Initial Active Surveillance Strategy for Patients with Peripheral Sporadic Primary Desmoid-Type Fibromatosis: A Multicentric Phase II Observational Trial

Active surveillance and emerging medical treatment options for desmoid: when and for whom?

PURPOSE OF REVIEW

This article discusses the evolving approaches to desmoid tumors management, shedding light on recent developments.

RECENT FINDINGS

Active surveillance has become the primary approach for managing primary peripheral desmoid tumors. This strategy was initially based on evidence from retrospective studies. Roughly 50% of cases managed with active surveillance show spontaneous stabilization or regression. Recent prospective trials conducted in Italy, The Netherlands, and France (2022-2023) confirm the efficacy of active surveillance, revealing 3-year progression-free survival rates ranging from 53.4 to 58%. For the patients under active surveillance, decisions regarding treatment are based on significant tumor growth or progressive symptoms. Moreover, three contemporary randomized trials investigated medical treatments for progressive or recurrent desmoid tumors. Sorafenib, pazopanib, and nirogacestat demonstrated clinical activity, as evidenced by favorable progression-free survival and objective response rates.

SUMMARY

Active surveillance has solidified its position as the primary management approach for desmoid tumors, validated by three robust prospective studies. Three recent randomized trials explored medical treatment for progressive or recurrent desmoid tumors, revealing promising clinical activities.

Real-word experience of pazopanib and sorafenib in patients with desmoid tumors: A CanSaRCC multi-center study

BACKGROUND

Sorafenib and pazopanib, two tyrosine kinase inhibitors (TKI), are widely used in patients with progressive symptomatic desmoid tumors (DT). Limited real-word data is available on long-term outcomes of patients who progressed on, stopped, or continued TKIs.

METHODS

Patients diagnosed with DTs and treated with sorafenib or pazopanib between 2011 and 2022 at 11 institutions were reviewed. Patient history, response to therapy and toxicity were recorded. Statistical analyses utilized Kaplan-Meier and log-rank tests.

RESULTS

142 patients with DT treated with sorafenib (n = 126, 88.7 %) or pazopanib (n = 16, 11.3 %) were analyzed. The median treatment duration was 10.8 months (range: 0.07- 73.9). The overall response rate and the disease control rate were 26.0 % and 95.1 %, respectively. The median tumor shrinkage was - 8.5 % (range -100.0 %- +72.5 %). Among responders, the median time to an objective response was 15.2 months (range: 1.1 to 33.1). The 1-year and 2-year progression-free survival rates were 82 % and 80 %. Dose reductions were necessary in 34 (23.9 %) patients. Grade 3 or higher adverse events were reported in 36 (25.4 %) patients. On the last follow-up, 55 (38.7 %) patients continued treatment. Treatment discontinuation (n = 85, 59.9 %) was mainly for toxicity (n = 35, 45.9 %) or radiological or clinical progression (n = 30, 35.3 %). For the entire cohort, 36 (25.4 %) patients required subsequent treatment. In the 32 responders, only 1 (3.1 %) patient required a subsequent treatment. In patients who discontinued TKI, 25 (44.6 %) with stable disease received subsequent treatment compared to 0 (0.0 %) of responders.

CONCLUSION

This retrospective study represents the largest cohort of DT patients treated with sorafenib or pazopanib to date. Discontinuation of treatment in responders is safe. The optimal treatment duration in patients with stable disease remains to be defined.

Current Management of Desmoid Tumors: A Review

Importance

Desmoid tumor (DT) is a rare and locally aggressive monoclonal, fibroblastic proliferation characterized by a variable and often unpredictable clinical course. Previously, surgery was the standard primary treatment modality; however, within the past decade, a paradigm shift toward less-invasive management has been introduced and an effort to harmonize the strategy among clinicians has been made. To update the 2020 global evidence-based consensus guideline on the management of patients with DT, the Desmoid Tumor Working Group convened a 1-day consensus meeting in Milan, Italy, on June 30, 2023, under the auspices of the European Reference Network on Rare Adult Solid Cancers and Sarcoma Patient Advocacy Global Network, the Desmoid Foundation Italy, and the Desmoid Tumor Research Foundation. The meeting brought together over 90 adult and pediatric sarcoma experts from different disciplines as well as patients and patient advocates from around the world.

Observations

The 2023 update of the global evidence-based consensus guideline focused on the positioning of local therapies alongside surgery and radiotherapy in the treatment algorithm as well as the positioning of the newest class of medical agents, such as γ-secretase inhibitors. Literature searches of MEDLINE and Embase databases were performed for English-language randomized clinical trials (RCTs) of systemic therapies to obtain data to support the consensus recommendations. Of the 18 full-text articles retrieved, only 4 articles met the inclusion criteria. The 2023 consensus guideline is informed by a number of new aspects, including data for local ablative therapies such as cryotherapy; other indications for surgery; and the γ-secretase inhibitor nirogacestat, the first representative of the newest class of medical agents and first approved drug for DT. Management of DT is complex and should be carried out exclusively in designated DT referral centers equipped with a multidisciplinary tumor board. Selection of the appropriate strategy should consider DT-related symptoms, associated risks, tumor location, disease morbidities, available treatment options, and preferences of individual patients.

Conclusions and Relevance

The therapeutic armamentarium of DT therapy is continually expanding. It is imperative to carefully select the management strategy for each patient with DT to optimize tumor control and enhance quality of life.

Desmoid-type fibromatosis: Current therapeutic strategies and future perspectives

Desmoid tumors (DT) are rare, slow-growing, locally invasive soft tissue tumors that often pose significant therapeutic challenges. Traditional management strategies including active surveillance, surgery, radiotherapy, and systemic therapy which are associated with varying recurrence rates and high morbidity. Given the challenging nature of DT and the modest outcomes associated with current treatment strategies, there has been a growing interest in the field of γ-secretase inhibitors as a result of its action on the Wnt/β-catenin signaling pathway. In this review article, we will shed the light on the pathogenesis and molecular biology of DT, discuss its symptoms and diagnosis, and provide a comprehensive review of the traditional therapeutic approaches. We will also delve into the mechanisms of action of γ-secretase inhibitors, its efficacy, and the existing preclinical and clinical data available to date on the use of these agents, as well as the potential challenges and future prospects in the treatment landscape of these tumors.