Spontaneous Remission of Solitary-Type Infantile Myofibromatosis

Infantile myofibromatosis is a rare fibrous tumor of infancy. The cutaneous solitary type has typically an excellent prognosis. However, histologically, it is important to rule out leiomyosarcoma, which has a poor prognosis. The low frequency of mitosis was definitive for a diagnosis of infantile myofibromatosis. We present a cutaneous solitary-type case of infantile myofibromatosis. Following incisional biopsy, the tumor remitted spontaneously

Metastatic Patterns of Myxoid/Round Cell Liposarcoma: A Review of a 25-Year Experience

Myxoid/round cell liposarcoma (MRCL), unlike other soft tissue sarcomas, has been associated with unusual pattern of metastasis to extrapulmonary sites. In an attempt to elucidate the clinical features of MRCL with metastatic lesions, 58 cases, from the medical database of Keio University Hospital were used for the evaluation. 47 patients (81%) had no metastases, whereas 11 patients (11%) had metastases during their clinical course. Among the 11 patients with metastatic lesions, 8 patients (73%) had extrapulmonary metastases and 3 patients (27%) had pulmonary metastases. Patients were further divided into three groups; without metastasis, with extrapulmonary metastasis, and with pulmonary metastasis. When the metastatic patterns were stratified according to tumor size, there was statistical significance between the three groups (P = 0.028). The 8 cases with extrapulmonary metastases were all larger than 10 cm. Similarly, histological grading had a significant impact on metastatic patterns (P = 0.027). 3 cases with pulmonary metastatic lesions were all diagnosed as high grade. In conclusion, large size and low histological grade were significantly associated with extrapulmonary metastasis

Natural evolution of desmoplastic fibroblastoma on magnetic resonance imaging: a case report

<p>Abstract</p> <p>Introduction</p> <p>Desmoplastic fibroblastoma (collagenous fibroma) is a recently described tumor thought to arise predominantly from subcutaneous tissue or skeletal muscle. The natural evolution of this tumor on magnetic resonance imaging has never been described, to the best of our knowledge. We herein report a case of desmoplastic fibroblastoma arising in the thigh and show the longitudinal magnetic resonance imaging findings.</p> <p>Case presentation</p> <p>A 60-year-old Japanese man presented with swelling of the medial side of his right thigh, and he complained of nighttime pain and slight tenderness. Magnetic resonance imaging demonstrated a 4 × 4 cm mass in the right thigh. Open biopsy was performed. The mass was diagnosed histologically as a benign fibrous tumor, and we maintained follow-up without surgical therapy. After one year, magnetic resonance imaging showed an increase in tumor size to 4 × 5 cm, but the histologic findings were the same as those obtained one year earlier. Resection was performed with narrow surgical margins. Pathologic diagnosis was desmoplastic fibroblastoma. Two years after surgery, the patient is free from pain and shows no signs or symptoms of recurrence.</p> <p>Conclusion</p> <p>The natural evolution of desmoplastic fibroblastoma is characterized by no changes in patterns on magnetic resonance imaging despite increasing size. This finding is clinically helpful for distinguishing desmoplastic fibroblastoma with increasing pain from the desmoid tumor.</p