Dermatofibroma (DF) is a common, benign fibrohistiocytic tumor with unknown pathogenesis. There are multiple uncommon histologic variants of DF reported in literature, one of which is hemosiderotic DF. It can variably present as a pigmented papule or nodule commonly located on the lower extremities. Hemosiderotic DF remains to be underreported in the Philippines despite the widely available dermatopathology services in the country.
Human ; dermatofibroma ; histiocytoma, benign fibrous

Pseudomyogenic hemangioendothelioma (PHE) is a rare angiogenic tumor. Histologically, the morphological characteristics of neoplastic vessels and endothelial differentiation are not obvious, and it is easy to be confused with epithelioid sarcoma, epithelioid hemangioendothelioma and myogenic tumor. PHE usually occurs in arms and legs in young people and has a significant male predominance. The tumor has a predilection for the distal extremities and its typical manifestation is multiple center invasion of a single limb, which can involve all layers of skin and subcutaneous tissues,and is often accompanied by abvious pain. Histologically, PHE is characterized by infiltrative growth of tumor. Most tumor lesions are composed of sheets and loose fascicles of plump spindle or epithelioid cells within a background of variably prominent inflammatory infiltration, which was commonly composed of neutrophils. Some cells may resemble rhabdomyoblasts, and nuclear atypia and mitosis were rare. The tumor cells generally expressed positive cytokeratin (CK), ETS-related gene (ERG), Friend leukemia virus integration 1 (FLI1) and integrase interactor 1(INI1). In some cases, the tumor cells expressed CD31. A case of a young woman was reported in this paper, who presented with a subcutaneous mass with severe pain and was chronologically misdiagnosed with herpes zoster, low-grade malignant fibrous histiocytoma and epithelioid hemangioendothelioma. In this study, the clinical and pathological features, differential diagnosis and the latest progress in therapy of PHE were analyzed based on relevant literature.
Adolescent ; Adult ; Biomarkers, Tumor ; Child ; Diagnosis, Differential ; Diagnostic Errors ; Female ; Hemangioendothelioma, Epithelioid/pathology* ; Hemangioma ; Histiocytoma, Malignant Fibrous/diagnosis* ; Humans ; Male ; Pain ; Precancerous Conditions/diagnosis*

Histiocytoma, Benign Fibrous/surgery* ; Humans ; Splenectomy ; Splenic Diseases/pathology* ; Splenic Neoplasms/surgery*

Humans ; RNA-Binding Protein EWS/genetics* ; Histiocytoma, Malignant Fibrous/pathology* ; Oncogene Proteins, Fusion/genetics* ; Biomarkers, Tumor ; Cyclic AMP Response Element-Binding Protein/genetics*

Dermatofibroma is a fibrohistiocytic tumor of the skin that commonly occurs as a solitary lesion on the lower extremities of young women. Multiple eruptive dermatofibromas (MEDFs), defined as the presence of 5 to 8 dermatofibromas appearing within a period of 4 months, are rare, and the etiology of MEDFs remains unknown. However, MEDFs are frequently thought to be associated with altered immunity, such as autoimmune diseases and immunosuppression. It is unclear why MEDFs occur in association with these conditions, but this relationship may suggest that MEDFs are the result of an abortive immunoreactive process. We herein describe a middle-aged woman who developed multiple dermatofibroma. She had myasthenia gravis for 8 years, and developed MEDFs after undergoing oral corticosteroid treatment (245 mg/week) for 3 months. Therefore, our case suggests that the use of immunosuppressants is a more dominant factor for the development of MEDFs than underlying autoimmune diseases.
Autoimmune Diseases ; Female ; Histiocytoma, Benign Fibrous ; Humans ; Immunosuppression ; Immunosuppressive Agents ; Lower Extremity ; Myasthenia Gravis ; Skin

BACKGROUND: The occurrence of cutaneous malignant tumors has been increasing worldwide due to changes in various environmental factors. OBJECTIVE: Our study aimed to analyze the overall tendency of clinical characteristics in single-center patients with cutaneous malignant tumors according to sex, age, duration, size, anatomic site, treatment, and concomitant diseases. METHODS: We retrospectively reviewed the medical records and clinical photographs of 319 patients diagnosed with cutaneous malignant tumors (basal cell carcinoma, squamous cell carcinoma, melanoma, lymphoma, Paget's disease, metastatic skin cancer, mycosis fungoides, angiosarcoma, dermatofibrosarcoma protuberans, Kaposi sarcoma, malignant fibrous histiocytoma, Merkel cell carcinoma) and 109 patients diagnosed with premalignant tumors (Bowen's disease) between January 2007 and January 2017. RESULTS: The average annual incidence of malignant cutaneous tumors was 2.4%. In total, 158 males (36.9%) and 270 females (63.1%) were included with a mean age of onset of 66 years. Among the malignant tumors, basal cell carcinoma (30.8%) was the most common, while the incidences of squamous cell carcinoma (18.9%), melanoma (6.3%), and lymphoma (4.4%) were also high. The predominantly involved anatomic sites were the face (67.3%), trunk (11.5%), and legs (10.9%). Most cases involved solitarily existing tumors (77.3%), and pruritus (21.7%) was the most common accompanying symptom. Among the 69.6% of patients who received treatment for their tumors, the most common method was surgical removal. No significant increase in concomitant diseases or environmental factors was detected. CONCLUSION: Our study is meaningful as an overall and recent review of various types of cutaneous malignancies that provides preliminary data for further large-scale nationwide studies.
Age of Onset ; Carcinoma, Basal Cell ; Carcinoma, Squamous Cell ; Chungcheongnam-do ; Dermatofibrosarcoma ; Female ; Hemangiosarcoma ; Histiocytoma, Malignant Fibrous ; Humans ; Incidence ; Leg ; Lymphoma ; Male ; Medical Records ; Melanoma ; Methods ; Mycosis Fungoides ; Pruritus ; Retrospective Studies ; Sarcoma, Kaposi ; Skin Neoplasms ; Statistics as Topic

Primary malignant fibrous histiocytoma (MFH) of the chest wall is extremely rare and is characterized by aggressive features, including a high incidence of local recurrence and distant metastasis. Surgical resection of the chest wall is the primary modality of management. However, surgical treatment is not generally recommended in patients with evidence of distant metastasis. Here, we present a case of chest wall MFH along with a schwannoma mimicking distant metastasis in the right upper arm. The patient was treated by radical en bloc resection and survived for more than 9 years without recurrence.
Arm ; Histiocytoma, Malignant Fibrous ; Humans ; Incidence ; Neoplasm Metastasis ; Neurilemmoma ; Positron-Emission Tomography ; Recurrence ; Thoracic Wall ; Thorax

OBJECTIVE: To investigate ultrasound and MRI features of malignant fibrous histiocytoma (MFH) of soft tissue. METHODS: Ultrasound, MRI images and pathological data of 12 patients with malignant fibrous histiocytoma in soft tissue confirmed by operation and pathology were analyzed from January 2012 to August 2018, inlcuding 7 males and 5 females, aged from 36 to 69 years old with an average age of 53 years old; the courses of disease ranged from 4 to 49 months with an average of 28 months. Clinical manifestations were soft tissue masses and pain in the affected limbs. Ultrasound, MRI and contrast-enhanced examination were performed before operation. The lesions, morphology, echo/signal characteristics, color flow signals and enhancement features were observed and compared with pathology. RESULTS: In 12 patients with MFH, 9 patients were primary lesions and 3 patients were recurrent lesions after operation. There were 7 cases of bilateral thighs, 2 cases of calves, 1 case of upper arm, 1 case of buttocks and 1 case of posterior peritoneum. The size ranged from 5.1 to 17.1 cm with an average of 8.7 cm. Ultrasound feature showed lobulated or agglomerate, and focused on low echo; 5 cases had capsule and with clear border; 7 cases were unclear boundary with surrounding tissues; and 6 cases with irregular echo-free. The blood flow signals were around the CDFI, and the internal blood flow signals were different. MRI feature showed lobulated, agglomerate or irregular shape, T1WI showed slightly lower signal or equal signal, T2WI showed high signal and DWI signal increased. Six patients manifested mixed signal inside, 7 patients manifested low signal separation inside, 5 patients with false envelope, and 9 patients manifested infiltration and growth with peripheral edema. T1WI showed uneven strengthening after enhancement. Immunohistochemical expression of Vim, CD68 were positive. CONCLUSIONS The age, location and imaging features of soft tissue MFH are characteristic. The diagnosis of MFH should be considered when irregular mass occurred in soft tissues of limbs at middle-aged and old people. Echo and signal are homogeneous or mixed. Separation, necrosis and cystic degeneration could be seen in the mass. When the blood flow signals are abundant and solid components are obviously enhanced, the diagnosis of MFH should be considered.
Adult ; Aged ; Edema ; Extremities ; Female ; Histiocytoma, Malignant Fibrous ; diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Ultrasonography

Arm ; Fibroma ; Histiocytoma, Malignant Fibrous ; Humans ; Soft Tissue Neoplasms

No abstract available.
Diagnosis, Differential ; Histiocytoma, Benign Fibrous ; Xanthogranuloma, Juvenile