Unusual cause of filling defect in pulmonary artery: pulmonary artery sarcoma.

Pulmonary artery (PA) sarcoma is an extremely rare malignant tumor of pulmonary artery. It is often misdiagnosed as pulmonary thromboembolism (PTE) because of its clinical and imaging features which are quite similar to PTE. Multimodality diagnostic imaging and recognition of specific imaging characteristics with appropriate clinical suspicion are required to make correct diagnosis. In this report, we present a case of PA sarcoma with imaging and clinical features as well as emphasize significance of using multimodality imaging.

Mathematical modeling reveals how the density of initial tumor and its distance to parent vessels alter the growth trend of vascular tumors.

OBJECTIVES: The aim of this study was to investigate the response of a tumor and parent vessels to stimulating factors in the tumor microenvironment in different configurations. How a tumor grows and induces angiogenesis in different distances of a parent vessel is investigated. Moreover, interstitial fluid pressure and its effects on tumor cell phenotype are considered in the model. METHODS: A multiscale continuum-discrete model of a vascular tumor is utilized to simulate the growth of a cluster of tumor cells positioned in different distances of parent vessels. An agent-based probabilistic angiogenesis model is coupled to a discrete tumor model to simulate branching, anastomosis, blood flow, wall shear stress, and interstitial tumor pressure in which tumor cells are divided to necrotic, hypoxic, and proliferative. RESULTS: Starting the simulations from 9 initial tumor cells, the model proved that tumors grow to a certain size and also reach to a certain distance before being able to induce sprouting. For tumors placed 2 and 2.5 mm away from a parent vessel, initiation of angiogenesis is delayed significantly in comparison with closer distances. For the initial cluster positioned in a distance of 2.5 mm away, first sprout is seen after 47 days. Moreover, dendritic shape of the tumor is seen prior to angiogenesis which is a sign of cells being starved and wandered in the domain to reach the oxygen source. The trend of tumor growth obeys power law function which aligns with the experimental results. DISCUSSION: The mathematical model revealed the importance of geometry and position of an initial tumor cluster in determining the behavior and final architecture of a vascular tumor. As a tumor cell appears in farther distances from a parent vessel, duration of its growth and inducing angiogenesis becomes longer and the chance of suppressing the tumor in the initial days of growth is higher. Also, the importance of angiogenesis in making tumors devastating is again corroborated by mathematical models.

Efficacy and safety of sirolimus in the treatment of vascular anomalies: A systematic review.

OBJECTIVE: The management of vascular anomalies is complex and requires a multidisciplinary team with a combination of medical, surgical, and intervention treatments. Medical treatment is limited and has conflicting results. Off-label use of mammalian target of rapamycin inhibitors shows promising results. The objective of this study was to systematically evaluate the literature published about the efficacy and safety of sirolimus in the treatment of vascular anomalies. METHODS: A systematic review of the published literature was conducted using the PubMed database and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: There were 73 articles included: 2 randomized controlled studies, 2 nonrandomized prospective studies, and 69 retrospective case reports and case series. In total, 373 patients were included. Sirolimus was administered topically to 56 patients and orally to 317 patients. Sirolimus was highly effective in the treatment of vascular tumors associated with Kasabach-Merritt phenomenon (95.5% of the patients clinically improved and 93% had normalization of coagulopathy), venous malformations (size reduction was observed in 88.9% of patients), and lymphatic malformations (clinical improvement in 94.9% of patients). Topical sirolimus results were conflicting. Arteriovenous malformations were not improved by sirolimus. CONCLUSIONS: Low-level evidence suggests that sirolimus can improve the prognosis of vascular anomalies, most notably vascular tumors associated with life-threatening coagulopathy and venous and lymphatic malformations. Further research is needed to establish the benefits of sirolimus in the management of vascular anomalies.

Expression profile of circular RNAs in infantile hemangioma detected by RNA-Seq.

BACKGROUND: Circular RNAs (circRNAs) have emerged as a novel class of widespread non-coding RNAs, and they play crucial roles in various biological processes. However, the characterization and function of circRNAs in infantile hemangioma (IH) remain elusive. METHODS: In this study, we used RNA-Seq and circRNA prediction to study and characterize the circRNAs in IH tissue and a matched normal skin control. Specific circRNAs were verified using real-time polymerase chain reaction. RESULTS AND CONCLUSION: We found that of the 9811 identified circRNAs, 249 candidates were differentially expressed, including 124 upregulated and 125 downregulated circRNAs in the IH group compared with the matched normal skin control group. A set of differentially expressed circRNAs (in particular, hsa_circRNA001885 and hsa_circRNA006612 expression) were confirmed using qRT-PCR. Gene ontology and pathway analysis revealed that compared to matched normal skin tissues, many processes that were over-represented in IH group were related to the binding, protein binding, gap junction, and focal adhesion. Specific circRNAs were associated with several micro-RNAs (miRNAs) predicted using miRanda. Altogether, our findings highlight the potential importance of circRNAs in the biology of IH and its response to treatment.

One-stage surgery for removal of intravascular leiomyomatosis extending to right ventricle.

RATIONALE: Intravascular leiomyomatosis (IVL) is a rare nonmalignant tumor that can be fatal if untreated. PATIENT CONCERNS: A 49-year-old nulliparous Asian woman who underwent hysterectomy and left salpingo-oophorectomy for multiple uterine leiomyomas 18 months prior presented complaining of intermittent palpitation and chest tightness for approximately 1 month. Echocardiography revealed a large mobile tumor mass extending from the inferior vena cava (IVC) to the right atrium that partially obstructed IVC flow and tricuspid inflow. Thoracicabdominopelvic computed tomography revealed a left adnexal tumor (4.8 × 2.5 cm) causing intravascular obstruction extending from the left internal iliac vein to the IVC, right atrium, and right ventricle. DIAGNOSIS: IVL with right heart involvement INTERVENTIONS:: Under cardiopulmonary bypass, a one-stage surgery combining sternotomy and laparotomy was performed. The tumor was approached and extracted via sternotomy, and tumor detachment and removal of residual tumors was accomplished via laparotomy. OUTCOMES: A firm, smooth, and regularly shape tumor 15.5 × 5.5 × 2.5 in size was completely removed and histopathologically confirmed as IVL. The patient tolerated the surgical procedure well and no postoperative complication was noted. LESSONS: We describe a one-stage surgical approach to completely remove an IVL extending to the right ventricle.

Disturbances in blood flow and 'medicine's greatest imitator'.

First described in 1959, intravascular lymphoma (IVL) remains one of the most clinically challenging diagnoses due to its diverse and non-specific clinical manifestations and evasiveness in detection by standard investigations. Indeed, IVL deserves the title of 'medicine's greatest imitator'. We highlight a case of IVL where the diagnosis came too late in the clinical course, detected by random skin biopsy. Clinicians should strongly consider this diagnosis in presentations with persistent symptomatology despite appropriate interventions.

Renal Intravascular Large B-cell Lymphoma: A Case Report and Review of the Literature.

We herein report the case of a 52-year-old woman who consulted us because of a 2-month history of a fever, anorexia and weight loss. A physical examination was unremarkable. The blood count showed mild anemia and lymphopenia, and lactate dehydrogenase was elevated. Creatinine clearance was normal and proteinuria was undetectable. CT showed enlarged kidneys. A bone marrow biopsy was normal. PET-CT showed an intense uptake of 18fluorodeoxyglucose in both kidneys. A kidney biopsy provided the diagnosis of intravascular large B-cell lymphoma (IVLBCL). Kidney-limited IVLBCL without an impairment in the renal function or proteinuria has not been described. We analyzed the 38 published cases of IVLBCL involving the kidney to describe the main features of this entity.

Dominant neurologic symptomatology in intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma (IVLBCL) is a rare variant of extranodal large B-cell lymphoma and it is characterized by selective intravascular proliferation of malignant cells. Typical features of the disease include aggressive behavior, rapid and frequently fatal course. Clinical picture is non-specific and heterogeneous, depending on the affected organ. It is not uncommon that this unique type of lymphoma is diagnosed post mortem. Herein, we report two cases of IVLBCL with neurologic symptomatology. In our clinical study patient 1 was an 80-year-old male with mixed paraparesis of lower extremities and difficulties with sphincter control. Patient 2 (56-year-old male) had vision malfunction, mental status changes and defect in phatic and motor functions. In both cases definite diagnosis was established by histological examination of necroptic material. We propose to include IVLBCL in differential diagnostic considerations in patients presenting with gradually impairing neurological status and spinal cord damage of unknown etiology (Fig. 2, Ref. 9).

Primary angiosarcoma of neck nodes with bony metastasis - A case report.

This is a case of a 30 year old female who presented in February 2012 with a large painless left neck swelling since 5 months. Her biopsy was done but the result was inconclusive. Later on after proper staging workup it was found to be bony metastatic disease. Her repeated biopsy showed spindle cell lesion. She was advised surgery, which was done revealing poorly differentiated angiosarcoma involving 27 out of 33 lymph nodes. Angiosarcoma is an uncommon malignant neoplasm characterized by rapidly proliferating, extensively infiltrating anaplastic cells derived from blood vessels and lining irregular blood-filled spaces. Cutaneous angiosarcoma of the scalp and face is the most common form of angiosarcoma. Angiosarcoma of the cervical lymph node without a primary scalp or oral cavity lesion is a very rare presentation and has been reported only once. Thus, this case reported with bony metastasis can be labeled as the first of its kind.

Advances in Robotic Vena Cava Tumor Thrombectomy: Intracaval Balloon Occlusion, Patch Grafting, and Vena Cavoscopy.

Robotic level III inferior vena cava (IVC) tumor thrombectomy was described recently. We present ongoing robotic advances in this arena in a case series of six patients with Mayo level II-III thrombi who underwent robotic caval thrombectomy, radical nephrectomy, and retroperitoneal lymphadenectomy. In four patients, proximal intra- or retrohepatic IVC control was obtained solely with an intracaval Fogarty balloon catheter; in one patient, robot-guided flexible cystoscopy of the IVC lumen was performed to rule out any residual or secondary skip thrombi. In one patient, the caval wall defect after thrombus excision was reconstructed robotically using a bovine pericardial patch. Finally, a patient with concomitant renal and adrenal tumors had two distinct thrombi of levels I and III; a robotic double thrombectomy was performed. Mean renal tumor size was 8.4cm (±1.6). Four thrombi (66%) were level III. Mean operative time was 6.4h (±1.7); IVC clamp time, 53.5min (±29.8); blood loss, 668ml (±692); and hospital stay, 5.5 d (±3.8). Two patients required blood transfusions. Complications included Clavien grade 1 (n=2), grade 3a (n=1), and grade 5 (n=1). Mean follow-up was 5.8 mo (±4.3). Robotic IVC thrombectomy is a viable alternative to open surgery for appropriately selected cases by experienced teams. PATIENT SUMMARY: We present ongoing robotic surgical advances in a case series of six patients with blood clots in the inferior vena cava. These innovations will help further advance the field.

Effects of microbeam radiation therapy on normal and tumoral blood vessels.

Microbeam radiation therapy (MRT) is a new form of preclinical radiotherapy using quasi-parallel arrays of synchrotron X-ray microbeams. While the deposition of several hundred Grays in the microbeam paths, the normal brain tissues presents a high tolerance which is accompanied by the permanence of apparently normal vessels. Conversely, the efficiency of MRT on tumor growth control is thought to be related to a preferential damaging of tumor blood vessels. The high resistance of the healthy vascular network was demonstrated in different animal models by in vivo biphoton microscopy, magnetic resonance imaging, and histological studies. While a transient increase in permeability was shown, the structure of the vessels remained intact. The use of a chick chorioallantoic membrane at different stages of development showed that the damages induced by microbeams depend on vessel maturation. In vivo and ultrastructural observations showed negligible effects of microbeams on the mature vasculature at late stages of development; nevertheless a complete destruction of the immature capillary plexus was found in the microbeam paths. The use of MRT in rodent models revealed a preferential effect on tumor vessels. Although no major modification was observed in the vasculature of normal brain tissue, tumors showed a denudation of capillaries accompanied by transient increased permeability followed by reduced tumor perfusion and finally, a decrease in number of tumor vessels. Thus, MRT is a very promising treatment strategy with pronounced tumor control effects most likely based on the anti-vascular effects of MRT.

Functional echocardiography in the fetus with non-cardiac disease.

We describe the hemodynamic changes observed in fetuses with extra cardiac conditions such as intrauterine growth restriction, tumors, twin-twin transfusion syndrome, congenital infections, and in fetuses of mothers with diabetes. In most fetuses with mild extra cardiac disease, the alterations in fetal cardiac function remain subclinical. Cardiac function assessment has however helped us to achieve a better understanding of the pathophysiology of these diseases. In fetuses at the more severe end of the disease spectrum, functional echocardiography may help in guiding clinical decision-making regarding the need for either delivery or fetal therapy. The growth-restricted fetus represents a special indication for routine cardiac function assessment, as in utero hemodynamic changes may help optimize the timing of delivery. Moreover, in intrauterine growth restriction, the altered hemodynamics causes cardiovascular remodeling, which can result in an increased risk of postnatal cardiovascular disease.

Radiation induced myxoma of superior vena cava origin presenting as a right atrial mass.

Myxomas are the most common benign cardiac tumors. Myxomas are more common in the left heart chamber than the right side chamber. An extracardiac origin presenting as a right atrial mass is very rare. Right-sided tumors are considerably less common than left-sided tumors, and however myxoma of great vessels origin presenting as right atrial masses are rare but radiation induced villous myxoma in superior vena cava (SVC) is exceedingly rare tumor. A case of radiation induced myxoma originating in a previously undescribed location and presenting as a right atrial mass is reported.

[Resection of leiomyosarcoma of the inferior vena cava].

Experience in treatment of leiomyosarcoma of the retrohepatic segment of the inferior vena cava at any separately taken clinic is scarce. Given a rare nature of the pathology involved, whose diagnosis and management require joint participation of various-specialty physicians, we have considered it wise to present our own clinical case report.

Surgical management of a neuroendocrine tumor of the inferior vena cava.

Neuroendocrine tumors occurring outside of the gastrointestinal tract or lungs are very few, and to find a primary neuroendocrine tumor of the infrahepatic inferior vena cava (IVC) is extremely rare. We present a case of a patient with a large, 7 × 4 cm neuroendocrine tumor of the IVC, where the IVC and renal veins were completely extirpated and not reconstructed. As a result, the liver was anastomosed to the intrapericardial IVC, and the patient relied on collateral drainage. After an initial postoperative period of anasarca and weight gain, she ultimately recovered fully with no evidence of recurrence in the IVC.

Sellar and parasellar intravascular lymphoma mimicking pituitary apoplexy.

BACKGROUND: Intravascular lymphoma (IVL) is a rare subtype of large-cell non-Hodgkin lymphoma, characterized by proliferation of lymphoma cells within the lumina of small vessels. There are no previously reported cases of IVL involving the pituitary gland presenting with neuro-ophthalmic findings. METHODS: A 68-year-old female presented with headache, right third nerve palsy, and Horner syndrome. MRI showed a 1.4-cm sellar mass consistent with a pituitary macroadenoma. Two weeks later, despite treatment with dexamethasone, the patient developed complete bilateral ophthalmoplegia and ptosis. Repeat MRI showed invasion of the clivus and cavernous sinuses, and a transsphenoidal pituitary biopsy was undertaken. RESULTS: The preliminary histopathology was consistent with bland pituitary apoplexy, but subsequent examination of an incidentally biopsied nasal polyp revealed endovascular malignant lymphoid cells that, on further scrutiny, were also present in the pituitary tissue. The diagnosis of IVL was confirmed, and the patient had an excellent clinical and radiological response to cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab (CHOP-R) chemotherapy. CONCLUSION: IVL may involve the pituitary gland, causing sellar mass effect, cavernous sinus infiltration, and pituitary ischemia, mimicking pituitary apoplexy with neuro-ophthalmic features. It can be effectively treated with CHOP-R chemotherapy.