Korean Journal of Pathology最新文献

Pigmented extramammary Paget's disease (PEMPD) is an uncommon intraepithelial adenocarcinoma and a rare variant of Paget's disease affecting skin that is rich in apocrine sweat glands such as the axilla, perianal region and vulva. It most commonly occurs in postmenopausal women and presents as a superficial pigmented scaly macule, mimicking a melanocytic lesion. The histological presentation is adenocarcinoma in situ with an increased number of melanocytes scattered between the Paget's cells. Therefore, PEMPD may be misdiagnosed as a melanocytic tumour both clinically and histologically. The tumour cells are usually positive for cytokeratin 7, epithelial membrane antigen, Cam 5.2, HER2, and mucicarmine stain while S100 and human melanoma black-45 highlight the processes of reactive dendritic cells. The association between Paget's cells and intratumoural reactive melanocytes is still unclear. We report our first case of PEMPD associated with an intradermal naevus involving the axilla in a 63-year-old woman.

This study reports a case of anaplastic transformation from a well-differentiated thyroid carcinoma in a young patient. The first recurrent tissue contained poorly differentiated foci that revealed lower thyroglobulin, thyroid transcription factor 1 (TTF-1), and galectin-3 expression than the well-differentiated area. However there was no increased p53 or Ki-67 expression in the poorly differentiated foci, nor in the well-differentiated area. The tissue subsequently relapsed and revealed only anaplastic features, complete loss of thyroglobulin, TTF-1, and galectin-3 expression and revealed an increase in p53 and Ki-67 expression. The BRAF V600E and BRAF V600V mutation were found in the initially diagnosed papillary thyroid carcinoma and the poorly differentiated foci of the recurring papillary thyroid carcinoma; however, only the BRAF V600V mutation was found in the anaplastic carcinoma. These results suggest that overexpression of p53 and Ki-67 contributed to the anaplastic transformation. We also found that the BRAF type changed during the tumor relapse.

Well-differentiated papillary mesothelioma is an uncommon tumor of the testes that usually presents as a hydrocele. Here, we present the case of one patient who did not have a history of asbestos exposure. The tumor was localized in the tunica vaginalis and was composed of three pedunculated masses macroscopically. Microscopically, branching papillary structures with focal coagulative necrosis were present. In addition to immunohistochemistry, simian virus 40 DNA was also tested by polymerase chain reaction. This report presents one case of this rare entity, its clinical and macroscopic features, and follow-up results.

This paper reports a case of low-grade adenosquamous carcinoma (LGASC) arising in a 69-year-old woman, who presented with a 1-cm palpable mass on her right breast. Core needle biopsy diagnosed the mass as a fibroadenoma. After six months, the mass increased in size, and the patient received subsequent mammotome excision. On microscopic examination, bland-looking small glands were infiltrating into the fibrotic stroma with lymphocytic infiltrates at the periphery. Hematoxylin and eosin staining revealed relatively easily detectable myoepithelial cells along the outside in each of the glandular structures with variable degrees of squamous metaplasia. Based on histologic features, the patient was diagnosed with LGASC. LGASC is a rare variant of metaplastic carcinoma, which is characterized by a favorable prognosis. Due to the bland cytology and presence of myoepithelial cells, LGASC can be misdiagnosed as benign lesion. Additionally, inconsistent expression of myoepithelial markers could aid the diagnosis of LGASC.