How Many Lymph Nodes Are Enough? Assessing the Adequacy of Lymph Node Yield for Staging in Favorable Histology Wilms Tumor

© 2019 Elsevier Inc. Purpose: Current investigational priorities in the treatment of favorable histology Wilms tumor (FHWT) center on accurate staging and risk-stratification. The extent of lymph node (LN) sampling has not been clearly defined; its importance cannot be overstated as it guides adjuvant therapy. The identification of a minimum LN yield to minimize the risk of harboring occult metastatic disease could help development of surgical guidelines. This study focuses on using the beta-binomial distribution to estimate the risk of occult metastatic disease in patients with FHWT. Materials & methods: The National Cancer Database was queried for patients with unilateral FHWT from 2004 to 2013. Data were used to characterize nodal positivity for patients who underwent surgery and had ≥ 1 positive LN and ≥ 2 LNs examined. The probability of missing a positive LN (i.e., false negative) for a given LN yield was calculated using an empirical estimation and the beta-binomial model. Patients were then stratified by tumor size. Results: 422 patients met study criteria. To limit the chance of missing a positive LN to ≤ 10%, the empirical estimation and beta-binomial model estimated that 6 and 10 LNs needed to be sampled, respectively. Tumor size did not influence the result. Internal validation showed little variation to maintain a false negative rate ≤ 10%. Conclusions: Using mathematical modeling, it appears that the desired LN yield in FHWT to reduce the risk of false-negative LN sampling to ≤ 10% is between 6 and 10. The current analysis represents an objective attempt to determine the desired surgical approach to LN sampling to accurately stage patients with FHWT. Level of evidence: I

Optimization of percutaneous biopsy for diagnosis and pretreatment risk assessment of neuroblastoma

Background: Image-guided percutaneous core needle biopsy (PCNB) is increasingly utilized to diagnose solid tumors. The objective of this study is to determine whether PCNB is adequate for modern biologic characterization of neuroblastoma. Procedure: A multi-institutional retrospective study was performed by the Pediatric Surgical Oncology Research Collaborative on children with neuroblastoma at 12 institutions over a 3-year period. Data collected included demographics, clinical details, biopsy technique, complications, and adequacy of biopsies for cytogenetic markers utilized by the Children\u27s Oncology Group for risk stratification. Results: A total of 243 children were identified with a diagnosis of neuroblastoma: 79 (32.5%) tumor excision at diagnosis, 94 (38.7%) open incisional biopsy (IB), and 70 (28.8%) PCNB. Compared to IB, there was no significant difference in ability to accurately obtain a primary diagnosis by PCNB (95.7% vs 98.9%, P =.314) or determine MYCN copy number (92.4% vs 97.8%, P =.111). The yield for loss of heterozygosity and tumor ploidy was lower with PCNB versus IB (56.1% vs 90.9%, P \u3c.05; and 58.0% vs. 88.5%, P \u3c.05). Complications did not differ between groups (2.9 % vs 3.3%, P = 1.000), though the PCNB group had fewer blood transfusions and lower opioid usage. Efficacy of PCNB was improved for loss of heterozygosity when a pediatric pathologist evaluated the fresh specimen for adequacy. Conclusions: PCNB is a less invasive alternative to open biopsy for primary diagnosis and MYCN oncogene status in patients with neuroblastoma. Our data suggest that PCNB could be optimized for complete genetic analysis by standardized protocols and real-time pathology assessment of specimen quality

Optimization of percutaneous biopsy for diagnosis and pretreatment risk assessment of neuroblastoma

BackgroundImage- guided percutaneous core needle biopsy (PCNB) is increasingly utilized to diagnose solid tumors. The objective of this study is to determine whether PCNB is adequate for modern biologic characterization of neuroblastoma.ProcedureA multi- institutional retrospective study was performed by the Pediatric Surgical Oncology Research Collaborative on children with neuroblastoma at 12 institutions over a 3- year period. Data collected included demographics, clinical details, biopsy technique, complications, and adequacy of biopsies for cytogenetic markers utilized by the Children’s Oncology Group for risk stratification.ResultsA total of 243 children were identified with a diagnosis of neuroblastoma: 79 (32.5%) tumor excision at diagnosis, 94 (38.7%) open incisional biopsy (IB), and 70 (28.8%) PCNB. Compared to IB, there was no significant difference in ability to accurately obtain a primary diagnosis by PCNB (95.7% vs 98.9%, P = .314) or determine MYCN copy number (92.4% vs 97.8%, P = .111). The yield for loss of heterozygosity and tumor ploidy was lower with PCNB versus IB (56.1% vs 90.9%, P < .05; and 58.0% vs. 88.5%, P < .05). Complications did not differ between groups (2.9 % vs 3.3%, P = 1.000), though the PCNB group had fewer blood transfusions and lower opioid usage. Efficacy of PCNB was improved for loss of heterozygosity when a pediatric pathologist evaluated the fresh specimen for adequacy.ConclusionsPCNB is a less invasive alternative to open biopsy for primary diagnosis and MYCN oncogene status in patients with neuroblastoma. Our data suggest that PCNB could be optimized for complete genetic analysis by standardized protocols and real- time pathology assessment of specimen quality.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154667/1/pbc28153_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154667/2/pbc28153.pd

Pancreaticoduodenectomy for the treatment of pancreatic neoplasms in children: A Pediatric Surgical Oncology Research Collaborative study

BackgroundTo better characterize short- term and long- term outcomes in children with pancreatic tumors treated with pancreaticoduodenectomy (PD).MethodsPatients 21 years of age or younger who underwent PD at Pediatric Surgical Oncology Collaborative (PSORC) hospitals between 1990 and 2017 were identified. Demographic, clinical information, and outcomes (operative complications, long- term pancreatic function, recurrence, and survival) were collected.ResultsSixty- five patients from 18 institutions with a median age of 13 years (4 months- 22 years) and a median (IQR) follow- up of 2.8 (4.3) years were analyzed. Solid pseudopapillary tumor of the pancreas (SPN) was the most common histology. Postoperative complications included pancreatic leak in 14% (n = 9), delayed gastric emptying in 9% (n = 6), marginal ulcer in one patient, and perioperative (30- day) death due to hepatic failure in one patient. Pancreatic insufficiency was observed in 32% (n = 21) of patients, with 23%, 3%, and 6% with exocrine, or endocrine insufficiencies, or both, respectively. Children with SPN and benign neoplasms all survived. Overall, there were 14 (22%) recurrences and 11 deaths (17%). Univariate analysis revealed non- SPN malignant tumor diagnosis, preoperative vascular involvement, intraoperative transfusion requirement, pathologic vascular invasion, positive margins, and need for neoadjuvant chemotherapy as risk factors for recurrence and poor survival. Multivariate analysis only revealed pathologic vascular invasion as a risk factor for recurrence and poor survival.ConclusionThis is the largest series of pediatric PD patients. PD is curative for SPN and benign neoplasms. Pancreatic insufficiency is the most common postoperative complication. Outcome is primarily associated with histology.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156233/2/pbc28425.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156233/1/pbc28425_am.pd

Pancreaticoduodenectomy for the treatment of pancreatic neoplasms in children: A Pediatric Surgical Oncology Research Collaborative study

Background: To better characterize short-term and long-term outcomes in children with pancreatic tumors treated with pancreaticoduodenectomy (PD). Methods: Patients 21 years of age or younger who underwent PD at Pediatric Surgical Oncology Collaborative (PSORC) hospitals between 1990 and 2017 were identified. Demographic, clinical information, and outcomes (operative complications, long-term pancreatic function, recurrence, and survival) were collected. Results: Sixty-five patients from 18 institutions with a median age of 13 years (4 months-22 years) and a median (IQR) follow-up of 2.8 (4.3) years were analyzed. Solid pseudopapillary tumor of the pancreas (SPN) was the most common histology. Postoperative complications included pancreatic leak in 14% (n = 9), delayed gastric emptying in 9% (n = 6), marginal ulcer in one patient, and perioperative (30-day) death due to hepatic failure in one patient. Pancreatic insufficiency was observed in 32% (n = 21) of patients, with 23%, 3%, and 6% with exocrine, or endocrine insufficiencies, or both, respectively. Children with SPN and benign neoplasms all survived. Overall, there were 14 (22%) recurrences and 11 deaths (17%). Univariate analysis revealed non-SPN malignant tumor diagnosis, preoperative vascular involvement, intraoperative transfusion requirement, pathologic vascular invasion, positive margins, and need for neoadjuvant chemotherapy as risk factors for recurrence and poor survival. Multivariate analysis only revealed pathologic vascular invasion as a risk factor for recurrence and poor survival. Conclusion: This is the largest series of pediatric PD patients. PD is curative for SPN and benign neoplasms. Pancreatic insufficiency is the most common postoperative complication. Outcome is primarily associated with histology

Understanding the Value of Tumor Markers in Pediatric Ovarian Neoplasms

Purpose The purpose of this study was to determine the diagnostic accuracy of tumor markers for malignancy in girls with ovarian neoplasms. Methods A retrospective review of girls 2–21 years who presented for surgical management of an ovarian neoplasm across 10 children's hospitals between 2010 and 2016 was performed. Patients who had at least one concerning feature on imaging and had tumor marker testing were included in the study. Sensitivity, specificity, and negative and positive predictive values (PPV) of tumor markers were calculated. Results Our cohort included 401 patients; 22.4% had a malignancy. Testing for tumor markers was inconsistent. AFP had high specificity (98%) and low sensitivity (42%) with a PPV of 86%. The sensitivity, specificity, and PPV of beta-hCG was 44%, 76%, and 32%, respectively. LDH had high sensitivity (95%) and Inhibin A and Inhibin B had high specificity (97% and 92%, respectively). Conclusions Tumor marker testing is helpful in preoperative risk stratification of ovarian neoplasms for malignancy. Given the variety of potential tumor types, no single marker provides enough reliability, and therefore a panel of tumor marker testing is recommended if there is concern for malignancy. Prospective studies may help further elucidate the predictive value of tumor markers in a pediatric ovarian neoplasm population

Current state of renal tumor surgery among pediatric surgeons and pediatric urologists: A survey of American Pediatric Surgical Association (APSA) and Society for Pediatric Urology (SPU) members

© 2017 Journal of Pediatric Urology Company Introduction: Anecdotally, renal tumor (RT) surgery makes up a limited portion of the practice for most pediatric urologists and pediatric surgeons. Data are lacking on the current perceptions of RT surgery, both volume of surgery and issues related to surgical practice, among pediatric surgeons (PS) and pediatric urologists (PU). Objectives: To describe practice patterns of pediatric renal tumor (RT) surgery and identify factors related to higher reported volumes of RT surgery. Study design: The survey was developed and pilot-tested by the Children\u27s Oncology Group (COG) RT surgery committee. The survey was distributed to APSA and SPU members. Logistic regression was performed to correlate surgeon-reported factors with higher reported volumes of RT surgery. Results: The survey was sent to 1,282 APSA and 426 SPU members, 367 (21.5%) surveys were completed from eligible responders, 244 (65.2%) and 123 (32.9%) from APSA and SPU invitations, respectively. Overall, 33.9% reported being part of a practice group in which RT surgical care is sub-specialized. A majority (50.7%) of respondents reported personally performing one to two RT surgeries annually, and 16.7% reported performing none. Multivariate logistic regression identified the following significant factors associated with increased individual RT surgical volume: group sub-specialization, COG/SIOP membership, regular tumor board attendance, and annual institutional volume \u3e10 RT surgeries (Table). Accurate responses on the need for lymph node (LN) sampling in RT surgery were reported by 89.9%. Overall, 15.8% and 24.5% of respondents failed to correctly correlate local stage III disease in Wilms tumor (WT) with open or percutaneous biopsy, respectively (p \u3c 0.001). Discussion: While we found that reported RT surgery volume is low among both pediatric urologists and surgeons, we did identify surgeon-specific factors which correlated with higher RT surgical volume. Interested pediatric urologists and surgeons may use these data to tailor their practice if their goal is to increase RT surgery volume. Additionally, based on less than ideal rates of correct responses to nuance in the staging and treatment of WT, there are clear opportunities to increase education in this content area. However, the study is limited by use of a non-validated survey instrument and the relatively low response rates. Conclusion: Reported individual RT surgery volume is low. Factors associated with increased volume include sub-specialty practice, tumor board involvement, and higher institutional volume. Responses on LN sampling and biopsy in WT demonstrate opportunities for educational initiatives. [Table presented

Patterns of lymph node sampling and the impact of lymph node density in favorable histology Wilms tumor: An analysis of the national cancer database

© 2017 Journal of Pediatric Urology Company Introduction: There is controversy about the role of lymph node (LN) sampling or dissection in the management of favorable histology (FH) Wilms tumor (WT), specifically how it performed and how it may impact survival. Objective: The objective of this study was to analyze factors affecting LN sampling patterns and the impact of LN yield and density (number of positive LNs/LNs examined) on overall survival (OS) in patients with advanced-stage favorable histology Wilms tumor (FHWT). Methods: The National Cancer Database (NCDB) was queried for patients with FHWT during 2004–2013. Demographic, clinical and OS data were abstracted for those who underwent surgical resection. Poisson regression was performed to analyze how factors influenced LN yield. Patients with positive LNs had LN density calculated and were further analyzed. Results: A total of 2340 patients met criteria, with a median age at diagnosis of 3 years (range 0–78 years). The median number of LNs examined was three (range 0–87). Lymph node yield was affected by age, race, insurance, tumor size, laterality, advanced stage, LN positivity, and institutional volume. A total of 390 (16.6%) patients had LN-positive disease. Median LN density for these LN-positive patients was 0.38 (range 0.02–1) (Summary Figure). Estimated 5-year OS was significantly improved for those with LN density ≤0.38 vs. \u3e0.38 (94% vs. 84.6%, P = 0.012). In this population, on multivariate analysis, age and LN density were significant predictors of OS. Discussion: It is difficult to compile large numbers of cases in rare diseases like WT, and fortunately a large administrative database such as the NCDB can serve as a great resource. However, administrative data come with inherent limitations such as missing data and inability to account for a variety of factors that may influence LN yield and/or OS (specimen designation, pathologist experience, surgeon experience/volume, institutional Children\u27s Oncology Group (COG) association, etc.). In this specific disease, the American Joint Committee on Cancer staging (captured by the NCDB) is different than the COG WT staging system that is used clinically, and the NCDB does not capture oncologic outcomes beyond OS. Conclusions: In a review of the NCDB, various factors associated with LN yield and observed LN density were identified to be significantly associated with OS in patients with LN-positive FHWT. This reinforces the need for adequate LN sampling at the time of WT surgery, to maximize surgical disease control. It was proposed that LN density as a metric may allow for improved risk-stratification, and possibly allow for therapeutic reduction in a sub-set of patients with low LN density.[Figure presented

Presacral masses and sacrococcygeal teratomas in patients with and without anorectal malformations: A single institution comparative study

© 2018 Elsevier Inc. Background: Despite variability at presentation, presacral masses in patients with and without anorectal malformations (ARM) appear histologically similar. The purpose of this study was to identify differences in oncologic outcomes between these two groups. Methods: A retrospective review was performed utilizing our institutional cancer and colorectal and pelvic reconstruction databases for patients with presacral masses and sacrococcygeal teratomas between 1990 and 2017. Data captured included age at surgical resection, type of ARM, tumor location within the pelvis, tumor histopathology, tumor size, adjuvant chemotherapy, recurrence, and follow-up. Results: Forty-six patients comprised our cohort, of whom 12 had an ARM. The median age was older at resection for those with an ARM (1.4 years; range 1 day to 29.4 years) compared to those without an ARM (9 days; range 0 days to 6.9 years) (p = 0.01). The mean tumor size was 2.5 cm in patients with an ARM compared to 6.0 cm in patients without an ARM (p = 0.036). All patients with ARM had exclusively intrapelvic tumors, and histopathology included mature teratoma (8), yolk sac tumor (1), lipoma (1), and unknown (2). Tumor location for patients with sacral and presacral masses without ARM included exclusively extrapelvic (10), primarily extrapelvic with large intrapelvic component (7), primarily intrapelvic with extrapelvic component (1), exclusively intrapelvic (8), and unknown (8). Histopathology for patients with presacral masses without ARM included mature teratoma (20), immature teratoma (7), yolk sac tumor (3), ganglioneuroma (1), neuroblastoma (1), benign epithelial cyst (1), and unknown (1). Tumor recurrence rate was similar between patients with ARM (n = 3, 25%) and those without an ARM (n = 5, 15%) (p = 0.41). The 5-year event free survival was 65% (95% CI: 25%–87%) in the group with ARM and 81% (95% CI: 60%–92%) in the group without ARM (p = 0.44). Conclusion: Sacral and presacral masses in patients with ARM are resected at a later age and are more likely to be intrapelvic. They appear histologically similar and have similar rates of recurrence and malignancy when compared to patients without ARM. Level of Evidence: III Type of Study: Retrospective comparative study

Outcome analysis of stage I epithelial-predominant favorable-histology Wilms tumors: A report from Children\u27s Oncology Group study AREN03B2.

BACKGROUND: Stage 1 epithelial-predominant favorable histology Wilms tumors (EFHWT) have long been suspected to have an excellent outcome. This study investigates the clinical and pathologic features of patients with stage 1 EFHWT in order to better evaluate the potential for reduction of chemotherapy and its associated toxicity. METHODS: All patients registered on the COG AREN03B2 study between 2006 and 2017 with stage 1 EFHWT were identified. EFHWT were defined as tumors with at least 66% epithelial differentiation, regardless of degree of differentiation. Clinical information was abstracted from COG records. Event free survival (EFS) and overall survival (OS) were calculated and compared between groups based on age and therapy. RESULTS: The 4-year EFS was 96.2% (95% CI; 92 – 100%) and OS was 100%; EFS and OS did not statistically significantly differ based on age at diagnosis (>48 months vs 95% EFS and OS. These data support the utility of investigating the treatment of Stage I EFHWT with observation alone following nephrectomy