Prognosis

In a review of 33 patients (3 were younger than 18 years) with low-grade fibromyxoid sarcoma, 21 patients developed a local recurrence after intervals of up to 15 years (median, 3.5 years). Fifteen patients developed metastases up to 45 years (median, 5 years) from diagnosis, most commonly to the lungs and pleura. This finding emphasizes the need for continued follow-up of these patients.[103] Even after metastases occur, the disease course may be indolent.[109]

In another report, 14 of 73 patients were younger than 18 years. In this series with a relatively short follow-up (median of 24 months), only 8 of 54 patients with adequate follow-up developed local (9%) or distant (6%) disease recurrence. This report suggested that the behavior of this tumor might be significantly better than previously reported.[110] However, because late metastases can occur, careful monitoring of these patients is warranted.

A study by the Ultra-Rare Sarcoma Working Group examined 32 patients with rare occurrences of distant metastases (20 with metastases at diagnosis, 12 after initial resection). Most metastases occurred in the lungs. Treatments varied, and minimal responses were observed to anthracycline-based and gemcitabine-based regimens with trabectidin. However, there were few patients in each treatment group.[111]