BACKGROUND Primary malignant melanoma of the esophagus (PMME) is a rare disease with a poor prognosis. There are few reports of early-stage cases in which tumor invasion reached the lamina propria or muscularis mucosae, as in the present case. A standard treatment for early-stage PMME has not yet been established. The present study aimed to summarize previous reports and to discuss the indicati...

In this study, we reported the first PEComa arising within the cervix with TFE3 gene rearrangement and aggressive biological behavior. Morphologically, the tumor showed infiltrative growth into the surrounding parenchyma. The majority of tumor cells were arrayed in sheets, alveolar structures, or nests separated by delicate fibrovascular septa. There was marked intratumoral hemorrhage, necrosis...

The clear cell variant of hepatocellular carcinoma is a rare entity, occurring at a frequency of less than 10% of hepatocellular carcinoma, with a female prevalence and usually associated with hepatitis C and cirrhosis. We reported a case of primary clear cell hepatocellular carcinoma occurring in a non-cirrhotic liver without history of hepatitis. Our examination included gross pathology, hist...

Adenoid cystic carcinoma (ACC) in the skin is very rare; only about 60 cases have been reported. Herein presented is a case of pigmented ACC arising from epidermis of the ear skin. An 85-year-old man presented black tumor of the right ear. Dermatologists' diagnosis was basal cell carcinoma (BCC). Large biopsy was obtained. The biopsy showed proliferation of atypical basaloid cells arranged in a...

Metastatic malignant melanoma has a wide spectrum of histopathologic patterns and often lacks melanin pigment. Without a known primary tumor, the diagnosis of metastatic malignant melanoma relies on a combination of morphology and immunohistochemical profile. Infrequently, commonly used markers for melanoma (S100, HMB45, Melan-A and Tyrosinase A) are negative. These cases pose critical diagnost...

In this study, we systematically explored the clinical manifestations, diagnosis, treatment, and prognosis of renal epithelioid angiomyolipoma (EAML) retrospectively by analyzing data of 52 patients diagnosed with EAML at four centers. Our results showed that the onset of EAML was usually inconspicuous, and so no obvious symptoms or signs had occurred in most patients at diagnosis. Its diagnose...

This study evaluated frequency-dependent effects of extremely low frequency electromagnetic fields (ELF-EMFs) on melanogenesis by melanocytes in vitro. Melanocytes were exposed to 2 mT EMFs at 30-75 Hz for 3 days before melanogenesis was examined. Exposure to ELF-EMFs at 50 and 60 Hz induced melanogenic maturation without cell damage, without changing cell proliferation and mitochondrial activi...

Hyalinizing clear cell carcinoma (HCCC) is very rare in the oral cavity, arising more frequently in the minor salivary glands. We present the case of a 57-year-old woman with a swelling on the anterior palatoglossal arch of 2x1 cm size. An incisional biopsy was taken and histological examination revealed typical clear cells arranged in anastomosing trabeculae, cords, nests, and solid sheets wit...

BACKGROUND Changes in the clinical appearance of benign dermal nevi during pregnancy may be concerning for malignant transformation. Because the hormonal milieu of pregnancy has not proven to alter their banal behavior, histologic characterization is needed to prevent over-diagnosis and unnecessary treatment. METHODS Dermal nevi excised from pregnant women (n = 16) were compared with nevi fro...

Primary sarcomatoid squamous cell carcinoma (S-SCC) of pharynx is a very rare tumor. A 77-year-old woman presented with sore throat. Laryngoscope revealed an infiltrating tumor of lower pharynx. The tumor was ulcerated and measured 3 cm × 4 cm × 3 cm. The tumor was invasive and involved the surrounding tissues. Biopsies showed sarcomatous malignant spindle cell proliferation as well as invasive...