Immune expression in children with Wilms tumor: a pilot study

BACKGROUND

Given improvements in multimodality therapy, survival among children with Wilms tumor (WT) exceeds 90%. However, 15% of children with favorable histology and 50% of children with anaplastic WT experience recurrence or progression. Of patients with advanced disease, only 50% survive to adulthood. In adult malignancies (including renal tumors), patient survival has improved with the advent of immunotherapy. However, little is known about the immune microenvironment of WT, making the potential role of immunotherapy unclear.

OBJECTIVE

The objective of the study is to perform an exploratory, descriptive analysis of the immune milieu in WT.

STUDY DESIGN

Between 2016 and 2017, all pediatric patients with WT, some of whom received neoadjuvant chemotherapy, underwent ex vivo wedge biopsy at the time of nephrectomy. The fresh tumor tissue and peripheral blood samples were analyzed for infiltrating immune infiltrate and effector cells using flow cytometry. Immunohistochemistry was performed for CD4, CD8, and PD-L1 expression. Matched blood samples were obtained for each patient, and circulating immune cells were analyzed by flow cytometry.

RESULTS

A total of six patients were enrolled. One patient with neuroblastoma was excluded. The remaining five patients included the following: two with unilateral WT (resected before chemotherapy), two with bilateral WT (resected after neoadjuvant chemotherapy), and one with Denys-Drash syndrome, end-stage renal disease, and history of WT in the contralateral kidney. Immune analysis showed that WT were infiltrated by immune cells regardless of chemotherapy status. CD8 and CD4 T cells were present in the tumor tissue and exhibited an activated phenotype. Elevated levels of natural killer (NK) cells were observed in the tumors (Figure). Immune checkpoint PD-L1 was also found expressed in one of the tumors stained.

DISCUSSION

In this pilot study, it was found that WTs were infiltrated by immune cells (CD45+) both before and after chemotherapy. Elevated levels of NK cells infiltrating the tumor specimens, which were quantitatively increased compared with levels of NK cells circulating in the blood, were noted. T cells, particularly CD4+ and CD8+ T cells, were present in tumor specimens. Tumor-infiltrating CD4 and CD8 T cells displayed an activated phenotype as defined by increased expression of human leukocyte antigen-DR isotype (HLA-DR), programmed cell death protein 1 (PD1), and CD57. Together, these findings suggest that WT microenvironment is immune engaged and may be susceptible to immunotherapy similar to other malignancies.

CONCLUSIONS

These pilot data suggest an immune-engaged tumor microenvironment is present within WT. This implies that WT may be susceptible to immunotherapy similar to adult renal tumors and other adult malignancies. Follow-up studies are currently underway.

Evaluation of the contralateral inguinal ring in clinically unilateral inguinal hernia: a systematic review and meta-analysis

PURPOSE

The management of the contralateral inguinal canal in children with clinical unilateral inguinal hernia is controversial. Our objective was to systematically review the literature regarding management of the contralateral inguinal canal.

METHODS

We searched MEDLINE, EMBASE, and Cochrane databases (1940-2011) using 'hernia' and 'inguinal' and either 'pediatric,' 'infant,' or 'child,' to identify studies of pediatric (age ≤21 years) patients with inguinal hernia. Among clinical unilateral hernia patients, we assessed the number of cases with contralateral patent processus (CPP) and incidence of subsequent clinical metachronous contralateral hernia (MCH). We evaluated three strategies for contralateral management: expectant management, laparoscopic evaluation or pre-operative ultrasound. Pooled estimates of MCH or CPP were generated with random effects by study when heterogeneity was found (I(2) > 50 %, or Cochrane's Q p ≥ 0.10).

RESULTS

We identified 2,477 non-duplicated studies, 129 of which met our inclusion criteria and had sufficient information for quantitative analysis. The pooled incidence of MCH after open unilateral repair was 7.3 % (95 % CI 6.5-8.1 %). Laparoscopic examination identified CPP in 30 % (95 % CI 26-34 %). Lower age was associated with higher incidence of CPP (p < 0.01). The incidence of MCH after a negative laparoscopic evaluation was 0.9 % (95 % CI 0.5-1.3 %). Significant heterogeneity was found in studies and pooled estimates should be interpreted with caution.

CONCLUSIONS

The literature suggests that laparoscopically identified CPP is a poor indicator of future contralateral hernia. Almost a third of patients will have a CPP, while less than one in 10 will develop MCH when managed expectantly. Performing contralateral hernia repair in patients with CPP results in overtreatment in roughly 2 out of 3 patients.

Evaluation of the United States pediatric urology workforce and fellowships: a series of surveys performed in 2006-2010

OBJECTIVE

In the US, there has been an evolution in the practice of pediatric urology from a primary academic sub-specialty focused on reconstruction of major congenital genitorurinary abnormalities to a mixed academic and private practice that serves as the primary care giver for all pediatric urologic concerns. The estimated manpower needs were unable to be resolved, due to our inability to determine the impact of sub-specialty certification on referral patterns, along with the failure to embrace the use of physician extenders. Here, we review a series of surveys performed in 2006-2010 regarding the sub-specialty of pediatric urology.

MATERIALS AND METHODS

The four surveys focused on workforce needs, appraised the financial impact of educational debt on the pediatric urology community, and evaluated concerns of the current fellows in training.

RESULTS

The median financial income for a pediatric urologist, the resident's educational debt load, and a desire of the fellows to have an open dialog with the urologic community regarding the merits of the research year are revealed.

CONCLUSION

We have identified that the ability to recruit fellows into our field is dependent upon a combination of factors: interest in the field, job availability in relationship to geographic locations, mentoring, concerns regarding financial/familial hardships encountered during a 2-year fellowship, and the lack of increased financial reimbursement for the extra training required.

Lung transplantation for cystic fibrosis patients with Burkholderia cepacia complex. Survival linked to genomovar type

The number of cystic fibrosis (CF) patients undergoing lung transplant has risen over the past decade, because of a clear-cut survival benefit. However, patients with Burkholderia cepacia complex are often excluded from transplantation because of increased mortality. To determine the influence of B. cepacia complex genomovar type on transplant outcome, we undertook a retrospective study in 121 CF patients transplanted at UNC. Twenty-one and three patients, respectively, were infected pre- or postoperatively with B. cepacia complex. All posttransplant acquisitions were successfully treated. However, excess mortality occurred over the first 6 postoperative months in those infected preoperatively with B. cepacia complex compared with those not infected (33% versus 12%, p = 0.01). The 1-, 3-, and 5-yr survival were significantly lower in the B. cepacia complex cohort. Of the patients infected preoperatively, genomovar III patients were at the highest risk of B. cepacia complex-related mortality (5 of 12 versus 0 of 8, one isolate not typed; p = 0.035). Each of the B. cepacia complex-related deaths was caused by a unique genotype as determined by pulsed-field gel electrophoresis. All isolates were negative for the cable pilin gene. These results warrant a multicenter analysis of B. cepacia complex-infected patients with genomovar-typing to confirm that genomovar III patients are at highest risk for post-transplant complications.