Recurrent chondromyxoid fibroma of the distal femur treated with percutaneous cryoablation.

Chondromyxoid fibroma is a rare, benign tumor of the bone with excellent prognosis but a high rate of recurrence. We report a patient presenting with pain and a history of chondromyxoid fibroma of the distal left femur previously treated with multiple prior curettage and bone graft procedures. Magnetic resonance imaging and histopathology indicated a recurrence of tumor. Due to the small size of the tumor recurrence and challenges associated with prior open surgery, the patient underwent cryoablation of the lesion with computed tomography guidance. Follow-up 18 months later indicated a resolution of pain and improvement on magnetic resonance imaging, and no concerns after 20 months. To our knowledge, this is the first reported case of chondromyxoid fibroma treated with cryoablation. This case suggests cryoablation could be considered in the setting of recurrent chondromyxoid fibroma for local tumor control.

Clinical Outcomes following Percutaneous Urinary Diversion for Hemorrhagic Cystitis.

Hemorrhagic cystitis (HC) can lead to severe morbidity in treatment-refractory cases. Percutaneous nephrostomy (PCN) drainage was first described in 1993 as a safe, nonoperative procedure to achieve supravesical urinary diversion and treat severe HC. Despite its early success, subsequent studies in the adult population have been limited. This retrospective case series describes long-term outcomes following PCN placement in 24 patients with refractory HC. The overall technical success of the procedure was 100%. Seventeen of 24 (71%) patients experienced resolution of hematuria. The median time for hematuria resolution after the procedure was 12 days (interquartile range, 7-28 days). Postprocedural HC severity grade significantly decreased from a median Grade 3 to Grade 1 (P < .01). The complications included catheter obstruction, dislodgement, and associated urinary tract infections occurring at rates of 1.0, 1.6, and 1.7 per 1,000 catheter days, respectively. This study of PCN placement demonstrated and further confirmed the effectiveness of urinary diversion in treating refractory HC.

Portal Vein Aneurysm Treated With Trans-Jugular Intrahepatic Porto-Systemic Shunt.

Portal vein aneurysm (PVA) is a rare entity that can lead to hemorrhage or thrombosis. Although there is no standard treatment, most cases can be managed conservatively; intervention is reserved for symptomatic or enlarging aneurysms. For patients who are not surgical candidates due to cirrhosis and portal hypertension, endovascular creation of a trans-jugular intrahepatic porto-systemic shunt (TIPS) is an option to reduce portal venous pressure. This report describes a case of an enlarging PVA successfully treated with TIPS in a patient with cryptogenic cirrhosis.

Spontaneous breast hematoma as a complication of anticoagulation therapy requiring angiography and embolization.

Spontaneous breast hematoma is a rare complication of therapeutic anticoagulation therapy with few cases reported in the literature. We present a case of spontaneous breast hematoma resulting in hypotension and symptomatic anemia. Angiography demonstrated multiple sites of hemorrhage within the breast, which was treated with gelatin sponge embolization. This case highlights the role of interventional radiology in the treatment of breast hematoma, as well as reviews the arterial vascular anatomy of the breast.

Ablation Planning Software for Optimizing Treatment: Challenges, Techniques, and Applications.

Percutaneous ablation can deliver effective anticancer therapy with minimal side effects; however, undertreatment can lead to disease recurrence and overtreatment can lead to unnecessary complications. Ablation planning software can support the procedure during the planning, treatment, and follow-up phases. In this review, 2 examples of microwave ablation software are described with attention to how the software can influence procedural choices. In the future, ablation software will entail larger source datasets and more refined algorithms to better model the in vivo ablation zone. Moreover, ablation simulation has the potential to augment clinical care beyond the interventional suite, such as procedural demonstration for patients, clinical consultation with referring providers, documentation for the medical record, and educational simulation for trainees.

Pulmonary Cryoablation Zones: More Aggressive Ablation Is Warranted In Vivo.

OBJECTIVE: The objective of our study was to determine the effective cryoablation zone when treating pulmonary tumors in vivo and to create pulmonary-specific ablation maps to guide clinical procedure planning. MATERIALS AND METHODS: Ablation volume was measured retrospectively in human patients after pulmonary tumor cryoablation with a triple-freeze protocol. Single-probe ablations were performed with 17-, 14-, and 13-gauge cryoprobes; multiple-probe ablations were performed with two or three 17-gauge probes. Statistical comparisons of ablation volumes to manufacturer reference values were calculated using the Wilcoxon rank-sum test. Comparisons of ablation sizes by the number of probes were evaluated by the Kruskal-Wallis test. RESULTS: Mean volume of in vivo lung ablation with a single 17-gauge cryoprobe measured 3.0 cm3, which is a statistically significant difference compared with the in vitro -20°C isotherm volume of 22.6 cm3 (p < 0.01). Mean ablation volume of larger 13- and 14-gauge cryoprobes were 4.3 and 1.8 cm3, respectively, both of which are smaller than the in vitro -20°C isotherm volume. Mean cryoablation zone was not significantly affected by distance to the pleura (p = 0.54) or distance to a vessel (p = 0.55). Ablation volume was significantly increased (p < 0.01) with the use of multiple cryoprobes, at a rate of a 10.8-cm3 increase per additional probe. The increased ablation zone size was more attributable to increased short-axis width (9.6-mm increase per probe) compared with long-axis length (5.6-mm increase per probe). CONCLUSION: The in vivo effective pulmonary cryoablation zone is significantly smaller than the manufacturer-published in vitro isotherm. Larger ablation margins in lung are best achieved by using multiple cryoprobes.

Clinical Outcomes after Pulmonary Cryoablation with the Use of a Triple Freeze Protocol.

PURPOSE: To elucidate clinical variables associated with safety and efficacy in patients after cryoablation of pulmonary tumors with the use of a triple freeze protocol. MATERIALS AND METHODS: Percutaneous cryoablation of pulmonary tumors was performed using Galil Medical cryoprobes (Arden Hills, Minnesota) with a triple freeze protocol: 67 nodules in 42 patients were treated at a single institution from 2012 to 2016. Average nodule diameter was 1.6 cm (range 0.4-5.9); 13 nodules (19.4%) were pathologically determined to be a primary lung malignancy, whereas 54 (80.6%) were metastatic nodules of extrapulmonary origin. Average patient age was 68.1 years (range 39.6-89.6), and the male-female ratio was 1.3:1. Ipsilateral thoracic surgery, intervention, or radiotherapy had been performed before the first cryoablation in 18 patients (42.9%). Mean imaging follow-up was 326 days (range 9-1,152). RESULTS: Pneumothorax occurred in 19 cases (33.9%), 7 (12.5%) requiring chest tube, the likelihood of which was significantly greater in patients with 3 or more cryoprobes (P < .01). Local tumor recurrence/residual disease occurred in 6 cases (9.0%). Local tumor recurrence was not seen after ablation of nodules measuring <1.0 cm at the time of procedure, a significant difference from the recurrence ratee of 14.3% for nodules measuring ≥1.0 cm (P < .05). Likelihood of tumor recurrence/residual disease did not correlate with tumor pathology, tumor location, or procedural factors. The estimated marginal probabilities of local recurrence were 11.4%, 11.4%, and 38.1% at 1, 2, and 3 years after ablation, respectively. CONCLUSIONS: Cryoablation of pulmonary tumors with the use of a triple freeze protocol is a viable modality with low recurrence and complication rates.

Diagnostic utility of intravenous contrast for MR imaging in pediatric appendicitis.

BACKGROUND: Magnetic resonance imaging (MRI) is increasingly employed as a diagnostic modality for suspected appendicitis in children. However, there is uncertainty as to which MRI sequences are sufficient for safe, timely and accurate diagnosis. Several recent studies have described different MRI protocols, including exams both with and without the use of intravenous contrast. OBJECTIVE: We hypothesized that intravenous contrast may be useful in some patients but could be safely omitted in others. MATERIALS AND METHODS: All MRI examinations (n=112) performed at our institution for evaluating appendicitis in children were retrospectively reevaluated. Exams were reread by pediatric radiologists under three conditions: With postcontrast images, Without postcontrast images, and Without/With - selective use of postcontrast sequences only when needed for diagnostic certainty. Samples were scored as positive, negative or equivocal for appendicitis. Findings were compared to pathological or clinical follow-up in the medical record. RESULTS: Without the use of intravenous contrast yielded more equivocal results (12.4%) compared to With contrast (3.4%). By selectively using postcontrast sequences, the Without/With group yielded fewer equivocal results (1.1%) compared to Without while also reducing contrast use 79.8% compared to the With contrast group. No significant differences in conditional sensitivity or conditional specificity were detected among the three groups. CONCLUSION: MRI diagnosis of acute appendicitis can be performed without contrast for most patients; injection of contrast can be reserved for only those patients with equivocal non-contrast imaging.

Cysteine proteinase-1 and cut protein isoform control dendritic innervation of two distinct sensory fields by a single neuron.

Dendrites often exhibit structural changes in response to local inputs. Although mechanisms that pattern and maintain dendritic arbors are becoming clearer, processes regulating regrowth, during context-dependent plasticity or after injury, remain poorly understood. We found that a class of Drosophila sensory neurons, through complete pruning and regeneration, can elaborate two distinct dendritic trees, innervating independent sensory fields. An expression screen identified Cysteine proteinase-1 (Cp1) as a critical regulator of this process. Unlike known ecdysone effectors, Cp1-mutant ddaC neurons pruned larval dendrites normally but failed to regrow adult dendrites. Cp1 expression was upregulated/concentrated in the nucleus during metamorphosis, controlling production of a truncated Cut homeodomain transcription factor. This truncated Cut, but not the full-length protein, allowed Cp1-mutant ddaC neurons to regenerate higher-order adult dendrites. These results identify a molecular pathway needed for dendrite regrowth after pruning, which allows the same neuron to innervate distinct sensory fields.

Expression of osteoprotegerin from a replicating adenovirus inhibits the progression of prostate cancer bone metastases in a murine model.

Metastatic involvement of the skeleton is a frequent consequence of advanced prostate cancer. These skeletal metastases cause a number of debilitating complications and are refractory to current treatments. New therapeutic options are being explored, including conditionally replicating adenoviruses (CRAds). CRAds are engineered to selectively replicate in and destroy tumor cells and can be 'armed' with exogenous transgenes for enhanced potency. We hypothesized that a CRAd armed with osteoprotegerin (OPG), an inhibitor of osteoclastogenesis, would inhibit the progression of prostate cancer bone metastases by directly lysing tumor cells and by reducing osteoclast activity. Although prostate cancer bone metastases are predominantly osteoblastic in nature, increased osteoclast activity is critical for the growth of these lesions. Ad5-Δ24-sOPG-Fc-RGD is a CRAd that carries a fusion of the ligand-binding domains of OPG and the Fc region of human IgG1 in place of the viral E3B genes. To circumvent low tumor cell expression of the native adenoviral receptor, an arginine-glycine-aspartic acid (RGD) peptide insertion within the viral fiber knob allows infection of cells expressing α(v) integrins. A 24-base pair deletion (Δ24) within viral E1A limits replication to cells with aberrant retinoblastoma cell cycle regulator/tumor suppressor expression. We have confirmed that Ad5-Δ24-sOPG-Fc-RGD replicates within and destroys prostate cancer cells and, in both murine and human coculture models, that infection of prostate cancer cells inhibits osteoclastogenesis in vitro. In a murine model, progression of advanced prostate cancer bone metastases was inhibited by treatment with Ad5-Δ24-sOPG-Fc-RGD but not by an unarmed control CRAd.

Ex vivo transfer of the Hoxc-8-interacting domain of Smad1 by a tropism-modified adenoviral vector results in efficient bone formation in a rabbit model of spinal fusion.

STUDY DESIGN: Ex vivo gene transfer for spinal fusion. OBJECTIVE: This study aimed to evaluate ex vivo transfer of the nuclear-localized Hoxc-8-interacting domain of Smad1 (termed Smad1C) to rabbit bone marrow stromal cells (BMSCs) by a tropism-modified human adenovirus serotype 5 (Ad5) vector as a novel therapeutic approach for spinal fusion. SUMMARY OF BACKGROUND DATA: Novel approaches are needed to improve the success of bone union after spinal fusion. One such approach is the ex vivo transfer of a gene encoding an osteoinductive factor to BMSCs which are subsequently reimplanted into the host. We have previously shown that heterologous expression of the Hoxc-8-interacting domain of Smad1 in the nuclei of osteoblast precursor cells is able to stimulate the expression of genes related to osteoblast differentiation and induce osteogenesis in vivo. Gene delivery vehicles based on human Ad5 are well suited for gene transfer for spinal fusion because they can mediate high-level, short-term gene expression. However, Ad5-based vectors with native tropism poorly transduce BMSCs, necessitating the use of vectors with modified tropism to achieve efficient gene transfer. METHODS: The gene encoding Smad1C was transferred to rabbit BMSCs by an Ad5 vector with native tropism or a vector retargeted to alphav integrins, which are abundantly expressed on rabbit BMSCs. Transduced BMSCs were maintained in osteoblastic differentiation medium for 30 days. Alkaline phosphatase activity was determined and cells stained for calcium deposition. As positive controls for osteogenesis, we used Ad5 vectors expressing bone morphogenetic protein 2. As negative controls, BMSCs were mock-transduced or transduced with an Ad5 vector expressing beta-galactosidase. In an immunocompetent rabbit model of spinal fusion, transduced BMSCs were coated onto absorbable gelatin sponge and implanted between decorticated transverse processes L6 and L7 of 8-week-old female New Zealand white rabbits. Animals were killed 4 weeks after implantation of the sponges, the fusion masses harvested and the area of new bone quantified using image analysis software. RESULTS: The Smad1C-expressing tropism-modified Ad5 vector mediated a significantly higher level of alkaline phosphatase activity and calcium deposition in transduced rabbit BMSCs than all other vectors. The rabbit BMSCs transduced ex vivo with the Smad1C-expressing tropism-modified Ad5 vector mediated a greater amount of new bone formation than BMSCs transduced with any other vector. CONCLUSIONS: Delivery of the Smad1C gene construct to BMSCs by an alphav integrin-targeted Ad5 vector shows promise for spinal fusion and other applications requiring the formation of new bone in vivo.