Desmoplastic fibroma is a rare benign bone tumor that typically affects the long bones and jaw bones of young individuals. It is classified as a fibro-osseous lesion due to its nature of involving both fibrous tissue and bone. Although it is non-cancerous, desmoplastic fibroma can be locally aggressive and has the potential to cause significant damage to the affected bone. In this article, we will explore the characteristics, diagnosis, treatment, and outlook for individuals with desmoplastic fibroma in detail.
Desmoplastic fibroma commonly occurs in the bones of the lower extremities, such as the femur and tibia, but it can also involve other bones such as the mandible, maxilla, ribs, and pelvis. The tumor primarily affects children and young adults, with the median age of diagnosis being around 20 years old. It is slightly more common in males than females.
The exact cause of desmoplastic fibroma is still unknown, and it is considered an idiopathic condition, meaning that it arises spontaneously without a known cause. However, there are several theories regarding its origin. Some researchers believe that desmoplastic fibroma may arise from abnormal growth and development of certain cells within the bone, while others suggest that it may result from a genetic predisposition or a disruption in normal bone remodeling processes. Further research is required to understand the exact etiology of this condition.
The clinical presentation of desmoplastic fibroma varies depending on the location and extent of the tumor. In most cases, patients experience pain and swelling around the affected bone. The tumor may cause a noticeable mass or bump, which can lead to cosmetic deformities. If the tumor grows near a joint, it can restrict movement and cause functional impairment. Rarely, desmoplastic fibroma can also lead to pathological fractures, especially in weight-bearing bones.
To diagnose desmoplastic fibroma, a combination of imaging studies and histopathological examination is necessary. X-rays often show a characteristic appearance of an expansile, well-defined osteolytic lesion involving the cortex and medulla of the bone. The tumor frequently exhibits a “soap-bubble” appearance or honeycomb-like pattern on radiographs due to the trabecular bone being replaced fibrous tissue. Magnetic resonance imaging (MRI) provides additional information about the extent of the tumor and its relationship with nearstructures.
However, the definitive diagnosis of desmoplastic fibroma requires a biopsy and histopathological analysis. During a biopsy, a small sample of the tumor is obtained either through a minimally invasive procedure or open surgery. The tissue sample is examined a pathologist who looks for characteristic features such as the presence of spindle-shaped cells within a fibrous stroma and the absence of cellular atypia. Immunohistochemistry may also be performed to confirm the diagnosis and rule out other bone tumors with similar appearances.
Once a diagnosis of desmoplastic fibroma is established, the treatment approach depends on several factors, including the size and location of the tumor, age of the patient, and the presence of symptoms. As the tumor is typically aggressive but non-metastasizing, surgical intervention is the mainstay of treatment. The primary goal of surgery is to achieve complete resection of the tumor while preserving the maximum amount of healthy bone and surrounding structures.
In some cases, when the tumor is smaller and limited to a non-weight-bearing bone or a non-critical area, a conservative approach called curettage may be performed. During curettage, the surgeon removes the tumor scraping it out, followed filling the cavity with a bone graft or bone cement to promote healing and restore bone strength.
For larger tumors or those located in weight-bearing bones, more extensive surgical procedures may be necessary. These procedures may involve the use of bone grafts, metal plates, or screws to reconstruct the bone and restore its strength. In certain situations, limb salvage procedures, such as endoprosthetic replacement or custom-made modular prostheses, may be considered to maintain limb function and minimize disability.
After surgical treatment, regular follow-up with imaging studies is essential to monitor for any signs of local recurrence or complications. Adjuvant therapies such as radiation therapy or chemotherapy are generally not indicated for desmoplastic fibroma unless there is an aggressive or recurrent disease.
The overall prognosis for individuals with desmoplastic fibroma is generally good, given its non-malignant nature. However, the local recurrence rate has been reported to range from 14% to 50%, particularly in cases where complete surgical excision is not achieved or the tumor is located in the spine. Regular follow-up and surveillance are necessary to detect any recurrence early and intervene promptly if required.
Desmoplastic fibroma is a rare benign bone tumor that predominantly affects young individuals. It can be locally aggressive and cause significant damage to the affected bone. Diagnosis is based on imaging studies and histopathological examination, while treatment typically involves surgical resection with the goal of preserving bone integrity and function. Prognosis is generally favorable, but close monitoring is crucial to detect any signs of recurrence.