The Desmoid Tumor Research Foundation

April 2025

Impact and safety of pregnancy on desmoid fibromatosis management in the era of active surveillance. An international multicenter retrospective observational study

Author Information

Marco Fiore 1, Silva Ljevar 2, Chandraijt Premanand Raut 3, Giulia Personeni 4, Mikhael Rabih 5, Rebecca Gladdy 6, Kelly Mercier 7, Megan Sulciner 3, Enrica Rossi 4, Dimitri Tzanis 5, Harini Suraweera 6, Chiara Colombo 8, Marianna Coppola 4, Sylvie Bonvalot 5, Sara Iadecola 2, Catherine Sarre-Lazcano 4, Costanza Figura 8, Daniela Salvatore 8, Rosalba Miceli 2, Alessandro Gronchi 8

1Sarcoma Service, Department of Surgery, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. Electronic address: https://twitter.com/@FioreDoc. 2Unit of Biostatistics for Clinical Research, Department Epidemiology and Data Science, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. 3Brigham and Women's Hospital, Boston, MA, USA; Dana-Farber Cancer Institute, Boston, MA, USA; Harvard Medical School, Boston, MA, USA. 4Desmoid Foundation Italy, Milan, Italy. 5Institut Curie, Paris, France. 6Division of Surgical Oncology, Mount Sinai and Princess Margaret Cancer Center, University of Toronto, Canada. 7Desmoid Tumor Research Foundation, Woodcliff Lake, NJ, USA; Duke University, Durham, NC, USA. 8Sarcoma Service, Department of Surgery, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.

Publication

Eur J Cancer

Summary

Aim: To evaluate desmoid fibromatosis (DF) progression and obstetric outcomes during and after pregnancy, providing evidence to inform clinical decision-making and counseling. Methods: This international, multicenter, retrospective observational study included data from 157 women with DF, contributing 177 pregnancies. Women were classified into three groups: DF diagnosed during pregnancy (Group A), pregnancy occurring after the diagnosis of DF (Group B: DF in situ during pregnancy), or pregnancy in previously resected DF (Group C). Logistic regression and tumor size trend analyses were conducted. Results: Among 177 pregnancies, Group A exhibited the highest rates of DF progression (68.7 % during pregnancy, 40.6 % postpartum), while Groups B and C had lower progression rates (9.5 % during pregnancy, 8.3 % postpartum). Active treatment was required in 5.6 % of cases. Spontaneous regression occurred in 23.7 % of pregnancies, particularly following progression. Obstetric complications were comparable to those in the general population. Conclusion: Pregnancy is generally safe for women with DF, particularly after prolonged disease stability. Individualized counseling is essential for managing risks of progression and recurrence, supporting informed fertility decisions. Referral to specialized centers is recommended to optimize DF management during family planning and pregnancy.

View Abstract