Background: Aggressive fibromatosis (AF) comprises tumors with a varying biological behavior. Genetic tumor characteristics may be predictive of recurrence; hence, the prognostic value of three specific mutations on the CTNNB1 gene was evaluated in relation to known clinicopathologic risk factors in patients with primary, sporadic AF. Methods: In a multi-institutional retrospective cohort study of patients with primary extra-abdominal and abdominal wall AF who underwent surgical treatment, the original pathology specimens were reviewed for the presence of a T41A, S45F, and 45P mutations on the CTNNB1 gene. For these mutations, the risk of recurrence was analyzed by the Kaplan–Meier method with log-rank test. Univariable and multivariable Cox regression was performed to calculate hazard ratios. Results: A total of 101 patients were analyzed. During a median follow-up of 41 months, 17 recurrences were detected; the cumulative 5-year recurrence rate was 22.8 %. A specific CTNNB1 mutation was found in 76 patients, with the majority of patients having a T41A mutation (n = 49). CTNNB1 mutations were associated with the risk of recurrence: the presence of a S45F mutation was associated with a 5-year cumulative risk of recurrence of 63.8 % (P < 0.001). Multivariable analysis showed that young age and S45F mutation were independent risk factors (P = 0.011 and P < 0.001). Conclusions: The presence of specific CTNNB1 mutations was predictive for recurrence in patients after surgical treatment for primary, sporadic extra-abdominal and abdominal AF. A S45F mutation increased the risk of recurrence significantly.,
Annals of Surgical Oncology
Erasmus MC: University Medical Center Rotterdam

van Broekhoven, D., Verhoef, K., Grunhagen, D. J., van Gorp, J., den Bakker, M., Hinrichs, J. W. J., … van Dalen, T. (2015). Prognostic Value of CTNNB1 Gene Mutation in Primary Sporadic Aggressive Fibromatosis. Annals of Surgical Oncology, 22(5), 1464–1470. doi:10.1245/s10434-014-4156-x