PRIMARY OSTEOSARCOMA DISTAL FEMUR;
Objectives: This study was designed to estimate the incidence rate of pulmonary metastasis at the time of diagnosis ofprimary osteosarcoma distal femur in a tertiary care hospital. Study Design: Descriptive case series. Setting and Duration: OrthopaedicSurgery Unit, Mardan Medical Complex Teaching hospital, Bacha Khan Medical College, Mardan, KPK, Pakistan from March 2011 toSeptember 2012. Methodology: Nine patients of primary osteosarcoma distal femur were assessed with CT chest for pulmonarymetastasis. The frequency and patterns of pulmonary metastasis on CT chest were documented. After the biopsy reports all patientswere referred for neo adjuvant chemotherapy before any definite surgical procedure. The histological types of osteosarcoma were noted.RESULTS: Nine patients including 7 male (77.7%) and 2 females (22.2%) with mean age 12.4 years were included in our study. 66.6 %(n=6, 5 males, 1 female) had pulmonary metastasis on CT chest at initial presentation while 33 %( n=3,2 males,1 female) had nopulmonary metastases on CT chest. Three (50%) patients had pulmonary metastasis in the right lung, 1(16.6%) had on left side while2(33.3%) had bilateral pulmonary involvement. Of the cases with metastases at diagnosis, 55.5% had osteoblastic histology ofosteosarcoma compared with 33.3% of those with non metastatic disease. Conclusions: Majority of osteosarcoma distal femurpresented with pulmonary metastasis at initial presentation. A high index of suspicion accompanied by careful examination of the limband appropriate radiographs at initial assessment may reduce the incidence of such delays in diagnosis and the associated risks.