MR appearance of a rare ameloblastic fibroma with formation of dental hard tissues with histopathologic correlation: a case report.

An ameloblastic fibroma with formation of dental hard tissues, which the classical name is ameloblastic fibro-odontoma (AFO), is a rare type of mixed odontogenic tumor. An 8-year-old boy was diagnosed with AFO, with an inhomogeneous high signal within the lesion shown by T2-weighted magnetic resonance imaging (MRI). Computed tomography (CT) imaging revealed a unilocular low CT value area of 24 × 19 × 26 mm with buccolingual bony expansion and cortical bone thinning on the left side of the mandible including the crown of the mandibular left second molar. In addition, multiple calcified bodies were detected within the lesion, one of which had a CT value of approximately 2200 HU, equivalent to that of enamel. MRI indicated the lesion to be sized 24 × 19 × 25 mm along with buccolingual bony expansion in the left side of the mandible. Additionally, the lesion showed an internal inhomogeneous high signal, while a portion had an especially high signal in T2-weighted images. That particularly high signal area coincided with the nodular growth area of mucus-rich mesenchymal components without the epithelial component in histopathology findings. The particularly high signal revealed by T2-weighted imaging could be attributed to the mucus-rich component. MRI was found useful for revealing differences in the internal histopathological properties of an AFO in our patient.

Radiation-induced undifferentiated spindle cell sarcoma following high-dose-rate interstitial brachytherapy for tongue squamous cell carcinoma.

High-dose-rate interstitial brachytherapy (HDR-ISBT) has recently come to be considered one of the most effective treatments for oral cancer. On the other hand, it is important to note that radiation therapy has some side effects. Especially, radiation-induced malignancy is probably the most serious complication affecting long-term survivors. We report a case of a radiation-induced undifferentiated spindle cell sarcoma that developed following HDR-ISBT for tongue squamous cell carcinoma (SCC). A 39-year-old woman with right tongue SCC underwent HDR-ISBT (60 Gy, 10 fractions, 8 days) treatment. Five years and one month later, a tumor had developed at the primary site. Surgery was performed for the tumor, which was histopathologically diagnosed as an undifferentiated spindle cell sarcoma. That was distinct from the squamous cell origin of the primary cancer. According to recently established criteria for radiation-induced malignancy, this case was classified as a radiation-induced sarcoma. A search of the literature revealed no previous report of radiation-induced malignancy following HDR-ISBT for tongue cancer.

Multiple orthokeratinized odontogenic cysts: clinical, pathological, and genetic characteristics.

BACKGROUND: Orthokeratinized odontogenic cyst (OOC) is a rare developmental odontogenic cyst of the jaw. It was originally believed to be a variant of odontogenic keratocyst (OKC) but is now considered to be a distinct entity. OOC usually presents as a single lesion and recurs infrequently. On the other hand, OKC often presents with multiple lesions and displays locally aggressive behavior and a high recurrence rate associated with the protein patched homolog 1 (PTCH1) gene mutation. Multiple OOC cases are extremely rare and seem to be aggressive, but their pathogenesis is not fully understood. This study aimed to determine the clinical, pathological, and genetic characteristics of multiple OCC. METHODS: Three cases of multiple OOC were evaluated for clinical and histological findings, and immunohistochemical expression of Ki-67 and Bcl-2. Furthermore, PTCH1 mutations were analyzed by next-generation sequencing using a custom panel to cover the entire exon of PTCH1. RESULTS: The three cases of multiple OOC included two men and one woman with a mean age of 25.3 years old (range, 18-38 years old). Each case had two or three OOCs (total of seven OOCs), all of which were simultaneously detected. Of the seven OOCs that manifested as multiple jaw cysts, seven (100%) occurred in the posterior regions, four (57.1%) occurred in the mandible, and four (57.1%) were associated with an impacted tooth. Histological examination revealed cysts lined by orthokeratinized stratified squamous epithelium. Immunohistochemistry showed a low Ki-67 labeling index and no Bcl-2 expression in the seven OOCs. No pathogenic PTCH1 mutations were detected in any of the seven OOCs. None of the patients had any other symptoms or signs of recurrence at the last follow-up (6-60 months). CONCLUSION: Multiple OOCs appeared to occur more often in younger patients than solitary OOC. Both multiple and solitary OOCs may be related diseases within the entity of odontogenic cysts. Multiple OOCs are clinicopathologically and genetically distinct from OKC.

TUBB3 immunostaining improves the diagnostic accuracy of oral liquid-based cytology in squamous cell carcinoma.

OBJECTIVE: Although class III beta-tubulin (TUBB3) is not expressed in normal epithelium, its expression in cancers of some organs has been reported. Herein, we investigated the expression pattern and expression levels of TUBB3 in oral squamous cell carcinoma (SCC), and assessed whether TUBB3 immunostaining could improve the diagnostic accuracy of oral scraping liquid-based cytology (LBC). METHODS: Paraffin sections of biopsies from 107 patients with primary SCC and 30 patients with squamous papilloma of the tongue or gingiva were immunostained for TUBB3. In addition, 15 LBC samples obtained from the study participants with SCC were immunostained for TUBB3. Seven LBC samples were false-negative. The TUBB3 expression level in each sample was evaluated and classified as 3+, 2+, 1+, or 0. RESULTS: TUBB3 expression was confirmed in 91.6% of paraffin-embedded SCC specimens. Clear and diffuse positivity (2+ or above) was observed in 77.6% of the total cases. In the well-differentiated type, tumour cells in the middle layer of the parenchyma specifically expressed TUBB3. In almost LBC samples, cancerous intermediate cells showed immunopositivity similar to that of paraffin samples, even if cellular atypia was not clear in Papanicolaou staining. CONCLUSIONS: TUBB3 immunostaining is useful for diagnosing oral SCC in scraping LBC, especially when samples consist of intermediate cells with little morphological change. Moreover, TUBB3 immunostaining could improve the diagnostic accuracy of oral scraping LBC by reducing false-negatives.

Clear Cell Carcinoma in the Oral Cavity with Three Novel Types of EWSR1-ATF1 Translocation: A Case Report.

Clear cell carcinoma (CCC) is a rare epithelial malignant tumor of the salivary glands. It is characterized by tumor cells with clear cytoplasm, hyalinized stroma, and most importantly the fusion genes EWSR1-ATF1, EWSR1-CREM, and EWSR1-PLAG1. Break-apart FISH has been performed for multiple CCC cases, but direct sequencing analysis has been performed in relatively few. Herein, we report an interesting case of CCC harboring three EWSR1-ATF1 translocations: EWSR1 exon 8-ATF1 exon 4, EWSR1 exon 7-ATF1 exon 4, and EWSR1 exon 7-ATF1 exon 5. This case indicates the possibility of independent EWSR1-ATF1 gene translocations, and could provide insight into CCC tumorgenesis.

Primary Alveolar Soft Part Sarcoma of Cheek: Report of a Case and Review of the Literature.

Alveolar soft part sarcoma (ASPS) is a rare soft tissue sarcoma characterized by an alveolar or organoid arrangement of polygonal tumour cells separated by fibrovascular septa. A specific fusion gene [ASPS critical region 1 (ASPSCR1)-TFE3] was detected in ASPS. Despite being a slow-growing tumour without pain and dysfunction, ASPS is characterized by early metastasis, which leads to poor prognosis. Herein, we report a rare case of primary ASPS of the cheek harbouring ASPSCR1 (exon 7)-TFE3 (exon 5) fusion gene in a 21 year-old woman. This tumour was a well-circumscribed, smooth, round mass that was clinically suspected as a benign tumour. However, histologically, it was observed that the polygonal tumour cells were arranged in solid and alveolar growth patterns. Post-operative examination of the whole body excluded the possibility of metastasis at other sites. Thus, careful immunohistochemical and genetic analyses, as well as whole-body examination, demonstrated that the tumour was a primary ASPS of the cheek.

Clear Cell Carcinoma of Palatal Minor Salivary Gland Harboring a Novel EWSR1-ATF1 Fusion Gene: Report of a Case and Review of the Literature.

Clear cell carcinoma (CCC) is a rare low-grade malignant salivary gland carcinoma. EWSR1-ATF1 fusion has been characterized as a consistent finding in CCC, with breakpoints described between EWSR1 exon 11 and ATF1 exon 3. So far, over 100 cases of CCC harboring EWSR1 rearrangement arising from salivary gland of the oral cavity have been reported. Although EWSR1 involvement in these cases was confirmed by EWSR1 break-apart FISH indicating the translocation, sequence analysis for EWSR1-ATF1 fusion type has been reported only in three cases of CCC so far. Herein, we report a CCC case with novel EWSR1-ATF1 fusion (EWSR1 exon 15 and ATF1 exon 5) arising in minor salivary gland and review the role of the chimeric variants in some malignancies with EWSR1-ATF1 rearrangement. Current tumor was composed of the small nests of clear tumor cells and hyalized fibrous stroma. Immunohistochemically, the tumor was positive for AE1/AE3, CK5/6 and p63, negative for S100, Melan-A, SMA and CD10. After 8 months of follow-up, there are no evidence of recurrence.

Galectin-1 expression is associated with tumour immunity and prognosis in gingival squamous cell carcinoma.

AIMS: Galectin-1 (Gal-1) is a ß-galactoside-binding protein that overexpresses in cancer and plays pivotal roles in tumour progression. Gal-1 regulates angiogenesis and invasiveness, and suppresses tumour immunity by inducing T cell apoptosis. Several studies have examined the relationship between Gal-1 and tumour immunosuppression in vivo, but they have not examined the clinicopathological relationship between Gal-1 expression and apoptotic T cell number in human tissue. In this study, we investigated the association between Gal-1 expression and apoptotic T cells of gingival squamous cell carcinoma (GSCC), as well as other clinicopathological factors. METHODS: Immunohistochemical investigation of 80 GSCC specimens using anti-Gal-1, anti-CD3, anti-CD4, anti-CD8, anti-CD34, antipodoplanin and anticleaved caspase-3 (CC-3) antibodies was performed. Relative expression levels of CD3 and CC-3, as well as CD8 and CC-3 were assessed simultaneously by double immunostaining. Gal-1 expression and T cell apoptosis were evaluated in 6 high-power fields (3 in the tumour and 3 in the stroma). RESULTS: Gal-1 expression in GSCC was significantly correlated with T cell infiltration (p=0.036), and apoptosis of CD3+ and CD8+ T cells (p<0.001). Moreover, Gal-1 expression was significantly correlated with lymph node metastasis (p=0.021), histological differentiation (p<0.001) and overall survival rate (p=0.021). CONCLUSIONS: These findings suggest that Gal-1 plays an important role in immune escape of GSCC cells, and Gal-1 expression level may be a useful clinicopathological prognostic marker for GSCC.

[A case of combined central and peripheral demyelination].

A 22-year-old man had had difficulty running fast since about he was 10 years old. In June 2011, he was referred to us because of worsened unsteady gait. A neurological examination revealed mild ataxic speech, weakness of the four limbs, with spasticity, and pes cavus. Magnetic resonance T2-weighted images showed multiple high-intensity lesions in the bilateral periventricular white matter, brainstem, and thoracic spinal cord. Peripheral nerve conduction studies revealed marked motor conduction velocities were markedly reduced and sensory nerve velocities were not evoked in the upper and lower limbs. A sural nerve biopsy showed highly active demyelinating lesions. The patient was treated with high-dose steroid therapy (intravenous methylprednisolone, 1,000 mg/day × 3 days) followed by self-injection of interferon ß. With these treatments, his symptoms gradually improved. In this case, we could not detect the causative factors, and all autoantibodies tested, except for the anti-neurofascin antibody, were negative. The anti-neurofascin antibody might induce demyelination in the central and peripheral nervous systems. However, in the literature, the evidence of an association between this antibody and these clinical characteristics is not conclusive. We need more studies on the pathogenesis of combined central and peripheral demyelination to establish more effective therapies.

[A case of bilateral auricular chondritis with anti-glutamate receptor (GluRε2) antibody-positive non-herpetic acute limbic encephalitis].

A 62-year-old man experienced pain and swelling in both of his auricles. One and a half months later, he was referred to us because of a memory disturbance. A neurological examination revealed disorientation and recent memory impairment. Diffusion-weighted and fluid-attenuated inversion recovery magnetic resonance images showed high intensity and swelling lesions in the bilateral medial temporal regions. In cerebrospinal fluid, mononuclear cell counts and total protein concentration were increased, but a herpes polymerase chain reaction was negative. Thus, he was suspected to have non-herpetic acute limbic encephalitis (NHALE). In addition, relapsing polychondritis (RP) was suspected because of the bilateral auricular chondritis and type-II collagen antibody positivity in the serum. He was treated with high-dose steroid therapy (two cycles of intravenous methylprednisolone, 500 mg per day for 3 days), which was followed by oral steroid therapy. With these treatments, his symptoms, including the painful auricular swelling and memory disturbance, gradually improved. This case exhibited anti-glutamate receptor (GluRε2) antibody positivity in both serum and cerebrospinal fluid, but anti-N-methyl-D-aspartate glutamate receptor antibody (NR1 + NR2) by cell-based assay negative in cerebrospinal fluid. Although a vascular mechanism of NHALE that is associated with RP has been suggested in the literature, this autoantibody might have induced NHALE as the mechanism of neuronal damage to target neuron in our case. More studies on the pathogenesis of NHALE that is associated with RP are needed.

Anti-neurofascin antibody in patients with combined central and peripheral demyelination.

OBJECTIVES: We aimed to identify the target antigens for combined central and peripheral demyelination (CCPD). METHODS: We screened target antigens by immunohistochemistry and immunoblotting using peripheral nerve tissues to identify target antigens recognized by serum antibodies from selected CCPD and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) cases. We then measured the level of antibody to the relevant antigen in 7 patients with CCPD, 16 patients with CIDP, 20 patients with multiple sclerosis, 20 patients with Guillain-Barré syndrome, 21 patients with other neuropathies, and 23 healthy controls (HC) by ELISA and cell-based assays using HEK293 cells. RESULTS: At the initial screening, sera from 2 patients with CCPD showed cross-like binding to sciatic nerve sections at fixed intervals, with nearly perfect colocalization with neurofascin immunostaining at the node and paranode. ELISA with recombinant neurofascin revealed significantly higher mean optical density values in the CCPD group than in other disease groups and HC. Anti-neurofascin antibody positivity rates were 86% in patients with CCPD, 10% in patients with multiple sclerosis, 25% in patients with CIDP, 15% in patients with Guillain-Barré syndrome, and 0% in patients with other neuropathies and HC. The cell-based assay detected serum anti-neurofascin antibody in 5 of 7 patients with CCPD; all others were negative. CSF samples examined from 2 patients with CCPD were both positive. In anti-neurofascin antibody-positive CCPD patients, including those with a limited response to corticosteroids, IV immunoglobulin or plasma exchange alleviated the symptoms. CONCLUSION: Anti-neurofascin antibody is frequently present in patients with CCPD. Recognition of this antibody may be important, because patients with CCPD who are antibody positive respond well to IV immunoglobulin or plasma exchange.

Intercellular adhesion molecule-1 (ICAM-1) expression correlates with oral cancer progression and induces macrophage/cancer cell adhesion.

Intercellular adhesion molecule-1 (ICAM-1) is a transmembrane glycoprotein in the immunoglobulin superfamily, which plays an important role in cell adhesion and signal transduction. Although ICAM-1 is believed to play a role in several malignancies, it is still uncertain whether or not ICAM-1 expression contributes to cancer progression. In this study, we performed clinicopathological and cell biological analyses of ICAM-1 expression in oral squamous cell carcinoma (SCC). First, we examined the ICAM-1 expression in tongue SCC immunohistochemically, and revealed that ICAM-1 was expressed predominantly at the invasive front area of tongue SCC. ICAM-1 expression at the invasive front area was correlated with invasion, lymph node metastasis and increased blood and lymphatic vessel density of the tongue SCC. The relationship between ICAM-1 expression and clinicopathological factors were consistent with the increased proliferation, invasion and cytokine-production activities of ICAM-1-transfected SCC cells. Second, we analyzed the relationship between macrophages and ICAM-1-expressing tongue SCC cells because ICAM-1 is known to act as a ligand for adhesion of immune cells. Increased ICAM-1 expression in tongue SCC was correlated with increased macrophage infiltration within SCC nests. Moreover, macrophage/SCC-cell adhesion through ICAM-1 molecule was revealed using an in vitro cell adhesion and blockade assay. These findings indicate that ICAM-1 plays an important role in tongue SCC progression, which may result from the SCC-cell activity, angiogenic activity, lymphangiogenic activity and macrophage/SCC-cell adhesion.

Neural hyperplasia in maxillary bone of multiple endocrine neoplasia type 2B patient.

Multiple endocrine neoplasia (MEN) type 2B is the rarest and most aggressive form of MEN syndrome. MEN 2B patients manifest characteristic oral and facial features besides the neural crest cell-derived tumors, including medullary carcinoma, pheochromocytoma, mucosal neuroma, and ganglioneuromatosis of the gut. We report a case of MEN 2B diagnosed on the basis of the warning signs of mucosal neuroma and multiple neural hyperplasias in the maxillary bone resected during orthognathic surgery. A subsequent systemic examination under the pathologic diagnosis of neural lesions revealed medullary thyroid carcinoma, megacolon, thickened corneal nerves, and RET gene mutation, thus verifying the diagnosis of MEN 2B. An immunohistochemical study revealed an increased number of unmyelinated Schwann cells in the hyperplastic nerves. We suggest that intraosseous neural hyperplasia is a specific finding of the MEN 2B syndrome in addition to the known oral and facial manifestations.

[Neuromyelitis optica with syndrome of inappropriate secretion of antidiuretic hormone and hypersomnia associated with bilateral hypothalamic lesions: a case report].

A 31-year-old woman with a 5-year history of recurrent optic neuritis and encephalomyelitis underwent repeated steroid therapy. She developed general malaise and fever in October 2009. Laboratory tests revealed marked reduction in serum Na (106 mEq/L). Because the plasma osmotic pressure was lower than the urinary osmotic pressure and the serum antidiuretic hormone (ADH) level was elevated, she was diagnosed with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Magnetic resonance imaging (MRI) revealed high signal intensities on symmetrical T2 weighted and fluid attenuated inversion recovery (FLAIR) images of both sides of the hypothalamus. The serum samples tested positive for the antibody to aquaporin-4 (AQP4). Previously conducted cervical MRI had revealed a longitudinally extending lesion in the cervical cord, and brain MRI had revealed brainstem lesions. We diagnosed the patient with neuromyelitis optica (NMO) according to the revised diagnostic criteria for NMO proposed by Wingerchuk in 2006. Furthermore, she complained of excessive daytime sleepiness. The concentration of orexin in the cerebrospinal fluid was mildly reduced and the orexin levels returned to normal when her sleepiness decreased. ADH and orexin neurons localized in the hypothalamus; hence, we considered the above-mentioned symptoms to be caused by bilateral hypothalamic lesions.

Calcifying odontogenic cyst: radiologic findings in 11 cases.

OBJECTIVE: This retrospective study examines the relationship between histopathologically diagnosed cases of in calcifying odontogenic cysts (COCs) on the adjacent dentition. STUDY DESIGN: The records including diagnostic radiograph images of 11 patients treated for COCs from 1991 to 2004 were analyzed and correlations made between radiologic and histopathologic features. Special attention was applied to the associations between COCs and adjacent teeth. RESULTS: Radiologic and histopathologic features of the 11 lesions were variable, with some lesions being more solid and others more cystic. Calcifications varied from small flecks to solid calcified areas of frank odontoma. In 7 cases, the COC was associated with an impacted tooth and 5 of these cases involved COC-enveloping teeth. All cases excepting one in an edentulous jaw segment showed positional changes of adjacent teeth, including impaction. CONCLUSIONS: The radiographical features of COCs are varied but there is a high frequency of changes in adjacent teeth, including dental impaction. The presence of impaction or displacement of teeth for COCs occurring in the posterior segments of the jaw, and absence of this finding for anteriorly placed lesions may be indicative of the timing of COC development.

[Preoperative chemotherapy with TS-1 and low dose cisplatin for oral squamous cell carcinoma patients--a preliminary study].

We investigated the histological response and toxicities of combination chemotherapy with TS-1 and low-dose CDDP, and evaluated the usefulness of this regimen as a preoperative chemotherapy. Fourteen patients were enrolled in this study (two men and 12 women, with a mean age of 54.5 years). Patients were administered TS-1 80 mg/m2/day (days 1-14) and CDDP 5 mg/m2/day (days 1-5, 8-12) and followed by radical surgery or biopsy within 2 weeks. Ten patients completed 1 cycle of chemotherapy, two received 0.5 cycle and two others 1.5 cycle. The histological antitumor effects were evaluated with Ohboshi & Shimosato's classification using surgical or biopsy specimens of primary tumors. The response rate was 64.3% in clinical evaluation and 50.0% in histological evaluation. The number of patients who showed CR were 7/14 (50.0%) and 5/14 (35.7%) by histological and clinical evaluation, respectively. Two patients showed grade 3 neutropenia. Almost all patients revealed no or mild toxicities. TS-1 with low-dose CDDP represents a highly effective antitumor activity and mild toxicities. Especially, the CR rate was very high. These data suggested that this regimen was useful to avoid surgery or to realize minimal surgery for oral squamous cell carcinoma patients.

Morphological changes of regional lymph node in squamous cell carcinoma of the oral cavity.

BACKGROUND: Regional immune responses with various types of cancer have been studied histopathologically, however, the prognostic value remains conflicting. The aim of this study was to evaluate morphological changes related to lymph node metastasis and the prognostic value for oral cavity squamous cell carcinoma. METHODS: With histopathologic whole architecture of 430 lymph nodes, gross area, germinal center (GC) area, paracortical area (PA), and tumor area were measured. RESULTS: Metastatic node had significantly lower distribution ratio of PA to lymphoarea than that of tumor-free node. GC area was not constantly associated with lymph node metastasis. In Cox multivariate analysis, the mean ratio of PA to gross area/lymphoarea was an independent prognostic factor. CONCLUSIONS: The proportion of PA to gross/lymph area was associated with lymph node metastasis and long-term survival and may be useful in stratification of those patients for a requirement of adjuvant treatments.