Yong Koo Park

Oncogenic Osteomalacia Caused by a Phosphaturic Mesenchymal Tumor of the Oral Cavity: A Case Report

We report a case of oncogenic osteomalacia associated with a phosphaturic mesenchymal tumor in a 31-year-old woman. She was presented with severe generalized bone and muscle pain and was restricted to bed. She lost 20cm in height over the 8 years since she had first noticed a pain in her thigh. A walnut-sized, hard, soft tissue tumor was found very easily beside her lower molar teeth. Radiologic examination revealed a remarkable decrease in bone density and multiple pathologic fractures of spine, femur and phalangeal bones. Severe hypophosphatemia, hyperphosphaturia, low plasma 1,25-dihydroxyvitamin D3 level and high plasma PTH level were disclosed at presentation. Histomorphometric examination revealed an extensive area of unmineralized osteoid and little mineralizing activity. A pharmacologic dose of 1α-hydroxyvitamin D3 or 1,25-dihydroxyvitamin D3 slightly increased the serum phosphate level and renal tubular reabsorption of phosphate, and slightly decreased plasma PTH level without any symptomatic improvement. Histologic examination of the tumor revealed a mixed connective tissue tumor that consisted of central woveh bones and surrounding primitive spindle cells with prominent vascularities. After removal of the tumor, all biochemical, hormonal and radiologic abnormalities disappeared with remarkable symptomatic improvement.

Microarray‑based DNA methylation study of Ewing's sarcoma of the bone

Alterations in DNA methylation patterns are a hallmark of malignancy. However, the majority of epigenetic studies of Ewing’s sarcoma have focused on the analysis of only a few candidate genes. Comprehensive studies are thus lacking and are required. The aim of the present study was to identify novel methylation markers in Ewing’s sarcoma using microarray analysis. The current study reports the microarray-based DNA methylation study of 1,505 CpG sites of 807 cancer-related genes from 69 Ewing’s sarcoma samples. The Illumina GoldenGate Methylation Cancer Panel I microarray was used, and with the appropriate controls (n=14), a total of 92 hypermethylated genes were identified in the Ewing’s sarcoma samples. The majority of the hypermethylated genes were associated with cell adhesion, cell regulation, development and signal transduction. The overall methylation mean values were compared between patients who survived and those that did not. The overall methylation mean was significantly higher in the patients who did not survive (0.25±0.03) than in those who did (0.22±0.05) (P=0.0322). However, the overall methylation mean was not found to significantly correlate with age, gender or tumor location. GDF10, OSM, APC and HOXA11 were the most significant differentially-methylated genes, however, their methylation levels were not found to significantly correlate with the survival rate. The DNA methylation profile of Ewing’s sarcoma was characterized and 92 genes that were significantly hypermethylated were detected. A trend towards a more aggressive behavior was identified in the methylated group. The results of this study indicated that methylation may be significant in the development of Ewing’s sarcoma.

Type and Incidence of Soft Tissue Sarcomas in Korea: 2001-2007

Malignant melanoma involving the ovary is uncommon. Most of the reported ovarian malignant melanomas are metastatic, and only 44 cases are primary. Teratoid elements must be identified in the ovary for the diagnosis of primary malignant melanoma because ovaries normally do not contain melaninproducing cells. However, it is challenging to assess the primary site of ovarian malignant melanoma because it is almost always found in an advanced state, replacing entire ovarian structures, and this makes it difficult to determine whether the lesion is a primary ovarian melanoma. Mature cystic teratoma is the most common benign germ cell tumor of the ovary, and it constitutes 15-25% of ovarian tumors overall. A wide variety of malignant tumors may arise within a mature cystic teratoma, including squamous cell carcinoma (75%), adenocarcinoma (7%), undifferentiated carcinoma, basal cell carcinoma, and various sarcomas (7%). Malignant melanoma arising from mature cystic teratoma has also been reported, but it is very rare. Here, we report on an uncommon case of primary malignant melanoma arising from a mature ovarian cystic teratoma with multiple metastatic lesions.