Acute hemorrhage from a retroperitoneal liposarcoma treated by embolization

Abstract

Liposarcomas are rare retroperitoneal mesenchymal tumors that present at an advanced stage and often have poor prognoses. These malignant tumors create a diagnostic conundrum and pose several treatment difficulties due to their rarity and anatomic placement. Retroperitoneal liposarcomas often present as asymptomatic abdominal tumors and rarely cause acute bleeding. Surgery is typically required in cases with acute malignant bleeding and hemodynamic instability. Angioembolization and other bleed-control methods should be researched where available. This case report describes the case of a 17-year-old male patient whose tumor had an acute abdominal hemorrhage treated by embolization.

Introduction

The incidence of soft tissue sarcoma is estimated to be 4-5/100,000 annually in Europe, comprising <1% of all malignant tumors in adults. About 10%–15% of adult soft tissue sarcomas are found in the retroperitoneum. Over 50% of retroperitoneal sarcoma and 20% of all soft tissue sarcoma cases are due to the most prevalent form, liposarcoma (LPS) [1]. This tumor type is equally frequent in males and females aged >40-60 years [2]. The World Health Organization classification [3] defines several histological retroperitoneal LPS subtypes: myxoid/round cell LPS, pleomorphic LPS, and well-differentiated and dedifferentiated LPS. About 80% of retroperitoneal sarcomas present as asymptomatic abdominal tumors [4]. Due to the many potential retroperitoneum areas, LPSs in this region can reach relatively large sizes before they start to show symptoms. Therefore a tumor can already be large at diagnosis [5]. However, acute bleeding due to a retroperitoneal LPS is rare. Due to its rarity, the best treatment option for severe abdominal bleeding remains debatable. Endovascular hemostasis might be an efficient means to control bleeding when the tumor type is unknown. This case report discusses a 17-year-old male with a retroperitoneal LPS who presented with acute abdominal hemorrhage.

Case description

A previously healthy 17-year-old male with no relevant family or medical history presented to the Emergency Department after experiencing acute pelvic pain. He was found to be tachycardic (heart rate = 110/min) with stable blood pressure (100/50 mmHg).

Baseline blood tests, including a cross-match, were requested. They showed a hemoglobin content of 105 g/L and a red blood count of 4.11 g/L. His clotting profile was normal. An urgent abdominal computerized tomography (CT) scan was performed, identifying a large 59 × 53 mm lesion (Fig. 1) with an adjacent 73 × 48 mm hematoma pushing the bladder to the right (Fig. 2).

Fig. 1.

Axial pelvic CT images showed a large 50 × 55 mm lesion (A, arrow) with a small pseudoaneurysm (B, arrow).

Fig. 2.

Axial pelvic CT images show an adjacent 73 × 48 mm hematoma (A) pushing the bladder to the right (B).

The patient underwent an emergency angioembolization on the day of admission (Fig. 3).

Fig. 3.

Digital subtraction angiography images show a hypervascular tumor before (A, arrow) and after (B, arrow) embolization.

A percutaneous needle biopsy of the tumor was performed. Histopathology and immunohistochemistry indicated it was a primary retroperitoneal LPS (Fig. 4).

Fig. 4.

Histologic findings of the tumor biopsy in the described patient with LPS. (A) Hematoxylin and eosin staining. (B-F) Immunohistochemistry staining was for positive (B) vimentin (VIM), (C) cyclin-dependent kinase inhibitor 2A (CDKN2A/p16), and (D) cyclin-dependent kinase 4 (CDK4) but negative for (E) cluster of differentiation 34 (CD34) and (F) mucin 4 (MUC4). Images were taken at 40 × magnification.

One week later, the patient underwent an operation using a retroperitoneal approach to the kidney via a left flank incision. Intraoperatively, a large mass was discovered, appearing to originate from the retroperitoneal fat, with a surrounding hematoma. The mass was excised and sent for histology, confirming the tumor to be lipomatous. The patient was referred to our cancer center for continued follow-up. He has not experienced any recurrence in the first 2 postoperative years.

Discussion

About 15% of all sarcomas are retroperitoneal, with an overall incidence of 0.3%-0.4% per 100,000 population [6]. The most frequent sarcoma type developing in the retroperitoneum is LPS (41%), followed by leiomyosarcoma and malignant fibrous histiocytoma [7]. Retroperitoneal LPS accounts for 0.07%-0.2% of all neoplasia cases. LPS can develop in any fat tissue [8]. Approximately 35% of LPS (12%-40%) originate in the retroperitoneum [9].

Most retroperitoneal sarcomas (80%) manifest as asymptomatic abdominal tumors [4]. LPSs in this region frequently reach large sizes before they manifest symptoms due to the retroperitoneum's large potential spaces. When discovered, retroperitoneal sarcomas are often >20 cm in size [5]. Acute hemorrhage caused by a retroperitoneal LPS is rare. Acute bleeding from a retroperitoneal LPS at first presentation can induce hemorrhagic shock. However, such cases are extremely rare and seldom documented in the literature. In a case report published by Martnez-Valls et al. [10] in 1996, the patient underwent emergency surgery that included ipsilateral kidney removal. Al-Sheikh et al. [11] described a comparable case in 2018.

En-bloc resection of nearby viscera is usually necessary because of the challenge of accomplishing completely margin-negative resections. The kidney undergoes segmental resection the most often (36%-80% of cases), followed by the large bowel, pancreas, and spleen (in left-sided tumors) [12]. Other techniques for treating bleeding, such as angioembolization, should be investigated when available. Surgery is usually necessary in cases with acute malignant hemorrhage and hemodynamic instability. Our patient arrived at the hospital with stable hemodynamics. Therefore, we chose to treat the bleeding with angioembolization before pathology determined the sarcoma type and the patient underwent surgery.

Conclusion

Acute abdominal bleeding is an uncommon primary LPS symptom. Surgery is usually necessary in cases with acute malignant hemorrhage and hemodynamic instability. However, alternative techniques for treating bleeding, including angioembolization, should be investigated when available.

Author's contributions

Dau QL and Tran NA contributed equally to this article as first authorship. Dau QL and Tran NA: Case file retrieval and case summary preparation. Dau QL and Nguyen MD: preparation of manuscript and editing. All authors read and approved the final manuscript.

Availability of data and materials

Data and materials used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics approval

Our institution does not require ethical approval for reporting individual cases or case series.

Patient consent

Informed consent for patient information to be published in this article was obtained.