Miriam Harel

Objective pain assessment after ureteral reimplantation: Comparison of open versus robotic approach

INTRODUCTION While open ureteral reimplantation is the gold standard of surgical intervention for vesicoureteral reflux (VUR), minimally invasive approaches offer the potential benefits of decreased postoperative pain, improved cosmesis, and shorter hospital stay and convalescence. Studies comparing open and minimally invasive surgery with respect to postoperative pain in children have been inconclusive. OBJECTIVE We sought to compare postoperative pain in children undergoing open versus robotic ureteral reimplantation by using age-appropriate, validated pain assessment scales. METHODS A prospective cohort of all patients enrolled in an Institutional Review Board-approved VUR surgery registry between July 2010 and February 2013 was analyzed. Patients who underwent endoscopic treatment or who received caudal or epidural anesthesia were excluded. Age-appropriate, validated pain scales ranging from 0 to 10 were utilized for pain assessment. Pain scores and narcotic doses administered on the first postoperative day were analyzed. RESULTS Of the 34 subjects included, 11 underwent open intravesical reimplantation, while 23 patients underwent robotic extravesical reimplantation. Table 1 displays patient characteristics and results of pain assessment. Robotic surgery was associated with lower narcotic requirement compared to open surgery (P < 0.05). The difference in pain scores between the two cohorts approached, but did not reach, statistical significance (P = 0.12). However, the percentage of patients with mild or no pain (57% robotic, 27% open) versus severe pain (9% robotic, 45% open) was notably different between the two cohorts. DISCUSSION Previous studies addressing the effect of surgical modality on pediatric postoperative pain are limited by their reliance on narcotic administration as an indirect surrogate for measuring pain. In the present study, postoperative pain was assessed with narcotic requirements and consistently collected validated pain scores, which more accurately reflect a patients perceived pain. Although there was no significant difference in subjective pain scores between patients undergoing open versus robotic reimplantation, the percentage of patients with mild or no pain (57% robotic, 27% open) versus severe pain (9% robotic, 45% open) was notably different between the two cohorts. This study was limited by a lack of randomization as well as small sample size, which did not allow for age sub-group analysis or small differences to be statistically significant. CONCLUSIONS In the present study, robotic ureteral reimplantation was associated with lower narcotic requirement compared to open surgery, and lower intensity of postoperative pain according to a direct pain assessment tool. Larger sample sizes are necessary to strengthen statistical comparisons.

Future directions in risk stratification and therapy for advanced pediatric genitourinary rhabdomyosarcoma

Rhabdomyosarcoma (RMS) represents the most common soft tissue sarcoma in infants and children and the third most common pediatric solid tumor, accounting for 5% to 15% of all childhood solid tumors. Of these, 15% to 20% arise from the genitourinary tract, with the most common sites originating from the prostate, bladder, and paratesticular regions, followed by the vagina and uterus. Although upfront radical surgery was used at the initiation of Intergroup RMS Study-I (1972-1978), the treatment paradigm has shifted to include initial biopsy with the goal of organ preservation, systemic chemotherapy for all patients, and local control involving surgical resection with or without radiation therapy for most patients. Collaborative group clinical trials have led to dramatic improvement in survival rates from 1960 to 1996 among patients with low- or intermediate-risk disease; however, outcomes appear to have plateaued in more recent years, and the prognosis for patients with metastatic or relapsed/refractory disease remains poor. Current management goals include minimizing toxicity while maintaining the excellent outcomes in low-risk disease, as well as improving outcomes in patients with intermediate- and high-risk disease. Advances in genetic analysis have allowed further refinement in risk stratification of patients. Perhaps the most significant recent development in RMS research was the discovery of an association of alveolar RMS (ARMS) with translocations t(2;13) and t(1;13). Translocation fusion-positive tumors comprise 80% of ARMS and are more aggressive. Fusion-negative ARMS may have a clinical course similar to embryonal RMS. Future Childrens Oncology Group sarcoma studies will likely incorporate fusion status into risk stratification and treatment allocation. Newer radiotherapy modalities hold promise for providing local control of disease while minimizing morbidity. The addition of traditional cytotoxic chemotherapeutic agents does not seem to improve outcomes in high-risk patients. Ultimately, the most substantial progress may arise from further elucidation of genetic and molecular pathways involved in RMS tumor formation in an effort to identify novel, targeted therapeutic approaches.

Antitumor Activity of a Novel Sphingosine-1-Phosphate 2 Antagonist, AB1, in Neuroblastoma

The bioactive lipid sphingosine-1-phosphate (S1P) and its receptors (S1P1–5) play critical roles in many pathologic processes, including cancer. The S1P axis has become a bona fide therapeutic target in cancer. JTE-013 [N-(2,6-dichloro-4-pyridinyl)-2-[1,3-dimethyl-4-(1-methylethyl)-1H-pyrazolo[3,4-b]pyridin-6-yl]-hydrazinecarboxamide], a known S1P2 antagonist, suffers from instability in vivo. Structurally modified, more potent, and stable S1P2 inhibitors would be desirable pharmacological tools. One of the JTE-013 derivatives, AB1 [N-(1H-4-isopropyl-1-allyl-3-methylpyrazolo[3,4-b]pyridine-6-yl)-amino-N′-(2,6-dichloropyridine-4-yl) urea], exhibited improved S1P2 antagonism compared with JTE-013. Intravenous pharmacokinetics indicated enhanced stability or slower clearance of AB1 in vivo. Migration assays in glioblastoma showed that AB1 was slightly more effective than JTE-013 in blocking S1P2-mediated inhibition of cell migration. Functional studies in the neuroblastoma (NB) cell line SK-N-AS showed that AB1 displayed potency at least equivalent to JTE-013 in affecting signaling molecules downstream of S1P2. Similarly, AB1 inhibition of the growth of SK-N-AS tumor xenografts was improved compared with JTE-013. Cell viability assays excluded that this enhanced AB1 effect is caused by inhibition of cancer cell survival. Both JTE-013 and AB1 trended to inhibit (C-C motif) ligand 2 expression and were able to significantly inhibit subsequent tumor-associated macrophage infiltration in NB xenografts. Interestingly, AB1 was more effective than JTE-013 in inhibiting the expression of the profibrotic mediator connective tissue growth factor. The terminal deoxynucleotidyl transferase–mediated digoxigenin-deoxyuridine nick-end labeling assay and cleaved caspase-3 detection further demonstrated that apoptosis was increased in AB1-treated NB xenografts compared with JTE-013. Overall, the modification of JTE-013 to produce the AB1 compound improved potency, intravenous pharmacokinetics, cellular activity, and antitumor activity in NB and may have enhanced clinical and experimental applicability.

Proximal tubule proteins are significantly elevated in bladder urine of patients with ureteropelvic junction obstruction and may represent novel biomarkers: A pilot study

PURPOSE Ureteropelvic junction obstruction (UPJO) is the major cause of hydronephrosis in children and may lead to renal injury and early renal dysfunction. However, diagnosis of the degree of obstruction and severity of renal injury relies on invasive and often inconclusive renal scans. Biomarkers from voided urine that detect early renal injury are highly desirable because of their noninvasive collection and their potential to assist in earlier and more reliable diagnosis of the severity of obstruction. Early in response to UPJO, increased intrarenal pressure directly impacts the proximal tubule brush border. We hypothesize that single-pass, apically expressed proximal tubule brush border proteins will be shed into the urine early and rapidly and will be reliable noninvasive urinary biomarkers, providing the tools for a more reliable stratification of UPJO patients. MATERIALS AND METHODS We performed a prospective cohort study at Connecticut Childrens Medical Center. Bladder urine samples from 12 UPJO patients were obtained prior to surgical intervention. Control urine samples were collected from healthy pediatric patients presenting with primary nocturnal enuresis. We determined levels of NGAL, KIM-1 (previously identified biomarkers), CD10, CD13, and CD26 (potentially novel biomarkers) by ELISA in control and experimental urine samples. Urinary creatinine levels were used to normalize the urinary protein levels measured by ELISA. RESULTS Each of the proximal tubule proteins outperformed the previously published biomarkers. No differences in urinary NGAL and KIM-1 levels were observed between control and obstructed patients (p = 0.932 and p = 0.799, respectively). However, levels of CD10, CD13, and CD26 were significantly higher in the voided urine of obstructed individuals when compared with controls (p = 0.002, p = 0.024, and p = 0.007, respectively) (Figure). CONCLUSIONS Targeted identification of reliable, noninvasive biomarkers of renal injury is critical to aid in diagnosing patients at risk, guiding therapeutic decisions and monitoring treatment efficacy. Proximal tubule brush border proteins are reliably detected in the urine of obstructed patients and may be more effective at predicting UPJO.

Induction of chemokine (C-C motif) ligand 2 by sphingosine-1-phosphate signaling in neuroblastoma.

BACKGROUND/PURPOSE Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. Preliminary data derived from a human angiogenesis array in NB showed that the bioactive lipid sphingosine-1-phosphate (S1P) induced the secretion of several angiogenesis-related proteins including the important inflammatory factor chemokine (C-C motif) ligand 2 (CCL2). In the present study, we investigated the mechanism of S1P-induced CCL2 expression in NB. METHODS Quantitative real-time PCR and CCL2 ELISA were conducted to detect the mRNA expression and protein secretion of CCL2 in NB cells. Gain and loss of function studies were performed by using specific S1PR antagonists, adenoviral transduction and siRNA transfection. Macrophage F4/80 receptor in NB xenografts was detected by quantitative real-time PCR and immunohistochemistry staining. RESULTS S1P induced CCL2 mRNA expression and protein secretion in a time- and concentration-dependent manner in NB cells. Blockade of S1P2 signaling using the selective S1P2 antagonist JTE-013 inhibited S1P-induced CCL2 expression. Overexpression of S1P2 by adenoviral transduction increased CCL2 secretion while knockdown of S1P2 by siRNA transfection decreased S1P-induced CCL2 secretion in NB cells. Macrophage infiltration, as detected by F4/80 staining, was significantly decreased in JTE-013-treated NB xenografts. CONCLUSIONS Taken together, our data for the first time demonstrate that S1P induced the macrophage-recruiting factor CCL2 expression in NB cells via S1P2, providing new insights into the complicated functions of S1P2 in cancer.

Paratesticular Inflammatory Myofibroblastic Tumor in a Pediatric Patient

Although rare, paratesticular inflammatory myofibroblastic tumor (IMT) represents the second most common paratesticular mass after adenomatoid tumor and comprises roughly 6% of such lesions. Only approximately four cases have been reported in patients younger than 18 years of age. We report an incidentally discovered paratesticular IMT in a 17-year-old male successfully treated with wide excision and testis sparing. To our knowledge, no recurrence has been reported after complete excision of paratesticular IMT; however, continued follow-up is recommended.

Nine Year Retrospective Review of Surgical Treatment of Vesicoureteral Reflux: Comparison of Three Approaches

Objective: To analyze our nine-year experience in the surgical management of vesicoureteral reflux (VUR) with open ureteral reimplantation, robotic reimplantation, and endoscopic correction with Deflux. Methods: We retrospectively reviewed all patients undergoing surgical intervention for primary VUR at our institution between 2001 and 2010. Treatment success was defined as complete resolution of VUR on postoperative voiding cystourethrography. Surgeries were performed by four pediatric urologists. All robotic reimplantations were performed by a single surgeon. Categorical comparisons were made using Pearson’s Chi-Square or Fisher’s Exact test, and continuous variables were compared using Mann-Whitney U. Results: One hundred eighty-three patients (287 ureters) were included. Fourteen patients underwent robotic surgery, while the open surgery and Deflux cohorts included 93 and 76 patients, respectively. Due to the significantly smaller sample size of the robotic cohort, statistical comparisons were made only between the open surgery and Deflux cohorts. Postoperative VUR resolution rate was 100% (open), 85% (robotic), and 78.4% (Deflux). Open reimplantation had a significantly higher VUR resolution rate than Deflux (p<0.001). Overall, 13.9% of patients developed contralateral reflux, with no significant differences between the open and Deflux cohorts. Conclusions: In this study, we found significantly higher success rates with open reimplantation versus Deflux. While robotic reimplantation had high success rates and short hospital stays, the smaller sample size limited statistical comparison of this modality to open surgery or Deflux. We continue to enroll patients into a prospective series of all VUR procedures at our institution, which will result in more robust comparisons.

Antitumor activity of a novel S1P 2 antagonist, AB1, in neuroblastoma

The bioactive lipid sphingosine-1-phosphate (S1P) and its receptors (S1P1–5) play critical roles in many pathologic processes, including cancer. The S1P axis has become a bona fide therapeutic target in cancer. JTE-013 [N-(2,6-dichloro-4-pyridinyl)-2-[1,3-dimethyl-4-(1-methylethyl)-1H-pyrazolo[3,4-b]pyridin-6-yl]-hydrazinecarboxamide], a known S1P2 antagonist, suffers from instability in vivo. Structurally modified, more potent, and stable S1P2 inhibitors would be desirable pharmacological tools. One of the JTE-013 derivatives, AB1 [N-(1H-4-isopropyl-1-allyl-3-methylpyrazolo[3,4-b]pyridine-6-yl)-amino-N′-(2,6-dichloropyridine-4-yl) urea], exhibited improved S1P2 antagonism compared with JTE-013. Intravenous pharmacokinetics indicated enhanced stability or slower clearance of AB1 in vivo. Migration assays in glioblastoma showed that AB1 was slightly more effective than JTE-013 in blocking S1P2-mediated inhibition of cell migration. Functional studies in the neuroblastoma (NB) cell line SK-N-AS showed that AB1 displayed potency at least equivalent to JTE-013 in affecting signaling molecules downstream of S1P2. Similarly, AB1 inhibition of the growth of SK-N-AS tumor xenografts was improved compared with JTE-013. Cell viability assays excluded that this enhanced AB1 effect is caused by inhibition of cancer cell survival. Both JTE-013 and AB1 trended to inhibit (C-C motif) ligand 2 expression and were able to significantly inhibit subsequent tumor-associated macrophage infiltration in NB xenografts. Interestingly, AB1 was more effective than JTE-013 in inhibiting the expression of the profibrotic mediator connective tissue growth factor. The terminal deoxynucleotidyl transferase–mediated digoxigenin-deoxyuridine nick-end labeling assay and cleaved caspase-3 detection further demonstrated that apoptosis was increased in AB1-treated NB xenografts compared with JTE-013. Overall, the modification of JTE-013 to produce the AB1 compound improved potency, intravenous pharmacokinetics, cellular activity, and antitumor activity in NB and may have enhanced clinical and experimental applicability.

Antitumor activity of a novel S1P2 antagonist, AB1, in neuroblastoma

The bioactive lipid sphingosine-1-phosphate (S1P) and its receptors (S1P1–5) play critical roles in many pathologic processes, including cancer. The S1P axis has become a bona fide therapeutic target in cancer. JTE-013 [N-(2,6-dichloro-4-pyridinyl)-2-[1,3-dimethyl-4-(1-methylethyl)-1H-pyrazolo[3,4-b]pyridin-6-yl]-hydrazinecarboxamide], a known S1P2 antagonist, suffers from instability in vivo. Structurally modified, more potent, and stable S1P2 inhibitors would be desirable pharmacological tools. One of the JTE-013 derivatives, AB1 [N-(1H-4-isopropyl-1-allyl-3-methylpyrazolo[3,4-b]pyridine-6-yl)-amino-N′-(2,6-dichloropyridine-4-yl) urea], exhibited improved S1P2 antagonism compared with JTE-013. Intravenous pharmacokinetics indicated enhanced stability or slower clearance of AB1 in vivo. Migration assays in glioblastoma showed that AB1 was slightly more effective than JTE-013 in blocking S1P2-mediated inhibition of cell migration. Functional studies in the neuroblastoma (NB) cell line SK-N-AS showed that AB1 displayed potency at least equivalent to JTE-013 in affecting signaling molecules downstream of S1P2. Similarly, AB1 inhibition of the growth of SK-N-AS tumor xenografts was improved compared with JTE-013. Cell viability assays excluded that this enhanced AB1 effect is caused by inhibition of cancer cell survival. Both JTE-013 and AB1 trended to inhibit (C-C motif) ligand 2 expression and were able to significantly inhibit subsequent tumor-associated macrophage infiltration in NB xenografts. Interestingly, AB1 was more effective than JTE-013 in inhibiting the expression of the profibrotic mediator connective tissue growth factor. The terminal deoxynucleotidyl transferase–mediated digoxigenin-deoxyuridine nick-end labeling assay and cleaved caspase-3 detection further demonstrated that apoptosis was increased in AB1-treated NB xenografts compared with JTE-013. Overall, the modification of JTE-013 to produce the AB1 compound improved potency, intravenous pharmacokinetics, cellular activity, and antitumor activity in NB and may have enhanced clinical and experimental applicability.