Desmoplastic fibroblastoma (collagenous fibroma) on the mandibular ridge: case report and review of immunohistochemical markers

The desmoplastic fibroblastoma (DF) is a rare benign soft-tissue tumor of fibroblastic and myofibroblastic origin, and its occurrence in the oral cavity is rare. This study details a new case of an elevated lesion in the alveolar ridge of a 59-year-old woman, painful during mastication. The histopathological exam showed non-encapsulated stellate-to-spindle cells proliferation in a hypocellular collagen-rich stroma. Tumor cells were strongly and diffusely positive for vimentin, and some cells were focally positive for α-smooth muscle actin, CD99, and β-catenin. The exams were conclusive for DF diagnosis. The patient is in the follow-up period, and no recurrent lesions were detected within one year. Despite having similar clinical, pathological, and immunohistochemical features to the cases previously described, the DF in this report is at an unusual oral site and associated with painful symptomatology. Immunohistochemistry is an important tool in DF cases where the histopathological examination is not conclusive.

A desmoplastic fibroblastoma that developed in the anterior mediastinum: a case report

Background Desmoplastic fibroblastoma (also known as collagenous fibroma) is a benign, slowly growing soft-tissue tumor. Most desmoplastic fibroblastomas develop in the limbs, neck, or trunk. A mediastinal origin is quite rare. Case presentation A 32-year-old Asian female was referred to us for the diagnosis and treatment of an anterior mediastinal tumor. The tumor was 80 mm in the largest diameter and was located on the pericardium. No invasion was evident. She underwent resection of the tumor via video-assisted thoracoscopic resection. The tumor was totally encapsulated, and its pedicle was on the pericardium. The resected specimen was very rigid, making it difficult to remove from the intercostal space. Histologically, the tumor was composed of a paucicellular dense collagenous tissue. Mitosis was rarely observed, and cellular atypia was not evident, suggesting that the tumor was benign. We diagnosed the tumor as a desmoplastic fibroblastoma by morphology and immunohistochemistry. Conclusions Desmoplastic fibroblastoma of the mediastinum is an extremely rare disease. Preoperative diagnosis is difficult. Early surgical resection is suitable for diagnosis and treatment planning.

A Desmoplastic Fibroblastoma that Developed in the Anterior Mediastinum

Background:Desmoplastic fibroblastoma (also known as collagenous fibroma) is a benign, slowly growing soft tissue tumor. Most desmoplastic fibroblastomas develop in the limbs, neck, or trunk. A mediastinal origin is quite rare.Case presentation:A 32-year-old female was referred to us for the diagnosis and treatment of an anterior mediastinal tumor. The tumor was 80 mm in the largest diameter and was located on the pericardium. No invasion was evident. She underwent resection of the tumor via video-assisted thoracoscopic resection. The tumor was totally encapsulated, and its pedicle was on the pericardium. The resected specimen was very rigid, making it difficult to remove from the intercostal space. Histologically, the tumor was composed of a paucicellular dense collagenous tissue. Mitosis was rarely observed, and cellular atypia was not evident, suggesting that the tumor was benign. We diagnosed the tumor as a desmoplastic fibroblastoma by morphology and immunohistochemistry.Conclusions:Desmoplastic fibroblastoma of the mediastinum is a rare disease. Preoperative diagnosis is difficult. Early surgical resection is suitable for diagnosis and treatment planning.

Desmoplastic Fibroblastoma (Collagenous Fibroma): A Case Report

Desmoplastic Fibroblastoma(DF) is a rare fibrotic tumor that has a wide anatomic distribution and it can appearin deep sections of the subcutis, in fascia, in aponeurosis or in skeletal muscles that rarely involving bone.