A novel preoperative risk score to guide patient selection for resection of soft tissue sarcoma lung metastases: An analysis from the United States Sarcoma Collaborative.

Background: Surgical resection for sarcoma lung metastases has been associated with improved overall survival (OS).

Methods: Patients who underwent curative-intent resection of sarcoma lung metastases (2000-2016) were identified from the US Sarcoma Collaborative. Patients with extrapulmonary metastatic disease or R2 resections of primary tumor or metastases were excluded. Primary endpoint was OS.

Results: Three hundred and fifty-two patients met inclusion criteria. Location of primary tumor was truncal/extremity in 85% (n = 270) and retroperitoneal in 15% (n = 49). Forty-nine percent (n = 171) of patients had solitary and 51% (n = 180) had multiple lung metastasis. Median OS was 49 months; 5-year OS 42%. Age ≥55 (HR 1.77), retroperitoneal primary (HR 1.67), R1 resection of primary (HR 1.72), and multiple (≥2) lung metastases (HR 1.77) were associated with decreased OS(all p < 0.05). Assigning one point for each factor, we developed a risk score from 0 to 4. Patients were then divided into two risk groups: low (0-1 factor) and high (2-4 factors). The low-risk group (n = 159) had significantly better 5-year OS compared to the high-risk group (n = 108) (51% vs. 16%, p < 0.001).

Conclusion: We identified four characteristics that in aggregate portend a worse OS and created a novel prognostic risk score for patients with sarcoma lung metastases. Given that patients in the high-risk group have a projected OS of <20% at 5 years, this risk score, after external validation, will be an important tool to aid in preoperative counseling and consideration for multimodal therapy.