537P - The impact of treatment-free interval on patient outcome after pulmonary metastasectomy for sarcoma

Background

Pulmonary metastasectomy is a commonly performed operation, but with inconclusive evidence for effectiveness. The aim of this study is to investigate the patient outcome after pulmonary metastasectomy in sarcoma patients with pulmonary metastases.

Methods

We retrospectively reviewed patients undergoing pulmonary metastasectomy for metastatic soft tissue and bone sarcomas in a single center. Treatment-free interval (TFI) was defined as the duration from the last date of primary tumor treatment to pulmonary metastasectomy. Recurrence-free interval (RFI), defined as the time from pulmonary metastasectomy to identification of new pulmonary metastasis, was calculated to determine freedom from lung recurrence. Post-metastasectomy survival (PMS) was defined as the time from pulmonary metastasectomy to death. Kaplan-Meier plots and Log-rank test were used to identify prognostic factors.

Results

Data of 102 patients were include in the analysis. In the RFI analysis, 77.4% patients (79/102) developed new pulmonary metastasis after pulmonary metastasectomy, with a median duration of 8.9 months. The 2-year freedom from lung recurrence was 23.6% and 51.9% in patients with TFI less than 12 months and TFI more than 12 months, respectively (p = 0.040). In the PMS analysis, the extrathoracic recurrence (p = 0.004) and TFI, but not primary site tumor recurrence, were significant prognostic factors. The 2 and 5-year PMS rates were 68.5% and 38.1%, respectively, in patients in patients with TFI less than 12 months, compared to 80.3% and 67.6%, respectively, in patients with TFI more than 12 months (p = 0.028).

Conclusions

A significant proportion (77.4%) of patients developed lung recurrences after pulmonary metastasectomy for sarcoma. Patients with TFI more than 12 months were associated with higher rate of freedom from lung recurrence and better PMS after pulmonary metastasectomy for sarcoma.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The author.

Funding

Has not received any funding.

Disclosure

The author has declared no conflicts of interest.