TITLE:
Case Report: Asymptomatic Osteosarcoma
AUTHORS:
Reiko Yamaguchi, Seiichi Matsumoto, Keisuke Ae, Taisuke Tanizawa, Tabu Gokita, Keiko Hayakawa, Yuki Funauchi, Munehisa Kito, Hirotada Ishii, Noriko Motoi
KEYWORDS:
Incidental Osteosarcoma, Asymptomatic Osteosarcoma, De Novo Osteosarcoma
JOURNAL NAME:
Case Reports in Clinical Medicine,
Vol.4 No.12,
December
25,
2015
ABSTRACT: Osteosarcomas are primary malignant tumors that are characterized by the production of osteoid or immature bone. However they are the most common primary malignant tumor of bone in adolescents and young adults, the diagnosis of osteosarcoma is often delayed. It is because of the rarity of population, the variety of findings, nonspecific symptoms and so on. A 46-year-old male patient had left knee pain for 3 months without any symptoms in his right knee. At a nearby clinic, X-ray of his healthy side was taken by chance. The irregular bone formation was however seen in the metaphysis of the distal femur with spreading into the soft tissues. No abnormal findings were pointed out at his left side knee. A diagnosis of pleomorphic sarcoma was made by incisional biopsy. Pulmonary CT showed multiple nodules which were considered as multiple lung metastases. He was diagnosed as right femoral sarcoma, clinical stage IV (T1N0M1a) by TNM classification. He underwent preoperative chemotherapy, followed by limb-saving operation. No preoperative complaints were found in his left knee. Final diagnosis of surgically resected specimen was osteoblastic osteosarcoma which showed neoplastic osteoid formation within pleomorphic malignant cells. However, osteosarcomas occurred in adult populations are sometimes occurred as a secondary neoplasms, he had a history of diabetes but no other medical history, such as radiation therapy for a solid cancer, Paget’s disease, other benign bone lesions or inherited conditions. As far as our knowledge, we believe that this is a first case report of asymptomatic incidental osteosarcoma.