Junichi Asaumi

Odontogenic myxoma of maxillary sinus: CT and MR–pathologic correlation

We showed the characteristic features of odontogenic myxoma in the maxillary sinus with computed tomography (CT), magnetic resonance imaging (MRI), and histopathological findings. CT images showed a multilocular soft tissue mass with bone destruction and thinning, and the characteristic finding of this lesion as strands of fine lacelike density. MRI revealed intermediate signal intensity on T1-weighted image and high signal intensity on T2-weighted image. MRI showed the erosive extent of the lesion into the adjacent structures. In contrast T1-weighted image, the peripheral portion of the lesion with a relatively large quantity of collagen bundles was enhanced, while the central portion with only mucoid component was not. The CT and MRI appearances correlated well with the histologic features and therefore were considered to be a useful tool for diagnosis of myxoma.

MR imaging of nasopalatine duct cysts

We describe the magnetic resonance (MR) features of two cases of nasopalatine duct cyst (NPDC), including the first presentation of T1-weighted images (WI). The signal intensity of the cases of NPDC showed homogeneous high signal intensity on both on T1 and T2WI, although most cysts of maxillofacial regions demonstrate low to intermediate signal intensity on T1WI. NPDC may commonly be of high signal intensity on T1WI, which is consistent with keratin and viscous fluids.

CT and MR imaging of localized amyloidosis.

The localized form of amyloidosis affecting the head and neck region is rare. The characteristic features of localized amyloidosis appeared as multiple nodules on the tongue, lip, and cheek on computed tomography (CT) and magnetic resonance imaging (MRI). Contrast-enhanced CT scans represented this lesion as a marked nodular enhancement. MR features of this lesion appeared slightly low on T1-weighted images and slightly high on T2-weighted images compared with T1-T2 images of residual normal tongue. Time contrast intensity curves obtained from dynamic MRI rapidly increased to reach a plateau and gradually decreased during the late and delayed phases. MR findings suggest that such lesions might be comprised of fibrous tissue with abundant vessels. This report suggests that dynamic MRI might be helpful for diagnosing localized amyloidosis.

A Case of Unerupted Lower Primary Second Molar Associated with Compound Odontoma

Odontoma is the most common type of benign odontogenic tumor, and often causes disturbances in the eruption of its associated tooth. Odontomas usually occur in the permanent dentition, and rarely occur solely in the primary dentition. This case report documents a six-year-old-child with a compound odontoma located in the mandible, which caused the impaction of the primary second molar.

A spindle cell carcinoma presenting with osseous metaplasia in the gingiva: a case report with immunohistochemical analysis

BackgroundSpindle cell carcinoma (SpCC) is a rare, high malignant variant of squamous cell carcinoma (SCC), which shows biphasic proliferation of conventional SCC component and malignant spindle shape cells with sarcomatous appearance.MethodsA case of Spindle cell carcinoma with bone-like calcified materials, occurring at the mandibular molar region of 71-years-old Japanese male patient was presented with gross finding, histological findings and MRI image. To identify the characteristics of the bone-like materials, immunohistochemistry were performed.ResultsHistologically, the cancer cells were composed of spindle cells and epithelial cells which form nests with prominent keratinization. Histological findings showed typical histology of the SpCC, however, as an uncommon finding, spatters of calcified, bone-like materials were observed in between the cancer cells. Immunohistochemistry revealed that cancer cells were positive for cytokeratins and vimentin to a varying degree and negative for Desmin, S-100, Osteopontin, BMP-2 or BMP-4. These findings implied that the calcified materials were formed by metaplasia of the stromal cells.DiscussionBone-like materials formation by osseous and/or cartilaginous metaplasia of the stroma in the carcinoma has been reported. However, the detailed mechanism of these metaplasia and affection on the clinical feature, prognosis and therapies are not well established. In summary, we presented an unique case of SpCC, which has not been described in the literature.

Optimal contouring of seminal vesicle for definitive radiotherapy of localized prostate cancer: comparison between EORTC prostate cancer radiotherapy guideline, RTOG0815 protocol and actual anatomy

BackgroundIntermediate- to-high-risk prostate cancer can locally invade seminal vesicle (SV). It is recommended that anatomic proximal 1-cm to 2-cm SV be included in the clinical target volume (CTV) for definitive radiotherapy based on pathology studies. However, it remains unclear whether the pathology indicated SV extent is included into the CTV defined by current guidelines. The purpose of this study is to compare the volume of proximal SV included in CTV defined by EORTC prostate cancer radiotherapy guideline and RTOG0815 protocol with the actual anatomic volume.MethodsRadiotherapy planning CT images from 114 patients with intermediate- (36.8%) or high-risk (63.2%) prostate cancer were reconstructed with 1-mm-thick sections. The starting and ending points of SV and the cross sections of SV at 1-cm and 2-cm from the starting point were determined using 3D-view. Maximum (D1H, D2H) and minimum (D1L, D2L) vertical distance from these cross sections to the starting point were measured. Then, CTV of proximal SV defined by actual anatomy, EORTC guideline and RTOG0815 protocol were contoured and compared (paired t test).ResultsMedian length of D1H, D1L, D2H and D2L was 10.8 mm, 2.1 mm, 17.6 mm and 8.8 mm (95th percentile: 13.5mm, 5.0mm, 21.5mm and 13.5mm, respectively). For intermediate-risk patients, the proximal 1-cm SV CTV defined by EORTC guideline and RTOG0815 protocol inadequately included the anatomic proximal 1-cm SV in 62.3% (71/114) and 71.0% (81/114) cases, respectively. While for high-risk patients, the proximal 2-cm SV CTV defined by EORTC guideline inadequately included the anatomic proximal 2-cm SV in 17.5% (20/114) cases.ConclusionsSV involvement indicated by pathology studies was not completely included in the CTV defined by current guidelines. Delineation of proximal 1.4 cm and 2.2 cm SV in axial plane may be adequate to include the anatomic proximal 1-cm and 2-cm SV. However, part of SV may be over-contoured.

A modified Phase I trial of radiation dose escalation in 3D conformal radiation therapy with concurrent vinorelbine and carboplatin chemotherapy for non-small-cell lung cancer

The Radiation Therapy Oncology Group reported a maximum tolerated dose of 74 Gy for patients with non-small cell lung cancer (NSCLC); however, it was unclear whether this dose could be safely administered to Asian patients due to differences in their physique compared to Western patients. We therefore conducted a modified Phase I trial to determine whether 70 Gy could be safely delivered to Chinese patients with NSCLC undergoing 3D-conformal radiation therapy (3D-CRT) with concurrent chemotherapy. Previously untreated NSCLC patients received 3D-CRT (2 Gy/day, 5 fractions per week). Three dose levels were examined: 62, 66 and 70 Gy. Two cycles of concurrent chemotherapy (vinorelbine and carboplatin) were started on the first day of radiation therapy. Dose-limiting toxicity (DLT) was defined as severe or life-threatening side effects that altered the continued implementation of chemoradiotherapy. Among the 19 patients recruited in this study, most of the haematologic and non-haematologic toxicities were mild to moderate and clinically manageable. Only one patient, in the 70 Gy cohort, experienced a DLT of Grade 3 radiation-induced pneumonia. The overall response rate was 77.8% (14/18). The median progression-free survival (PFS) was 12 months, and the 1-year PFS was 37.6%. Our results support both the feasibility of incorporating 3D-CRT with concurrent vinorelbine and carboplatin and a dose escalation to 70 Gy for Chinese patients with NSCLC, based on the acceptable toxicity and encouraging overall response and survival rates. A further evaluation of this regimen in a prospective Phase II trial is ongoing.

Analysis of Magnetic Resonance Images of Disk Positions and Deformities in 1,265 Patients with Temporomandibular Disorder

Objectives To compare MRI manifestations according to gender and age and to identify correlations between clinical manifestations and MRI findings in patients with temporomandibular disorder (TMD) as based on a large series. Materials and Methods Fat suppressed oblique sagittal images of the open and closed mouth were acquired, and MRI scanning parameters were applied. Results The patients consisted of 946 females (average, 36.6 years old), and 319 males (average, 34.3 years old). In all TMD patients, 945 had symptoms in the unilateral temporomandibular joint (TMJ) and 320 in the bilateral TMJ. There were significant differences in the distribution of disk positions based on age, regardless of gender, in the unilaterally and bilaterally symptomatic groups; however, the results were not significant in the asymptomatic group. There were significant differences with respect to the distribution of disk positions between males and females in asymptomatic group and in the unilaterally symptomatic group, although the bilaterally symptomatic group did not show significant differences in this regard. As regards the disk positions in the joints of the three groups (asymptomatic group, unilaterally and bilaterally symptomatic groups), there were significant interactive effects of disk positions, regardless of gender. There were statistically significant age-related differences in disk deformities in all symptom groups, regardless of gender, except for in the group of males lacking symptoms in either joint. As regards disk deformities among the three groups studies here, there were significant interactive effects for disk positions, regardless of gender.

Effects of PKC inhibitors on suppression of thermotolerance development in tsAF8 cells

EŒects of protein kinase C (PKC) inhibitors (H7, staurosporine, calphostin C) on thermotolerance development were investigated in temperature sensitive tsAF8 cells derived from Syrian hamster BHK21 cells. Cells were pre-heated at 458C for 20 min, incubated at 348C with PKC inhibitors for varying lengths of time, i.e. 1.25± 10.0 h, and then heated at 458C for 30 min. Increasing survival fractions after the second heat treatment was inhibited by the treatment with H7 (40± 160 mM), with staurosporine (0.05± 1.0 mM), and with calphostin C (0.8, 1.2 mM) in a concentration dependent manner. When the concentrations of these PKC inhibitors were low, the restraint of increasing survival fractions was temporary, since survival fractions increased 3± 7.5 h after pre-heating. However, the survival fractions were almost constant by the treatment with 160 mM H7 and 1.0 mM staurosporine. Induction of HSP72 after heat stress was investigated in tsAF8 and BHK21 cells. Cells were heated at 458C for 20 min and incubated at 34 or 39.78C (tsAF8), at 378C (BHK21). Intensity of intracellular ̄ uorescence from HSP72 was measured by ̄ ow cytometry. HSP72 was induced in BHK21 cells, but there was no de® nite induction of HSP72 in tsAF8 cells at either 39.7 or 348C. These results suggest that PKC is related with the thermotolerance development in tsAF8 cells; however, HSP72 is not involved in the thermotolerance development in tsAF8 cells.Effects of protein kinase C (PKC) inhibitors (H7, staurosporine, calphostin C) on thermotolerance development were investigated in temperature sensitive tsAF8 cells derived from Syrian hamster BHK21 cells. Cells were pre-heated at 45 degrees C for 20 min, incubated at 34 degrees C with PKC inhibitors for varying lengths of time, i.e. 1.25-10.0 h, and then heated at 45 degrees C for 30 min. Increasing survival fractions after the second heat treatment was inhibited by the treatment with H7 (40-160 microM), with staurosporine (0.05-1.0 microM), and with calphostin C (0.8, 1.2 microM) in a concentration dependent manner. When the concentrations of these PKC inhibitors were low, the restraint of increasing survival fractions was temporary, since survival fractions increased 3-7.5 h after pre-heating. However, the survival fractions were almost constant by the treatment with 160 microM H7 and 1.0 microM staurosporine. Induction of HSP72 after heat stress was investigated in tsAF8 and BHK21 cells. Cells were heated at 45 degrees C for 20 min and incubated at 34 or 39.7 degrees C (tsAF8), at 37 degrees C (BHK21). Intensity of intracellular fluorescence from HSP72 was measured by flow cytometry. HSP72 was induced in BHK21 cells, but there was no definite induction of HSP72 in tsAF8 cells at either 39.7 or 34 degrees C. These results suggest that PKC is related with the thermotolerance development in tsAF8 cells; however, HSP72 is not involved in the thermotolerance development in tsAF8 cells.

Comparison of the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths.

Purpose The aim of this study was to assess and compare the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths. Materials and Methods A total of 40 patients (20 cases and 20 controls) were included in this retrospective study. Cases were defined as subjects with a submandibular sialolith confirmed by computed tomography (CT), whereas controls did not have any submandibular calcifications. Three observers with different expertise levels assessed panoramic and occlusal radiographs of all subjects for the presence of sialoliths. Intraobserver and interobserver agreement were assessed using the kappa test. Sensitivity, specificity, accuracy, positive and negative predictive values, and the diagnostic odds ratio of panoramic and occlusal radiographs in screening for submandibular sialoliths were calculated for each observer. Results The sensitivity and specificity values for occlusal and panoramic radiographs all ranged from 80% to 100%. The lowest values of sensitivity and specificity observed among the observers were 82.6% and 80%, respectively (P=0.001). Intraobserver and interobserver agreement were higher for occlusal radiographs than for panoramic radiographs, although panoramic radiographs demonstrated a higher overall accuracy. Conclusion Both panoramic and occlusal radiographic techniques displayed satisfactory diagnostic performance and should be considered before using a CT scan to detect submandibular sialoliths.