Pleomorphic hyalinizing angiectatic tumor of the mesorectum: a rare case and review of literature

Pelvic retroperitoneal pleomorphic hyalinizing angiectatic tumor: A case report and review of literature

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a rare tumor of the soft tissue, usually located in lower extremities. There are rarely tumors reported in other anatomic locations. Herein, we report retroperitoneal PHAT in a male patient. A 41-year-old man was referred to our clinic due to an incidentally found retroperitoneal mass. Computed tomography (CT) scan showed a solid hypoechoic lesion containing fat component and calcified elements measuring about 80*72*45 mm in the right lower quadrant (RLQ) of the abdomen. Magnetic resonance imaging (MRI) showed circumscribe lesion measuring about 60 x 48 mm with partial enhancement and fat component. In pelvic exploration, a large mass was found that had encased the right external iliac artery and vein. Therefore, the mass and its surrounding iliac vessels were excised and removed en block. Then, the external iliac vessels were reconstructed with Gortex graft. No recurrence was found in 1 month and 3 months post-operation follow up. We report a pelvic retroperitoneal PHAT as a rare location of this tumor. It seems that PHAT must be considered in differential diagnosis in patients with soft tissue tumors in the pelvic cavity.

Pleomorphic hyalinizing angiectatic tumor of the vulva: literature review based on a rare presentation

Pleomorphic hyalinizing angiectatic tumor (PHAT) of soft tissues is a rare, non-metastatic tumor of unknown etiology and uncertain behavior, which may recur locally. There are few reports on this condition, and due to the rarity of the disease, its lineage has not yet been fully elucidated. The present study aims to report the case of an unusual entity observed for the first time in vulval topography. A female patient, 83 years old, presented with a tumor in the vulvar region that had evolved for approximately 4 months. Magnetic resonance imaging showed an expansive perineal formation of 8.5 × 3.5 cm, and a hemivulvectomy with a flap rotation was performed. The review of the slides revealed a mesenchymal lesion without significant atypia, which was richly vascularized. In the areas of interest, the immunohistochemical (IHC) study demonstrated positivity for CD34, estrogen, and progesterone receptors; it was negative for the other tested markers. Morphological findings associated with the IHC staining panel supported the diagnosis of PHAT. The main morphological features of PHAT are clusters of ectatic vessels of different sizes that show deposits of subendothelial and intraluminal fibrin. Fusiform and pleomorphic cells randomly arranged in leaves or long fascicles intermingle these vessels. It is essential to recognize this entity and consider it among the differential diagnoses of a mesenchymal lesion, given the wide variety of entities that comprise this group of lesions.

Pleomorphic Hyalinizing Angiectatic Tumor (PHAT): Review of the Literature with Case Presentation

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a very rare entity of soft tissue considered a "neoplasm of uncertain behaviour of connective or other soft tissue" by the World Health Organization (2020). It develops in subcutaneous tissue of the lower extremities, more frequently in the region of the ankle and foot, and rarely as a deep-seated soft tissue mass in locations such as the perineum, buttock, arms, head and neck, and viscera. Although inconsistent cytogenetic data have been reported on PHAT so far, there are potential morphological and genetic overlaps with hemosiderotic fibrolipomatous tumor (HFLT) and myxoinflammatory fibroblastic sarcoma (MIFS). Here we report a case of PHAT at the level of the upper third of the right thigh in a 48-year-old patient and we also focus on the differential diagnoses of these entities and conduct a literature review of reported cases.