Abstract
Background
The active surveillance (AS) has been suggested for the initial treatment of extra-abdominal desmoid fibromatosis (EADF), the percentage of patients who shifted to invasive secondary treatments was significant. Tranilast, an anti-keloid medication, is frequently used in Japan, but there is no detailed report on its efficacy.
Methods
We retrospectively analyzed the medical records of EADF patients treated with tranilast between January 2009 and March 2021. Since EADF has been reported to shrink spontaneously, the effects of all drugs should be compared to AS. Therefore, we compared its clinical course with that under AS (determined by a systematic review) to assess the effect of tranilast. A systematic literature review of AS outcomes was conducted on July 22, 2021, according to PRISMA guidelines. The primary endpoint was the rate of conversion to secondary treatment. Secondary endpoints were progression-free survival, objective response rate (ORR), disease control rate (DCR), and adverse events. The rates of conversion to secondary treatment, ORRs, and DCRs were compared between the two groups using the Fisher's exact test.
Results
Eighteen patients who received tranilast as the initial treatment for EADF were included. Two patients (11.1%) underwent surgical resection due to tumor growth and continuous pain. Compared to the secondary treatment conversion rate from the pure AS approach (40.1%), tranilast was shown to significantly reduce the rate (p = 0.01). The ORR and DCR did not different between the two groups.
Conclusions
As initial treatment for EADF, tranilast is preferred over AS.
