A present a clinical case of a rare variant of dermatofibroma (aneurysmatic type), is presented in a 72-year-old female patient, the lesion was located in the right arm’s flexural fold, resulting from mesenchymal proliferation associated with blood vessels and tissular hemorrhage, with its own well defined histological characteristics. The objectives are to describe the rarity of the lesion and its histopathologic importance, when compared to other benign and malignant tumors in the differential diagnosis, in addition to the terminology currently used.

Keywords: BENIGN FIBROUS HISTIOCYTOMA, MALIGNANT FIBROUS HISTIOCYTOMA, HEMOSIDERIN

Introduction: Primary cutaneous sarcomas are rare mesenchymal cancers with histopathological heterogeneity. Angiosarcomas are an uncommon cutaneous malignant sarcoma sub-type that effect mainly elderly male patients.Their location is primarily cephalic, and they present as multifocal lesions which lead to local edema, bleeding and ulceration. Aggressiveness, fast growth and undefined surgical margins explain the high rates of recurrence.We describe a case of primary angiosarcoma of the scalp in an elderly female patient, who was being treated with a multidrug therapy for lepromatous leprosy.The combination of angiosarcoma and leprosy is uncommon, and the absence of similar reports in the literature motivated the description of this case.

Keywords: SKIN NEOPLASMS, SARCOMA, LEPROSY, LEPROMATOUS

Dermatofibrosarcoma protuberans is a spindle cell neoplasm of intermediate malignancy, nonetheless it presents a high risk of local recurrence. It mainly affects the trunk and limbs, and is rare on the face. The treatment of the tumor can be carried out using conventional surgery with wide surgical margins or Mohs micrographic surgery. Radiation and chemotherapy can be indicated in selected cases. The present article reports the case of a 39-year-old male patient with a 0.7cm yellowish papule on the forehead, whose biopsy and immunohistochemistry confirmed the tumor's diagnosis. The lesion was treated through Mohs micrographic surgery with good aesthetic results.

Keywords: DERMATOFIBROSARCOMA; SARCOMA; MOHS SURGERY

The solitary dermatofibroma or benign superficial fibrous histiocytoma is a common tumor that arises in the lower limbs of young women. Multiple eruptive dermatofibromas constitute a rare presentation of dermatofibromas (0.3%), often associated with underlying diseases. They are defined by the presence of 15 or more lesions or the appearance of five to eight tumors within less than four months. On PubMed/MEDLINE, to date, there are about 40 published cases of multiple eruptive dermatofibromas related to systemic diseases such as systemic lupus erythematosus, Sjögren's syndrome, hepatitis C, AIDS and the use of imunossupressants. The authors report a case where the emergence of multiple eruptive dermatofibromas preceded the onset of systemic lupus erythematosus by 20 years.

Keywords: HISTIOCYTOMA, BENIGN FIBROUS; LUPUS ERYTHEMATOSUS, SYSTEMIC; IMMUNOSUPPRESSIVE AGENTS.

Kaposi's sarcoma is a rare multicentric neoplasm originating from endothelial cells, with cutaneous and extracutaneous manifestation. The present paper describes a case of an uncommon clinic variant of a Kaposi’s sarcoma in a 32 year-old male patient bearer of acquired immunodeficiency syndrome (AIDS), with regression after undergoing combined treatment with antiretroviral therapy and radiotherapy.

Keywords: sarcoma, kaposi; herpesvirus 8, human; acquired immunodeficiency syndrome; keloid

Angiosarcoma is a rare and aggressive vascular neoplasia that can occur anywhere in the skin integument, especially in the face and scalp. It has a branched character, and can clinically arise as a macula, papule, plaque or nodule of erythematous hue, with imprecise limits and expansive growth, and diagnosis based on the clinical-pathological correlation. In the present study, the authors report the case of a patient with exuberant cutaneous angiosarcoma on the face, where surgical resection was performed as the first therapeutic option.

Keywords: Dermatology; Hemangiosarcoma; Sarcoma; Vascular neoplasms

INTRODUCTION: Dermatofibrosarcoma protuberans (DFSP) is a local aggressive sarcoma that presents 60% of recurrences. Rarely it presents lung metastasis too.
METHODS: 41 years old man presented a soft tumor in his right hallux for two years. Histopathology has shown spindle-shaped cells arranged in a storiform manner, and immunohistochemistry was CD34 positive.
DISCUSSION: The literature describes some clinical types of DFSP. The most common are: confluent nodules forming a plaque, sometimes similar to keloids, tumoral lesions, and atrophic plaques.
CONCLUSION: DFSP cases simulating a subcutaneous cyst have been described in the literature; nevertheless, it is an unusual presentation of this tumor.

Keywords: Dermatofibrosarcoma; Sarcoma; Surgical Procedures, Minor

Dermatofibrosarcoma protuberans is a locally aggressive sarcoma of intermediate malignancy that predominates in the range of young adults to middle age. Congenital or childhood lesions are rare but have been reported. It can be misdiagnosed and incompletely excised in the early stages, which increases the risk of recurrence. The present article reports the case of a 24-year-old male patient presenting a hyperchromic macula in the abdominal region from birth that evolved into a tumor after several surgical approaches. Biopsy and immunohistochemistry confirmed the diagnosis of dermatofibrosarcoma protuberans, and the lesion was excised with a 3 cm margin.

Keywords: Dermatofibrosarcoma; Neoplasms, Fibrous Tissue; Sarcoma

Undifferentiated sarcomas are neoplasms of soft tissues derived from the mesoderm. We report a case of undifferentiated pleomorphic sarcoma, its dermoscopy, staging, and therapeutic approach.

Keywords: Dermoscopy; Sarcoma; Soft Tissue Neoplasms

Aneurysmal dermatofibroma (DF) is a rare benign tumor originating in the dermis, considered a variant of dermatofibroma. It is more prevalent in women over 30 years of age, in the lower limbs. Its etiology is unknown and histopathological examination confirms the diagnosis. This study reports two cases of aneurysmal DF in young patients, both men, presenting similar lesions: single hyperchromic nodule, with approximately 1.5 cm and progressive growth. This report aims to demonstrate an uncommon variant of dermatofibroma and to highlight the possible differential diagnosis with other tumors through dermoscopic examination.

Keywords: Dermoscopy; Histiocytoma, Benign Fibrous; Dermatology

Malignant fibrous histiocytoma (MFH) or undifferentiated pleomorphic sarcoma (UPS) is a sarcoma capable of invading adjacent structures. It is a mesenchymal neoplasia that predominates in men between the sixth and seventh decades of life. It is located mainly in the lower limbs and may affect the head and neck, trunk, and retroperitoneum, presenting a tendency to recurrence and local metastasis. This report aims to present a case of MFH in the ankle of a 49-year-old woman with an adjacent bone invasion, which evolved with transtibial amputation. Clinical, radiological, histopathological, and therapeutic aspects were addressed, highlighting the importance of early diagnosis.

Keywords: Amputation; Malignant fibrous histiocytoma; Sarcoma

Low-grade fibromyxoid sarcoma (LGFS) is a rare, indolent spindle cell sarcoma with a risk of recurrence and metastasis. We report the case of a 34-year-old man with a tumor in his thumb that had recurred after excision eight years ago, with slow and progressive growth. The pathological examination was suggestive of SFBG, and we proceeded with the disarticulation of the phalanx. The patient remains in follow-up, with no evidence of metastases. Although rare, it is essential to recognize the diagnosis of an LGFS with its potential risk of recurrences and metastases, especially as a differential diagnosis of acral soft tissue tumors.

Keywords: Dermatology; Neoplasms; Sarcoma

Extraskeletal Ewing sarcoma (EES) is a rare tumor that affects men between 10-20 years old and represents 25% of Ewing sarcomas. We report a case due to the previous diagnosis of a fast-growing lipoma to highlight the importance of histopathological diagnosis. A 14-year-old boy presented 10x10 cm tumor in the right shoulder for a year with ultrasonography suggesting lipoma. The lesion was excised and EES was confirmed by immunohistochemical analysis. EES diagnosis in young people is challenging compared to subcutaneous tumors, and histopathology is essential. The rapid progression of the tumor and high metastatic rates highlight the significance of early treatment.

Keywords: Sarcoma, Ewing; Neuroectodermal tumors; Sarcoma

Aneurysmal dermatofibroma (ADF) is a rare benign tumor originating in the dermis. It is most common in the lower limbs of women over 30 years. Its etiology is unknown, and histopathological examination confirms the diagnosis. This paper presents a case of ADF with an exuberant presentation in a young female patient with a pedunculated tumor in the right pretibial region, measuring 12 cm in greatest diameter. This report aims to demonstrate an infrequent variant of dermatofibroma with significant growth and emphasize the importance of lesion excision and follow-up because of the high recurrence rate.

Keywords: Histiocytoma, Benign fibrous; Dermatology; Dermoscopy

Fibromyxosarcoma is a rare subtype of soft tissue sarcoma characterized by the presence of spindle cells and myxoid matrix. We report the case of an older patient who presented with progressive growth of a nodule in the interscapular region, and further investigation confirmed the diagnosis of high-grade fibromyxosarcoma. Notably, this neoplasm more commonly occurs in the lower limbs and may exhibit recurrence associated with increased histological grade. Therefore, early diagnosis and treatment are crucial for mitigating morbidity and mortality. We emphasize the significance of diagnosing an atypical case and providing timely therapeutic intervention, contributing to the optimization of clinical outcomes.

Keywords: Sarcoma; Neoplasms, Connective and Soft Tissue; Solitary Fibrous Tumors