Giant Perineal Solitary Fibrous Tumor: A Rare Case Report

Abstract

Background. Solitary fibrous tumor (SFT) is a fibroblastic mesenchymal tumor that was initially described from the pleura but currently arises at almost every anatomic site. It is usually benign, and surgical resection is curative. SFT involving the perineum is extremely rare. This is the third case report of a perineal SFT in the literature. Case Presentation. We reported an uncommon case of a 64-year-old man presenting with a huge perineal mass that started growing 3 years before his arrival in our service. He was asymptomatic. A contrast-enhanced CT scan revealed a heterogeneous well-circumscribed perineal mass with soft-tissue density. Invasion of the surrounding organs, distal metastasis, and lymph node swelling were absent. The complete resection of mass was done successfully. The specimen was a 23.0 × 14.0 × 8.0 cm encapsulated tumor. Mass weight was 1,170 g. After pathological analysis, we confirmed that the mass was a solitary fibrous tumor. The diagnosis was based on clinical findings and histological morphology and immunohistochemistry study. Conclusion. SFTs are usually indolent tumors with a favorable prognosis. The perineal location is extremely rare. Complete resection of the mass is the treatment of choice.

Perianal Solitary Fibrous Tumor in a Rare Anatomical Presentation: A Case Report and Literature Review

“…However, a perineal location is rare, and to our knowledge, our case is the 4 th reported in the literature. Suster et al, Kim et al, and de Souza Melo et al have reported similar observations [ 4 ]. Therefore, this case report is interesting and useful to avoid misdiagnosis and achieve early treatment.…”

“…Our research revealed more reported cases that refer to the same condition and anatomic region under different names. In this study, we have included all reported cases of perineal, peri-anal, ischiorectal fossa, and ischioanal fossa SFTs ( Table 1 ) [ 4 , 6 , 9 – 18 ]. We excluded cases of pelvic, retroperitoneal, and urinary tract SFTs from our review given the notable differences in their diagnostic and treatment strategies, including the surgical approach.…”

“…A perianal location is rare for this type of tumor. SFTs account for <2% of soft tissue tumors and occur with a similar frequency in both sexes between the 5 th and 7 th decades of life [ 4 , 5 ].…”

A rare solitary fibrous tumor in the ischiorectal fossa: a case report

“…Recent advances in electron microscopy and immunohistochemistry have demonstrated a mesenchymal rather than a mesothelial origin of SFTs. While the majority of SFTs occur within the pleura, approximately 30% of SFTs arise in the peritoneal cavity, retroperitoneal soft tissue, and pelvis [ 1 , 2 ]. However, SFTs occurring in the ischiorectal fossa are extremely rare.…”

“…In unresectable cases, surgical cytoreduction with chemotherapy and radiation therapy might be useful [ 20 , 21 ]. There is no consensus concerning follow-up for SFTs, but continued long-term surveillance is advised due to the indolent nature of the tumor and the possibility of late recurrence up to 20 years after initial treatment [ 1 , 2 ].…”