Oral koilocytic dysplasia: long-term clinical control. A case report.

Leukoplakia, a common lesion in the oral cavity, is considered a premalignant lesion that can develop into carcinoma. In 1986, a group of pathologists described a variant of epithelial dysplasia and named it "koilocytic dysplasia" (KD). This article presents a case of KD that was identified for 12 years as "carcinoma in situ". Even after removal of the lesion, it recurred with no signs of malignancy. The histopathological findings revealed all of the signs of KD (koilocytosis, acanthosis, multinucleated keratinocytes and atypical mitoses). Liquid-based cytology and hybrid capture were performed to confirm the diagnosis. Despite a professional recommendation to have the lesion removed surgically, the patient chose periodic clinical control. The mechanism of HPV transmission in the oral cavity still remains partially unknown. Additional studies on this subject are required to better understand the role of HPV in cell transformation in the oral cavity.

Late diagnosis of a primary oral malignant melanoma: a case report.

Primary oral malignant melanoma (OMM) is a rare disease, representing 0.2% to 8% of all melanomas. Eighty percent of the cases are located on the palate and maxillary gingiva, with the remainder found on the mandibular gingiva, buccal mucosa, tongue, and floor of the mouth. OMM are highly aggressive with the tendency to metastasize and invade the surrounding tissues more readily than other oral malignancies. Prognosis is poor and the five-year survival rate ranges from 5% to 20%. The usual therapeutic approach for OMM is surgical excision of the primary tumor, supplemented by radiotherapy, with chemotherapy and immunotherapy serving as adjuvant. The authors report a well-documented case of OMM in a 40-year-old male who was referred to the Oral Medicine Service of the Cancer Hospital, Cuiabá, Mato Grosso, Brazil exhibiting a firm mass at the right side of the face. Palpation revealed a painless soft tissue arising in maxillary gingiva, extending to the palate and vestibular mucosa. Pigmented areas were found in the mass. The patient underestimated his symptoms and look for treatment after a substantial growth of the lesion. This is an example of how a delayed detection affects the prognosis of OMM. The patient was treated by radiotherapy since surgical intervention was not possible, but died seven months later.

Differential expression of galectin-3, beta-catenin, and cyclin D1 in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands.

BACKGROUND: Galectin-3 has been implicated in tumor progression of some malignancies as thyroid, prostate, and salivary gland tumors. Recently, it has been suggested that this protein may be an important mediator of the beta-catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, the present study aimed to correlate galectin-3 expression with beta-catenin and cyclin D1 expressions in adenoid cystic carcinoma (ACC) and in polymorphous low-grade adenocarcinoma (PLGA). METHODS: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of São Paulo and the proteins were analyzed by immunohistochemistry. RESULTS: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for beta-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC (P < 0.05). CONCLUSIONS: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although beta-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.

Metallothionein and p-Akt proteins in oral dysplasia and in oral squamous cell carcinoma: an immunohistochemical study.

BACKGROUND: Oral leukoplakia (OL) is the main potentially malignant lesion of the oral cavity, and oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Therefore, the aim of this study was to verify the immunoexpression of p-Akt and Metallothionein (MT) proteins in dysplasic and neoplasic oral lesions. METHODS: Immunohistochemical studies were carried out on 10 normal epithelium, 30 OL and 15 OSCC paraffin-embedded samples. Immunoperoxidase reaction for p-Akt and MT proteins was applied on the specimens, and the positivity of the reactions was calculated for 1000 epithelial cells. RESULTS: Using the ANOVA and the Tukey's post hoc statistical analyses, it was observed a significant difference in the immunoexpression for p-Akt and MT when the OSCC samples were compared with normal and dysplasic epithelial groups. In addition, the Pearson's correlation test showed a significant correlation between the proteins' expression. CONCLUSION: Based on the data obtained, p-Akt and MT activation may play an important role in the conversion of a potentially malignant oral lesion to a malignant carcinoma since its earlier stages.