A case of cutaneous malignant fibrous histiocytoma with multiple organ metastases

Abstract

Malignant fibrous histiocytoma is a soft tissue sarcoma that most commonly occurs in the extremities and rarely metastasizes cutaneously. A 79-year-old male patient consulted a dermatologist 11 months after recognizing an intractable ulcer on the right mandible. Punch biopsy revealed eosinophilic tumor cells in the dermal area and proliferation of rich spindle cells. Malignant fibrous histiocytoma or atypical fibroxanthoma was suspected and he was referred to our hospital. Red plaque tumors on the right mandible and right temple were 30 mm and 15 mm in size, respectively. The right mandible lesion was ulcerated. Immunohistochemically, the lesions were positive for CD10, CD74 and alpha-smooth muscle actin. Radiological analysis revealed multiple organ metastases, including bone, liver, lung and skin on the right temple. The patient was diagnosed with malignant fibrous histiocytoma, stage IV and died 8 weeks after the first visit due to respiratory failure. Cutaneous malignant fibrous histiocytoma has a poor prognosis resulting in death.

Cutaneous Metastatic Undifferentiated Pleomorphic Sarcoma from a Mediastinal Sarcoma

“…The local recurrence rate of undifferentiated pleomorphic sarcomas is 19% to 31%, and the metastasis rate is 31% to 35% after tumor resection with a clear resection margin5. Despite the high distant metastasis rate, cutaneous metastasis is very rare 6.…”

“…Despite the high distant metastasis rate, cutaneous metastasis is very rare 6. The most common sites of metastasis are the lungs (90%), bone (8%), and liver (1%)5,6. Meanwhile, the cutaneous metastasis rate is 0.6% to 1.5%7,8.…”

“…Meanwhile, the cutaneous metastasis rate is 0.6% to 1.5%7,8. To our knowledge, only 10 cases of cutaneous metastasis have been reported (Table 1)5,6,7,8,9,10,11,12. Clinically, patients complain of a mass appearing rapidly, ranging from weeks to months13.…”

“…In the present case, the patient did not complain of pain. Histologically, undifferentiated pleomorphic sarcoma is characterized by the presence of spokes of a wheel-like structure, showing spindle-shaped cells such as fibrocytes and histiocytes arranged in a storiform pattern3,5,14. Numerous giant cells show eosinophilic cytoplasm on staining; single or multiple irregular nuclei are observed, with inflammatory cells often mixing with the tumor cells13.…”

“…The differential diagnosis includes metaplastic (sarcomatoid) carcinoma, fibrosarcoma and other tumors such as malignant phyllodes tumor, inflammatory myofibroblastic tumor, and dermatofibrosarcoma1,5. Metaplastic (i.e., sarcomatoid) carcinoma, also called spindle cell carcinoma, is confirmed by CK positivity1.…”