Dados do Trabalho

Título

Angiomatoid histiocytoma on the back: knowing the enemy

Apresentação do caso

We report the case of a 51-year-old female patient submitted to an oncological resection of a lesion in the dorsal region on the left and diagnosed with superficial angiomatoid fibrous histiocytoma.

Discussão

Malignant fibrohistiocytoma (FHM) is a rare tumor that can be found in any organ that derives from the mesenchymal tissue. The World Health Organization (WHO) has been changing the classification of fibrohistiocytic tumors in recent years. The ones currently present as intermediate and malignant are plexiform fibrohistiocytic tumor, soft tissue giant cell tumor and malignant tenosynovial giant cell tumor. The histogenesis of this type of tumor is still debatable, as in most cases the histiocytic component is actually non-neoplastic. However, in the presence of neoplasia, the histiocytic element contributed to the development of the lesion. With the new classification released by the WHO in 2020, the FHM started to be recognized as a purely fibroblastic tumor, identified by the original name of myxofibrosarcoma. The so-called inflammatory FHM overlap with the inflammatory variant of dedifferentiated liposarcomas and the angiomatoid FHM, often associated with the EWSR1-CREB1 gene, is currently listed in the group of soft tissue injury of unknown differentiation. FHMs commonly appear as fast-growing nodules in the soft tissues of the extremities and bones in patients between the 5th and 7th decade of life, they can be superficial, when above the fascia, or deep. In invasive tumors that go beyond the fascia, a recurrence is common, with distant metastasis rates reaching up to 40% of cases, with the lung being the most affected site. Wide resection is recommended due to the high degree of local recurrence, around 45%. Neoadjuvant and adjuvant therapy has little or no benefit in treating this condition.

Comentários Finais

Malignant angiomatoid histiocytoma is rarely reported in the literature, but it should not be excluded as a differential diagnosis of soft tissue neoplasms. Due to the rarity of this neoplasm, the atypical location and the short period of clinical follow-up, the natural course of the history of this tumor has not yet been elucidated; which makes this account valuable.

Palavras Chave

Angiomatoid histiocytoma; rare disease