Role of Interventional Radiology in Pediatric Cancer Patients.

PURPOSE OF REVIEW: Pediatric interventional radiology (IR) is a growing subspecialty. Here, we review the current role of IR in children with cancer, which uses imaging such as ultrasound, fluoroscopy, and computed tomography to perform minimally invasive procedures. These include biopsy, needle localization, central venous access, thermal ablation, transarterial chemoembolization, transarterial radioembolization with yttrium-90, non-tunneled/tunneled drainage catheter placement, and lymphatic interventions. RECENT FINDINGS: Although locoregional therapies for the treatment of cancer in adults are common, they are less common in children, perhaps due to the relative rarity of cancer in children, their typically better performance status, and paucity of comorbidities. Preliminary results from small-scale studies for ablation, transarterial chemoembolization, and transarterial radioembolization with yttrium-90 used in the front-line armamentarium of curative therapy are encouraging. Pediatric IR offers an array of minimally invasive procedures intended to diagnose and treat pediatric cancer patients. However, more research is required to determine the efficacy of locoregional therapy in children and to define the clinical scenarios where benefit is likely to be optimized.

Successful use of transarterial radioembolization with yttrium-90 (TARE-Y90) in two children with hepatoblastoma.

Primary malignant liver tumors are rare but all require surgical resection as part of therapy with curative intent. A minority of patients have resectable tumors at diagnosis. Chemotherapy has a therapeutic role in hepatoblastoma but only one-third of patients have resectable disease at diagnosis. Two children with hepatoblastoma and suboptimal responses to initial chemotherapy received therapy with transarterial radioembolization utilizing yttrium-90 (TARE-Y90) and had significant response leading to resection and remission. The role of TARE-Y90 needs to be studied further to define its use in primary pediatric liver neoplasms.

Transarterial radioembolization with yttrium-90 of unresectable primary hepatic malignancy in children.

BACKGROUND: Primary malignant liver tumors are rare, accounting for 1% to 2% of all childhood cancers. When chemotherapy fails, transarterial radioembolization with yttrium-90 (TARE-Y90) may offer an alternative therapy as a bridge to surgical resection or liver transplant or for palliation. METHODS: We conducted a retrospective review of 10 pediatric patients with histologically confirmed primary liver malignancy who received treatment with TARE-Y90. RESULTS: The median age at treatment was 5.5 years (range, 2-18 years). Median patient survival from initial diagnosis was 12.5 months (range, 10-28 months), and median patient survival after TARE-Y90 was 4 months (range, 2-20 months). Retreatment was well tolerated in three of 10 patients, with these patients demonstrating the longest survival times (range, 17-20 months). One patient was transplanted 6 weeks after TARE-Y90. By RECIST 1.1 criteria of all target lesions, eight of nine patients had stable disease, and one of nine had progressive disease. By mRECIST criteria (requiring postcontrast arterial phase imaging), two of seven patients had a partial response, four of seven had stable disease, and one of seven had progressive disease. CONCLUSION: TARE-Y90 of unresectable primary liver malignancy is both technically feasible and demonstrates an anticancer effect, and retreatment is well tolerated. TARE-Y90 could be considered as adjunctive therapy in pediatric patients with unresectable hepatic malignancies and could be used as a bridge to surgical resection or liver transplant. More research is required to determine the efficacy of this treatment in children and to define the clinical scenarios where benefit is likely to be optimized.

Technical and nidus-specific factors associated with adequacy of intraprocedural biopsy samples preceding radiofrequency ablation of osteoid osteoma.

PURPOSE: To examine the diagnostic yield of intraprocedural percutaneous biopsy performed at the time of radiofrequency ablation of suspected Osteoid Osteoma (OO) and identify technical and nidus-specific factors associated with diagnostic adequacy. MATERIALS AND METHODS: Following IRB approval, a total of 42 patients (male: 28, female: 14; mean age: 29 years) who underwent intraprocedural biopsy immediately prior to RFA between June 2010 and June 2017 were retrospectively identified. The nidi were located in various locations. The nidi had a mean size of 6.3 mm (range: 3-11 mm, Standard deviation (SD): 2.26). Core biopsies were performed by one of 15 operators. Biopsies were performed with two needle types ranging from 11-G to 15-G with a mean number of samples of 1.8 (range: 1-5, SD: 1.01). Electronic records and imaging were reviewed for demographics, nidus characteristics, biopsy details and diagnostic yield. Multivariate logistic regression of nidus-specific and biopsy-specific factors was performed. RESULTS: A total of 22/42 (52.3%) of the biopsies were adequate for histological diagnosis of OO. For the two experienced operators, the diagnostic yield was 67% (6/9) and 80% (8/10). Biopsy adequacy was significantly correlated with presence of an osteoid matrix (p = 0.03), obtaining >1 core sample (p = 0.03), the needle track passing through the nidus (p = 0.0003) and thinner (2.5 mm) intraprocedural CT slices (p = 0.03). On multivariate analysis, use of thinner intraprocedural CT slices was found to be associated with adequate biopsy (p = 0.02). CONCLUSION: Intraprocedural percutaneous biopsy samples of nidi highly-suspected to be OO at the time of RFA were diagnostic in 52% of patients. Multivariate analysis shows thinner intraprocedural CT slices to be a significantly associated with biopsy adequacy.

Effects of autoshaping procedures on 3H-8-OH-DPAT-labeled 5-HT1a binding and 125I-LSD-labeled 5-HT2a binding in rat brain.

Effects of experience with Pavlovian autoshaping procedures on lever-press autoshaping conditioned response (CR) performance and 3H-8-OH-DPAT-labeled binding of 5-HT(1a) receptors as well as 125I-LSD-labeled binding of 5-HT(2a) receptors were evaluated in four groups of male Long-Evans hooded rats. Two groups of rats (Group Paired High CR and Group Paired Low CR) received Pavlovian autoshaping procedures wherein the presentation of a lever (conditioned stimulus, CS) was followed by the response-independent presentation of food (unconditioned stimulus, US). Rats in Group Paired High CR (n=12) showed more rapid CR acquisition and higher asymptotic levels of lever-press autoshaping CR performance relative to rats in Group Low CR (n=12). Group Omission (n=9) received autoshaping with an omission contingency, such that performing the lever-press autoshaping CR resulted in the cancellation the food US, while Group Random (n=9) received presentations of lever CS and food US randomly with respect to one another. Though Groups Omission and Random did not differ in lever-press autoshaping CR performance, Group Omission showed significantly lower levels of 3H-8-OH-DPAT-labeled 5-HT(1a) binding in post-synaptic areas (frontal cortex, septum, caudate putamen), as well as significantly higher plasma corticosterone levels than Group Random. In addition, Group Random showed higher levels of 3H-8-OH-DPAT-labeled 5-HT(1a) binding in pre-synaptic somatodendritic autoreceptors on dorsal raphe nucleus relative to each of the other three groups. Autoradiographic analysis of 125I-LSD-labeled 5-HT(2a) receptor binding revealed no significant differences between Groups Paired High CR and Paired Low CR or between Groups Omission and Random in any brain regions.

Office CO2 laser turbinoplasty.

We conducted a prospective study of office carbon dioxide (CO(2)) laser turbinoplasty as a treatment for symptoms related to turbinate dysfunction in 58 patients. All patients completed surveys before and 1 month after treatment, and 23 patients completed longer-term follow-up surveys 8 to 24 months postoperatively. The 1-month postoperative assessments demonstrated a trend toward symptom improvement, as many patients reported a decrease in their use of pretreatment medications. Long-term benefit was achieved in 70% of patients. Ten patients underwent pre- and post-treatment biopsies, and histologic evaluation demonstrated minimal tissue alteration following treatment, alleviating concerns of physiological and functional compromise. We conclude that office-based CO(2) laser turbinoplasty is a useful tool for the treatment of disorders related to turbinate dysfunction. We describe one clinician's method of performing office CO(2) laser turbinoplasty, and we report his experience and findings.