Targeted therapy in advanced desmoid tumors: Current perspectives

Background

Desmoid tumors/aggressive fibromatosis (DTs/AF) are cytological bland fibrous neoplasms originating from the musculoaponeurotic structures throughout the body. The exact cause still remains unknown, however, they may present sporadically or as a manifestation of a hereditary syndrome called familial adenomatous polyposis (FAP). Although they lack the capacity to establish metastases, DTs/AF may be devastated and occasionally fatal. As a result of the heterogeneity of DTs/AF, treatment needs to be individualized to improve local tumor control and maintain patients’ quality of life. Therefore, after a multidisciplinary approach, all treatment options should be discussed with patients. Where systemic chemotherapy has been shown to be unsuccessful with marked side effects in case of advanced DTs/AF, new therapeutic options are needed.

Methods

A Medline search was conducted and published articles in different studies from 2000 to the present were reviewed.

Conclusion

More research is needed to illustrate both the prognostic and predictive factors of the targeted therapy and the value of their combinations with or without other treatment modalities to get the best result for the treatment of advanced DTs/AF.

[Systemic therapy of sarcomas : New biomarkers and therapeutic strategies]

Diagnostics and treatment of mesenchymal tumors (i.e. soft tissue sarcomas, gastrointestinal stromal tumors, and bone sarcomas) have changed dramatically in the past few years. Molecular and immunohistochemical biomarkers contribute significantly to improved diagnostics. They also play an increasing role in terms of clinical treatment decisions.Grading and tumor type-specific outcome data provide the basis for adjuvant chemotherapy of localized sarcomas. Recurrent gene fusions become more important as predictive biomarkers for targeted therapies in the context of systemic treatments. Immuno-oncology-based approaches are currently being studied in clinical trials, and the first responses of selected patients have been demonstrated. However, the role of predictive biomarkers in this field, such as PD-L1, still needs to be elucidated. Comprehensive genetic analyses of metastatic sarcomas will continue to identify additional therapeutic targets and the corresponding biomarkers.

Evidence of hydroxyurea activity in children with pretreated desmoid-type fibromatosis: A new option in the armamentarium of systemic therapies

INTRODUCTION

The treatment paradigm in desmoid-type fibromatosis (DF) has changed in recent years from a surgery-based strategy to a multidisciplinary approach that includes systemic therapies. Among various medical therapies, hydroxyurea has been considered of potential interest. This case series summarizes the experience gained at four centers using hydroxyurea in relapsing DF.

METHODS

Eligibility requirements were age < 21 years, histologically confirmed DF, and progressive or recurrent disease after at least one line of systemic therapy. Hydroxyurea was given orally at an initial dose of 20 mg/kg/day (escalated up to 30 mg/kg/day as necessary, if well tolerated).

RESULTS

The series included 16 patients treated between 2008 and 2016. Hydroxyurea was the second systemic therapy in nine cases, and the third (at least) in seven. There was no reported G3-G4 hematological toxicity, and one case of G3 diarrhea. Dose reductions were reported in three cases (due to G2 neutropenia). The response rate was 18.7% major partial remissions, 37.5% considering any amount of shrinkage, 68.7% considering symptom response or signs of tissue response as well. In patients with no progression, the treatment was continued for 9-24 months.

CONCLUSION

This is the first published series on the efficacy of hydroxyurea in pediatric DF. The response rate was moderate, but similar to that reported for other medical therapies currently considered as treatment options in this disease. Though further, larger series are needed to confirm as much, hydroxyurea has potential as an effective alternative therapy for DF.