Intraoperative urothelial carcinoma tumor thrombus embolization to the heart: a case report

ABSTRACT

Urothelial carcinoma (UC) rarely presents with an inferior vena cava (IVC) tumor thrombus. Herein, we report the case of a patient with UC in whom the thrombus embolized to the right atrium during resection. Intraoperative echocardiography identified the large embolus measuring greater than 4 cm and prolapsing through the tricuspid valve. The tumor thrombus was removed via sternotomy. This case is significant for the following learning points: 1) tumor thrombus should be managed with care during removal as it can embolize; 2) intraoperative transesophageal echocardiography is vital in these cases; and 3) a multidisciplinary approach including cardiac surgery is imperative to ensure optimal outcomes.

1. Introduction

Tumor thrombus extending into the inferior vena cava (IVC) is a known complication of renal malignancies, most commonly in renal cell carcinoma (RCC) with an occurrence of 4 to 36% [1,2]. Urothelial carcinoma (UC), another malignancy with renal origin, has been reported in 5–7% of cases that have been associated with tumor thrombosis into the IVC [1]. Generally, tumor thrombi of either UC or RCC in the IVC are accompanied by potentially serious complications, including the risk of embolism to the pulmonary artery (PA) and the heart. Thrombi of any cause that embolize to the right heart are threatening and have been reported with a mortality rate of approximately 28% when treated, and 80–100% when left untreated [3]. Herein, we present the unique case of an intraoperative tumor thrombus embolism of UC to the right atrium and the clinical handling of this complication. This report emphasizes critical aspects of the management, including the role of echocardiography, having cardiac surgery immediately available, and the value of a multidisciplinary approach including cardiac surgery when planning complex resections involving IVC tumor thrombi.

2. Case report

A 71-year-old-male presented with flank pain. His medical profile was significant for hypertension, dyslipidemia, hypothyroidism, diabetes mellitus type 2, and osteoarthritis. Initial investigations including abdominal CT and MRI scans revealed a right renal mass that extended into the inferior vena cava (IVC). A 6.1 × 5.6 × 5.5 cm right upper pole renal mass was found with tumor extending approximately 6 cm into the infrahepatic vena cava, as well as extending into the renal pelvis and proximal ureter (Video 1 in Supplementary Material). Chest CT was unremarkable. Prior biopsy of the renal mass only revealed the presence of malignancy but was unable to further characterize the specimen due to largely non-viable tissue. A multidisciplinary team reviewed the case, and a surgical plan was devised to excise the tumor and thrombus.

The patient underwent a complex operation, including right radical nephrectomy and IVC thrombectomy planned with a urologic oncologist and a vascular surgeon. The surgical approach was midline laparotomy. The kidney, bowel, and liver were mobilized to expose the retroperitoneum. The kidney and entire contents of Gerota’s fascia were mobilized en bloc. The renal artery was ligated. The renal vein and IVC were isolated with the thrombus palpable up to the level of the hepatic veins. In the process of mobilizing the IVC to achieve distal and proximal control, and prior to the placement of a vascular clamp or the application of Pringle Maneuvers, the upper portion of the tumor thrombus was dislodged. Given the speed and subtle nature of embolization, the team was not able to detect an instantaneous change in hemodynamic and respiratory parameters. Nevertheless, intraoperative transthoracic echocardiography (TTE) confirmed the embolization of the thrombus to the right atrium. The patient remained hemodynamically stable.

With full control of the IVC, the infra-hepatic IVC was opened, and the remaining tumor thrombus was removed. The right renal vein ostium was excised, and the IVC was primarily repaired without the need for grafting. The initial operation was concluded, and the patient was transferred to the ICU where transport to the nearest cardiac surgery center was arranged. A pulmonary CT scan was not done since the care team was concerned that the patient could potentially have rapid and unpredictable clinical deterioration. The patient was taken to the cardiac operating room where a transesophageal echocardiogram (TEE) showed a large embolus in the right atrium prolapsing through the tricuspid valve (TV) (Video 2 in Supplementary Material). The embolus was not obstructing blood flow, but it was found to be larger than 4 cm. Thus, a sternotomy was done, followed by bi-caval cannulation, institution of cardiopulmonary bypass (CPB), application of aortic cross-clamp, and antegrade cardiac arrest using blood cardioplegia. The right atrium was opened, and a free-floating mass was noted and removed (Figure 1). The patient was weaned off CPB easily, where cross-clamp and CPB times were 9 min and 26 min, respectively.

Figure 1.

Intraoperative image of tumor thrombus embolized to the right atrium, measuring greater than 4 cm.

The patient’s postoperative course was unremarkable, and he was discharged home on postoperative day 4. Pathology of the right atrial tumor showed poorly differentiated sarcomatoid UC, consistent with the right kidney/IVC pathology results. At 30-days post-surgery, the patient was doing relatively well and able to walk without assistance (Eastern Cooperative Oncology Group (ECOG) performance status 1). Unfortunately, however, the patient had a rapid decline in his status 2-months after surgery. He re-presented to the hospital where repeat imaging revealed multiple new metastatic liver lesions, largest measuring 3.6 × 2.6 cm in the caudate lobe; large recurrent soft tissue mass at the surgical bed measuring 11.1 × 6.3 × 9.4 cm extending into the IVC; and multiple new lung nodules, largest measuring 1.2 × 1 cm in the right lower lobe. The patient elected for palliation. He passed away 3 months after his complex operations

3. Discussion

Thrombectomies of tumor thrombus in the IVC are accompanied by the risk of intraoperative tumor embolism to the heart. The occurrence of this complication is rare but potentially lethal. Generally, thrombi transit to the right heart and can be associated with a high mortality rate [3]. UC occurs in 10–15% of primary renal malignancies and due to the rarity of this condition, it is often misdiagnosed as renal cell carcinoma (RCC) [1,2]. In previous studies, UC was only correctly identified preoperatively in 43% of the cases [1]. The prognosis of patients with UC and IVC involvement is generally poor; as of yet, the optimal surgical and medical management of these patients remains poorly described [4,5]. In the literature, both nephrectomy and nephroureterectomy with simultaneous thrombectomy have been reported [1]. The use of aspiration thrombectomy has been reported in a patient with a sarcomatoid variant of UC where a left renal vein thrombus had embolized to the pulmonary artery [6]. To the best of our knowledge, we report the first case of intraoperative embolization of a sarcomatoid variant of UC. While the paucity of data prevents drawing evidence-based conclusions, it is highly likely that the fragility of the UC tissue contributed to its embolization.

Due to the large size of the tumor thrombus, the tricuspid valve had prolapsed, but the mass had not traversed into the right ventricle or PA. This potentially lethal complication was averted by rapid intraoperative recognition of the tumor thrombus embolization and subsequent emergent cardiac surgical intervention. In this case, TTE was initially utilized to assess the location of the tumor thrombosis as TEE was not available at the index center. For intraoperative diagnosis of tumor thrombus embolization, TEE is considered the gold standard [7]. Indeed, the subsequent TEE confirmed the exact location and size of the tumor thrombosis in the right atrium. Thus, when planning UC or RCC thrombectomies, expertise in using TTE and more importantly TEE are crucial.

This case demonstrates the importance of a coordinated multidisciplinary team, including cardiac surgery available for these complex operations. While a nephrectomy with thrombectomy was initially planned, cardiac surgery was not immediately available on site, and the patient had to be transferred. This highlights an important logistical point: when tumor thrombi are extensive or suspected to be fragile, cardiac surgery should be included in the preoperative planning, and intraoperative stand-by arrangements should be considered. Furthermore, in these unique and high-risk cases, the utility of placing an IVC filter pre-operatively should also be considered.

Based on each individual case, there may also be a role for pulmonary CT scans. Performing this after the first operation may have added further information about potential pulmonary embolism. In this setting and due to the large size and complexity of the tumor thrombus, pulmonary CT would have likely not changed the course of treatment. However, time- and clinical stability-permitting, obtaining a CT scan may be advised.

4. Conclusion

Embolism of renal UC tumor thrombus is a rare but potentially fatal complication. It can result in pulmonary artery embolism, right atrial obstruction, and in the setting of a patent foramen ovale, paradoxical embolism resulting in strokes. Intraoperative embolisms can occur, thus putting the patient under significant risk. This case highlights the importance of intraoperative tumor thrombus handling, the need for immediate access to advanced TEE imaging, and the critical role of a multidisciplinary team including cardiac surgery in managing this complication.

Funding Statement

This paper was not funded.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14796678.2025.2573561.

Article highlights

• Renal urothelial carcinomas are rare, but can have potentially fatal complications.

• Tumors involving the IVC require special consideration with respect to management strategies.

• Multi-modality imaging studies should be used to assess the best surgical approach when managing patients with IVC tumor thrombi.

• Intraoperatively, special care should be given when manipulating tissue planes in patients with IVC tumor thrombi.

• A multidisciplinary approach should be employed when treating patients with IVC tumor thrombi.

• In addition to standard lines and monitors, TEE should strongly be considered in patients with IVC tumor thrombi.

• Patients with IVC thrmobi should be managed in centers that have cardiac surgery on-site.

• To prevent thrombi embolizing proximally, the IVC should be controlled in an expeditious manner in those who have an IVC thrombus and undergoing surgery.

Author contributions

Friederike I Schoettler: Wrote the original manuscript.

Mortaza Fatehi Hassanabad: Data curation and provided a critical review of the manuscript.

Nicole A Webb: Obtained intraoperative imaging and provided critical review of the manuscript.

Jeffery Clark: Provided critical review of the manuscript.

Geoffrey Gotto: Provided critical review of the manuscript.

William T Kidd: Provided critical review of the manuscript.

Ali Fatehi Hassanabad: Conception; data curation; Assisted in the writing of the original draft; and provided critical review of the manuscript.

Disclosure statement

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosure

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Ethical declaration

The patient’s next of kin provided written consent for the preparation and publication of this case report.