A case of solitary fibrous tumor in the pelvis presenting massive hemorrhage during surgery

Case report: A huge retroperitoneal solitary fibrous tumor closely related to the external iliac vessels misdiagnosed as an ovarian tumor

Background

Solitary fibrous tumor (SFT) is a rare soft tissue tumor originating from mesenchymal cells. Thus far, there have been no reported cases of SFT closely related to the iliac vessels.

Case presentation

An elderly woman was found to have had a lower abdominal mass for more than 20 years. The enhanced computerized tomography (CT) showed a progressively enhanced hypervascular mass. The external iliac blood vessels were closely related to the mass, which was misdiagnosed as an ovarian tumor. During laparotomy, the external iliac vein was seen to penetrate the tumor, and the external iliac artery was seen to penetrate the tumor capsule. The retroperitoneal tumor was diagnosed during the operation. The surgical plan of complete tumor resection, severing of the external iliac arteries and veins, and blood vessel replacement was implemented. Pathological immunohistochemistry showed positive results for STAT6 and CD34, confirming the diagnosis of giant retroperitoneal SFT. The risk is classified as high and requires long-term follow-up. There has been no local recurrence or distant metastasis almost 1 year after surgery.

Conclusion

The incidence of giant retroperitoneal SFT is rare, and the diagnosis can be confirmed through preoperative imaging examination and pathological examination. If the SFT capsule is intact, there is a chance of surgical resection. For SFTs that are penetrated by the iliac blood vessels, adequate preparation must be made before the surgery is performed. Removing the tumor and the iliac blood vessels at the corresponding site and then replacing it with artificial blood vessels is a feasible method with less risk of bleeding. In this case, imaging showed a progressively enhancing hypervascular mass in the lower abdomen, which was related to blood vessels. Preoperative biopsy and pathological testing can confirm the diagnosis. Neoadjuvant therapy or interventional therapy before surgery can shrink the tumor, making the surgical procedure relatively easy with less risk of bleeding.

Solitary fibrous tumor within the mesorectum: literature review based on a case report of resection by transanal minimally invasive surgery (TAMIS)

PURPOSE

Solitary fibrous tumors (SFT) are a rare entity of in majority benign neoplasms. Nevertheless, up to 20% of cases show a malignant tendency with local infiltration or metastasis. Commonly arising in the thoracic cavity, only few cases of SFT of the mesorectal tissue have been reported in the literature. Complete surgical resection, classically by posterior approach, is the treatment of choice. The purpose of this review is to demonstrate the safety and suitability of transanal minimally invasive surgery (TAMIS) as a surgical approach for the resection of benign pararectal solid tumors.

METHODS

We report the case of a 52-year-old man who was diagnosed incidentally with SFT of the distal mesorectum. Resection by TAMIS was performed. Based on this case, we describe the steps and potential benefits of this procedure and provide a comprehensive review of the literature.

RESULTS

Histopathology confirms the completely resected SFT. After uneventful postoperative course and discharge on day four, follow-up was recommended by a multidisciplinary board by clinical examination and MRI, which showed a well-healed scar and no recurrence up to 3 years after resection.

CONCLUSION

SFT of the mesorectum is a very rare entity. To our knowledge, this is the first report on a TAMIS resection for SFT, demonstrated as a safe approach for complete resection of benign pararectal solid tumors.

A multicentre retrospective study on extra-thoracic solitary fibrous tumour: preoperative MRI findings predict intraoperative findings and postoperative prognosis

OBJECTIVE

The present study investigated the relationships between the preoperative and operative findings of solitary fibrous tumour (SFT) and between preoperative findings and prognosis.

METHODS

We reviewed 50 SFT patients treated at our musculoskeletal oncology hospital group. We analyzed preoperative clinical findings, particularly MRI imaging findings, and intraoperative information as well as the relationship between preoperative findings and outcomes.

RESULTS

Mean age was 48.9 years and the mean follow-up was 51.8 months. Prior to surgery, needle biopsy was performed on 27 patients and open biopsy on 14. T2-weighted images showed a high signal intensity in 24 patients and heterogeneous signal intensity in 20. Tumours had polylobular contours in 17 patients and smooth and round contours in 27. Collateral feeding vessels were detected in 22 patients. Gd-enhanced MRI was performed on 23 patients, and showed 15 with homogeneous enhancement and 8 with heterogeneous enhancement. Surgical times were significantly longer in patients with a retroperitoneal origin, a tumour of 10 cm or more, and polylobular-type tumours. Intraoperative blood loss was significantly greater in patients with a retroperitoneal origin and heterogeneous Gd-MRI-enhanced tumours. In histopathological evaluations, surgical margins were positive in 12 patients. Local recurrence was observed in one patient. Distant metastasis was noted in eight patients, four of whom had pulmonary metastases. Positive surgical margins were more common in polylobular-type tumours. Distant metastases were more likely to appear in patients with observable collateral feeding vessels and heterogeneous Gd-MRI enhancement.

CONCLUSION

The present results suggest that preoperative clinical findings in SFT patients predict longer surgical times and the risk of increased intraoperative blood loss. Moreover, the risk of a positive surgical margin and postoperative distant metastases may be predicted based on preoperative MRI.

A case of a large solitary fibrous tumor arising from the retroperitoneum resected completely using an intra-aortic balloon

Solitary fibrous tumors (SFTs) are rare mesenchymal cell-derived tumors that can cause substantial bleeding during surgery due to hyper-vascularization. We report a case of a large retroperitoneal SFT resected completely using an intra-aortic balloon. A 71-year-old female with a history of type 2 diabetes mellitus presented with a tumor that was diagnosed as an insulin-like growth factor-II-producing benign SFT using computed tomography-guided biopsy. The tumor had grown from 6 to 20 cm in diameter within 4 years, with concurrent and severe hypoglycemia. Preoperative computed tomography findings showed substantial blood flow toward the tumor. The retroperitoneal tumor was observed to be widely attached. Substantial hemorrhaging during tumor resection was observed despite vascular embolism. We inflated the intra-aortic balloon for 45 min and resected the tumor completely. In conclusion, large SFT resection requires preoperative tumor blood flow evaluation and preparation of both a vascular embolism and an intra-aortic balloon.

Postoperative Morbidity After Radical Resection of Retroperitoneal Solitary Fibrous Tumor

Background

This study aimed to investigate the clinicopathological characteristics of retroperitoneal solitary fibrous tumor (RSFT) and the safety of radical resection.

Methods

A retrospective analysis was conducted on the data of 32 RSFT patients who received surgery with curative intent from February 2011 and June 2021.

Results

This cohort included 16 (50%) male and 16 (50%) female patients, with the median age of 52 (29 to 72) years. Tumor burden ranged from 3 to 25 (median, 10) cm. Seven patients received arterial embolization before surgery. 15 (47%) patients received radiotherapy, nine (28%) of which received preoperative radiotherapy. Most of the patients (91%) achieved complete resection with median bleeding of 400 (20 to 5,000) ml. Nine (28%) patients received packed red blood cell (RBC) transfusion, with a median of 5 (2 to 10) U. All patients had the five-year progression-free survival rate and the overall survival rate of 75.8% and 80.0%, respectively. 11 (34%) patients were found with adverse events, and four (12%) patients were found with serious postoperative complications (Clavien-Dindo ≥3), of which one (3.1%) patient died after surgery. The univariate analysis found that tumor burden (p = 0.022), packed RBC transfusion (p = 0.001) and postoperative hospital stays (0.027) were correlated with overall morbidity. The multivariate analysis found packed RBC transfusion as an independent risk factor for postoperative morbidity (HR 381.652, 95% CI, 1.597–91213.029, p = 0.033).

Conclusion

RSFT was confirmed as an uncommon, slow-growing and recurring tumor, with acceptable postoperative morbidity and mortality after surgical resection.

Transcatheter arterial embolization of malignant pelvic solitary fibrous tumor: case report and literature review

Pelvic malignant solitary fibrous tumor (SFT) is a relatively rare disease, and literature on radical resection with transcatheter arterial embolization of pelvic SFT is lacking. In this work, we report on a 55-year-old man with a presacral mass who was hospitalized at our department. Computed tomography and magnetic resonance imaging indicated pelvic space-occupying lesions that were 12 cm × 10 cm in size and pelvic lesions that were not clearly demarcated from the right posterior wall of the bladder and the right ureter. This result suggested severe secondary hydronephrosis of the right renal pelvis. The patient underwent transcatheter iliac arterial embolization. Radical tumor resection was performed, and the results of pathological examination confirmed the diagnosis of malignant pelvic SFT. There was no SFT recurrence in this patient at 1-year follow-up. Herein, we report on the treatment of a patient with malignant pelvic SFT, a rare condition, who underwent successful radical resection after transcatheter arterial embolization. Transcatheter arterial embolization can block the blood supply of the SFT as much as possible and improve the possibility of tumor resection. In the future, pelvic SFTs can be considered improving the resection rate by transcatheter arterial embolization before surgery.

Solitary fibrous tumors: Clinical and imaging features from head to toe

Solitary fibrous tumors (SFTs) are rare fibroblastic mesenchymal tumors that are usually benign with variable malignant potential. They can develop in any organ due to their spindle cell origin. The exact etiology of solitary fibrous tumors is unknown. The majority of SFTs are benign with 10-30% of them exhibiting aggressive and malignant features. The aggressiveness of this type of tumor is not associated with its histological features, which makes surgical resection the treatment of choice. We will review the clinical and radiological features and possible differential diagnoses of SFTs according to their anatomical sites following the World Health Organization 2020 classification.

[Treatment of a patient with giant solitary fibrous tumor of the left hip]

The authors report surgical treatment of a 59-year-old female with a giant solitary-fibrous tumor of the left hip. Previous excision of hip hemangioma was performed in 2016. Recurrent tumor with fast growth has occurred since 2018. The neoplasm consisted of 2 tumors connected by vascular structures. CT revealed soft tissue neoplasms in the upper third of the left thigh (anterior, medial and dorsal regions). Large tumors with an isthmus along the inner surface had tuberous contours and internal septa. The last ones and walls accumulated contrast agent. No structural damage to femoral muscles was observed. The patient underwent resection of tumor and vascular ligation (great saphenous vein and its tributaries along the anterior surface, arteries from the deep femoral artery system along the posterior surface of tumor). There were no early postoperative complications. There are no complaints within 6 month after surgery. There is no lower limb dysfunction.

An abdominal-sacral approach with preoperative embolisation for vulvar solitary fibrous tumour: a case report

Background

Solitary fibrous tumours (SFTs) in the female genital tract are uncommon. Resection of these tumours is controversial because it can cause life-threatening haemorrhage. We report a case of vulvar SFT that was excised in a combined abdominal-sacral approach after preoperative embolisation.

Case presentation

At another hospital, an inoperable intrapelvic tumour was diagnosed in a 34-year-old woman. Computed tomography and magnetic resonance imaging showed that the uterus, urinary bladder and rectum were compressed laterally by a pelvic tumour with a maximum diameter of 11 cm. This mass was hypervascular and had a well-defined border. Transperineal biopsy was performed, and immunostaining revealed that the mass was an SFT. The tumour was supplied by feeding vessels from the right iliac arteries. First, we embolised the feeding vessels. Second, we performed surgical resection in a combined abdominal-sacral approach; no blood transfusion was necessary, and no perioperative complications occurred. The final pathological diagnosis was SFT that was positive for CD34 and signal transducer and activator of transcription 6 according to immunohistochemical staining.

Conclusion

During a year of follow-up, the disease did not recur. Treatment of pelvic SFT should aim at complete resection through various approaches after careful measures are taken to prevent haemorrhage.

Solitary fibrous tumor with atypical features of the paravesical space: benign clinical course at the 10-years follow-up. Report of a case and review of the literature

Extra-pleural solitary fibrous tumor (SFT) is a relatively rare soft tissue neoplasm, with only rare cases reported in the pelvic cavity. Most SFTs are histologically benign, with only a few malignant cases reported in the literature so far. We report a rare case of SFT arising in the paravesical space of a 79-year-old man. Histologically the tumor corresponds to an “intermediate risk tumor” according to a risk stratification scheme for metastatic potential, which incorporates patient age, tumor size, mitotic activity and necrosis. Notably tumor showed a benign clinical course without evidence of local recurrence after a 10-years follow-up. Tumor was composed of both spindle and epithelioid cells variably set in a fibro-myxoid stroma, with focal pleomorphic, necrotic and highly mitotic (> 4 mitoses/10HPF) areas. Immunohistochemistry, showing a diffuse CD34 and STAT6 immunoreactivity, supported the diagnosis of SFT. The present case emphasizes that the clinical course of the pelvic SFTs with atypical morphological features is unpredictable on the basis of morphology alone, and thus the term “SFT with atypical features, including the risk stratification class” should be preferred to “malignant SFT”.

A giant pelvic solitary fibrous tumor with Doege-Potter syndrome successfully treated with transcatheter arterial embolization followed by surgical resection: a case report

Background

Solitary fibrous tumor (SFT), a mesenchymal fibroblastic tumor with a hypervascular nature, rarely develops in the pelvis. Resection of a giant SFT occupying the pelvic cavity poses an increased risk of developing massive hemorrhage during resection, although surgical resection is the most effective treatment method for this tumor to achieve a potential cure. SFT rarely develops with Doege–Potter syndrome, which is known as a paraneoplastic syndrome characterized by non-islet cell tumor hypoglycemia (NICTH) secondary to SFT that secretes insulin-like growth factor-II (IGF-II). We present a case of a giant pelvic SFT with Doege–Potter syndrome, which was successfully treated with transcatheter arterial embolization (TAE) followed by surgical resection.

Case presentation

A 46-year-old woman presented with a disorder of consciousness due to refractory hypoglycemia. Images of the pelvis showed a giant and heterogeneously hypervascular mass displacing and compressing the rectum. Endocrinological evaluation revealed low serum levels of insulin and C-peptide consistent with NICTH. Angiography identified both the inferior mesenteric artery and the bilateral internal iliac artery as the main feeders of the tumor. To avoid intraoperative massive bleeding, super-selective TAE was performed for the tumor 2 days prior to surgery. Hypoglycemia disappeared after TAE. The tumor was resected completely, with no massive hemorrhage during resection. Histologically, it was diagnosed as IGF-II-secreting SFT. Partial necrosis of the rectum in the specimen was observed due to TAE. The patient was followed up for 2 years and no evidence of disease has been reported.

Conclusions

Preoperative angiography followed by TAE is an exceedingly helpful method to reduce intraoperative hemorrhage when planning to resect SFT occupying the pelvic cavity. Complications related to ischemia should be kept in mind after TAE, which needs to be planned within 1 or 2 days before surgery. TAE for tumors may be an option in addition to medical and surgical treatment for persistent hypoglycemia in Doege–Potter syndrome.

Solitary fibrous tumor arising from pelvic retroperitoneum: A report of two cases and a review of the literature

Solitary fibrous tumors (SFT) rarely arise in the pelvis. Here, we report two cases of SFT arising from the pelvic retroperitoneum. The first case involves a 64-year-old woman diagnosed with a 5-cm pelvic mass. Magnetic resonance imaging revealed a solid and cystic mass with marked enhancement, but limited water restriction. During surgery, intraligamental tumor arising near the round ligament was resected. Pathologically, the tumor comprised dilated vessels and spindle-shaped cells positive for STAT6 and CD34. The second case involves a 53-year-old woman diagnosed with a 4.5-cm pelvic mass through computed tomography. Magnetic resonance imaging demonstrated a solid mass with multiple cysts with strong enhancement and slight water restriction. During surgery, the tumor was found in the retroperitoneum. Pathologically, spindle-shaped tumor cells positive for STAT6 and CD34 had proliferated around the prominent hyalinized vessels. Although rare in the pelvis, SFT should be suspected when a mass with strong enhancement is found.

Giant Perineal Solitary Fibrous Tumor: A Rare Case Report

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.

Integrally calcified solitary fibrous tumor in the retroperitoneum: a case report and review of the literature

Solitary fibrous tumor (SFT) is a rare stromal neoplasm and usually occurs in the thoracic cavity. We here report a case of retroperitoneal SFT with prominent calcification. A 64-year-old man presented with an incidentally detected retroperitoneal mass in the right upper abdomen. Imaging tests indicated an integrally calcified mass. The lesion was observed for 2 years and laparoscopically resected according to the patient's wish. Microscopically, the mass was mostly occupied by calcification and proliferous spindle cells were scattered with positive CD34 expression. We diagnosed morphologically benign SFT and the patient remained disease-free 1 year after the excision. There has been no report of such integrally calcified SFT. Retroperitoneal SFT is difficult to make a preoperative diagnosis, and careful follow-up after the excision is recommended because morphological malignancy does not always correspond to clinical malignancy.

Giant solitary fibrous tumor of the pelvis successfully treated with preoperative embolization and surgical resection: a case report

Solitary fibrous tumors (SFTs) rarely develop in the pelvis. When they do arise, they are usually treated using surgery, although SFTs are often very large by the time of diagnosis, which makes surgical excision difficult. We report a case of a 63-year-old man who was referred to our hospital for the treatment of a giant tumor of the pelvis. Computed tomography (CT) revealed a 30 × 25 × 19 cm sized hypervascular tumor that almost completely filled the pelvic cavity. The diagnosis of SFT was made by CT-assisted needle biopsy. The feeding arteries of the tumor were embolized twice. The first embolization aimed to reduce the tumor volume, while the second one was planned a day prior to the surgery to obtain hematostasis during the operation. Tumor resection was then performed. The blood loss during the operation was 440 ml, and there was no uncontrollable bleeding. The postoperative course was uneventful. No recurrence of SFT was observed during a 2-year follow-up.