Recurrence of solitary fibrous tumors: Size matters (as does location)
Recent data suggest significant late metastatic capacity of solitary fibrous tumors (SFTs), contradicting previous records that suggested they are clinically indolent, warn surgeons at the Memorial Sloan Kettering Cancer Center in New York. The aim of the present study was to define prognostic factors for recurrence and disease-specific death (DSD) in resected primary SFTs. The results show that patients with large (≥ 8 cm) tumors in the chest or abdominal/retroperitoneal cavity are at greatest risk.
The authors analyzed data from 219 patients with resected primary SFTs, the median follow-up was 6.1 years. The 5- and 10-year cumulative DSD was 9 and 11 percent, respectively. The following showed a significant association with DSD: tumor size > median 8 cm, location, and complete gross resection. Local recurrence (LR) was associated with location and tumor size, and distant recurrence (DR) was associated with size. Both malignant and benign tumors had a capacity for DR and associated death. Tumors in the thoracic cavity and abdomen/retroperitoneum were associated with a 16 percent and 27 percent 10-year cumulative risk, respectively, and therefore presented the greatest risk of DR. A size ≥ 8 cm and tumor location in chest or abdominal/retroperitoneal cavity had a significant impact on DSD (hazard ratio 2.89 and 2.68, respectively).
Recurrence is “highly associated with DSD and events occur as late as 16 years after initial presentation”, including patients with tumors that were initially classified as benign, stress the authors.