Local control of extra-abdominal desmoid tumours: Systematic review and metaanalysis

Background: The local control of desmoid tumours constitutes a continuing treatment dilemma due to its high recurrence rates. The purpose of this systematic review was to critically examine the current treatment of these rare tumors and to specifically evaluate the local failure and response rates of surgery, radiation and systemic therapy. Methods: We comprehensively searched the literature for relevant studies across CINAHL, EMBASE, MEDLINE and the Cochrane databases. Articles were categorized as surgery, radiation, surgery + radiation and systemic therapy (including cytotoxic and non cytotoxic). Methodological quality of included studies was assessed using the Newcastle-Ottawa Scale. Pooled odd ratios (OR) for comparative studies and weighted proportions with 95% confidence intervals are reported. Results: Thirty-five articles were included in the final analysis. Weighted mean local failure rates were 22% (95% CI [16-28%]), 35% (95% CI [26-44%]) and 28% (95% CI [18-39%]) for radiation alone, surgery alone and surgery + radiation respectively. In the analysis of comparative studies, surgery and radiation in combination had lower local failure rates than radiation alone (OR 0.7 [0.4, 1.2]) and surgery alone (OR 0.7 [0.4, 1.0]) Weighted mean stable disease rates were 91% (95% CI [85-96%]) and 52% (95% CI [38-65%]) for non cytotoxic and cytotoxic chemotherapy respectively. Conclusion: The current evidence suggests that surgery alone has a consistently high rate of local recurrence in managing extra-abdominal desmoid tumors. Radiation therapy in combination with surgery improves local control rates. However, the limited data on systemic therapy for this rare tumor suggests the benefit of using both cytotoxic and non cytotoxic chemotherapy to achieve stable disease.