Susumu Shingaki

Identification of potential biomarkers of lymph node metastasis in oral squamous cell carcinoma by cDNA microarray analysis

We surveyed the expression of 557 cancer‐related genes in 15 cases of well‐differentiated OSCC by cDNA microarray analysis. To identify potential biomarkers for lymph node metastasis, all microarray data were compared by the Mann‐Whitney test and the significance analysis of microarrays between OSCCs with and those without lymph node metastasis. The tissues of OSCCs with lymph node metastasis exhibited increased expression levels of MMP‐1, MMP‐3, uPA, integrin‐α3, paxillin, tenascin C and IL‐6 transcripts. All of these genes were included in common clusters on the Cluster/TreeView analysis, implying that functional gene groups of proteolytic enzymes and integrin‐related molecules are involved in cervical lymph node metastasis. The results of RTQ‐PCR for differentially expressed genes were in accord with those of cDNA microarray analyses, suggesting that the data obtained by microarray gene expression analyses were valid. Consistent with cooperative expression patterns, immunohistochemical analyses demonstrated that products of MMP‐1, MMP‐3 and uPA were colocalized to components of the neoplastic stroma, particularly mononuclear inflammatory cells with well‐developed eosinophilic cytoplasm. Our results suggest that expression levels of molecules involved in tissue remodeling and cell–ECM adhesion, especially MMP‐1 and integrin‐α3, can provide an accurate biomarker system for predicting the risk of cervical lymph node metastasis in OSCC.

Impact of lymph node metastasis on the pattern of failure and survival in oral carcinomas

BACKGROUND Carcinomas of the oral cavity present a high risk for neck metastases that decrease the disease control and survival. METHODS A total of 106 patients with squamous cell carcinoma of the oral cavity who had metastatic neck nodes were studied. The impact of neck metastasis and treatment modalities on outcome was assessed. RESULTS Thirty-eight patients developed neck recurrence or distant metastasis. The 5-year survival, neck recurrence-free, and distant metastases-free rates were 56%, 84%, and 77%, respectively. Univariate analyses showed extranodal spread (ENS), number of positive nodes, and adjuvant chemotherapy were predictors for survival. In multivariate analysis, ENS and postoperative radiotherapy were of borderline significance. There was no prognostic factor for neck control. The presence of ENS and lower levels of positive nodes and no chemotherapy were associated with high distant failure rates. CONCLUSIONS To prevent distant metastases, patients with ENS should be considered for adjuvant chemotherapy.

Evaluation of histopathologic parameters in predicting cervical lymph node metastasis of oral and oropharyngeal carcinomas

A retrospective study of 53 patients with squamous cell carcinomas of the oral cavity and oropharynx was undertaken to evaluate histopathologic parameters in predicting cervical lymph node metastasis. Biopsy and surgical specimens were examined for degree of differentiation, pattern and depth of stromal invasion, lymphatic-vascular invasion, and lymphoplasmacytic response in relation to metastasis. The incidence of lymph node metastasis in tumors showing grade III type diffuse invasion (71.4%) and with stromal invasion of more than 8 mm in depth (83.3%) was significantly higher than that of tumors with well-demarcated boundaries (44.4% to 5.2%) and superficial invasion (35.3% to 8.3%). Lymph node metastasis also increased in the presence of lymphatic-vascular invasion by tumor cells, whereas the degree of differentiation and lymphoplasmacytic response was not related to metastasis. Thus, the pattern and the depth of stromal invasion and the presence of lymphatic-vascular invasion were important indicators in prediction of cervical lymph node metastasis. Prophylactic neck dissection is advocated when grade III type diffuse invasion, invasion exceeding 8 mm in depth, or grade II type invasion accompanied by a 4 mm to 8 mm depth of invasion is observed in a biopsy specimen.

Predicting factors for distant metastases in head and neck carcinomas : An analysis of 103 patients with locoregional control

PURPOSE This study evaluated the ability of certain clinical and pathologic parameters to predict distant metastases (DMs) in patients with squamous cell carcinoma of the head and neck. MATERIALS AND METHODS A total of 103 patients with histologically proven squamous cell carcinoma of the head and neck were studied. None had persistent or recurrent disease above the clavicle. Of these patients, 48 (47%) had metastatic lymph nodes. The relationships of tumor stage, primary site, clinical growth pattern, tumor differentiation, regional node status, and extranodal spread (ENS) with DMs were evaluated. RESULTS Twenty-one (20%) of the 103 patients developed DMs as the initial treatment failure. The incidence of DMs was significantly higher in patients with neck metastases (40%) than in those without neck metastases (4%) (P < .001). The degree of histologic differentiation and the presence of ENS were also correlated with the subsequent occurrence of DMs. There was no statistical difference in the incidence of DMs based on sex, location, stage of the disease, and clinical growth pattern. On multivariate analysis, only pathologic nodal status and ENS proved to be independent cofactors of DMs. The most common site of DMs was the lungs (56%), followed by bone (16%) and skin (16%). CONCLUSION The presence of pathologically positive nodes is the most critical factor to influence the eventual development of DMs.

Emergence of keratin 17 vs. loss of keratin 13: Their reciprocal immunohistochemical profiles in oral carcinoma in situ

To evaluate differential expressions for keratin (K) subtypes 13 and 17 in oral borderline malignancies, we examined 67 surgical specimens of the oral mucosa for their immunohistochemical profiles. From those specimens, 173 foci of epithelial dysplasia, 152 foci of carcinoma in situ (CIS), and 82 foci of squamous cell carcinoma (SCC) were selected according to our diagnostic criteria, along with 20 areas of normal epithelia. In normal epithelia, there was no K17 positivity (0%), whereas definite K13 positivity (100%) was observed. The same tendencies were obtained in mild (undefined) and moderate (true) epithelial dysplasias (K17: 0%; K13: 100%). In contrast, all CIS (100%) had K17 positivities, while K13 positivities were lost in many of them (7%). Similar tendencies were confirmed in invasive SCC (K17: 100%, K13: 4%). Simultaneous immunopositivities for K17 and K13 were found only in SCC (7%) and CIS (4%) foci with distinct keratinization. These foci also showed K10 positivities, though K10 positive areas were not identical to K13 positive areas. The results indicate that expressions of K17 and K13 are reciprocal in oral epithelial lesions and that the K17 emergence is related to malignancies.

Enhanced Expression of Podoplanin in Oral Carcinomas in situ and Squamous Cell Carcinomas

Objective: Podoplanin, a known lymphatic endothelial cell marker, has been reported to be expressed in various types of cancer. To elucidate the expression of podoplanin in precancerous lesions, we examined the immunohistochemical profiles of podoplanin in oral squamous epithelial lesions. Method: We studied a total of 298 foci of squamous cell carcinoma (SCC), carcinoma in situ (CIS), epithelial dysplasia, and hyperplastic and/or normal epithelial lesions by immunohistochemistry using D2-40. Results: There was no positivity for podoplanin in normal or hyperplastic epithelia, while all of the CIS and SCC foci stained positive. Approximately one third of the mild dysplasia foci (10 of 36 foci, 28%) and 80% of moderate dysplasia foci (78/98) showed grade 1 positive reactions (positive only in the 1st layer). Grade 2 reactions (up to 4th layer) were seen in 4 of 98 moderate dysplasia foci (4%), 29 of 74 CIS foci (39%), and 3 of 30 SCC foci (10%). Grade 3 reactions (to more than 5th layer) were found in 35 (47%) CIS foci and 26 (87%) SCC foci. Conclusions: The relationship between the present histological categorization and podoplanin grade was statistically significant. D2-40 expression is considered to be related to the severity of oral precancerous lesions.

Diagnostic value of integrin α3, β4, and β5 gene expression levels for the clinical outcome of tongue squamous cell carcinoma†

The objective of the current study was to identify biomarkers that reflect the clinical course of squamous cell carcinoma of the tongue (TSCC).

Micromechanics/structure relationships in the human mandible.

OBJECTIVES A clear understanding of the relationship between the micromechanical properties and orientation of the osteons within the mandible is important to understand mandibular function, fracture repair, treatment of temporo-mandibular joint disorders, the materials and organization of dental implants. The objective of this research was to obtain the micromechanical properties of human mandibular cortical bone as a function of orientation from TMJ to TMJ. METHODS A mandible obtained from a deceased 66 year-old female free of bone disease was used. The mandible was embedded in polymethylmethacrylate. The micromechanical properties analysis was obtained using the UH3 scanning acoustic microscope (SAM; Olympus Co., Tokyo, Japan). The coordinates system is defined such that the inferior border of mandibular is positioned on the x-y plane. x is along the anterior-posterior direction, y is in the horizontal direction and z is in superior-inferior direction. RESULTS The osteonal orientations were almost parallel to the x axis and eventually branched into two directions towards the coronoid process and condylar head. The SAM revealed that almost the whole area of the mandible body was found to be transversely isotropic in the plane perpendicular to the x axis. In the parallel and oblique directions, all data were transversely isotropic with respect to the x axis. Data of the perpendicular osteons were transversely isotropic with respect to the z axis. SIGNIFICANCE Having actual micromechanical properties as a function of orientation in the mandible could provide base line data for: fracture repair; choice of bone replacement materials.

Squamous Cell Carcinomas of the Mandibular Alveolus: Analysis of Prognostic Factors

Background: To assess the effect of clinicopathologic factors on local tumor control and survival in patients with mandibular alveolar carcinoma. Methods: Fifty patients with mandibular alveolar carcinoma treated surgically were included in this study. There were 3 patients with T1, 25 with T2, 5 with T3, and 17 with T4 disease. Clinical evidence of bone invasion was noted in 47 patients. A hemi- or segmental mandibulectomy was performed on 37 patients, whereas 10 patients had a marginal mandibulectomy. The impact of clinicopathologic variables on local tumor control and patient survival was assessed by univariate analysis. Variables included T and N stage, dental extraction, treatment modality, tumor differentiation, nodal status, surgical margin, and bone invasion. Results: Eleven patients (22%) develop recurrent disease, including 8 local recurrences, 1 neck, and 2 distant metastases. Overall, the 5-year actuarial rates of local control and disease-specific survival were 85 and 73%, respectively. Most local recurrences after surgical treatment were caused by inadequate resection margins. When resection margins were negative, the survival and local control rate were significantly better than when there were positive resection margins (survival, 91 vs. 11%; local control, 100 vs. 49%; p < 0.01). Neither T and N stages, clinical stage, tumor differentiation, dental extraction, bone invasion, extent of bone resection, nor treatment modality influenced outcome. Conclusions: The status of surgical margins was of major importance for the outcome of patients with gingival carcinoma of the mandible.

The impact of extranodal spread of lymph node metastases in patients with oral cancer

A retrospective study of 61 patients with histologically confirmed lymph node metastases was undertaken to evaluate the prognostic significance of extranodal spread (ENS) of metastases on the patterns of treatment failure and survival. ENS was present in 28 (46%) of the 61 patients and it was significantly associated with N stage. T stage, clinical stage, number of positive nodes, level of metastases, mode of treatment, and histological differentiation, however, did not influence the incidence of ENS. The 5-year disease-specific survival rate was 57%. The values for patients with and without ENS were 40% and 72%, respectively, which were statistically significant. The univariate analysis showed that the presence of ENS was a significant predictor of patient survival (P = 0.008). The number and level of positive nodes and postoperative radiotherapy had no prognostic importance. ENS, however, was also associated with an increased risk of distant metastases.