Salamanca Javier, Dhimes Patricia, Pinedo Fernando, Gómez de la Fuente Enrique, Pérez Espejo Gustavo, Martínez-Tello Francisco José
Department of Pathology, Fundación Hospital de Alcorcón, Madrid, Spain.
J Cutan Pathol. 2008 Feb;35(2):231-5. doi: 10.1111/j.1600-0560.2007.00785.x.
Extraskeletal osteosarcoma is an uncommon neoplasm that usually arises in the deep soft tissues, especially in the lower extremities, with rare cases involving the subcutis or dermis. We report a 60-year-old man with an enlarging cutaneous mass in the right lower thigh. An incisional skin biopsy showed a well-defined, but non-encapsulated neoplasm, characterized by extensive cartilage with marked cellularity, atypia and high mitotic activity, involving the dermis and subcutis. Although osteoid or bone was not observed, a diagnosis of cutaneous chondroblastic osteosarcoma was suggested after excluding an origin in bone or other primary tumor sites by imaging techniques. Histopathologic features of the surgical specimen were characteristic, with a predominant high-grade chondroid component together with focal fibrosarcomatous zones, areas of multinucleated giant cells and foci of bone and osteoid formation. The patient underwent postoperative chemotherapy and is currently alive with pulmonary metastases 15 months after surgery. In summary, we report a unique case of cutaneous osteosarcoma of the chondroblastic subtype, diagnosed on incisional skin biopsy despite the absence of osteoid or bone during tumor sampling. As a rule, when an obviously malignant 'chondrosarcoma' is identified, one should always consider this entity.
骨外骨肉瘤是一种罕见的肿瘤，通常发生于深部软组织，尤其是下肢，累及皮下组织或真皮的病例罕见。我们报告一名60岁男性，其右大腿下部有一逐渐增大的皮肤肿物。切开皮肤活检显示为边界清楚但无包膜的肿瘤，其特征为大量软骨组织，细胞丰富、异型性明显且有高有丝分裂活性，累及真皮和皮下组织。尽管未观察到骨样组织或骨，但通过影像学技术排除了肿瘤起源于骨或其他原发肿瘤部位后，提示诊断为皮肤软骨母细胞性骨肉瘤。手术标本的组织病理学特征具有特异性，主要为高级别软骨样成分，伴有局灶性纤维肉瘤样区域、多核巨细胞区域以及骨和骨样组织形成灶。患者接受了术后化疗，目前术后15个月仍存活，伴有肺转移。总之，我们报告了一例独特的软骨母细胞亚型皮肤骨肉瘤病例，尽管在肿瘤取材时未发现骨样组织或骨，但通过切开皮肤活检得以诊断。通常，当确诊为明显恶性的“软骨肉瘤”时，应始终考虑到这种实体。
