The prognosis of patients with primary osteosarcoma who have undergone unplanned therapy.

Objective: For diagnosing osteosarcoma correctly, a combination of clinical, radiological and histological examinations is required. Erroneous treatment may cause local contamination and systemic seeding in patients. The purpose of this study was to compare outcomes of planned and unplanned treatment for osteosarcoma.

Methods: A retrospective review of patients with high-grade osteosarcoma who received appropriate surgical treatment and chemotherapy (n = 134) and those who were misdiagnosed and received unplanned surgery (n = 16) between July 1995 and February 2005.

Results: Patients who received unplanned treatment were older (mean age: 29.7 vs. 19.7 years; P = 0.003) and had a smaller mean tumor volume (119 vs. 280 ml; P = 0.015). The 5-year survival rate was not statistically different between the groups. Patients who had unplanned treatment had a higher local recurrence rate (43.8 vs. 17.9%; P = 0.024) and a shorter mean time for recurrence (11.9 vs. 20.8 months; P = 0.036). Furthermore, in patients who underwent unplanned treatment, lung metastases occurred earlier (6.1 vs. 16.2 months P = 0.021) and the final limb salvage rate was less (68.7 vs. 87.3%; P < 0.001).

Conclusions: Unplanned treatment for high-grade osteosarcoma can result in failure of local control and earlier systemic metastases.