ABSTRACT
Introduction
Intraoperative tumor thrombus embolization during renal cell carcinoma (RCC) surgery with inferior vena cava (IVC) tumor thrombus is a rare but potentially fatal complication. We report successful emergency cardiac surgery for massive pulmonary artery tumor embolism.
Case Presentation
A 75‐year‐old female with left RCC and IVC tumor thrombus underwent radical nephrectomy. Pre‐existing left pulmonary artery tumor embolism was noted preoperatively. During IVC manipulation, the tumor thrombus dislodged and migrated through the right heart to completely occlude the right pulmonary artery, causing cardiac arrest. Through multidisciplinary collaboration, nephrectomy was completed under cardiac massage, followed by emergency cardiopulmonary bypass and pulmonary artery thrombectomy. The patient recovered completely without neurological sequelae.
Conclusion
This case demonstrates the critical importance of preoperative risk assessment, intraoperative transesophageal echocardiography monitoring, and immediate multidisciplinary decision‐making in managing this life‐threatening complication. The “double hit” mechanism of pre‐existing and acute pulmonary embolism significantly worsened the clinical course.
Keywords: emergency cardiac surgery, multidisciplinary team, pulmonary embolism, renal cell carcinoma, tumor thrombus
Keynote Message
This case demonstrates that renal cell carcinoma with inferior vena cava tumor thrombus can cause catastrophic intraoperative pulmonary embolism, even with Level II thrombi traditionally considered low‐risk. Pre‐existing pulmonary embolism serves as a critical warning sign of thrombus fragility, warranting enhanced preventive measures such as temporary IVC filter placement. Real‐time transesophageal echocardiography monitoring and immediate multidisciplinary response are essential for patient survival. These lessons can help urologists and cardiac surgeons prevent and manage this life‐threatening complication.
1. Introduction
Renal cell carcinoma (RCC) with inferior vena cava (IVC) tumor thrombus occurs in 4%–10% of cases [1]. Intraoperative tumor thrombus embolization is rare but potentially catastrophic, with mortality rates as high as 60% [2]. The risk is elevated when tumor thrombus extends to Level III‐IV [3, 4].
Pre‐existing pulmonary artery embolism (PAE) from tumor thrombus fragments reduces pulmonary reserve and increases the risk of acute right heart failure if additional embolic events occur [5]. We report a case where pre‐existing left PAE combined with intraoperative right PAE created a “double hit” scenario, leading to cardiac arrest but successful rescue.
2. Case Presentation
A 75‐year‐old female with hypertension and diabetes was referred for surgical management of left RCC with IVC tumor thrombus after failed systemic therapy with pembrolizumab plus lenvatinib and cabozantinib. Preoperative imaging revealed a 5.3‐cm left renal mass with Level II tumor thrombus extending from the left renal vein into the IVC. Critically, contrast‐enhanced CT demonstrated pre‐existing tumor embolism occluding the left pulmonary artery main trunk (Figure 1A–D). Cine MRI showed the IVC tumor thrombus was mobile without wall adherence (Figure 1E,F). Pulmonary perfusion scintigraphy confirmed severely impaired left lung perfusion (Figure 2A).
FIGURE 1.
Preoperative imaging findings. (A) Contrast‐enhanced CT showing tumor embolism occluding the left pulmonary artery main trunk. (B) Tumor thrombus extending from left renal vein into inferior vena cava (IVC portion). (C) Tumor thrombus extending from left kidney into left renal vein (renal vein portion). (D) Tumor thrombus extending from left renal vein into IVC (coronal view). E. Cine MRI evaluation of IVC tumor thrombus (expiratory phase). (F) Cine MRI evaluation of IVC tumor thrombus (inspiratory phase). The IVC wall moves independently from the tumor thrombus with respiration, indicating lack of tumor thrombus adherence to the IVC wall (arrowheads indicate the tumor thrombus).
FIGURE 2.
Pulmonary perfusion scintigraphy. (A) Preoperative, (B) Postoperative. Preoperatively, left lower lobe perfusion was severely impaired (arrowhead indicates the area of poor blood flow), but improved postoperatively following intraoperative left pulmonary artery tumor thrombus removal. Right lung perfusion remained good both pre‐ and postoperatively.
The clinical diagnosis was left RCC with IVC tumor thrombus and left pulmonary artery tumor embolism (cT3bN0M0, Stage III). After multidisciplinary consultation including the cardiac surgery team, we decided to prioritize radical nephrectomy despite the pre‐existing PAE, as the patient was completely asymptomatic and hemodynamically stable despite the near‐complete left pulmonary artery occlusion, with the pre‐existing pulmonary embolism to be managed expectantly.
Radical left nephrectomy with IVC tumor thrombectomy was performed under general anesthesia with continuous transesophageal echocardiography (TEE) monitoring. The left renal artery was ligated first. IVC dissection proceeded with taping above the tumor thrombus cranial end and below both renal veins, followed by posterior IVC dissection with lumbar vein ligation.
To secure the IVC for clamping, manual dissection of the dorsal aspect of the IVC was performed, followed by ligation of the lumbar veins. To confirm that a Satinsky clamp could be safely placed on the cranial side of the tumor thrombus, a milking‐like maneuver was performed to gently push the cranial edge of the thrombus caudally. The tumor thrombus was palpable in the surgical field. However, while preparing for the next step, the palpable tumor thrombus suddenly disappeared. Immediate TEE examination revealed a large tumor thrombus floating freely in the right atrium (Figure 3A,B and Video S1). Emergency consultation between teams was convened. Since the tumor thrombus remained in the right atrium without immediate hemodynamic compromise, the strategic decision was made to complete nephrectomy rapidly before cardiac intervention.
FIGURE 3.
Intraoperative transesophageal echocardiography findings. (A) Tumor thrombus in right atrium (diastolic phase). (B) Tumor thrombus in right atrium (systolic phase). (C) Tumor thrombus migrated to right pulmonary artery (arrowheads indicate the tumor thrombus).
However, during continued nephrectomy, TEE monitoring showed the tumor thrombus migrating through the right ventricle to completely occlude the right pulmonary artery (Figure 3C and Video S2). At 43 min after tumor thrombus dislodgement, the patient developed severe hypotension, decreased end‐tidal CO2, and pulseless electrical activity. External cardiac massage was immediately initiated while nephrectomy was completed within 50 min of tumor thrombus dislodgement (Figure 4A,B).
FIGURE 4.
Resected specimens and postoperative contrast‐enhanced CT findings. (A) Left nephrectomy specimen (renal vein side). The torn end of the IVC tumor thrombus is visible (arrowhead indicates the torn end). (B) Left nephrectomy specimen (renal parenchyma side). (C) Tumor thrombus removed from the right pulmonary artery. (D) Postoperative contrast‐enhanced CT findings. The tumor thrombus that existed in the left pulmonary artery main trunk has been removed (arrowhead indicates the recanalized left pulmonary artery).
CPB was established 61 min after tumor thrombus dislodgement. Pulmonary artery incision revealed a tumor thrombus completely occluding the right pulmonary artery, which was successfully removed (Figure 4C). The pre‐existing left pulmonary artery thrombus was also extracted. Aortic unclamping occurred at 104 min, CPB weaning at 115 min. On the Bispectral Index (BIS) monitoring system, BIS showed 0 during cardiac massage interruption but recovered promptly after CPB establishment.
Pathological examination revealed chromophobe RCC with sarcomatoid change (WHO/ISUP Grade 4) with adrenal metastasis (pT3cM1). The patient was extubated on postoperative day 1 without neurological deficits. Postoperative imaging confirmed complete right pulmonary artery recanalization and improved left lung perfusion (Figures 2B, 4D). She was discharged after 1 month.
3. Discussion
This case demonstrates the “double hit” mechanism in RCC surgery complicated by pre‐existing PAE. Pre‐existing left PAE had severely compromised pulmonary reserve. When the right pulmonary artery became occluded, virtually all pulmonary circulation was eliminated, causing cardiac arrest. This contrasts with Roberts et al.'s case without pre‐existing PAE, where intraoperative tumor embolism caused hypotension but not cardiac arrest [6].
First, the mechanism of thrombus dislodgement warrants consideration. Manual dissection of the IVC and a milking‐like maneuver to confirm the clamping site were performed. Although these are standard procedures, they may have applied cumulative mechanical stress to an intrinsically fragile thrombus. The dislodgement during surgical standby suggests prior maneuvers may have caused microscopic damage, leading to delayed fragmentation.
Second, preoperative risk assessment is paramount. The pre‐existing left pulmonary artery embolism was the most critical indicator of the thrombus's intrinsic fragility. The preoperative finding of mobile tumor thrombus on cine MRI proved paradoxical—while mobility suggested easier surgical removal without requiring complex IVC reconstruction [7], it simultaneously indicated higher embolization risk. Poor contrast enhancement on preoperative CT suggesting non‐clear cell histology should have raised suspicion for thrombus fragility. The final diagnosis of chromophobe RCC is significant, as this subtype is associated with friable tumor tissue, increasing embolization risk. The pre‐existing pulmonary embolism was direct evidence of spontaneous thrombus fragmentation, indicating extremely high risk during surgical manipulation.
Third, preventive strategies must be stratified by tumor thrombus level. For high‐level (III‐IV) thrombi, aggressive strategies such as cardiopulmonary bypass with deep hypothermic circulatory arrest are often necessary [8]. However, for Level II thrombi, less invasive preventive measures should be prioritized in high‐risk cases. Prophylactic temporary IVC filter placement above the thrombus should have been considered. Given multiple high‐risk features—pre‐existing pulmonary embolism, mobile thrombus, poor contrast enhancement, and systemic therapy resistance—the threshold for IVC filter placement should have been low.
Finally, we must address the decision not to surgically remove the pre‐existing left pulmonary embolism preoperatively. This decision was made in consultation with the cardiac surgery team based on the patient's asymptomatic status and stable hemodynamics to avoid morbidity from thoracotomy and bypass. However, in retrospect, given systemic therapy resistance and multiple high‐risk features, a planned single‐stage operation with preoperative preparation for cardiopulmonary bypass to address both the primary tumor and pulmonary embolism would have been more prudent. This case demonstrates that in patients with pre‐existing pulmonary embolism and high‐risk tumor thrombus features, the threshold for planned cardiopulmonary bypass should be lower, even in asymptomatic patients.
4. Conclusion
Intraoperative pulmonary artery embolism during RCC surgery requires comprehensive preoperative risk assessment and multidisciplinary preparation. This case demonstrates that even in catastrophic situations, accurate situational awareness through TEE monitoring, strategic decision‐making by multidisciplinary teams, and coordinated surgical techniques can achieve patient salvation. Pre‐existing PAE significantly increases the risk of acute circulatory collapse and should prompt enhanced perioperative management strategies.
Consent
Written informed consent was obtained from the patient for publication of this case report and accompanying images.
Conflicts of Interest
The authors declare no conflicts of interest.
Supporting information
Video S1: Intraoperative transesophageal echocardiography showing tumor thrombus in the right atrium (Figure 3A,B).
Video S2: Intraoperative transesophageal echocardiography showing tumor thrombus occluding the right pulmonary artery (Figure 3C).
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
References
- 1. Psutka S. P. and Leibovich B. C., “Management of Inferior Vena Cava Tumor Thrombus in Locally Advanced Renal Cell Carcinoma,” Therapeutic Advances in Urology 7, no. 4 (2015): 216–229. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. Shuch B., Larochelle J. C., Onyia T., et al., “Intraoperative Thrombus Embolization During Nephrectomy and Tumor Thrombectomy: Critical Analysis of the University of California‐Los Angeles Experience,” Journal of Urology 181, no. 2 (2009): 492–498. [DOI] [PubMed] [Google Scholar]
- 3. Ciancio G., Manoharan M., Katkoori D., de Los Santos R., and Soloway M. S., “Long‐Term Survival in Patients Undergoing Radical Nephrectomy and Inferior Vena Cava Thrombectomy: Single‐Center Experience,” European Urology 57, no. 4 (2010): 667–672. [DOI] [PubMed] [Google Scholar]
- 4. Tongaonkar H. B., Kulkarni J. N., Kamat M. R., Dalal A. V., and Dandekar N. P., “Renal Cell Carcinoma Extending to the Renal Vein and Inferior Vena Cava: Results of Surgical Treatment and Prognostic Factors,” Journal of Surgical Oncology 59, no. 2 (1995): 94–100. [DOI] [PubMed] [Google Scholar]
- 5. Kayalar N., Oz B., and Bakir I., “Concomitant Surgery for Renal Neoplasm With Pulmonary Artery Tumor Embolism,” Journal of Thoracic and Cardiovascular Surgery 139, no. 4 (2010): e92–e93. [DOI] [PubMed] [Google Scholar]
- 6. Roberts S. A., Satija D., Gold H., et al., “Intraoperative Embolization During Inferior Vena Cava Tumor Thrombectomy for Renal Cell Carcinoma,” Journal of Kidney Cancer VHL 10, no. 4 (2023): 43–49. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7. Ciancio G., Shirodkar S. P., and Soloway M. S., “Renal Carcinoma With Supradiaphragmatic Tumor Thrombus: Avoiding Sternotomy and Cardiopulmonary Bypass,” Annals of Thoracic Surgery 89, no. 2 (2010): 505–511. [DOI] [PubMed] [Google Scholar]
- 8. Suggs W. D., R. B. Smith, 3rd , and DeKernion J. B., “Renal Cell Carcinoma With Inferior Vena Caval Involvement,” Journal of Vascular Surgery 14, no. 3 (1991): 413–418. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Video S1: Intraoperative transesophageal echocardiography showing tumor thrombus in the right atrium (Figure 3A,B).
Video S2: Intraoperative transesophageal echocardiography showing tumor thrombus occluding the right pulmonary artery (Figure 3C).
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.