Research Center "The Great Senescence", Senescence, Urological, and Neurological Sciences Department, University of Catania, Catania, Italy.
Eur Rev Med Pharmacol Sci. 2012 Jul;16(7):977-82.
Extraskeletal osteosarcoma (ESOS) is a rare malignant mesenchymal neoplasm that accounts for less than 4% of all osteosarcomas and approximately 1-2% of all soft tissue sarcomas. The tumor is typically located in the deep soft tissues, without attachment to skeletal bones. Although ESOS has been found todevelop virtually in every organ, its most common locations are the limbs. In the case of abdominal or pelvic lesions the diagnosis can be very difficult, thus it necessarily requires confirmation after exploratory laparotomy and histopathology. Such tumors may reach enormous sizes before detection because the enlarging mass may not be associated with pain. ESOS may be one of the differential diagnoses to be considered in the case of calcified masses arising in retroperitoneal space. Here we describe a bulky, bilateral, metastatic ESOS arising from the retroperitoneum and causing obstructive uropathy with consequent hydronephrosis.
骨外骨肉瘤（ESOS）是一种罕见的恶性间叶性肿瘤，占所有骨肉瘤的比例不到 4%，约占所有软组织肉瘤的 1-2%。肿瘤通常位于深部软组织，与骨骼无附着。尽管 ESOS 几乎可以在每个器官中发生，但最常见的部位是四肢。对于腹部或骨盆病变，诊断可能非常困难，因此在剖腹探查和组织病理学检查后需要确认。由于增大的肿块可能不伴有疼痛，因此在检测之前，此类肿瘤可能会生长到巨大的尺寸。在考虑腹膜后间隙出现钙化肿块的鉴别诊断时，ESOS 可能是其中之一。在这里，我们描述了一例源自腹膜后并引起尿路梗阻性肾积水的巨大双侧转移性 ESOS。
