Chondrosarcoma (CS) is a malignant tumour of long and flat bone characterised by the formation of cartilage. Mesenchymal chondrosarcoma (MCS) is a rare subtype of CS that is more aggressive and may lead to erroneous diagnosis in a limited biopsy. The diagnosis is mainly based on the histopathological appearance of biphasic pattern of undifferentiated small round cells separated by islands of well-differentiated hyaline cartilage. We report a case of 13-year-old boy who initially presented with gum swelling and the biopsy result suggested a benign fibrous lesion. Following an extensive lesion shown in radiologic findings, the tumour excision was done and finally was diagnosed as an MCS of the maxilla. The patient was given postoperative chemotherapy (EURO-EWING 99 regimen), and now on regular follow-up for monitoring of local recurrence or tumour metastasis.
This work investigates the physicochemical characteristics of grease-trap wastewater discharged from a large community market. It proposes potential mechanisms of fat, oil, and grease (FOG) solid formation, separation, and accumulation inside grease traps. Sixty-four samples, i.e., the floated scum, suspended solid-liquid wastewater, and settled sludge, were collected from the grease-trap inlet and outlet chambers. A lower pH of 5-6 at 25-29 °C inside the grease trap than those reported under the sewer conditions (pH 6-7) was revealed. A significant difference in solid and dissolved constituents was also discovered between the inlet and outlet chambers, indicating that the baffle wall could affect the separation mechanism. The sludge samples had 1.5 times higher total solids (TS) than the scum samples, i.e., 0.225 vs. 0.149 g g-1 TS, revealing that the sludge amount impacted more significantly the grease trap capacity and operation and maintenance. In contrast, the scum samples had 1.4 times higher volatile solids (VS) than the sludge samples, i.e., 0.134 vs. 0.096 g g-1 VS, matching with the 64.2 vs. 29.7% of carbon content from CHN analysis. About 2/3 of the free fatty acids (FFAs) with palmitic acids were the primary saturated FFAs, while the remaining 1/3 of unsaturated FFAs were found in the solid and liquid samples. Although up to 0.511 g g-1 FOG can be extracted from the scum samples, none from the sludge samples. More diverse minerals/metals other than Na, Cl, and Ca were found in the sludge samples than in the scum samples. Grease-trap FOG solids and open drain samples exhibited similar physicochemical properties to those reported in the literature. Four potential mechanisms (crystallization, emulsification, saponification, and baffling) were presented. This work offers insights into the physicochemical properties of grease-trap wastewater that can help explore its FOG solid formation, separation, and accumulation mechanisms inside a grease trap.