Local Therapy Strategies Appear Effective for Many Patients with Desmoid Tumors

Local therapy provides durable tumor control for a majority of patients with desmoid tumors, but young patients, patients with an extremity location, and patients with large tumors are at increased risk of recurrence, according to a recent study published in Cancer.

The patient cohort underwent local therapy with surgery alone, radiation therapy (RT) alone, or combined modality therapy (RT and surgery). These results showed that systemic therapy should be considered as a front-line option for this increased risk of recurrence population when active treatment is indicated.

“(Desmoid tumors) are clinically unpredictable and can cause significant morbidity,” wrote the researchers. “Local therapy consisting of surgery, RT, or surgery and RT provides durable (local control) in a majority of patients. However, young patients, patients with large tumors, and patients with extremity tumors are at increased risk of relapse.”

The data showed that local recurrence occurred in 127 patients (31%) at a median time of 21 months. More, the 5-year local control (LC) rate was 67% and overall median follow-up time for patients was 95 months.

As for the increased risk population, factors that were significantly associated with poorer 5-year LC included patients less than 30 years old (57% vs 75% for an age > 30 years; hazard ratio [HR], 1.73; P= .004), an extremity location (57% vs 71% for a nonextremity location; HR, 1.77; P= .004), and large tumors (59% for >10 cm [HR, 2.17; P= .004] and 65% for 5.1-10 cm [HR, 1.71; P= .02] vs 76% for ≤5 cm).

Further, analyzing this population revealed no local therapy strategy to be superior for patients less than 30 years old (HR for surgery, 1.42; P= .33; HR for RT, 1.36; P= .38) or for large tumors greater than 10 cm in size (HR for surgery, 1.55; P= .46; HR for RT, 0.91; P= .91). For patients with extremity tumors, surgery alone was associated with a worse LC rate (HR for surgery, 5.15; P< .001; HR for RT, 1.51; P= .38).

“Systemic therapy should be considered a first-line treatment in these high-risk subsets, but a prospective evaluation of this strategy is warranted,” wrote the researchers. “For patients with extremity tumors, surgery alone as local therapy may have inferior tumor control in comparison with strategies that include RT.”

This cross-sectional cohort study examined 412 patients with nonmesenteric desmoid tumors who received definitive local therapy consisting of surgery, RT, or combined modality therapy with surgery and RT at The University of Texas MD Anderson Cancer Center between 1965 and 2018.

The researchers included selection bias in the local therapies recommended to patients as one of the limitations for this study. More, the cohort was treated over an extensive period of time, introducing the potential for evolving diagnostic imaging and treatment standards to impact the results. Finally, extracting data to identify treatment decisions with modern paradigms was retrospectively was unreliable.

The researchers suggest that, moving forward, prospective multi-institutional studies are warranted to further evaluate treatment strategies. The study also adds that while patient age and tumor size should be evaluated to identify risk, local therapy should not be withheld in scenarios where tumor progression would prevent a future successful LC procedure.

“We evaluated one of the largest cohorts of patients with nonmesenteric (desmoid tumors) in the literature to investigate outcomes after local therapy and risk factors associated with poorer outcomes,” wrote the researchers. “Although the majority of patients achieved durable LC, we observed several subsets of patients who did not have uniformly favorable outcomes.”

Reference:

Bishop AJ, Landry JP, Roland CL, et al. Certain Risk Factors for Patients With Desmoid Tumors Warrant Reconsideration of Local Therapy Strategies. Cancer. DOI: 10.1002/cncr.32921.