Arterial Tumor Embolism Research Articles

Pulmonary lymphangitic carcinomatosis-An experience at autopsy.

Pulmonary lymphangitic carcinomatosis is an uncommon mode of metastases, characterized by diffuse infiltration of the lymphatics malignant cells, and is mainly the subject of case reports or a few case series. The aim of this study is to study the clinicopathological features of this entity at autopsy. This is a retrospective study of data collected over an 11-year period at a tertiary-care hospital. Clinicopathological data of all autopsies with lymphangitic carcinomatosis were analyzed with reference to their demographics, clinical presentation, investigations, sites of primary cancer, and other relevant findings at autopsy. Among 255 cases of malignancies encountered in 7521 autopsies during the study period, 43 patients (16.9%) showed pulmonary metastasis with 22 (13 females and 9 males, mean age of 52.04 years) histologically proven lymphangitic carcinomatosis of the lungs. An antemortem diagnosis was made in only 1 of the 22 cases. The most common sites of carcinoma had been the stomach or the lungs (40.9%) and dyspnea had been the main symptom. The lungs, in addition, showed metastatic deposits and arterial thrombi and/or tumor emboli. The most common nonpulmonary site for metastasis was the liver and lymph nodes. Pulmonary lymphangitic carcinomatosis is often an underdiagnosed clinical entity and the presence of acute progressive respiratory failure in patients with epithelial cancers should raise clinical suspicion. This is one of the largest series to be reported at autopsy.

Minimizing blood loss with direct percutaneous polymethylmethacrylate embolization before corpectomy for vascular spinal tumors.

Standard surgical treatment for vascular spinal tumors, including renal cell carcinomas and hemangiomas, may result in significant blood loss despite preoperative arterial tumor embolization. This is a retrospective review of 12 patients who underwent direct percutaneous polymethylmethacrylate embolization (DPPE) with or without feeding artery embolization before partial or complete corpectomy for the resection of vascular spinal tumors (2013-2018). Estimated blood loss (EBL) was compared to the blood loss reported in the literature and to patients receiving standard arterial embolization before surgery. The mean EBL for 12 patients was 1030 mL; three of 12 patients required blood transfusions. For the single level corpectomies, the EBL ranged from 100 mL to 3900 mL (mean 640 mL). This mean blood loss was not increased in patients receiving only DPPE preoperatively versus those patients receiving preoperative arterial embolization in addition to DPPE (1005 vs. 1416 mL); in fact, the EBL was significantly reduced for those undergoing DPPE alone. In this initial study, nine patients treated with DPPE embolization alone before spinal tumor resection demonstrated reduction of intraoperative blood loss compared to three patients having arterial embolization with DDPE.

Primary mesenchymal chondrosarcoma of the kidney without HEY1-NCOA2 and IRF2BP2-CDX1 fusion: A case report and review.

Mesenchymal chondrosarcoma (MC) of the kidney is rare. To the best of our knowledge, the current report is the first case of a giant extraskeletal MC that arose primarily from the right kidney and mimicked renal cell carcinoma at the locally advanced stage (cT3bN0) with vena cava thrombus and multiple pulmonary arterial tumor emboli. Additionally, the literature on renal EMC is reviewed and the possibilities of oncogenic heterogeneity are discussed. A 64-year-old woman was admitted to Yamagata University Hospital for sudden onset of asymptomatic gross hematuria. CT revealed a 90 mm renal mass without calcification in the right kidney and tumor thrombus extending to the inferior vena cava. Radical nephrectomy with thrombectomy was performed. Lung metastasis was detected 2 months later. The patient received systemic chemotherapy, which was only marginally effective. She died of the malignancy 8 months after surgery. Microscopic examination of the tumor revealed typical histology of MC and a lack of HEY1-NCOA2 and IRF2BP2-CDX1 gene fusions in the tumor tissues. Not all MC patients may exhibit chromosomal alterations in the tumor, suggesting the presence of genetically heterogeneous pathways of MC oncogenesis. Further studies are required to confirm the present findings and reinforce the molecular diagnosis of MC.

RAPIDLY PROGRESSIVE PULMONARY HYPERTENSION AND RESPIRATORY FAILURE FROM UNEXPECTED TUMOR THROMBOTIC MICROANGIOPATHY IN A YOUNG WOMAN

SESSION TITLE: Monday Fellow Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/21/2019 02:30 PM - 03:15 PM INTRODUCTION: Pulmonary tumor thrombotic microangiopathy is an uncommon disorder in which tumor cells embolize to the pulmonary vasculature, causing activation of coagulation and fibrocellular subintimal proliferation. Vascular stenosis causes pulmonary hypertension (PH), right heart failure, and death. We present a case of PH and respiratory failure in a young woman with tumor emboli from high risk type human papillomavirus (HPV)-associated cervical cancer. CASE PRESENTATION: A 30 year old woman with asthma but in good health presented with dyspnea and was diagnosed with pneumonia. When antibiotics did not help, lower extremity ultrasound identified deep venous thrombi. Despite anticoagulation with Apixaban, dyspnea worsened, and she was hospitalized for suspected CTEPH. Initial vitals were BP 103/61 mmHg, HR 117/min, RR 28/min, T 36.4C, and SaO2 95% (15 LPM O2). Lungs were clear, heart rhythm was regular with increased P2, and edema was absent. Labs included AST 64 U/L and BNP 450 pg/mL. Hypercoagulable testing, rheumatologic studies, pregnancy testing, and infectious work-up were negative. ECHO showed a severely dilated RV, reduced function, and RVSP 40-50 mmHg. RHC showed RAP 14 mm Hg, PAP 59/33 (mean 43) mmHg, PCWP 7 mmHg, PA saturation 38%. CT angiography showed bilateral ground-glass opacities and consolidation with a dilated pulmonary trunk but no significant lymphadenopathy or pulmonary embolism. Despite vasodilators, PH and heart failure worsened, and veno-arterial ECMO was initiated. CT abdomen, part of the transplant evaluation, showed pelvic adenopathy and an abnormal cervix. A 2-cm cervical mass was palpated, but biopsy showed benign squamous mucosa. A subsequent true-cut cervical biopsy showed moderately to poorly differentiated squamous cell carcinoma with lymphovascular invasion. Surgical lung biopsy, performed to help define the lung disease, showed metastatic squamous cell carcinoma with arterial and lymphatic tumor emboli resulting in pulmonary infarction. Chemotherapy (Taxol/Cisplatin) was given, but she did not improve. She opted for palliative care and died from malignancy-related complications. Of note, cervical cells were positive for type 18-HPV DNA. DISCUSSION: This case highlights several important considerations. A thorough PH clinical assessment is warranted when symptoms progress despite therapy. Among the etiologies of PH, malignancy should also be considered, regardless of age or the absence of apparent risk factors. Finally, it is noteworthy that vaccination might have prevented disease in this instance: available vaccines protect against several HPV types, and all protect against HPV types 16 and 18, which have the highest cervical cancer risk. CONCLUSIONS: Though uncommon, pulmonary tumor thrombotic microangiopathy should be considered in patients with respiratory failure and PH of unclear etiology, particularly when symptoms progress despite medical therapy. Reference #1: Price LC et al, Pulmonary tumour thrombotic microangiopathy. Curr Opin Pulm Med. 2016 Sep;22(5):421-8. Reference #2: Godbole R et al. Pulmonary Tumor Thrombotic Microangiopathy: Clinical, Radiologic, and Histologic Correlation. J Clin Imaging Sci. 2015 Jul 31;5:44. Reference #3: Martínez-Gómez X et al. Multidisciplinary, evidence-based consensus guidelines for human papillomavirus (HPV) vaccination in high-risk populations. Euro Surveill. 2019 Feb;24(7). DISCLOSURES: no disclosure on file for Charles Hoopes; No relevant relationships by Timothy Lewis, source=Web Response No relevant relationships by Tyler Reynolds, source=Web Response No relevant relationships by Victoria Rusanov, source=Web Response no disclosure on file for Jose Tallaj; no disclosure on file for Vincent Valentine; No relevant relationships by Raymond Wade, source=Web Response No relevant relationships by Keith Wille, source=Web Response

Acute lower limb ischemia and intestinal necrosis due to arterial tumor embolism from advanced lung cancer: a case report and literature review

BackgroundArterial tumor embolism (ATE) is a rare but life-threating complication.Presentation of caseA 55-year-old man with acute lower-limb ischemia was referred to our hospital after endovascular intervention failed and underwent above-the-knee amputation for severe limb necrosis. On postoperative day 8, he developed small bowel necrosis and underwent resection. Histopathological examination of the resected bowel revealed that the submucosal arterial emboli were positive for the markers of squamous cells. He had unresectable lung squamous cell carcinoma with left atrium invasion. The subsequent embolisms were thought to be caused by the advanced lung cancer.ConclusionATE is rare but should be considered as a differential diagnosis for unidentified arterial occlusion.

Laparoscopic partial nephrectomy following tumor embolization in a hybrid room. Feasibility and clinical outcomes

PurposeIn order to limit ischemia and operative bleeding during and after partial nephrectomy we developed a clampless laparoscopic technique, in a hybrid operating room, immediately after super-selective arterial embolization of the renal tumor. We evaluated feasibility and morbidity of this new approach of zero ischemia in partial nephrectomy. MethodsWe included prospectively 50 consecutive patients treated in a hybrid operating room by this new technique for a localized renal tumor in a university hospital between May 2015 and January 2017. We evaluated perioperative data, postoperative complications, surgical margin and modification of renal function one month after surgery. Renal tumor complexity was evaluated by the R.E.N.A.L. score. ResultsWe included 30 (60%) men and 20 (40%) women with a median age of 61 years (32–84) and a median BMI of 26.85 kg/m2 (20.1–46.4). Tumors were at low, median and high complexity in respectively 11 (22%), 32 (64%) and 7 (14%) cases. Median endovascular and surgical procedures durations were 43 min (16–120) and 80 min (32–150). Median blood loss was 100 mL (10–850). Two Clavien II complications occurred. Median length of hospital stay was 3 days (2–7). Renal function was not modified one month after partial nephrectomy. Median tumor size was 3 cm (1.2–8). Forty tumors (80%) were malignant and surgical margins were positive in one (2%). ConclusionsClampless laparoscopic partial nephrectomy in a hybrid operating room without pedicular dissection after previous tumoral embolization is a technically safe and carcinologically efficient mini-invasive alternative for the management of localized renal tumors.

Axillary artery tumor embolism secondary to mitral valve myxosarcoma in a dog

To describe the clinical presentation, treatment, and outcome of a dog with an arterial tumor embolism. An 11-year-old, neutered male Irish Setter presented with acute right forelimb lameness. The dog was unable to bear weight on the right forelimb, which was cool to the touch with no palpable pulses. Diagnosis of thromboembolism was confirmed using angiography, revealing a lack of blood flow to the right axillary artery. Balloon angioplasty, thrombosuction, and infusion of the thromboembolism with tissue plasminogen activator were used to achieve increased, but not complete, blood flow through the vasculature. Echocardiogram revealed vegetative mitral valve lesions consistent with endocarditis, thrombus, neoplasia, or a combination thereof. At the time of discharge, there was improvement in the temperature and motor function of the proximal limb but no conscious proprioception or deep pain sensation in the distal limb. Histopathologic analysis of the sample retrieved with thrombosuction was consistent with a diagnosis of myxosarcoma. A series of 3 rechecks showed continued improvement in neuromuscular function. Treatment for suspected mitral valve myxosarcoma was declined. The patient was lost to follow up until being presented for necropsy 16 months later. Necropsy confirmed myxosarcoma of the mitral valve with tumor emboli to the coronary arteries, lungs, and the right axillary artery. To the authors' knowledge, there is no report of myxosarcoma originating on the mitral valve in dogs, although it has been reported in the human literature. To the authors' knowledge, there are also no reports of tumor embolism of the axillary artery in a dog. This case demonstrates a unique presentation of a dog that had a myxosarcoma tumor embolism. It also describes the use of angiography for diagnosis and localization of the vascular obstruction and a variety of interventional techniques for the treatment of thromboembolism.

Timely diagnosis of pulmonary artery tumor embolism by ultrasound-guided transbronchial needle aspiration.

Pulmonary artery tumor embolism (PATE) is a rare disease without an established diagnostic method. In an autopsy series, however, the incidence of PATE was relatively high, between 3% and 26% in patients with a solid tumor. Here we report a case of a patient with a massive PATE from hepatocellular carcinoma diagnosed safely and promptly by endobronchial ultrasound-guided transbronchial needle aspiration.

Massive Postoperative Pulmonary Artery Tumor Embolism from Renal Cell Carcinoma

A 54-YR-OLD man with renal cell carcinoma underwent radi cal nephrectomy and inferior vena cava (IVC) thrombectomy. The tumor thrombus in the IVC had a length of 8.8 cm and extended 2.6 cm from the right atrium. Surgery was completed smoothly with suprahepatic IVC cross-clamping. Transesophageal echocardiographic examination was conducted, which did not reveal any embolism in the heart or pulmonary artery.On postoperative day 2, the patient complained of dyspnea, accompanied by hypoxemia and tachycardia. Enhanced computed tomography revealed defects in both pulmonary arteries. The arrow in the image indicates an embolus in the left pulmonary artery. An emergency operation was performed under cardiopulmonary bypass. The patient’s blood pressure remained normal before anesthesia induction; however, it decreased dramatically after induction, and the administration of inotropic or vasopressor agents was not very effective. Hypotension (systolic blood pressure, approximately 70 mmHg; mean blood pressure, approximately 50 mmHg) was not corrected until extracorporeal circulation was established. However, the hypoxemia was improved after tracheal intubation. The cancer thrombus and clots were removed from the pulmonary artery. Because of the probability that clots were formed in the IVC as the result of the residual thrombus, anticoagulation therapy—involving subcutaneous injection of low-molecular-weight heparin for 10 days, followed by oral administration of aspirin—was initiated following the operation for pulmonary embolism removal. The patient was discharged without further complications 2 weeks later.Radical nephrectomy with IVC thrombectomy is the most effective therapeutic option for renal cell carcinoma patients with tumor thrombus of the IVC.1 Thrombus embolization is rare, but is associated with an extremely high mortality rate.2 Use of transesophageal echocardiography for this operation helps in the diagnosis of thrombus migration.3 However, in the present case, transesophageal echocardiography did not detect residual thrombus in the IVC.The authors declare no competing interests.

Carcinoma embolization in coronary artery causing myocardial infarction: Diagnosis from coronary thromboaspirate

A unique case of myocardial infarction due to coronary artery tumor embolism from colonic adenocarcinoma is described. A 79-year-old man with a history of rectal carcinoma with lung metastases 15 years and 9 years before, respectively, was subjected to primary percutaneous coronary intervention for myocardial infarction with aspiration of a thrombus from the occluded artery. The retrieved material contained fragments of adenocarcinoma tissue. To the best of our knowledge, this is the first reported case of adenocarcinoma coronary embolism diagnosed during life from coronary artery aspirate.

Effect of hepatic artery embolization on liver hypertrophy response in a rabbit liver VX2 tumor model

Portal vein embolization not only induces hypertrophy of the non-embolized liver, but also enhances tumor growth. The latter could be prevented by embolizing the hepatic arteries supplying the tumor-bearing liver segments. This study aimed to determine the effects of transcatheter arterial embolization (TAE) on tumor volume and liver regeneration in a rabbit VX2 tumor model. Twenty-three rabbits underwent subcapsular tumor implantation with a VX2 tumor. Two weeks after implantation, 18 rabbits were used for TAE experiments, 5 were for sham controls. Tumor response and liver regeneration response of the embolized cranial and non-embolized caudal liver lobes were assessed by CT volumetry, liver to body weight index, and the amount of proliferating hepatocytes. All super-selective arterial tumor embolization procedures were performed successfully. Despite embolization, the tumor volume increased after an initial steady state. The tumor volume after embolization was smaller than that of the sham group, but this difference was not significant. Massive necrosis of the tumor, however, was seen after embolization, without damage of the surrounding liver parenchyma. There was a significant atrophy response of the tumor bearing cranial lobe after super-selective arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized, caudal lobe. This regeneration response was confirmed histologically by a significantly higher number of proliferating hepatocytes on the Ki-67 stained slides. Super-selective, bland arterial coil embolization causes massive necrosis of the tumor, despite increase of volume on CT scan. Atrophy of the tumor bearing liver lobe is seen after arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized lobe, despite absence of histological damage of the tumor-surrounding liver parenchyma.

Pulmonary Artery Tumor Embolism in a Patient With Previous Fibroblastic Osteosarcoma

A 48-year-old man was referred for left pulmonary metastasis and a left pulmonary artery embolus. The patient had T-cell acute lymphoblastic leukemia and fibroblastic osteosarcoma. A left pneumonectomy was performed successfully and the histologic report concluded that an embolic deposit of osteosarcoma was present. Pulmonary artery tumor embolism is a rare presentation in patients with previous fibroblastic osteosarcoma. It is important to suspect this diagnosis in a patient with cancer who presents with a pulmonary artery embolus.

Recurrent leiomyosarcoma presenting as malignant arterial tumor thrombus

► The report reviews unique arterial embolic phenomena in the context of newly diagnosed recurrent leiomyosarcoma. ► Metastatic work-up should be initiated in those diagnosed with malignant arterial tumor emboli.

Pulmonary Tumor Thrombotic Microangiopathy: A Clinical Analysis of 30 Autopsy Cases

Pulmonary tumor thrombotic microangiopathy (PTTM) is a unique, rare and fatal form of pulmonary arterial tumor embolism. The aim of this study was to evaluate the clinical characteristics and pathological and immunohistochemical findings of PTTM. Autopsy records dated between January 1983 and May 2008 in our hospital were reviewed, and those of patients who died from pulmonary tumor embolism resulting from malignant neoplasm were retrieved. The relevant tissue slides were reevaluated and examined immunohistochemically to confirm the diagnosis. Among 2,215 consecutive autopsy cases of carcinoma, 30 patients (1.4%) were diagnosed with definitive PTTM. The common symptom was progressive dyspnea. A hypercoagulative state was observed in all measured cases (n = 21). The chest computed tomography findings (n = 6) included consolidation, ground-glass opacity, small nodules and a tree-in-bud appearance. Perfusion scans were performed in seven patients, six of whom demonstrated multiple small defects. The median survival time after the initiation of oxygen supplementation was nine days. The most frequent primary site was the stomach (n = 18 ; 60%) , and the most frequent histological type was adenocarcinoma (28/30 ; 93.3%) . The immunohistochemical findings for tumor cells located within the tumor emboli were positive for vascular endothelial growth factor (28/29 ; 96.6%) and tissue factor (29/29 ; 100%). Clinicians should suspect PTTM in cancer patients who exhibit acute worsening respiratory insufficiency accompanied by a hypercoagulative state without embolism in major pulmonary arteries. The PTTM patients evaluated in our study had very poor prognoses. Vascular endothelial growth factor and tissue factor may play important roles in PTTM.

Phase III Studies of Bevacizumab (B) in Combination with Chemotherapy in Patients with HER2-Negative Metastatic Breast Cancer (MBC): Summary of Selected Adverse Events.

Abstract BackgroundA number of chemotherapy agents are used in the first-line treatment of patients with HER2-negative MBC. Three multicenter, randomized Phase III trials have demonstrated significant improvements in progression-free survival (PFS) when adding B to chemotherapy (C) in the first line treatment of women with MBC. These include E2100 (n=722), an open-label trial evaluating weekly paclitaxel (P) +/- B 15 mg/kg; AVADO (n=736), a placebo-controlled, double-blind trial evaluating docetaxel every 3 weeks +/- B 7.5mg/kg or B 15 mg/kg; RIBBON-1 (n=1237), a placebo-controlled, double-blind trial assessing capecitabine (C), Taxane (T) or Anthracycline (A) +/- B 15 mg/kg.Bevacizumab has a characteristic safety profile across a number of different tumor types when used as either a single agent or in combination with chemotherapy. Selected adverse events from breast cancer phase III trials will be summarized to show how different types of chemotherapy affect the adverse event (AE) rates in the first-line MBC setting.MethodsGrade 3–5 non-hematological events and Grade 4 or 5 hematological events using the NCI-CTC Version 2 (E2100) and the NCI CTCAE Version 3 (AVADO and RIBBON-1) are recorded and are summarized for B-related AEs by individual treatment arm from these three studies. These AEs included arterial tumor embolism (ATE), gastrointestinal perforation, hypertension, left ventricular systolic dysfunction, venous thromboembolism, proteinuria, bleeding, and wound-healing complications.ResultsAnalyzing the incidence of known B-related AEs in the placebo arms and B-containing arms of the E2100, AVADO, and RIBBON-1 studies, we found that hypertension ranged from 0 to 2% for patients in the placebo arms and from 2.8 to 16% for patients in the B-containing arms (E2100, 16.0%; the AVADO study, B 7.5 mg/kg cohort, 0%; the AVADO study B 15 mg/kg cohort, 2.8% for; the RIBBON-1 capecitabine cohort, 9.4%; the RIBBON-1 taxane cohort, 8.9%; and the RIBBON-1 anthracycline cohort, 10.0%). For all other B-related AEs the differences between the placebo arms and the B-containing arms were of smaller magnitude. Treatment discontinuation rates in the B-containing arms varied across trials, ranging from 11.9% to 27.9% compared with 4.0 to 19% for the placebo arms. By chemotherapy backbone, treatment discontinuation rates for patients receiving B were higher relative to the placebo arm for the taxane cohort (7.8% vs. 24.1%) and the anthracycline cohort (4.0% vs. 14.3%). There was no difference in treatment discontinuations for patients in the capecitabine cohort (11.9% for both arms).ConclusionsThe addition of B to chemotherapy is associated with an increased frequency of selected adverse events that have been observed across randomized MBC studies. Treatment discontinuation rates for adverse events vary across trials and may be a function of the chemotherapy agent, dose, and schedule. With the exception of hypertension, bevacizumab-related Grade 3–5 adverse events occurred in fewer than 5% of patients. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6083.

Preoperative Portal Venous and Hepatic Arterial Embolization of Tumor

Although the goal of embolization is usually to create therapeutic ischemia or hemostasis without surgery, the rationale for preoperative embolotherapy is different in several respects. First, the aim is to prepare patients for definitive surgical resection rather than cure or palliation, and, thus, the goals and expectations are limited and defined by close communication between the interventionalist and the surgeon. Second, when considering segmental resection, the normal liver should be protected from procedural damage. Third, the search for extrahepatic disease is crucial for these patients because resection is typically abandoned in favor of alternative therapies for patients with systemic disease. Finally, intraoperative ultrasound should always be considered to survey the future liver remnant for unsuspected small tumors and allow ablation of these lesions to maximize the success of partial hepatectomy. This article describes preoperative hepatic arterial and portal venous embolization in patients with or without cirrhosis complicated by tumors judged eligible for surgical resection or orthotopic liver transplantation (OLT). Each type of embolization will be reviewed in terms of indications and contraindications, technique, and complications. Finally, the outcomes will be evaluated in terms of morbidity, mortality, and tumor recurrence rates.

Acute Lower Extremity Ischemia Secondary to Salivary Gland Tumor Embolus

Malignant arterial tumor emboli of sufficient size that is capable of causing organ infarction or ischemia are exceedingly rare. The majority of these emboli are associated with either primary or secondary pulmonary malignancies and commonly occur perioperatively or immediately postoperatively. This study describes an unusual case of acute lower extremity ischemia secondary to a malignant parotid tumor embolus with evidence of left ventricular involvement.

Primary Malignant Hepatic Pheochromocytoma with Negative Adrenal Scintigraphy

A 60-year-old male patient with hypertension was referred to our hospital because of insufficient blood pressure control (190/98 mmHg) and to rule out secondary hypertension. A computed tomography scan revealed no adrenal tumor but a large liver mass (5 x 5 cm), and magnetic resonance imaging showed a high signal intensity lesion on the T2-weighted image. Twenty-four hour urinary excretion of catecholamine metabolites was markedly increased, although a 123I-metaiodobenzyl guanidine (MIBG) scintigram failed to show accumulation in the hepatic mass, and no difference was noted between the catecholamine concentration in the tumor-drainage vein and that obtained from the vein draining from the non-tumor area. Liver biopsy did show features compatible with pheochromocytoma (i.e., chromogranin A-positive cells). Transcatheter arterial embolization of the liver tumor was conducted and resulted in a marked (50%) decrease in the 24-h urine normetanephrine excretion. Several metastatic foci were noted in the spinal bone and transcatheter arterial embolization (TAE) was also conducted with successful results. Thus, we experienced a case of primary malignant hepatic pheochromocytoma with negative 123I-MIBG scanning.

Appendicular arterial tumor embolization in two cats with pulmonary carcinoma

A 13-year-old neutered male Persian cat and an 11-year-old neutered female Persian cat were examined because of an acute onset of lameness. In both cats, conscious proprioception and reflexes were diminished in the affected limb. In 1 cat, no blood flow was detected in the left brachial artery with a Doppler ultrasonic flow detector, whereas blood flow in the right brachial artery was easily documented. In the other cat, the right femoral pulse was not palpable. Neither cat had any echocardiographic evidence of cardiac disease. In both cats, treatment was primarily supportive. One cat died, and the other was euthanatized. At necropsy, lung lobe consolidation was seen. Microscopically, there was multifocal infiltration of the lung parenchyma with cuboidal to columnar neoplastic epithelial cells. Neoplastic epithelial cells of similar morphology were identified in nodular masses in sections of muscle, and intravascular tumor emboli were identified obliterating small and large arterioles. Immunohistochemical staining of pulmonary and muscular tissue for pan-cytokeratin antigen revealed intense cytoplasmic staining of neoplastic cells. Staining for factor VIII-related antigen confirmed that clusters of neoplastic cells represented intravascular emboli. Clinical signs in the cats were attributed to arterial occlusion by tumor emboli.

Ischemic neuromyopathy due to peripheral arterial embolization of an adenocarcinoma in a cat

A case of peripheral arterial tumor embolization in a cat is described. The cat presented with signs of aortic thromboembolism, including decreased peripheral pulse quality, pallor, and coolness of the distal limbs, as well as proprioceptive deficits. Thoracic radiographs revealed a cavitary lung mass; echocardiography was unremarkable. Cytologic evaluation of aspirates of the mass suggested malignancy. The left hindlimb was amputated, and histopathology confirmed embolization of an adenocarcinoma. Although rare, peripheral arterial tumor embolization should be considered as a differential in cats presenting with signs of thromboembolic disease.