Solitary fibrous tumor of the pancreas

Imaging, pathology, and diagnosis of solitary fibrous tumor of the pancreas: A case report and review of literature

BACKGROUND

A solitary fibrous tumor (SFT) is often located in the pleura, while SFT of the pancreas is extremely rare. Here, we report a case of SFT of the pancreas and discuss imaging, histopathology, and immunohistochemistry for accurate diagnosis and treatment.

CASE SUMMARY

A 54-year-old man presented to our hospital with pancreatic occupancy for over a month. There were no previous complaints of discomfort. His blood pressure was normal. Blood glucose, tumor markers, and enhanced computed tomography (CT) suggested a malignant tumor. Because the CT appearance of pancreatic cancer varies, we could not confirm the diagnosis; therefore, we performed endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). Pathology and immunohistochemistry were consistent with SFT of the pancreas. The postoperative pathology and immunohistochemistry were consistent with the puncture results. The patient presented for a follow-up examination one month after discharge with no adverse effects.

CONCLUSION

Other diseases must be excluded in patients with a pancreatic mass that cannot be diagnosed. CT and pathological histology have diagnostic value for pancreatic tumors. Endoscopic puncture biopsy under ultrasound can help diagnose pancreatic masses that cannot be diagnosed preoperatively. Surgery is an effective treatment for SFT of the pancreas; however, long-term follow-up is strongly recommended because of the possibility of malignant transformation of the tumor.

Recurrent malignant solitary fibrous tumor of pelvis: A case report and treatment approach

RATIONALE

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms that typically arise from the pleura but can also occur in various locations throughout the body. Although there are increasingly more reports of extra-pleural SFTs, reports of SFTs in bone are very rare, and a malignant SFT accompanying recurrence of pelvis has not yet been reported.

PATIENT CONCERNS

We herein present the case of a 15-year-old male who experienced intermittent numbness in his right buttock, accompanied by radiating pain in his lower limbs for 6 months. Radiological examinations revealed an expansive, heterogeneous enhanced mass in the sacral and iliac regions, with a branch of the right internal iliac artery feeding the tumor.

DIAGNOSES

The histological examination suggest a diagnosis of a malignant SFT with high proliferation activity.

INTERVENTIONS

The sacral mass was surgically excised.

OUTCOMES

Following the surgery, the patient experienced a local recurrence of the tumor at 9 months and was administered adjuvant imatinib treatment. Recent magnetic resonance imaging contrast-enhanced displayed shrinkage of the tumor, which may provide certain evidence for chemotherapy for the treatment of recurrence of malignant SFTs in the pelvic region.

LESSONS

Complete surgical excision is the recommended treatment for this rare disease entity, and the role of adjuvant therapies is controversial due to their rarity. Our case underscores the challenges in managing recurrent malignant SFTs and highlights the importance of a thorough diagnostic workup. Further research is needed to establish the role of adjuvant therapies in the management of these tumors.

Rare hypervascular pancreatic tumors diagnosed as asynchronous metastases of central nervous system solitary fibrous tumor/hemangiopericytoma

A 70-year-old woman was referred to our hospital for asymptomatic pancreatic tumors. She had a history of hemagiopericytoma (HPC) about 20 years ago, and no apparent recurrence has been observed. Contrast-enhanced computed tomography revealed two hypervascular tumors in the head and uncinate process of the pancreas, and no obvious neoplastic lesions were found in other organs. Endoscopic ultrasound guided fine-needle aspiration cytology was performed and histopathology showed that spindle-shaped tumor cells were arranged in a hemangiopericytoma-like pattern and positive for STAT6, which was a characteristic feature of solitary fibrous tumors (SFTs). Immunohistochemical staining for surgical pathology specimens from past HPC showed positive expression of STAT6, which was Grade 2 central nervous system solitary fibrous tumor/hemagiopericytoma (CNS SFT/HPC) according to the current WHO classification. From these findings, the pancreatic tumors were preoperatively diagnosed as pancreatic metastases of CNS SFT/HPC. She underwent pancreaticoduodenectomy. Histopathological examination of the surgically resected specimen proved that the both pancreatic tumors were SFT/HPC. Thus, pancreatic tumors were finally diagnosed as asynchronous pancreatic metastases from CNS SFT/HPC. Although extremely rare, metastatic pancreatic tumors derived from SFT/HPC should be considered as a differential diagnosis for hypervascular pancreatic tumors, especially when having a past history of brain tumors.