Evaluation of expression of genes CADM1, TWIST1 and CDH1 by immunohistochemestry in melanocytic lesions.

AIM: Malignant melanoma is an aggressive disease and its incidence is increasing worldwide. Genetic predisposition and exposure to environmental factors, especially sunlight, are risk factors. Histopathologic distinction between nevi and melanomas can be difficult. It is anticipated that the evaluation of the immunohistochemical expression of some genes could contribute to the differential diagnosis of questionable histologically lesions. The objective of this study was to investigate wether the evaluation of the immunohistochemical expression of genes CADM1, TWIST1 and CDH1 (E-cadherin), that take part in mechanisms of cell adhesion and epithelial-mesenchymal transition, contributes to the differential diagnosis of melanocytic lesions difficult to diagnose. MATERIALS AND METHODS: Retrospective cross-sectional study based on immunohistochemistry analysis of samples of 30 dysplastic compound melanocytic nevi, 30 melanomas less than 1.0mm thick and 30 melanomas more than 1.0mm thick, diagnosed between 2013 and 2016. A score was used to evaluate color intensity and percentage of cells stained. RESULT: There were significant reductions in the expression of the genes CADM1 and CDH1 in melanomas (below and above 1.00mm of thickness) and in melanomas more than 1.0mm thick, respectively, compared to dysplastic compund melanocytic nevi. There was also lower expression of the genes CADM1 and CDH1 in melanomas greater than 1.0mm thick compared to melanomas less than 1.0mm. The gene TWIST1 showed no significant difference in expression between groups. CONCLUSION: These findings allow us to conclude that the immunohistochemical expression of CADM1 has the potential to contribute as an auxiliary tool to the differential diagnosis between nevi and melanomas.

Pemphigus vulgaris of the cervix: diagnostic difficulties associated with the Pap test.

Pemphigus vulgaris (PV) is a rare mucocutaneous disease caused by the abnormal production of antibodies against epithelial cell surface glycoproteins, resulting in loss of cell adhesion and intraepithelial blister formation. Cervical involvement in PV has been poorly reported, and there is little information regarding the criteria about consequential cytological changes identified in a Papanicolaou-stained cervicovaginal smear (Pap smear). Here, we report a case of PV manifesting in the cervix as well as the difficulty associated with the cytomorphological identification and interpretation of acantholytic cells. This case involved a 40-year-old patient with no history of Pap test abnormalities and no prior diagnosis of PV. In the cytological assessment, cells were identified both in isolation and in clusters that exhibited round nuclei of increased volume, inconspicuous nucleoli, and perinuclear halos. The patient underwent a cervical biopsy that revealed vesiculobullous lesions and morphological pattern consistent with PV. A skin biopsy confirmed this diagnosis. We concluded that knowledge of PV cytomorphology is important because difficulties associated with the identification and interpretation of acantholytic cells might be responsible for false positive diagnoses of cervical neoplasia. However, a suspected diagnosis of PV is possible if the cytological findings are carefully correlated with the clinical data.