantly different due to prominent distortion in small sample size study. CONCLUSIONS: We could accurately recognize the presence of abscess formation within inflammatory tissue in 5 patients with phlegmon using FASE-DWI. As an additional magnetic resonance examination, FASE-DWI might be useful in the detection of abscess formation in the oral and maxillofacial regions.

The relationship of the histologic grade at the deep invasive front and the expression of Ki-67 antigen and p53 protein in oral squamous cell carcinoma.

BACKGROUND: Although many histopathologic characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, accurate, and unequivocal factors have not been clearly identified. The purpose of this study was to evaluate a potential association between the histologic grade of malignancy at the deep invasive front and the expression of Ki-67 antigen and p53 protein in O-SCC. METHODS: The expression of Ki-67 antigen and p53 at the invasive tumor front area of O-SCC was examined by immunohistochemistry of archived tissue from 62 cases. The mean age of patients was 60.7 years (range: 37-89) and the male-female ratio was 1.6:1 (38 men, 24 women). There were 20, 17, 14, and 11 cases classified as stage I to stage IV, respectively. The correlation between the intensity of immunostaining for Ki-67 antigen and p53 and the histologic grade of malignancy at the deep invasive front (invasive front grade, IFG) was analyzed. The expression of Ki-67 antigen and p53 in normal oral epithelia (10 cases) was also investigated. RESULTS: The mean Ki-67 labeling index (LI) in the O-SCC samples was 32.8 +/- 12.0% (n = 62). The mean total score of IFG (IFG score) was 9.1 +/- 2.7 points (n = 62). There was a significant linear correlation between the IFG score and the Ki-67 antigen (gamma = 0.651, R2 = 0.596, P < 0.0001). Of 50 tumors examined, 27 (54.0%) exhibited p53-positive nuclear immunostaining. The staining patterns for Ki-67 antigen and p53 were similar. Both Ki-67-LI and p53-positive status were significantly correlated with the IFG scores. CONCLUSION: The findings of this study demonstrate that overexpression of Ki-67 antigen and p53 at the deep tumor invasive front of O-SCC is associated with histologic grade of malignancy.

Dental rehabilitation using an implant-supported overdenture after repair of a fracture in a severely resorbed edentulous mandible: a case report.

Treatment of mandibular fracture in senior citizens with severely resorbed edentulous mandibles is extremely difficult. Such treatment must achieve successful osteosynthesis and restore functional mastication. A severely resorbed (Class V) mandible was successfully reconstructed with an autogenous bone graft on the inferior border of the mandible and a titanium mesh plate after a failed attempt to fix the fracture. After the placement of endosseous implants in the mandible, the patient was rehabilitated with an overdenture to restore masticatory function.

Immunohistochemical study of syndecan-1 down-regulation and the expression of p53 protein or Ki-67 antigen in oral leukoplakia with or without epithelial dysplasia.

BACKGROUND: Leukoplakia is an oral pre-cancerous lesion that sometimes develops into squamous cell carcinoma. Therefore, leukoplakia with epithelial dysplasia is useful for studying carcinogenesis at the cellular level. The purpose of this study was to evaluate a potential association between the loss of syndecan-1 expression and the expression of p53 protein and Ki-67 antigen, and to identify reliable markers for predicting malignant changes in oral leukoplakia with epithelial dysplasia. METHODS: Changes in the expression of syndecan-1, p53, and Ki-67 were examined immunohistochemically in 43 cases of oral leukoplakia with or without epithelial dysplasia. The subjects were categorized as: none, 13 cases; mild dysplasia, 5 cases; moderate dysplasia, 17 cases; and severe dysplasia, 8 cases. The expression of these molecules in normal oral epithelia (22 cases) was also investigated. RESULTS: Strong syndecan-1 expression was observed on the surface of keratinocytes in normal epithelium. Immunopositivity was lost gradually as the extent of epithelial dysplasia increased. In normal epithelium, p53 and Ki-67 appeared mainly in the basal cell layer, while they were more widely distributed in leukoplakia. Specifically, significant changes were observed in the labeling index of p53 and Ki-67 in leukoplakia as epithelial dysplasia progressed from mild to moderate or severe. CONCLUSION: Our results reveal that overexpression of p53 protein and Ki-67 antigen, and down-regulation of syndecan-1 expression in the lower part of the epithelium, are associated with dysplastic changes. Therefore, the down-regulation of syndecan-1 expression may be the most important reliable marker for dysplastic changes.

Prevalence of hepatitis viral infection in dental patients with impacted teeth or jaw deformities.

OBJECTIVE: The prevalence of infection with hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis G virus (HGV), and transfusion-transmitted viruses (TTV) was evaluated in patients with impacted teeth or jaw deformities. STUDY DESIGN: Of 486 patients, 268 had serum samples available for retrospective TTV DNA and HGV RNA assays. In addition, the sera of 404 patients were assayed for HB surface antigen and the sera of 340 were assayed for HCV antibody. RESULTS: HGV RNA was detected in 3 of 268 patients (1.1%), and TTV DNA was detected in 60 of 268 (22.4%). Of 404 patients, 3 had HB surface antigens (0.7%). Furthermore, 13 of 340 were HCV-seropositive (3.8%). The rate of infection was similar between patients with impacted teeth and those with jaw deformities, respectively, as follows: 1.1% versus 0%, respectively, for HBV prevalence; 4.1% versus 3.2% for HCV prevalence; 1.8% versus 0% for HGV prevalence; and 22.9% versus 21.4% for TTV prevalence. CONCLUSIONS: Universal precautions to prevent hepatitis and TTV infection during oral surgical procedures are important.

Risk factors for late cervical lymph node metastases in patients with stage I or II carcinoma of the tongue.

BACKGROUND: Many histopathologic parameters in squamous cell carcinoma of the tongue have been identified as predictive factors for cervical lymph metastasis. However, predictive factors for occult cervical lymph node metastases and the criterion for elective therapy remain inconclusive. This study analyzed the clinicopathologic factors associated with late cervical lymph node metastases in patients with carcinoma of the tongue. METHODS: The clinicopathologic features of 50 consecutive patients seen between January 1985-December 1996 with previously untreated stage I or II squamous cell carcinoma of the tongue were reviewed. All patients were treated with partial glossectomy without elective neck dissection. Their mean age was 54.5 y (range, 23-90 y) and the male-female ratio was 1.2:1 (27 men and 23 women); 30 cases were stage I, and 20 cases were stage II. Clinicopathologic factors were analyzed to determine factors predicting late cervical lymph node metastasis. RESULTS: The overall cervical lymph node metastasis rate was 14.0% (7 of 50). Clinicopathologic factors significantly associated with the development of cervical lymph node metastasis were tumor size (> or =30 mm), tumor depth (> or =4 mm), differentiation, mode of invasion, microvascular invasion, and histologic grade of malignancy. In a multivariate logistic regression analysis, moderately differentiated squamous cell carcinoma of the tongue with tumor depth > or =4 mm had predictive value for late cervical lymph node metastasis and diminished overall survival (odds ratio, 10.0; p =.02; hazards ratio, 7.0; p =.039). CONCLUSIONS: The findings of this study demonstrate tumor depth > or =4 mm moderately differentiated squamous cell carcinoma of the tongue have a substantially higher rate of late cervical metastases. In the basis of these data, it is our recommendation that this be used in the decision to electively treat the neck.

Primary neck management among patients with cancer of the oral cavity without clinical nodal metastases: A decision and sensitivity analysis.

BACKGROUND: A standardized neck management strategy for oral cancer patients without clinical nodal metastases remains to be established. Consequently, a decision and sensitivity analysis of two neck management protocols, involving either prophylactic neck dissection or careful observation, was conducted using the Oral Cancer Registry of Kyushu, Japan. METHODS: We calculated probabilities of subclinical nodal metastases and 5-year survival using the registry data. A two-way sensitive analysis was conducted using the probabilities and parameters of the complete nodal metastasis resection rate (x) and a utility rating that describes the health state induced by dissection (y) compared with the neck condition in a careful-observation group. RESULTS: We solved the threshold curve for y and x for the expected utility between the two groups. The results showed that prophylactic neck dissection must guarantee a complete resection of subclinical nodal metastases with no disadvantage to health state to be evaluated as equally satisfactory as careful observation. CONCLUSIONS: Careful observation involving standardized systematic preoperative and postoperative screening of the neck seems preferable to prophylactic neck dissection for oral cancer patients without subclinical nodal metastases.

Preoperative histologic assessment of head and neck lesions using cutting needle biopsy.

OBJECTIVE: This study assessed the clinical utility of cutting needle biopsy in which a newly developed Monopty biopsy instrument (MBI) (Monopty, Bard Urologic Division; Covington, Ga) was used in the preoperative assessment of head and neck lesions. STUDY DESIGN: Needle biopsies were performed with the MBI in 16 cases of head and neck lesions that included lesions in lymph nodes, salivary glands, palate, and soft tissue. RESULTS: High-quality histopathologic specimens were obtained without complications in all biopsies performed, and the diagnostic target tissue was obtained in 15 of 16 cases. Diagnoses made from MBI needle biopsy specimens were consistent with the final diagnoses made from subsequent surgical materials in 14 cases, and the accuracy rate was 88%. None of the samples demonstrated significant rush artifacts or obscuring blood, both of which are problems commonly associated with manual biopsy techniques. CONCLUSIONS: This technique offers a safe and effective means of obtaining adequate tissue for the histological assessment of head and neck lesions.

Hypercalcemia associated with parathyroid hormone-related protein at the terminal stage of uncomplicated squamous cell carcinoma in the head and neck region.

BACKGROUND: Parathyroid hormone-related protein (PTHrP) is mainly responsible for hypercalcemia in squamous cell carcinomas (SCCs). METHODS: We retrospectively checked the appearance of hypercalcemia among 33 patients who died with head and neck SCC. Serum concentrations of C-terminal region of PTHrP (C-PTHrP) were measured in 15 of them. The intracellular PTHrP expression was immunohistochemically stained in 42 SCC sections obtained from the 33 before the appearance of hypercalcemia. RESULTS: Hypercalcemia appeared in 24 of the 33, and increased serum C-PTHrP levels were confirmed in 11 of 12 hypercalcemic patients. PTHrP was identified in all SCC sections, and a stronger intensity than in normal squamous epithelia was observed in 50% of those obtained within 1 year before the onset of hypercalcemia. CONCLUSION: A high incidence of PTHrP-induced hypercalcemia was shown among patients dying with head and neck SCCs. The intracellular increase in PTHrP might be observed preceding hypercalcemia.