Intravascular Extension Research Articles

Surgical management and outcomes of renal tumors with inferior vena cava extension among children: a single center retrospective study from Pakistan

ObjectiveThe aim of this study was to assess management and determine outcomes of renal tumors with inferior vena cava (IVC) and intracardiac (IC) extension in a tertiary care center in Pakistan.MethodsA retrospective chart review was conducted at the Aga Khan University Hospital, Karachi, Pakistan. All patients from 1 to 18 years of age with renal tumors with intravascular extensions, surgically managed from January 1988 till June 2016, were included. Data was extracted by reviewing medical records, and the tumor details, treatment and outcomes were analyzed.ResultsA total of 18 patients out of the total 61 patients with renal tumors, presented with IVC and/or IC extension, with the majority involving the right kidney. Mean age was 5.9 (SD:4.9) and a female preponderance (56%) was seen. Wilms tumor (77%) was the most common tumor type, with the level of tumor extension into IVC predominantly being below the diaphragm (55.5%). Fourteen patients received preoperative chemotherapy, with tumor regression, seen in 10. Most patients underwent thrombectomy through the renal vein (56%). Regarding outcomes, frequency of mortality and morbidity was 1 and 2, respectively, with 7 patients having no recurrent 5 years post-surgery.ConclusionA greater incidence (29.5%) of IVC and or IC Tumor extension was found compared to existing literature, which could likely be due to a higher referral rate to the center. Moreover, this is a single-center study and so a multi-center study is crucial to form an assessment of surgical management in resource-limited settings. Our study is the first from Pakistan on this particular renal tumor presentation. Considering the varying case presentations and surgical techniques used, further studies are needed to standardize surgical management and optimize patient outcomes.

Wilms Tumor with Vena Caval Intravascular Extension: A Surgical Perspective.

Wilms tumor (WT) is the most common kidney tumor in pediatric patients. Intravascular extension of WT above the level of the renal veins is a rare manifestation that complicates surgical management. Patients with intravascular extension are frequently asymptomatic at diagnosis, and tumor thrombus extension is usually diagnosed by imaging. Neoadjuvant chemotherapy is indicated for thrombus extension above the level of the hepatic veins and often leads to thrombus regression, obviating the need for cardiopulmonary bypass in cases of cardiac thrombus at diagnosis. In cases of tumor extension to the retrohepatic cava, neoadjuvant therapy is not strictly indicated, but it may facilitate the regression of tumor thrombi, making resection safer. Hepatic vascular isolation and cardiopulmonary bypass increase the risk of bleeding and other complications when utilized for tumor thrombectomy. Fortunately, WT patients with vena caval with or with intracardiac extension have similar overall and event-free survival when compared to patients with WT without intravascular extension when thrombectomy is successfully performed. Still, patients with metastatic disease at presentation or unfavorable histology suffer relatively poor outcomes. Dedicated pediatric surgical oncology and pediatric cardiothoracic surgery teams, in conjunction with multimodal therapy directed by a multidisciplinary team, are preferred for optimized outcomes in this patient population.

Simultaneous surgical management of renal cancer with atrial thrombotic extension and severe chronic coronary artery disease: a case report

BackgroundRenal cell carcinoma accounts for 2–3% of all malignant cancers in adults and is characterized by the potential development of venous tumor thrombus.Case presentationWe present a rare case of a 62-year-old Caucasian man who arrived in the emergency department for monosymptomatic hematuria. Further investigation revealed a right renal cell carcinoma with 16 cm intravascular extension through the renal vein into the inferior vena cava and right atrium associated with significant coronary artery disease based on the computed tomography scan and coronary angiography. To the best of our knowledge, after an extensive literature review, only one similar case has been reported with involvement of the contralateral kidney. Therefore, there are no applicable management recommendations. After performing coronary artery bypass graft surgery, we proceeded with an open right radical nephrectomy and inferior vena cava and right atrium thrombectomy under cardiopulmonary bypass and while the patient’s heart was still beating. The postoperative course went without complications, and the patient was discharged from the hospital on the 10th postoperative day.ConclusionsRadical nephrectomy and thrombectomy with reconstruction of the inferior vena cava combined with coronary artery bypass graft can be performed safely and effectively in selected patients with renal cell carcinoma and significant coronary artery disease. Multidisciplinary teamwork and careful patient selection are essential for optimal outcomes.

Anesthesia Approach for Nephrectomy in Full-Term Neonate with Suspected Wilms Tumor and Patent Foramen Ovale: A Case Report

Background: Nephrectomy for Wilms tumor presents a considerable challenge in pediatric anesthesia. This study aimed to describe the anesthesia approach for nephrectomy in a full-term neonate with suspected Wilms tumor and patent foramen ovale.
 Case presentation: A 25-day-old male neonate was referred with a longstanding intraabdominal mass present since birth. Echocardiography revealed a patent foramen ovale with a diameter of 2.7 mm and a left-to-right shunt. The patient also had a diagnosis of partial ileus obstruction, likely caused by the tumor's pressure on the left kidney. Preoperative fasting adhered to a "6-4-3-1" regimen. Normoglycemia was maintained throughout the perioperative period. The case was managed under general anesthesia without the use of the rapid sequence induction technique. Caudal analgesia was administered using 1.14 ml of 0.175% bupivacaine. Vigilant monitoring of blood loss, prevention of hypothermia, and effective pain management are vital aspects of the surgical procedure. For postoperative pain management, analgesia and morphine infusion were employed. The patient was then transferred to the neonatal intensive care unit (NICU) for observation for any signs of complications related to anesthesia and surgery.
 Conclusion: Nephrectomy in neonates is one of the challenges of pediatric anesthesia. Pre-anesthesia preparation in relation to hypertension control, analgesia plan and postoperative care site, transfusion strategy, and management of intravascular extension.

Anesthesia Approach for Nephrectomy in Full-Term Neonate with Suspected Wilms Tumor and Patent Foramen Ovale: A Case Report

Introduction: Nephrectomy for Wilms tumor presents a considerable challenge in pediatric anesthesia. This study aimed to describe the anesthesia approach for nephrectomy in a full-term neonate with suspected Wilms tumor and patent foramen ovale.
 Case presentation: A 25-day-old male neonate was referred with a longstanding intraabdominal mass present since birth. Echocardiography revealed a patent foramen ovale with a diameter of 2.7 mm and a left-to-right shunt. The patient also had a diagnosis of partial ileus obstruction, likely caused by the tumor's pressure on the left kidney. Preoperative fasting adhered to a "6-4-3-1" regimen. Normoglycemia was maintained throughout the perioperative period. The case was managed under general anesthesia without the use of the rapid sequence induction technique. Caudal analgesia was administered using 1.14 ml of 0.175% bupivacaine. Vigilant monitoring of blood loss, prevention of hypothermia, and effective pain management are vital aspects of the surgical procedure. For postoperative pain management, analgesia and morphine infusion were employed. The patient was then transferred to the neonatal intensive care unit (NICU) for observation for any signs of complications related to anesthesia and surgery.
 Conclusion: Nephrectomy in neonates is one of the challenges of pediatric anesthesia. Pre-anesthesia preparation in relation to hypertension control, analgesia plan and postoperative care site, transfusion strategy, and management of intravascular extension.

Management and Outcomes of Wilms Tumor With Suprarenal Intravascular Extension: A Pediatric Surgical Oncology Research Collaborative Study.

The purpose of this study was to describe management and outcomes from a contemporary cohort of children with Wilms tumor complicated by inferior vena caval thrombus. The largest series of these patients was published almost 2 decades ago. Since then, neoadjuvant chemotherapy has been commonly used to manage these patients, and outcomes have not been reported. Retrospective review of 19 North American centers between 2009 and 2019. Patient and disease characteristics, management, and outcomes were investigated and analyzed. Of 124 patients, 81% had favorable histology (FH), and 52% were stage IV. IVC thrombus level was infrahepatic in 53 (43%), intrahepatic in 32 (26%), suprahepatic in 14 (11%), and cardiac in 24 (19%). Neoadjuvant chemotherapy using a 3-drug regimen was administered in 82% and postresection radiation in 90%. Thrombus level regression was 45% overall, with suprahepatic level showing the best response (62%). Cardiopulmonary bypass (CPB) was potentially avoided in 67%. The perioperative complication rate was significantly lower after neoadjuvant chemotherapy [(25%) vs upfront surgery (55%); P =0.005]. CPB was not associated with higher complications [CPB (50%) vs no CPB (27%); P =0.08]. Two-year event-free survival was 93% and overall survival was 96%, higher in FH cases (FH 98% vs unfavorable histology/anaplastic 82%; P =0.73). Neither incomplete resection nor viable thrombus cells affected event-free survival or overall survival. Multimodal therapy resulted in excellent outcomes, even with advanced-stage disease and cardiac extension. Neoadjuvant chemotherapy decreased the need for CPB to facilitate resection. Complete thrombectomy may not always be necessary.

Nephron sparing surgery and surgical management of intravascular extension of Wilms tumor.

Although general treatment approaches for Wilms tumor differ between Children's Oncology Group and Société Internationale d'Oncologie Pédiatrique-Renal Tumors Study Group protocols, complex tumors that may be candidates for nephron sparing surgery (NSS) and those with intravascular tumor extension represent a management challenge. In both of these scenarios, anatomic considerations are important in guiding management, making these areas of significant similarities in management between the international groups. This paper aims to explore the current approaches to NSS and intravascular tumor extension by both international groups, with attention to the evidence supporting these approaches and current knowledge gaps.

Emergent Total Endovascular Arch Repair for Contained Aortic Arch Rupture: Another Tool in the Box.

To date, emergent total endovascular aortic arch repair has not been described in the literature. We present a 67-year-old female with a poorly differentiated posterior mediastinal sarcoma. Imaging obtained was concerning for intravascular extension of the tumor into the thoracic aorta. While awaiting radiation therapy, the patient complained of worsening chest and arm pain, vital signs demonstrating tachypnea and hypoxia. Subsequent imaging revealed an increase in vascular erosion, concerning for a contained rupture, with complete obliteration of the left mainstem bronchus. The patient was emergently taken for percutaneous endovascular repair of her aortic arch. A three-vessel physician modified fenestrated graft was created and deployed with concurrent stenting of the innominate, left carotid, and left subclavian arteries. Interval computed tomography angiography revealed patency in all stented vessels, with no endoleak and no evidence of pseudoaneurysm. The patient was able to undergo chemotherapy with favorable decrease in tumor burden. Total endovascular aortic arch repair, when planned carefully, is an attractive option in high-risk patients who are otherwise not ideally suited for open total arch replacement.

Thymoma: a rare cause for an intracardiac tumour.

A 56-year-old man presented with superior vena cava syndrome after recovery from severe COVID-19. Chest X-rays showed multiple bilateral pulmonary nodules (Panel A). A transthoracic echocardiogram revealed a mass in the right atrium of 54 × 31 mm, that protruded through the tricuspid valve and generated an obstructive gradient of 15 mmHg (Panel B; Supplementary Video 1). Contrast-enhanced chest computed tomography (CT) showed multiple pulmonary nodules (Panel C), and an intravascular extension of the intracardiac mass, deep into the innominate veins (Panels D and E). Volume 3D rendering CT showed extensive collateral venous circulation (Panel F). Steady-state free precession cine magnetic resonance imaging sequence showed an isointense mass with hyperintense areas in the right atrium, that measured 6.8 × 6.3 × 3.8 cm and prolapsed through the tricuspid valve (Panel G; Supplementary Video 2). The intracardiac mass was T1- and T2-weighted hyperintense (Panels H and I). Additionally, a mediastinum mass of 25 × 26 mm was found, with similar characteristics than the intracardiac mass.

Atrial invasion from primary lung adenocarcinoma extension via the pulmonary vein.

Intravascular extension of lung adenocarcinoma is one of the four defined routes of metastasis to the heart but is rarely described in the literature. This is a rare case of primary lung adenocarcinoma with intravenous extension to the left atrium via the pulmonary vein. A 56-year-old female presented to the hospital with chest tightness and dyspnea. Chest computed tomography revealed a right hilar mass extending through the right superior pulmonary vein into the left atrium. Transthoracic echocardiography revealed a large, partially mobile left atrial mass occupying the entire atrial cavity and affecting mitral valve closure. Endobronchial ultrasound with transbronchial biopsy of the right middle lobe of the lung histologically showed a poorly differentiated adenocarcinoma compatible with the primary lung cancer. The patient was deemed a poor surgical candidate by cardiothoracic surgery due to the extent of metastasis and was started on chemoradiation. The patient's left atrial tumor mass started shrinking in size after starting the treatment. This unique case displaying intravascular extension of lung cancer to the left atrium has rarely been described in the literature.

Nephroblastoma cavoatrial tumor thrombus-A challenge to anesthesiologist.

Nephroblastoma cavoatrial tumor thrombus-A challenge to anesthesiologist.

Unusual Case of Uterine Intravascular Leiomyomatosis with Lymphatic Spread to Pelvic Lymph Nodes

Abstract Introduction/Objective Intravascular leiomyomatosis, also known as intravenous leiomyomatosis, is characterized by presence of smooth muscle within venous spaces in the myometrium, usually in conjunction with a leiomyoma. Although presence of tumor within lymphatics in addition to veins are alluded to in literature, exclusively lymphatic spread with lymph node metastases have not been previously reported. Methods/Case Report A 50-year-old woman presented with left flank pain. CT pelvis showed an enlarged uterus with multiple large leiomyomata as well as pelvic lymph node enlargement. Hysterectomy with bilateral salpingo- ophorectomy and pelvic lymph node dissection was performed. Gross examination revealed multifibroid uterus. Separately sent pelvic lymph nodes showed well-circumscribed, whorled lesions resembling leiomyoma. Microscopically, in addition to typical leiomyomata, a 11.5 cm intramural tumor with epithelioid cells, very rare mitoses and no necrosis was identified. Adjacent to this mass, several large endothelial lined spaces (positive for D240 and negative for CD31), consistent with lymphatics, showed intravascular extension of the same epithelioid tumor. All the pelvic lymph nodes were replaced by the tumor. Due to the unusual morphology and pattern of spread, immunohistochemical stains were performed to rule out an endometrial stromal sarcoma and lymphangioleiomyomatosis. The lesion was positive for desmin, caldesmon, and negative for CD10 and HMB45. Ki67 was extremely low (<1%). Based on morphology and immunophenotype, the tumor was consistent with an epithelioid leiomyoma with highly unusual lymphatic spread through myometrial vessels to regional lymph nodes. Results (if a Case Study enter NA) NA Conclusion Intravascular leiomyomatosis is a rare condition with no reported progression to malignancy. Typically, benign smooth muscle is present in veins within the myometrium of a leiomyomatous uterus with progressive spread to the right heart via the inferior vena cava. We present the first report of a rare case of intravascular leiomyomatosis with spread exclusively via lymphatics to pelvic lymph nodes.

Commentary on surgical management, staging, and outcomes of Wilms tumours with intravascular extension: Results of the IMPORT study

This is a commentary on the manuscript entitled "Surgical Management, Staging, and Outcomes of Wilms Tumours with Intravascular Extension: Results of the Import Study".

Surgical management, staging, and outcomes of Wilms tumours with intravascular extension: Results of the IMPORT study

PurposeTo review surgical management, tumour stage and clinical outcomes in children with intravascular extension of Wilms tumour (WT) registered in a national clinical study (2012–19). MethodsWTs with presence/suspicion of tumour thrombus in the renal vein (RV) or beyond on radiology, surgery or pathology case report forms were identified. Only cases where thrombus was confirmed by surgeon and/or reference pathologist were included. Surgical management, disease stage, overall (OS) and event free survival (EFS) were investigated. Results69/583 (11.8%) patients met the inclusion criteria. Forty-six (67%) had abdominal stage III due to thrombus-related reasons: 11 had macroscopically incomplete resection, including 8 cases where cavotomy was not performed; 20 had piecemeal complete resection of thrombus; 15 had microscopically positive resection margins at the RV. 66% of tumour thrombi contained viable tumour. There were eight relapses and five deaths. EFS, but not OS, was significantly associated with completeness of surgical resection (P<0.05). OS and EFS were also significantly associated with histological risk group (P<0.05) but not with viability of tumour thrombus (P=0.19; P=0.59). ConclusionsWTs with intravascular extension have a high risk of local stage III due to thrombus-related reasons. Controlled complete removal of the thrombus should be the aim of surgery. Level of EvidenceLevel II

Role of anticoagulation in the management of tumor thrombus: A 10-year single-center experience.

Children with cancer diagnosis are overall at a higher risk of thrombosis. For a newly diagnosed blood clot, patients are commonly started on anticoagulants to prevent further extension and embolization of the clot. In the rare instance that a pediatric patient has a tumor thrombus, role of anticoagulation is less clear. Patients under 21years of age with a finding of tumor thrombus on imaging from 2010 to 2020 at Texas Children's Hospital were identified and their medical records were reviewed. A total of 50 patients were identified. Most thrombi were incidental findings at diagnosis; however, two patients presented with pulmonary embolism (PE). Inferior vena cava extension was noted in 36% of the patients, and 24% patients had an intracardiac tumor thrombus. Anticoagulation was initiated in 10 patients (20%). There was no difference in the rate of bland thrombus formation and/or embolization in patients who did or did not receive anticoagulation. However, three of the six patients with asymptomatic tumor thrombus who were started on anticoagulation had bleeding complications compared to only two patients in the no anticoagulation cohort (p<.05). Children with intravascular extension of solid tumors were not commonly started on anticoagulation at the time of diagnosis, irrespective of the extent of tumor thrombus. Furthermore, we observed a significant trend toward higher incidence of bleeding complications after initiation of anticoagulation for asymptomatic tumor thrombus. There is inadequate evidence at this time to support routine initiation of anticoagulation in pediatric patients with intravascular extension of solid tumors.

“The Way to a Man’s Heart” - Adrenocortical Carcinoma With Vascular Invasion Into the Right Atrium and Ventricle

Abstract Background: Adrenocortical carcinoma (ACC) is a rare aggressive malignant neoplasm which may present with intravascular extension into the inferior vena cava (IVC) and rarely into the right atrium (RA). Clinical Case: 62-year-old male with no prior known significant medical history presented to ED with 2-day history of mild hematuria with 3-week history of headache. Vital signs were normal other than blood pressure of 198/88 while physical exam was unremarkable. Headache subsided and blood pressure improved to 130/60 range after IV labetalol administration. CT abdomen and pelvis with contrast revealed a large right suprarenal mass extending into the right hepatic vein, IVC, and RA. The right adrenal gland was not visualized while the left adrenal gland and bilateral kidneys were normal. MRI chest, heart and abdomen with contrast showed heterogeneously enhancing lobulated right adrenal mass measuring 11.4 x 11 x 14 cm (AP, transverse, CC, respectively) with extensive tumor thrombus invading the right hepatic vein, IVC, RA and notably protruding into the right ventricle (RV) through the tricuspid valve during diastole. Technitium-99m MDP whole body scan did not show any uptake suspicious for metastases. Pre-op lab assessment showed mildly abnormal 1 mg dexamethasone suppression test but no evidence of ACTH suppression, elevated catecholamines or excess adrenal steroidogenesis. He underwent combined cardiothoracic and abdominal surgery on cardiopulmonary bypass with resection of adrenal mass, removal of thrombus from IVC, RA, RV and patch angioplasty of IVC with bovine pericardium. Pathology report was consistent with ACC (AJCC stage III). On 1 month postoperative follow-up, patient is clinically doing well with plans to start mitotane with addition of etoposide/doxorubicin/cisplatin (EDP) chemotherapy. Conclusion: ACC is a rare, highly aggressive malignancy which may produce extensive intravascular invasion. It may rarely extend to the RA and even rarer into the RV; with 42 and 1 reported cases, respectively. No study has conclusively found that vascular extension of ACC is a poor prognostic factor, hence surgical management is the primary strategy including cases with RA/RV involvement. There is lack of data and consensus regarding adjuvant or palliative medical therapy. However, in phase II trials combination of EDP chemotherapy and mitotane have shown response rates ranging from 11% to 54%. Reference: Alghulayqah, Abdulaziz, et al. “Long-term recurrence-free survival of adrenocortical cancer extending into the inferior vena cava and right atrium: Case report and literature review.” Medicine 96.18 (2017).

Follicular Variant of Papillary Carcinoma Thyroid with Massive Angioinvasion of the Internal Jugular Vein: Our Approach

Follicular variant of papillary carcinoma thyroid is an aggressive variant of papillary carcinoma thyroid. It is more commonly associated with extrathyroidal extension and regional lymphadenopathy. It can rarely be associated with microscopic vascular invasion but tumor thrombus into great veins is a rare phenomenon. We present a case of 60-year-old male with follicular variant of papillary carcinoma thyroid with tumor thrombosis in superior thyroid vein and internal jugular vein (IJV). We report a case of a 60-year-old male who presented with a large swelling in the lower part of left side of neck for 4 months. Clinical examination revealed a hard swelling of 12x8 cm in left side of neck. Ultrasonography showed a solitary thyroid mass of the left lobe and a dilated left superior thyroid vein and ipsilateral IJV. Fine-needle aspiration cytology revealed follicular variant of PTC cells. Total thyroidectomy was done. A tumor thrombus was discovered in the superior thyroid vein and left IJV was found to be dilated. The left IJV with superior thyroid vein was ligated and excised. The patient recovered well after the operation with no local or distant metastasis detected. Follicular variant of PTC commonly spreads to the lymph nodes. Vascular spread via direct intravascular extension through superior thyroid vein is extremely rare. On palpation cord like IJV is felt on the involved side. Neck ultrasound play important role in the diagnosis. Aggressive surgical treatment with IJV ligation above and below the tumor thrombus is recommended to minimize the risk of potentially fatal complications of the intraluminal masses. Intravascular tumor extension into IJV of neck in follicular variant of PTC is rare and can be associated with serious consequences. Total thyroidectomy with thrombectomy with ligation of IJV must be done.

Tumor Thrombus- a Single Center Experience with Tumor Thrombus and Role of Anticoagulation

Background: Children with cancer diagnosis are overall at a higher risk of thrombosis. For a newly diagnosed blood clot or bland thrombus (fibrin clot without neoplastic cells), patients are commonly started on anticoagulants such as unfractionated heparin (UFH) or low molecular weight heparin (LMWH) to prevent further extension and embolization of the clot. In the rare instance that a pediatric patient has a tumor thrombus, defined as the extension of the tumor into a vessel, the role of anticoagulation is less clear. Objective: The aim of this study was to review the data of patients at Texas Children's Hospital (TCH) in the past ten years with a diagnosis of tumor thrombus, the management strategy and role of anticoagulation- its indication, response and complications noted. Methods: Patients under 21 years of age with a finding of tumor thrombus on imaging from 2010-2020 at TCH were identified and their medical records were reviewed. Demographics, location of tumor thrombus, imaging, treatment approach, use of anticoagulation, response to standard treatment (chemotherapy/surgery) and anticoagulation, and outcomes were assessed. This retrospective chart review was approved by the Institutional review board at Baylor College of Medicine. Results: We identified a total of 50 patients with a finding of tumor thrombus in the past ten years treated at our center. Most of them were incidental findings at diagnosis, however there were two patients who initially presented with pulmonary embolism (PE) and later on pathological exam of thrombectomy tissue were found to have relapse of their primary malignancy and tumor thrombus to be the etiology of the PE. Tumor thrombus was mostly identified in the systemic vessels draining the primary tumor. IVC extension was found in 36% of the patients and 24% had an intracardiac tumor thrombus (Table 1). Hepatoblastoma (26%) was most commonly associated with tumor thrombus, followed by Wilms tumor (12%) (Figure 1). Anticoagulation was initiated in 10 patients (20%) with or without standard chemotherapy (rationale for anticoagulation mentioned in Table 2), while remaining patients received the standard treatment for the primary tumor, including chemotherapy, surgery, and/or radiation. In 32.5% of the patients who did not receive anticoagulation, there was a documented decrease in size of tumor thrombus with chemotherapy. Among patients who received anticoagulation, only 2 of the 10 patients showed response to anticoagulation in terms of improvement of symptoms (Improved leg swelling in patient F, improved kidney function with resolution of Renal vein thrombus in patient H). The three patients with pulmonary embolism did not show any resolution of symptoms with initiation of anticoagulation. However, 40% (4/10) patients were noted to have bleeding complications from anticoagulation requiring brief interruption or complete stoppage of anticoagulation (Table 2). On statistical analysis, this association was found to be statistically significant with higher proportion of bleeding events occurring in patients who received anticoagulation (p= 0.01). Conclusion: Children with intravascular extension of solid tumors were not commonly started on anticoagulation at the time of diagnosis despite evidence of extensive tumor thrombus. Furthermore, we observed a significant trend toward higher incidence of bleeding complications after initiation of anticoagulation. We conclude that there is not enough evidence to support routine initiation of anticoagulation in pediatric patients with intravascular extension of solid tumors. Further studies are needed to identify high-risk groups for whom the benefits of anticoagulation may outweigh its risks. We would also emphasize that it is essential to consider a possibility of relapsed disease if patient with a history of malignancy presents with symptoms of thromboembolism and is not responding to anticoagulation as would normally expect. Disclosures No relevant conflicts of interest to declare.

Intravascular extension of Wilms tumor: Characteristics of tumor thrombus and their impact on outcomes

Studies describing intravascular involvement in Wilms tumor have focused on illustrating individual institutional experience and the elements of surgical management. Thrombus characteristics like extent, patterns of regression, and correlation with the surgical findings, intraluminal adhesion, and viable tumor in the thrombus, and patency of the inferior vena cava (IVC) have not been systematically described. The aim of this study is to evaluate these thrombus characteristics and explore their impact on the overall outcomes. All patients with histologically confirmed Wilms tumors with intravascular thrombus diagnosed in the pediatric oncology unit of Tata Memorial Hospital registered from 2006 to 2019 were included. Data regarding clinical, radiological, and surgical particulars were retrieved from the prospectively maintained institutional database. Specific data for the thrombus included: distal extent before and after neoadjuvant chemotherapy, correlation of extent with the surgical findings, completeness of thrombectomy, the presence of a viable tumor in the thrombus, and the patency of the IVC. Survival analysis was performed utilizing the Kaplan-Meier method on SPSS software version 25. The study included 43 (9.9%) of the 432 patients with Wilms tumor having intravascular extension. Retrohepatic IVC (33.3%) followed by atrioventricular (26%) formed the frequent levels of thrombus with maximum regression occurring after chemotherapy in the latter (Summary figure). The overall concordance rate between computed tomography (CT) scan and surgical findings for the presence of thrombus was 86% and 4 patients had the thrombus limited to a lower level than the preoperative scan. At a median follow-up of 5-years, the 5-year event-free and overall survival was 81% and 82.2% respectively. Atrioventricular thrombus (p=0.003) and postoperative patency of IVC (p=0.02) were significantly associated with inferior survival, while the extent of regression, thrombus fracture, and viability was not significant. The findings of this study bring forth the characteristics of intravascular tumor thrombus affecting the outcomes which can be validated in future prospective studies. Although the ideal method for radiological assessment of the intravascular thrombus is elusive, CT scan provided adequate information for the presence and level of the intravascular thrombus with reasonable accuracy in this study. Study limitations include small sample size, the limited number of events, and lack of multivariate analysis to rule out confounding factors that could influence the observed findings. Atrioventricular thrombus and occlusion of IVC represent adverse prognostic factors. The extent of regression, fracture, and viability of thrombus did not affect survival in this study.

Adapted Cavotomy Technique for Pheochromocytoma Associated Tumor Thrombi in a Dog

Background: In dogs pheochromocytoma usually compress and invade into the adjacent vessels and structures, which may lead to the occurrence of caudal vena caval tumor thrombi. The surgical approach in these cases requires adrenalectomy with caval thrombectomy. Conventionally, tourniquets and partial occlusion clamp are used to reduce intraoperative blood loss, but in dogs with a large thrombus associated to a great local tumor invasion, the traditional technique may be hindered. The aim of this study was to report the use of a purse-string suture during venotomy of the caudal vena cava for thrombectomy, as an alternative to tourniquet and partial occlusion clamp.Case: An 11-year-old male Daschound breed dog, was referred for evaluation because of the appearance of small blackened nodules in the ventral abdomen. During a search for metastatic lesions with abdominal ultrasound, the right adrenal was identified with significant volume increase, and presence of tumor-associate circular formation that appeared to invade the caudal vena cava, suggestive of neoplastic invasion or thrombus. Abdominal computed tomography showed caudal vena cava in its hepatic portion presenting considerable increase in diameter, with caudal dilation and presence of hypoattenuating material in its lumen. Right adrenal gland with rounded appearance and regular borders, heterogeneous parenchyma and juxtaposed caudal vena cava suggesting invasion of this, confirming the sonographic findings. During exploratory celiotomy, adherence of the adrenal mass to the right renal vessels and invasion of the caudal vena cava were observed, leading to the need of nephrectomy and venotomy for thrombectomy. To perform the venotomy, a Rumel tourniquet was placed loosely around the vena cava only caudal to the invasion point of the tumor thrombus, cranially, tourniquet application was not possible due to the presence of a large thrombus extending into the intrahepatic cava. Therefore, a purse-string suture was applied around the invasion point of the vena cava tumor thrombi. Thus, during the thrombectomy, while dissecting with the scalpel blade, the purse-string suture was gently tightened, minimizing hemorrhage and allowing the venotomy to close immediately after thrombi removal. Histopathological mass analysis allowed the diagnosis of malignant pheochromocytoma with intravascular extension of the tumor, and the patient remained without clinical changes for 18 months.Discussion: When caval invasion by the adrenal mass is present, the application of Rumel tourniquets around the vena cava cranial and caudal to the tumor thrombus invasion point is recommended to reduce intraoperative hemorrhage during thrombectomy. However, due to the presence of a large thrombus extending into the intrahepatic cava in the presente report, it was not possible to apply the cranial tourniquet, just the caudal one. Thus, the technique adapted using a purse-string suture during venotomy of the caudal vena cava for thrombectomy was extremely efficient in controlling hemorrhage, while allowing rapid venotomy closure without the need for partial occlusion vascular clamp, reducing the surgical time. A tumor thrombus in the vena cava associated with adrenal gland tumors are amenable to adrenalectomy and thrombectomy without significantly increasing perioperative morbidity and mortality rates, assuming the surgeon is experienced in appropriate techniques. Moreover, the presence of tumor invasion does not seem to be predictive of the outcome of the cases, in agreement with what happened in this case.