Management of a retrorectal lipomatous hemangiopericytoma by preoperative vascular embolization and a multidisciplinary surgical team: report of a case

Laparoscopic resection of a neuroendocrine tumor that almost fully replaced tailgut cysts: a case report

Background

Neuroendocrine tumors (NETs) originate from neuroendocrine cells, which are found throughout the body. NETs occur principally in the gastrointestinal tract (approximately 65%) and bronchopulmonary tract (approximately 25%) but rarely occur in the presacral space. Aside from primary and metastatic lesions, there have been reports of NETs occurring in the presacral space arising from tailgut cysts, teratomas, and imperforate anus. We herein report a rare case of laparoscopic resection of a NET in the presacral space, which almost fully replaced tailgut cysts.

Case presentation

A 68-year-old woman was referred to our hospital for surgery of a right inguinal hernia, but preoperative computed tomography revealed an asymptomatic 43-mm mass in the presacral space. Magnetic resonance imaging showed a multilocular solid mass with clear boundaries and a slightly high signal intensity on T1- and T2-weighted images. Positron emission tomography showed 18F-fluorodeoxyglucose uptake. Thus, we suspected a malignant tumor and performed laparoscopic resection to obtain a definitive diagnosis. Macroscopically, the tumor was 43 mm in size with clear boundaries, and the cut surface was a gray-white solid component. Histopathological findings revealed that the tumor was composed of relatively uniform cells with fine chromatin, with round to oval nuclei arranged in solid, trabecular, or rosette-like growth patterns. Small cysts lined with stratified squamous epithelium and columnar epithelium were observed along with solid components of the tumor, which is a feature of tailgut cysts. Therefore, the final diagnosis was NET Grade 1 arising from tailgut cysts. No recurrence was observed within 1 year after surgery.

Conclusions

We performed en bloc laparoscopic resection of a NET arising from tailgut cysts in the presacral space without injury. In cases of a solid lesion in the presacral space, not only the primary disease but also the pathological condition with tissue transformation and replacement should be considered, as in this case.

Large hemangiopericytoma of the pelvis--towards a multidisciplinary approach

Background

In 1942, Stout described tumors which derive from Zimmerman’s pericytes and suggested the term hemangiopericytoma (HPC). These tumors, which are often highly vascularized, pose difficulties in the surgical management regarding blood loss and complete resection. Therefore, preoperative management seems to be an essential part in dealing with these issues.

Case presentation

We present a 70-year-old female patient with a large HPC in the pelvis. Preoperative embolization of the tumor was performed, and 2 weeks after the intervention, we completely resected the tumor with minimal blood loss.

Conclusion

In which cases do we need preoperative treatment, especially emboliziation of hemangiopericytomas/solid fibrous tumors (SFT)? Although preoperative embolizations of tumors are now commonly undertaken, as for now, neither a clear statement nor a standardized approach has been given or developed. The purpose of this article is to provide our experience with preoperative embolization and to start a new discussion concerning a standardized approach.

Surgical treatment of retrorectal (presacral) tumors

Retrorectal (also known as presacral) tumor (RT) is a rare disease of retrorectal space. They can be classified as congenital, inflammatory, neurogenic, osseous, or miscellaneous. The most common presentation is an asymptomatic mass discovered on routine rectal examination, but certain nonspecific symptoms can be elicited by careful history and physical examination. The primary and only satisfactory treatment is surgery for RTs. Three approaches commonly used for resection are abdominal, transsacral, or a combined abdominosacral approach. Prognosis is directly related primary local control, which is often difficult to achieve for malignant lesions.

Fat-forming variant of solitary fibrous tumour of the pleura: CT findings

The fat-forming variant of solitary fibrous tumour (SFT) was previously called lipomatous haemangiopericytoma and is a rare variant of solitary fibrous tumour. It predominantly occurs in the deep soft tissues of the retroperitoneum and thigh. Only a handful of cases involving the perineum, spine, thoracic wall and pelvic cavity have been reported in the radiological literature and the fat-forming variant of SFT involving the pleura has not been previously reported. Herein, we report the CT findings of a case of the fat-forming variant of SFT involving the pleura that was treated by excision. Chest CT showed a large lobulated heterogeneous fatty mass with a multifocal enhancing soft-tissue component in the left lower hemithorax. Although rare, the fat-forming variant of SFT of the pleura should be added to the differential diagnosis of fat-containing pleural soft-tissue tumours.

Lipomatous hemangiopericytoma of the stomach: A case report and a review of literature

Lipomatous hemangiopericytomas (LHPCs) are rare soft-tissue tumors that are histologically characterized by hemangiopericytomatous vasculature and the presence of mature adipocytes. We present the clinicopathological features of a case of gastric LHPC in a 56-year-old female, along with a literature review. Endoscopy and endoscopic ultrasound showed a submucosal tumor 0.8 cm across in the greatest dimension in the lesser curvature side of the gastric antrum. Grossly, the well-defined mass had a solid and tan-white cut surface admixed with myxoid regions and yellowish areas. Histological examination revealed a submucosal well-circumscribed lesion composed of cellular nodules with the classic appearance of an hemangiopericytoma admixed with clusters and lobules of mature adipocytes. The ill-defined tumor cells had weakly eosinophilic cytoplasm and contained spindled nuclei with occasional small nucleoli. Nuclei atypia and mitoses were absent, and no cellular atypia, necrosis or vascular invasion was observed. Immunohistochemistry showed that the tumor cells were diffusely positive for CD34, CD99, and vimentin and were focally reactive for bcl-2. This is the first known report of an LHPC in the stomach. The patient was followed for 12 mo without any evidence of metastasis or recurrence.

Retrorectal tumors

Tumors that arise in the retrorectal (presacral) space are uncommon lesions that present with nonspecific signs and symptoms, which lead to difficult diagnoses. For complete evaluation of the lesion, cross-sectional imaging is required to determine the extent of resection and the appropriate surgical approach. Surgical removal leads to favorable outcomes for patients with benign purely cystic retrorectal tumors. Preoperative tissue diagnosis with transperineal and transsacral biopsies of solid or heterogeneous cystic lesions, are essential to determine the necessity of neoadjuvant therapy, which may decrease local recurrence after surgery and avoid an unnecessary delay in systemic therapy.

Rectal hemangiopericytoma in a 37-year-old woman: a case report and review of the literature

Introduction

Hemangiopericytoma is an uncommon perivascular tumor. Rectal Hemangiopericytomas are extremely rare. To the best of our knowledge, only two cases have been reported in the literature.

Case presentation

We report the case of a 37-year-old Asian woman with an Hemangiopericytoma rising from the anterior wall of her rectum. Abdominopelvic computed tomography showed a 7.4 cm solid mass between her uterus and her rectum. Heterogeneous gradual enhancement after intravenous injection of contrast material was noted with several tortuous vessels around her tumor. Intra-operative findings indicated a capsule and well-circumscribed solid tumor connecting with the anterior wall of her rectum by a small pedicle. With immunohistochemical stains, her tumor cells reacted positive for Bcl-2, CD34, and ki67 and negative for CD10, CD117, S100, and Desmin. Follow-up computed tomography scans have shown no tumor recurrence or metastasis signs.

Conclusions

Rectal Hemangiopericytoma is a rare tumor with non-specific imaging findings. Hemangiopericytomas should be included in the differential list when a massive tumor with heterogeneously gradual enhancement in the regions of the rectum is encountered.