Yolk sac tumor of mouth floor / 华西口腔医学杂志

Yolk sac tumor (endodermal sinus tumor) is a malignant germ cell tumor which usually arise in gonads. It is rare occurring in the oral cavity. Here, a yolk sac tumor of mouth floor was reported and relevant literatures were reviewed.

Clinicopathologic and immunohistochemical study of 23 cases of mesenchymal chondrosarcoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic and immunohistochemical features of mesenchymal chondrosarcoma.</p><p><b>METHODS</b>The clinical and histologic features of 23 cases of mesenchymal chondrosarcoma were analyzed. Immunohistochemical study was also performed in 14 of the cases.</p><p><b>RESULTS</b>The age of patients ranged from 12 to 47 years. Fourteen of them occurred in males. Thirteen cases involved the bony skeleton and 5 cases affected the soft tissue. The patients presented with pain and/or swelling. Histologically, the tumor consisted of a mixture of undifferentiated small round cells and hyaline cartilage. Transition between the two components was demonstrated and growth plate-like cartilage was observed. Immunohistochemical study showed that the small round cells were positive for Sox9 (14/14), CD99 (12/14), vimentin (6/14), CD56 (4/14), CD57 (4/14), neuron-specific enolase (3/14) and desmin(1/14). They were negative for Coll-II, S-100 protein, epithelial membrane antigen, pan-cytokeratin, synaptophysin, chromogranin A, CD34 and c-erbB2.</p><p><b>CONCLUSIONS</b>Mesenchymal chondrosarcoma is a rare malignant tumor. Thorough histologic examination, when coupled with immunohistochemical findings, is helpful in arriving at a correct diagnosis.</p>

Role of ataxia telangiectasis mutated in the oncogenesis of oral squamous cell carcinoma / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the role of ataxia telangiectasis mutated (ATM) gene in the oncogenesis and progression of oral squamous cell carcinoma (OSCC).</p><p><b>METHODS</b>A total of 61 formalin-fixed and paraffin-embedded samples were obtained from patients with hyperkeratosis, oral leukoplakia, OSCC and normal healthy controls. The expression of ATM protein in all of the samples was investigated by streptavidin-peroxidase immunohistochemistry assay. PCR was also performed to detect the loss of heterozygosity (LOH) in D11s2179 of ATM gene. The correlations between ATM and the clinical and histopathological characteristics were also investigated.</p><p><b>RESULTS</b>The results indicated that the ATM expression was increased in oral premalignant lesions (P<0.05). For OSCC, 68.8% samples showed normal or increased ATM expression, while 31.3% had decreased or absent ATM expression. Significant differences were found between the group of decreased or absent ATM expression and that of normal or increased expression over the histopathological grade and lymph node metastasis state. PCR results displayed that none of the samples from oral premalignant lesions showed abnormal changes, while 3 of the OSCC (9.38%) showed loss of heterozygosity (LOH) and 2 (6.25%) with microsatellite instability (MSI). Those 3 samples of LOH showed absent ATM expression.</p><p><b>CONCLUSION</b>These findings indicated that the over expression of ATM may contribute to prevent carcinogenesis of OSCC. ATM inactivation may be one of the genetic alterations of the molecular progression of OSCC.</p>

Metastasizing pleomorphic adenoma of the submandibular gland: a case report / 华西口腔医学杂志

Metastasizing pleomorphic adenomas without histological evidence of malignancy have rarely been reported. A case of 30-year-old woman with a mass which showed a benign pleomorphic adenoma appearanced histologically in the left submandibular gland and right supercollarbone respectively was described. Eight years ago, the patient suffered from pleomorphic adenoma of the left submandibular gland. It revealed histopathologic features consistent with the recurrent and metastasizing tumor. The clinic pathological features, possible mechanism and prevention approach of metastasizing pleomorphic adenoma were discussed based on previously reports in the literature.

A case report on canceration of proliferative verrucous leukoplakia / 华西口腔医学杂志

Proliferative verrucous leukoplakia (PVL) is a particular form of oral leukoplakia clinically characterized by chronic proliferation, multiple occurrence, and intractability. It is seen mostly among elderly women and often involves bucca, palate, gingiva and tongue. Its canceration rate is very high. This article reports a case of a middle-aged woman with progressive PVL which became focally malignant who complained about buccal and palatal exophytic white patches, and discusses the possible pathogenic mechanism, diagnosis, treatment, prognosis of PVL and differentiation between PVL and other types of oral leukoplakia by way of reviewing relevant literature.

Epstein-Barr virus infection in benign lymphoepithelial lesions with malignant transformation of salivary glands / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To examine the role of Epstein-Barr virus (EBV) infection in benign lymphoepithelial lesions with malignant transformation of salivary glands.</p><p><b>METHODS</b>2 cases benign lymphoepithelial lesions with focal malignant transformation (BLEL-FMT), 14 cases of malignant lymphoepithelial lesion (MLEL) and 4 cases of benign lymphoepithelial lesion (BLEL) of salivary glands, 4 cases of nonspecific chronic sialadenitis were examined. Sections were cut from the paraffin blocks and performed in situ hybridization (ISH) for EBV encoded small RNA-1 (EBER-1) using 30-base synthesized oligonucleotide probe and polymerase chain reaction (PCR) for BamHI-W regein of EBV DNA (123 bp).</p><p><b>RESULTS</b>In ISH, strong signals for EBER-1 were obtained in most of epithelial cell nuclei in examined specimens of BLEL-FMT, no matter in benign or malignant areas and in all specimens of MLEL (14/14), PCR demonstrated a DNA fragment of 123 kbp in 2 cases of BLEL-FMT and 12 cases of MLEL (12/14). In contrast, there were no significant ISH/PCR signals in examined BLEL and nonspecific chronic sialadenitis.</p><p><b>CONCLUSIONS</b>A few cases of MLEL may arise from BLEL and EBV may plays an important role in the pathogenesis of BLEL-FMT of salivary glands.</p>