Background: Fibromatosis is a rare, noninvasive but aggressive tumor. The tumor displaces tissue by "pushing" the normal structures aside. Optimal treatment should be individualized.
Case: A 35-year-old woman presented with a recurrent fibromatosis, which filled the vagina and extended into the pelvis. The classical surgical removal would have had a high morbidity. Therefore, it was decided, after shared decision-making, to opt for treatment with interferon. The side effects of the therapy were tolerable, and a complete regression of the fibromatosis was achieved. At present, 13 years after the diagnosis and 7 years after discontinuation of the therapy, the patient is well with no signs of disease.
Conclusion: Interferon may be considered as primary treatment for extensive pelvic fibromatosis.