Indocyanine green-guided nephron-sparing surgery for pediatric renal tumors

BACKGROUND

Indocyanine green (ICG), a water-soluble tricarbocyanine fluorophore, is being increasingly used for tumor localization based on its passive intra-tumoral accumulation due to enhanced permeability and retention in tumor tissue. Therefore, we hypothesized that ICG can provide contrast to facilitate accurate, real-time recognition of renal tumors at the time of nephron-sparing surgery in children.

METHODS

This retrospective study examined the feasibility of ICG in guiding nephron-sparing surgery for pediatric renal tumors.

RESULTS

We reviewed the medical records of 8 pediatric patients with renal tumors in 12 kidneys. Intraoperative localization of tumor with near infrared guidance was successful in all 12 kidneys. However, we consistently found an inverse pattern of near infrared signal in which the normal kidney demonstrated increased fluorescent signal relative to the kidney tumor.

CONCLUSIONS

Fluorescence-guided renal tumor delineation is unique because it has an inverse pattern of near infrared signal in which the normal kidney demonstrates increased signal relative to the adjacent tumor. Nevertheless fluorescence-guided distinguishing of renal tumor from surrounding normal kidney is feasible.

Techniques to avoid hypothermic circulatory arrest in the management of renal tumor with right atrium extension in children

Clear cell sarcoma of the kidney is a rare variety of renal tumor accounting for less than 5% of all pediatric renal tumors. Cardiopulmonary bypass along with hypothermic circulatory arrest is frequently used for management of tumor thrombus extending into supra-hepatic inferior vena cava and right atrium. In this paper, we present a strategy of avoiding circulatory arrest and hypothermia and thereby fast-tracking the recovery in managing a case of clear cell sarcoma of the kidney in a 3.5-year-old child with tumor thrombus extending into the right atrium.

Successful management of Wilms tumor accompanied by traumatic renal injury: a case report

When a tumor and trauma coexist, the treatment strategy must be established while considering their interaction. We herein report a 5-month-old girl with Wilms tumor complicated by blunt renal trauma. She was involved in a traffic accident and had hemorrhagic shock due to renal bleeding. We performed hemostasis by transcatheter arterial embolization. Ten days later, we extirpated the potential malignant tumor and left kidney. We were able to complete the surgery without rupture or major bleeding. Postoperative histopathology confirmed Wilms tumor. In the year since she received postoperative chemotherapy, there has been no recurrence. When we were deciding the treatment strategy, we first had to determine how much the renal trauma had affected the tumor staging. The second issue was when to extirpate the tumor after managing the trauma. There are no standard criteria for such situations at present, so we referred to the criteria concerning the bed rest period in cases of traumatic kidney injury and previous case reports and decided to wait over a week from the injury treatment to perform surgery. As a result, we were able to remove the tumor completely without any rupture or major bleeding.

Differentiation between Clear Cell Sarcoma of the Kidney and Wilms' Tumor with CT

Objective

Clear cell sarcoma of the kidney (CCSK) is the second-most common but extremely rare primary renal malignancy in children after Wilms' tumor. The aims of this study were to evaluate the imaging features that could distinguish between CCSK and Wilms' tumor and to assess the features with diagnostic value for identifying CCSK.

Materials and Methods

We reviewed the initial contrast-enhanced abdominal-pelvic CT scans of children with CCSK and Wilms' tumor between 2010 to 2019. Fifty-eight children (32 males and 26 females; age, 0.3–10 years), 7 with CCSK, and 51 with Wilms' tumor, were included. The maximum tumor diameter, presence of engorged perinephric vessels, maximum density of the tumor (Tmax) of the enhancing solid portion, paraspinal muscle, contralateral renal vein density, and density ratios (Tmax/muscle and Tmax/vein) were analyzed on the renal parenchymal phase of contrast-enhanced CT. Fisher's exact tests and Mann-Whitney U tests were conducted to analyze the categorical and continuous variables, respectively. Logistic regression and receiver operating characteristic curve analyses were also performed.

Results

The age, sex, and tumor diameter did not differ between the two groups. Engorged perinephric vessels were more common in patients in the CCSK group (71% [5/7] vs. 16% [8/51], p = 0.005). Tmax (median, 148.0 vs. 111.0 Hounsfield unit, p = 0.004), Tmax/muscle (median, 2.64 vs. 1.67, p = 0.002), and Tmax/vein (median, 0.94 vs. 0.59, p = 0.002) were higher in the CCSK compared to the Wilms' group. Multiple logistic regression revealed that engorged vessels (odds ratio 13.615; 95% confidence interval [CI], 1.770–104.730) and Tmax/muscle (odds ratio 5.881; 95% CI, 1.337–25.871) were significant predictors of CCSK. The cutoff values of Tmax/muscle (86% sensitivity, 77% specificity) and Tmax/vein (71% sensitivity, 86% specificity) for the diagnosis of CCSK were 1.97 and 0.76, respectively.

Conclusion

Perinephric vessel engorgement and greater tumor enhancement (Tmax/muscle > 1.97 or Tmax/vein > 0.76) are helpful for differentiating between CCSK and Wilms' tumor in children aged below 10 years.

Retrospective analysis of outcomes in patients with clear cell sarcoma of the kidney: A tertiary single-institution experience

BACKGROUND

Clear cell sarcoma of the kidney (CCSK) is a rare and aggressive tumor. This study aims to describe the clinical characteristics and outcomes of CCSK patients in one of the largest pediatric medical centers in China.

METHODS

We included all patients diagnosed with CCSK between January 2008 and March 2019 at the Children's Hospital of Chongqing Medical University, China. The patients' demographics, clinical presentation, and management were reviewed. Follow-up was continued until December 2019.

RESULTS

In total, 41 CCSK patients (66% male) with a median age of 24 months (range 3-108 months) were identified. The stage distributions of stages I, II, III and IV were 42%, 34%, 24% and 0%, respectively. Preoperative chemotherapy was administered to 7/41 patients. All patients underwent radical nephrectomy and postoperative chemotherapy. The median number of lymph nodes sampled was 4 (range 1-12). Radiotherapy was applied in 8/41 patients. The 5-year event-free survival (EFS) and overall survival (OS) were 63.9% and 78.8%, respectively. Of the 41 patients, 11 patients experienced relapse at a median time of 19 months (range 5-72 months). The most common site of recurrence was the tumor bed (9/11). Young age was a significant adverse prognostic factor for EFS.

CONCLUSIONS

The overall outcome of CCSK patients in our hospital is poorer than that in developed regions. More research is needed to clarify the underlying causes of poorer outcomes in young patients and improve outcomes.

TYPE OF STUDY

Retrospective study.

LEVEL OF EVIDENCE

LEVEL IV.

Renal leiomyoma: An uncommon differential diagnosis of renal masses in pediatric age

Leiomyoma is a mesenchymal tumor which arise from any structure or organ containing smooth muscle, but is frequently seen in the female genital tract. Renal leiomyoma is extremely rare benign lesion with low incidence (1:1000), has been reported mostly in adults and very few cases have been described in the pediatric age-group. It is often asymptomatic and can be diagnosed when reaches large sizes. Hereby, we present a case of renal leiomyoma in a smaller size, in the pediatric age group.

Is adrenalectomy necessary during unilateral nephrectomy for Wilms Tumor? A report from the Children's Oncology Group

PURPOSE

To determine whether performing adrenalectomy at the time of nephrectomy for unilateral Wilms tumor impacts clinical outcome.

METHODS

We reviewed information on all patients enrolled on National Wilms Tumor Study-4 and -5. Data were abstracted on patient demographics, tumor characteristics, surgical and pathologic status of the adrenal gland, and patient outcomes. The primary endpoints were intraoperative spill and five-year event-free survival (EFS) in patients who did or did not undergo adrenalectomy.

RESULTS

Of 3825 patients with complete evaluable data, the adrenal was left in situ in 2264 (57.9%) patients, and was removed completely in 1367 patients (36.7%) or partially in 194 patients (5.2%). Of the adrenal glands removed, 68 (4.4%) contained tumor. Adrenal involvement was more common in patients with stage 3 (9.8%) than stage 2 disease (1.9%; p < 0.0001). After controlling for stage and histopathology, five-year EFS was similar whether or not the adrenal gland was removed (p = 0.48), or involved with tumor (p = 0.81); however, intraoperative spill rates were higher in patients undergoing adrenalectomy (26.1% vs 15.5%, p < 0.0001), likely due to larger tumor size or technical factors. No patient had clinical evidence of adrenal insufficiency or tumor recurrence in the adrenal gland during follow-up (median 9.9 years).

CONCLUSIONS

Sparing the adrenal gland during nephrectomy for unilateral Wilms tumor was not associated with a higher incidence of intraoperative spill and was associated with a similar oncologic outcome, on a per-stage basis, with cases where the adrenal was removed. Thus, adrenalectomy should not be considered mandatory during radical nephrectomy for Wilms tumor.