Multifocal Desmoid-Type Fibromatosis: Case Series and Potential Relationship to Neuronal Spread

Multifocal desmoid-type fibromatosis (DTF) is very rare and usually regional. We report three cases that initially appeared to be multifocal, but subsequent detailed imaging revealed unsuspected tracking along nerves in two cases. This neural spread is reminiscent of neuromuscular choristoma (NMC), a rare developmental lesion in which mature skeletal muscle cells, or rarely smooth muscle cells, infiltrate and enlarge peripheral nerves. NMC is frequently associated with DTF. These two cases suggest that DTF spread along nerves and appeared as distinct multifocal lesions while actually being contiguous. The third case was felt to represent true multifocal tumor development, possibly due to tumor seeding at the time of chest surgery. The relationship of DTF to NMC is discussed.

Introduction and importance: Aggressive fibromatosis or desmoid tumour is a rare soft tissue tumour that develops from supporting tissues and fascia. Although benign, fibromatosis is a tumour that can be locally invasive, and surgical treatment is often difficult. The interest of this observation is to show the particular characteristics of desmoid tumours: the frequency, the major difficulties of excision and the role of adjuvant treatment in the management of these tumours.

Case presentation: The patient was 27 years old male, and had a pathological history of a recurrent desmoid tumour on the dorsal surface of the right foot, which had been present for 10 years, had been operated on 5 times and could not be completely removed. A radiological work-up confirmed the nature of the lesion, necessitating a biopsy, which confirmed the diagnosis of a recurrence of the desmoid tumour on the sole of the foot.

Clinical discussion: Desmoid tumour is a rare tumour with less than 5 cases per million inhabitants, histologically benign and belonging to the deep fibromatosis group. The average age is 30, with a predominance of women. The most common location for desmoid tumours is the abdominal wall, and they are usually single and unilateral. The treatment of desmoid tumours is primarily surgical, but is fraught with technical difficulties due to the absence of any cleavage plane and the particularly tight adhesions to neighbouring structures. Radiotherapy or hormone therapy has been advocated as an adjunct to tumour resection, but its value is debated, and recurrence occurs in 50-80 % of cases.

Conclusion: The desmoid tumour is a very rare tumour, with an infiltrating and aggressive benign character, whose surgical treatment is difficult, and whose evolution is marked by recurrences.

Article in German

A desmoid tumour, also known as aggressive fibrous tumour or desmoid fibromatosis, is a rare, benign tumour originating from connective tissue cells. Desmoid tumours account for approximately 0.03+% of all neoplasms and less than 3+% of all soft tissue tumours. The estimated incidence in the general population is 2 to 4 cases per million people per year [1]. Desmoid tumours are characterised by aggressive growth but typically do not metastasize. They often occur in young adults and preferably affect specific body regions such as the abdomen, shoulder, chest, or extremities. The exact cause of the condition is not fully understood, but genetic changes and hormonal factors may play a role. Symptoms of a desmoid tumour depend on its location and size, with pain, swelling, or restricted movement commonly occurring. A diagnosis is typically made through a tissue sample (biopsy) and imaging techniques such as MRI or CT [2]. To our knowledge, this is the first documented case of recurrence of a desmoid tumour in the scar at the donor site of a latissimus dorsi flap previously used for the reconstruction of desmoid resection in the lower leg.

Introduction and importance: Desmoid tumors (DT), rare benign neoplasms of soft tissues, exhibit local aggressiveness and high recurrence rates. Originating from myofibroblast proliferation, complete surgical intervention is the preferred treatment. Despite their benign nature, these tumors are infrequent, predominantly affecting women between 15 and 60, with a higher incidence in adolescence.

Case presentation: A 44-year-old woman with a DT in the leg mimicking external popliteal sciatic neuropathy. Diagnosis confirmed by biopsy, surgery performed with preservation of the external popliteal nerve, ensuring optimal nerve function. Two-year follow-up with no recurrence, demonstrating the success of the surgical intervention.

Clinical discussion: DTs, although rare, exhibit three distinct genomic mutations, with the 45F genotype associated with the highest risk of recurrence. Generally sporadic, these tumors can be linked to familial adenomatous polyposis (F.A.P.) and influenced by states of hyperestrogenism. DTs typically present as deep-seated masses, with frequent local recurrence despite complete resection.

Conclusion: DTs pose diagnostic and therapeutic challenges, often requiring complete surgical intervention. Management depends on symptomatology, with careful monitoring for small asymptomatic tumors and adjuvant radiotherapy in case of incomplete resection. Despite surgical success, frequent recurrence underscores the need for in-depth research to enhance therapeutic approaches.

Desmoid tumors are soft tissue neoplasms arising from fascial and muscle-aponeurotic structure. These tumors are locally aggressive and have a high recurrence rate, even after complete resection. We present the case of a female with a giant intrathoracic desmoid tumor. She underwent complete surgical resection with no disease recurrence. Desmoid tumors’ natural history is not well defined and is often enigmatic, making these tumors difficult to manage. Currently, for intrathoracic desmoid tumors, medical treatment is the recommended approach, nevertheless, surgery can be considered in selected patients.