| disease | Fibrous Fibroma |
| alias | Desmoplastic Fibroma |
Fibrous fibroma is a mature fibroma, similar to the desmoid tumor of soft tissue, and like them, it is prone to recurrence.
bubble_chart Pathological Changes
1. Gross appearance: The typical desmoplastic fibroma presents as a dense, bright tendon-like white tissue, arranged in bundles or whorls, with a well-defined boundary.
2. Microscopic appearance: It consists of dense and variably mature fibrous tissue, with varying proportions of fibroblasts and collagen fibers throughout. Fibroblasts are not abundant, appearing small and of varying maturity, with nuclei that are not plump and lightly stained. Mitotic figures are rare or absent. Collagen fibers are abundant, often forming wavy bands or even hyalinized dense areas. The tumor's boundary is less distinct than in gross pathology, tending to blend into the surrounding tissue.
bubble_chart Clinical Manifestations
This disease is rare. There is no significant gender difference. It can occur in all age groups, but at the time of diagnosis, 90% of patients are under 30 years old. There is no clear predilection for specific sites, and it can occur in any bone of the entire skeletal system. In long bones (especially the femur, humerus, and tibia), it is more common in the metaphysis, but can also be seen in the diaphysis, and often extends to the epiphysis in adulthood.
Symptoms are mild and appear late, including moderate pain, pathological fractures, and occasionally significant bone expansion.
bubble_chart Auxiliary Examination
X-ray findings Due to the lack of symptoms, when X-rays are taken during the initial diagnosis, desmoplastic fibroma often already reaches a considerable size. The imaging shows osteolytic lesions, sometimes regular, and sometimes presenting a foamy appearance due to the presence of parietal bone ridges. The bone cortex may be eccentrically thinned, or the entire cortical bone may be thinned.
Desmoplastic fibroma exhibits only moderate, diffuse enhancement staining in stirred pulse contrast imaging. On bone scans, it appears as a relatively "cold area."bubble_chart Treatment Measures
Approximately half of the cases may recur after curettage, so the preferred treatment for desmoplastic fibroma is marginal or wide en bloc resection. With this method, even severely expanded cases can be cured.
Fibrous fibromas grow slowly or very slowly and can exist for years before causing noticeable symptoms, with no distant metastasis ever occurring.
For a long-standing, large, bubbly, osteolytic lesion with no malignant features, the diagnosis of desmoplastic fibroma should be considered. Histologically, desmoplastic fibroma must be distinguished from grade I fibrosarcoma, which has more cells and more plump, pleomorphic nuclei, often with mitotic figures. In fact, there is no clear distinction between desmoplastic fibroma and low-grade fibrosarcoma, making differentiation difficult in some cases.
