Pediatric renal cell carcinoma: single institution 25-year case series and initial experience with partial nephrectomy

A population-based study on incidence trends of kidney and renal pelvis cancers in the United States over 2000-2020

Cancers of the kidney and renal pelvis are among the most prevalent types of urinary cancers. We aimed to outline the incidence trends of kidney and renal pelvis cancers by age, sex, race/ethnicity, and histology in the United States (US) from 2000 to 2020. The data was obtained from the Surveillance, Epidemiology, and End Results (SEER) 22 database. The identification of patients with kidney and renal pelvis cancers with morphologies of renal cell carcinoma, nephroblastoma, sarcoma, and neuroendocrine tumor was conducted utilizing the International Classification of Diseases for Oncology version 3. The average annual percent change (AAPC) were presented. All estimates were given in the form of counts and delayed age-standardized incidence rates (ASIRs) per 100,000 people. From 2000 to 2019, a total of 490,481 cases of kidney and renal pelvic cancer were recorded across all age groups in the US. The majority of them were among Non-Hispanic Whites (NHWs) (69.75%) and those aged 55-69 years (39.96%). The ASIRs per 100,000 for kidney and pelvis cancers were 22.03 for men and 11.14 for women. Non-Hispanic Black men had the highest ASIR (24.53 [24.24, 24.81]), and increase in ASIR over the 2000-2019 period (AAPC: 2.19% [1.84, 2.84]). There was a noticeable increase in incidence of kidney and renal pelvis cancers. Individuals aged 70-84 years had the highest ASIR for kidney and renal pelvis cancers. The COVID-19 era has resulted in a significant reduction in incidence rates across all demographics.

Nephron-sparing surgery for renal cell carcinoma in children and young adults: A systematic review

OBJECTIVE

To determine the patient characteristics and role of nephron-sparing surgery (NSS) in the treatment of children and young adults with renal cell carcinoma (RCC).

METHODS

A systematic search of Embase, MEDLINE, and Scopus databases was conducted in December 2021 according to Cochrane collaboration recommendations. All included manuscripts were assessed for patient characteristics and all reported outcomes for patients undergoing partial nephrectomy (PN), and radical nephrectomy (RN) outcomes were abstracted as a comparison group. Primary outcomes included surgical outcomes, overall survival, kidney outcomes. Outcomes were pooled with weighted mean and ranges. Meta-analysis was not performed given study quality. This systematic review was prospectively registered on PROSPERO (CRD42022300261).

RESULTS

We found a total of 16 studies describing 119 and 559 unique patients undergoing PN and RN, respectively, with a mean age of 12.2 years and mean follow-up of 59.1 months. The mean tumor size for patients undergoing PN was 3.5 cm. Of the 113 patients undergoing PN with available data, 109 were alive at follow-up (98%). No studies reported long-term kidney outcomes, and four studies reported surgical outcomes. All studies had at least moderate risk of bias.

CONCLUSIONS

The use of NSS in children and young adults with RCC is feasible in selected patients. However, small sample sizes, confounding, and low study quality limit clinical recommendation on NSS in this population. There are significant opportunities for future research on the use of NSS in RCC, especially with systematic reporting of oncological, kidney, and surgical outcomes.

Unusual Renal Mass in a Pediatric Patient

Renal cell carcinoma (RCC) is rare in the pediatric population, comprising about 5% of renal neoplasms in children.¹ Out of all childhood cases of RCC, translocation RCCs (tRCC) is the most common.² It is well described in the literature that exposure to alkylating agents such as cyclophosphamide and/or topoisomerase II inhibitors such as doxorubicin and etoposide, is a risk factor for the development of Xp11 (or TFE3) tRCC.³ Herein is a case of tRCC development in a patient with history of exposure to topoisomerase II inhibitors and alkylating agents to treat a common childhood malignancy.

Non-Wilms' renal tumors in children: experience with 139 cases treated at a single center

Background

Pediatric non-Wilms renal tumors (NWRTs), which comprise a small proportion of renal tumors, are a heterogeneous group of neoplasms with variable malignant potential, mortality, and response to treatment. We performed this study to determine the clinical characteristics, management and prognosis of children with Pediatric NWRTs.

Methods

Medical records of all patients (n = 139) treated for NWRTs over a 12-year period (2008.01–2019.10) at a single center were reviewed retrospectively.

Results

The histopathological groups of NWRTs included malignant rhabdoid tumor of the kidney (MRTK) (n: 30, 21.6%), renal cell cancer (RCC) (n: 26,18.7%), clear cell sarcoma of the kidney (CCSK) (n: 24,17.3%), congenital mesoblastic nephroma (CMN) (n: 21,15.1%), cystic nephroma (CN) (n: 16,11.5%), metanephric tumors (n: 12, 8.6%), renal angiomyoliporma (RAML) (n: 3, 2.2%), renal primitive neuroectodermal tumor (n: 2, 1.4%), renal hemangioma (n: 2, 1.4%), inflammatory myofibroblastic tumor (n: 2, 1.4%), ossifying renal tumor of infancy (ORTI) (n: 1, 0.7%). The distribution of all malignant NWRTs, including MRTK, CCSK, RCC and PNET, according to stage was as follows: stages I (n = 26), II (n = 16), III (n = 29), and IV (n = 11). The summary table shows the treatment offered to children with NWRTs. A total of 123 children were followed up for an average of 42 months. Sixteen children were lost to follow-up. Tumor-free survival was observed in 94 children. One patient who suffered from RCC is currently receiving targeted therapy and survives with the tumor. Twenty-eight children (22.8%) died.

Conclusions

Pediatric NWRTs comprise 19.1% of all renal tumors in our single center. Most NWRTs can readily be distinguished using a range of immunohistochemical markers. Molecular genetic profiling has allowed much progress in the understanding of this group of tumors, making diagnosis and classification less difficult. The mainstay treatment of malignant NWRTs, including MRTK, CCSK, RCC and PNET, is comprehensive treatment. The mainstay treatment of benign NWRTs, including RAML, CN, ORTI, CMN, metanephric tumors, and renal hemangioma, is surgical resection alone and when the tumor diameter is smaller than 7 cm and the tumor locates in one pole, NSS can be performed.

Renal cell carcinoma in children and adolescents: A retrospective study of a French-Italian series of 93 cases

BACKGROUND

Renal cell carcinomas represent 2 to 5% of kidney malignancies in children and adolescents. Appropriate diagnostic and classification are crucial for the correct management of the patients and in order to avoid inappropriate preoperative chemotherapy, which is usually recommended if a Wilms tumor is suspected.

METHODS

a French-Italian series of 93 renal cell carcinomas collected from 1990 to 2019 in patients aged less than 18 years old was reclassified according to the 2016 WHO classification and the latest literature. TFE3 and TFEB FISH analyses and a panel of immunohistochemical stains were applied.

RESULTS

The median age at diagnosis was 11 years (range: 9 months - 17 years). MiT family (MiTF) translocation renal cell carcinomas accounted for 52% of the tumors, followed by papillary renal cell carcinomas (20%) and unclassified renal cell carcinomas (13%). Other subtypes, such as SDHB-deficient and Fumarate hydratase-deficient renal cell carcinomas, represented 1 to 3% of the cases. We also described a case of ALK-rearranged renal cell carcinoma with a metanephric adenoma-like morphology.

CONCLUSION

A precise histological diagnosis is mandatory as targeted therapy could be applied for some RCC subtypes, i.e., MiTF-translocation and ALK-translocation renal cell carcinomas. Moreover, some RCC subtypes may be associated with a predisposition syndrome that will impact patients' and family's management and genetic counseling. A precise RCC subtype is also mandatory for the clinical management of the patients and the inclusion in new prospective clinical trials.

Characteristics and outcome of pediatric renal cell carcinoma patients registered in the International Society of Pediatric Oncology (SIOP) 93-01, 2001 and UK-IMPORT database: A report of the SIOP-Renal Tumor Study Group

In children, renal cell carcinoma (RCC) is rare. This study is the first report of pediatric patients with RCC registered by the International Society of Pediatric Oncology-Renal Tumor Study Group (SIOP-RTSG). Pediatric patients with histologically confirmed RCC, registered in SIOP 93-01, 2001 and UK-IMPORT databases, were included. Event-free survival (EFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Between 1993 and 2019, 122 pediatric patients with RCC were registered. Available detailed data (n = 111) revealed 56 localized, 30 regionally advanced, 25 metastatic and no bilateral cases. Histological classification according to World Health Organization 2004, including immunohistochemical and molecular testing for transcription factor E3 (TFE3) and/or EB (TFEB) translocation, was available for 65/122 patients. In this group, the most common histological subtypes were translocation type RCC (MiT-RCC) (36/64, 56.3%), papillary type (19/64, 29.7%) and clear cell type (4/64, 6.3%). One histological subtype was not reported. In the remaining 57 patients, translocation testing could not be performed, or TFE-cytogenetics and/or immunohistochemistry results were missing. In this group, the most common RCC histological subtypes were papillary type (21/47, 44.7%) and clear cell type (11/47, 23.4%). Ten histological subtypes were not reported. Estimated 5-year (5y) EFS and 5y OS of the total group was 70.5% (95% CI = 61.7%-80.6%) and 84.5% (95% CI = 77.5%-92.2%), respectively. Estimated 5y OS for localized, regionally advanced, and metastatic disease was 96.8%, 92.3%, and 45.6%, respectively. In conclusion, the registered pediatric patients with RCC showed a reasonable outcome. Survival was substantially lower for patients with metastatic disease. This descriptive study stresses the importance of full, prospective registration including TFE-testing.

Association of beta-catenin and CD44 in the development of renal cell carcinoma

INTRODUCTION AND OBJECTIVE

Renal cell carcinoma (RCC) accounts for approximately 3% of all cancers. Approximately 25%-30% of patients present with metastatic disease at the time of diagnosis, and metastatic RCC is a treatment-resistant malignancy. Altered expression of cell adhesion molecules such as CD44 on tumor cells suggests a pathogenetic mechanism for tumor metastasis and may provide prognostic information for particular tumors. These cell matrix interactions of CD44 play a role in tumor cell invasion and metastasis. The Wnt/beta-catenin pathway turned out to be a promising target as it is involved in the regulation of cell proliferation, differentiation and apoptosis induction.

METHOD

In this study, the expression of beta-catenin and CD44 was analyzed in primary renal cell carcinoma (RCC) samples to understand their association with development of the disease. For this purpose, immunohistochemical expression analysis of beta-catenin and CD44 was performed in 30 primary RCC histological samples and normal kidney tissues in different subtypes at different clinical stages of Indian patients (year: 2017-2019).

RESULT

Most of the patients who presented were diagnosed as clear cell carcinoma and it was observed that expression of CD44 was high in patients with high stage tumors. Also beta-catenin was increased in advanced grade tumors, but there was insignificant correlation between high expression of molecules and survival or recurrence of disease.

CONCLUSION

Both cd44 and beta-catenin activation was noted in patients with clear cell carcinoma, more in advanced tumors. Both can be promising targets for treatment in clear cell RCCs.

Pediatric and young adult renal cell carcinoma

Renal cell carcinoma (RCC) is rare in children but is the most common renal tumor in adults. Pediatric RCC has different clinical characteristics, histopathology, and treatment compared with adult disease. Databases were reviewed from inception to February 2020, identifying 32 publications pertaining to 350 patients under 27 years. Surgery is the cornerstone for cure in localized RCC. Lymph node dissection remains controversial. Conventional radiotherapy has no curative role in RCC; similarly, conventional chemotherapy has not proven to be effective in large cohorts. Pediatric metastatic RCC has a poor outlook. There are no published prospective studies demonstrating which adjuvant therapy could improve outcome. Sunitinib, a tyrosine kinase inhibitor, is recommended in this group despite limited evidence. This review provides an overview for pediatric RCC, including the evolving role of precision medicine.

Secondary renal neoplasia following chemotherapy or radiation in pediatric patients

Renal neoplasia occurring as a second malignancy following childhood cancer has been most closely associated with neuroblastoma and Wilms tumor. While some cases have been associated with a genetic predisposition, nearly all are thought to result from "late effects" of therapy-related toxicity that involves chemotherapy or radiation. It is unclear if these tumors are enriched for specific molecular or morphologic characteristics. A query of our institutional nephrectomy registry of 8295 patients for renal neoplasia occurring post-treatment for childhood cancer revealed 6 patients with Wilms tumor, 4 with neuroblastoma, and 1 with acute lymphoblastic leukemia (ALL). Three additional cases of MiT family translocation renal cell carcinoma (RCC), from 2 patients, following chemotherapy for neuroblastoma and systemic lupus erythematosus and another of clear cell RCC post-ALL were included. The most common tumor type was clear cell RCC: 9/19 cases (47.4%), followed by metanephric adenoma and MiT family translocation RCC (3/19, 15.8%). There were no characteristic features to indicate a unique renal neoplasia subtype. Potential syndromic renal neoplasia occurred in 2 patients, metanephric adenomas and oncocytoma in a patient with hyperparathyroidism-jaw tumor syndrome post-treatment of Wilms tumor and a fumarate hydratase-deficient RCC in a patient post-treatment for ALL. The mean age at diagnosis of childhood neoplasia or treatment with chemotherapy or radiation was 4.7 years, and the average time to subsequent renal neoplasia was 31 years. Five (of 14) patients developed metastatic RCC, and there were 2 RCC-related deaths. These results indicate the need for extended clinical follow-up of these patients.

Characteristics and Outcome of Children with Renal Cell Carcinoma: A Narrative Review

Pediatric renal cell carcinoma (RCC) is a rare type of kidney cancer, most commonly occurring in teenagers and young adolescents. Few relatively large series of pediatric RCC have been reported. Knowledge of clinical characteristics, outcome and treatment strategies are often based on the more frequently occurring adult types of RCC. However, published pediatric data suggest that clinical, molecular and histological characteristics of pediatric RCC differ from adult RCC. This paper summarizes reported series consisting of ≥10 RCC pediatric patients in order to create an up-to-date overview of the clinical and histopathological characteristics, treatment and outcome of pediatric RCC patients.

Pediatric renal cell carcinoma

PURPOSE OF REVIEW

To review the presentation, natural history and treatment of renal cell carcinoma in children and young adults with renal cell carcinoma (RCC).

RECENT FINDINGS

Complete resection of lymph nodes at the time of tumor resection can improve clinical outcomes and limit the need for adjuvant chemotherapy. Genetic alterations that lead to translocation tumors are a therapeutic target of receptor tyrosine kinase inhibitors.

SUMMARY

The incidence of RCC increases with age. Unlike adult patients, young patients with RCC present symptomatically and at higher stage and grade. Translocation tumors predominate RCC in children with biologic activity characterized by early spread to lymph nodes with small primary tumors. Preoperative imaging is poorly sensitive for positive lymph nodes; as such, surgeons should have a low threshold for lymph node sampling during tumor resection. Despite the advanced stage at presentation, the prognosis in children is more favorable than their adult counterparts. Complete resection of lymph nodes at the time of surgical resection improves patient prognosis. Chemotherapy targeting the PI3/AKT pathway has demonstrated clinical benefit.

Comparative study of renal cell carcinoma in patients less than 40 years of age and older age patients: A retrospective single-center study

BACKGROUND

Renal cell carcinoma (RCC) is typically found in the older age group between 50 and 70 years of age. However, diagnosis of renal cancer is increasing more rapidly in patients less than 40 years if age compared to older age patients.

AIMS AND OBJECTIVES

To compare the clinicopathological spectrum and survival in patients with RCC in relation to age in a tertiary care hospital in eastern India.

STUDY DESIGN

Retrospective cohort study.

MATERIALS AND METHODS

Patients operated between February 2008 and January 2017 for renal masses having clinical and radiological suspicion and histopathologically proven RCC were analyzed from hospital records. Clinicopathological data and survival study were compared between patients less than 40 years of age and older age patients. STATISTICAL ANALYSIS USED: Statistical and survival analysis was done using Statistical Package for the Social Sciences 20.

RESULTS

Among 198 patients, 36 (18.2%) patients less than 40 years were diagnosed with RCC and 162 in older patients. In these 36 younger patients, 17 (47.2%) were male and 19 (52.7%) were female. A total of 63.8% in younger age group and 69.1% of older patients were diagnosed with stage 1 and 2 RCC; comparing younger to older patients, younger patients had high number of papillary carcinoma (22.2% vs. 11.7%, P = 0.096). Younger patients have shown marginally better 5-year overall survival and disease-free survival (P > 0.05).

CONCLUSION

Our study concludes that younger age patients were more affected by RCC specially papillary RCC, when compared to western population. In addition females had more incidence of RCC. Prognosis was similar in both groups.

Nephron-sparing surgery in the treatment of pediatric renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusions

PURPOSE

To investigate the safety and efficacy of nephron-sparing surgery (NSS) in the treatment of pediatric Xp11.2 translocation renal cell carcinoma (RCC).

METHODS

Clinical characteristics of 9 RCC children (7 males and 2 females) with Xp11.2 translocation who received NSS between January 1973 and December 2015 were retrospectively analyzed. The mean age was 7.8years (range: 4.5-13.5years). Xp11.2 translocation RCC was found in the left side in 4 patients and right in 5. 3 tumors were located in the upper pole of the kidney, 1 in the middle dorsal, 1 in the middle ventral and 4 in the lower pole. RCC presented with painless gross hematuria in 4 patients, abdominal mass in 1, and as an incidental finding by ultrasound examination in 4 patients. The mean course of hematuria was 3months (range: 1-7months). The mean tumor diameters were 3.7cm (range: 2.2-6.9cm).

RESULTS

All the patients received NSS with open transperitoneal approach. The mean operative time and estimated blood loss were 115min and 40ml, respectively. The time of renal pedicle clamping was 19-25min (mean: 21.5min). No complications (such as leakage of urine, prolonged drainage or secondary bleeding) were noted. No patients experienced local recurrence during the mean of 50.1-month follow-up (range: 13-117months). Intravenous urography (IVU) or contrast-enhanced CT was conducted at 6months after surgery which showed favorable kidney function in all patients.

CONCLUSION

Xp11.2 translocation RCC is a predominant pathological but biologically inert type of pediatric RCC. For Xp11.2 translocation RCC sized <4-7cm in diameter and located in one pole, NSS is safe and feasible.

TYPE OF STUDY

Treatment Studies, LEVEL IV.

Renal Cell Carcinoma Occurring in Patients With Prior Neuroblastoma: A Heterogenous Group of Neoplasms

Renal cell carcinoma (RCC) associated with neuroblastoma (NB) was included as a distinct entity in the 2004 World Health Organization classification of kidney tumors. A spectrum of RCC subtypes has been reported in NB survivors. We herein describe a series of 8 RCCs diagnosed in 7 patients with a history of NB. Microscopic evaluation, immunohistochemical staining for PAX8, cathepsin K, and succinate dehydrogenase subunit B (SDHB), and fluorescence in situ hybridization (FISH) for TFE3 and TFEB were performed. Four distinct morphologic subtypes were identified: 3 tumors were characterized by cells with abundant oncocytoid cytoplasm and irregular nuclei; 3 showed features of microphthalmia transcription factor family translocation RCC (MiTF-RCC); 1 had features of hybrid oncocytic-chromophobe tumor; 1 had papillary RCC histology. All RCCs expressed PAX8 and retained SDHB expression. Cathepsin K was positive in 2 MiTF-RCCs, 1 was TFEB FISH positive, and the other was indeterminate. Cathepsin K was negative in a third MiTF-RCC with TFE3 rearrangement. TFE3 FISH was negative in 4 and insufficient in 1 of the other 5 RCCs. While a subset of RCCs associated with NB is characterized by cells with prominent oncocytoid cytoplasm, other RCC subtypes also occur in post-NB patients. Renal neoplasms occurring in patients with a history of NB do not represent a single entity but a heterogenous group of RCCs. SDHB mutations do not explain the subset of nontranslocation RCCs with oncocytoid features; therefore, further studies are needed to clarify whether they may represent a distinct entity with unique molecular abnormalities or may belong to other emerging RCC subtypes.

[Renal cell carcinomas in childhood]

BACKGROUND

Renal cell carcinoma is a rare childhood disease. However, it should be considered in the differential diagnosis in the detection of a renal mass.

OBJECTIVES

Incidence and mortality of renal cell carcinomas in childhood. Presentation of clinical symptoms, diagnostics, histology, therapy and course of the disease.

PATIENTS AND METHODS

Evaluation of our own prospective data of a small patient population of 8 patients, as well as discussion of the current literature on this tumor entity.

RESULTS

The average follow-up period was 27 months. Preoperative staging studies showed no metastases. The histologically primary predominant subtype was papillary renal cell carcinoma. Tumor stage and lymph node status were the most important prognostic factors in our study.

CONCLUSIONS

Renal cell carcinoma in childhood is a rare disease whose treatment is challenging and should be performed in an interdisciplinary team. Typical clinical symptoms, as in adults, are absent. The partial nephrectomy should be, if practicable, the surgical treatment of choice. The most important risk factors for survival are tumor stage and lymph node status. Data on adjuvant target therapy for metastatic disease in childhood are lacking. Further prospective, multicenter studies are necessary to generate more information on the biology and course of this disease and to obtain adjuvant treatment options in locally advanced disease.

Distinguishing pediatric and adolescent renal cell carcinoma from other renal malignancies

PURPOSE

Renal cell carcinoma (RCC) represents a small proportion of renal malignancies early in life. Distinguishing RCC from other malignancies is important as treatment strategies may differ. We analyze the Surveillance Epidemiology, and End Results (SEER) database to identify predictive factors of RCC in the pediatric population with renal tumors.

METHODS

We queried SEER to identify patients from ages 0 to 19 diagnosed with a renal malignancy between 1973 and 2013. Cases were sorted using histology and site codes. Age-adjusted standardized incidence rates (SIR) were calculated. We compared differences in characteristics between cancer types. A logistic regression model and a nomogram were created to identify predictors of RCC.

RESULTS

A total of 3,670 patients were identified, of which 281 (7.7%) were diagnosed with RCC. The SIR of RCC increased with age. After age 12, RCC was found in >50% of all newly diagnosed cases. On multivariate analysis, RCC was associated with smaller tumor size (P < 0.001), increasing age (P < 0.001), black race (P < 0.001), and localized stage (P < 0.001). The nomogram predicted RCC pathology with a concordance index of 0.965.

CONCLUSIONS

RCC in childhood and adolescence is relatively uncommon; however, it accounts for >50% of renal malignancies after age 12. For every year of increasing age, the odds of having an RCC diagnosis are increased by 50%. The odds of a renal tumor being RCC are increased in black children, those with localized disease, and those with smaller tumors. In these specific populations, RCC should be favored in the differential diagnosis of the renal mass.

Renal Cancer in Recipients of Kidney Transplant

The aim of our study is to determine characteristics and outcomes of kidney cancer in renal transplant recipients. MEDLINE® database was searched in June 2015 to identify cases of kidney cancer in renal transplant recipients. We include also a new case. Descriptive statistics were used for analysis. Forty-eight (48) recipients reported in 25 papers met the eligibility criteria. The median age was 47 years (range 9-66); 27% were females. Chronic glomerulonephritis, cystic kidney disease and hypertension were common indications for renal transplant. Among donors 24% were females and the median age was 52.5 years (17-73); 62% of kidney cancers were donor-derived. The median interval between transplant and cancer diagnosis was shorter for cancer of recipient versus donor origin (150 vs. 210 days). Clear cell carcinoma was diagnosed in 17%. 25% had metastasis at diagnosis. Kidney explantation or excision was done in 90% and 84% of cases with and without metastasis respectively. The median survival was 72 months. Actuarial 1-year and 5-year survival rates were 73.4% and 55.1% respectively. Among the recipients from 7 donors who subsequently developed malignancy, 57% were dead within a year. Kidney transplant recipients have a small risk of kidney cancer, which affects younger patients and occurs within a year of transplant, likely due to immunosuppression. Whether the use of older donors may increase the likelihood needs further investigation. The presence of metastasis, explantation or excision of affected kidney and development of cancer in donors predict outcomes. The results may guide patient education and informed decision-making.

Kaempferol Inhibits the Invasion and Migration of Renal Cancer Cells through the Downregulation of AKT and FAK Pathways

Kaempferol, which is isolated from several natural plants, is a polyphenol belonging to the subgroup of flavonoids. Kaempferol exhibits various pharmacological activities, including anti-inflammatory, antioxidant, antimicrobial, and anticancer activities. In this study, kaempferol can significantly inhibit the invasion and migration of 786-O renal cell carcinoma (RCC) without cytotoxicity. We examined the potential mechanisms underlying its anti-invasive activities on 786-O RCC cells. Western blot was performed, and the results showed that kaempferol attenuates the manifestation of metalloproteinase-2 (MMP-2) protein and activity. The inhibitive effect of kaempferol on MMP-2 may be attributed to the downregulation of phosphorylation of Akt and focal adhesion kinase (FAK). By examining the SCID mice model, we found that kaempferol can safely inhibit the metastasis of the 786-O RCC cells into the lungs by about 87.4% as compared to vehicle treated control animals. In addition, the lung tumor masses of mice pretreated with 2-10 mg/kg kaempferol were reduced about twofold to fourfold. These data suggested that kaempferol can play a promising role in tumor prevention and cancer metastasis inhibition.

Metastatic clear cell variant of renal cell carcinoma of the mandible: Review and case report

A case of metastatic renal cell carcinoma (RCC) to the mandible is reported. A 22-year-old man consulted us for hypoesthesia of the right lower lip. Panorama X-ray film showed a radiolucent lesion in the right mandibular body. A diagnosis of a metastatic tumor to the mandible from the right kidney was made after evaluation by computed tomography and bone scan with Tc99 methyl diphosphonate which also revealed multiple bone metastases. Histologically diagnosis was clear cell variant of RCC. Patient has been put on radiotherapy for symptomatic treatment and a molecularly targeted drug. The therapy effectively stopped the progressive growth of oral and other metastatic lesions. The quality of life is relatively well maintained with tolerable adverse effects. The patient is still on our follow-up with an improved quality of life.

Factors impacting survival in children with renal cell carcinoma

PURPOSE

Renal cell carcinoma (RCC) is an uncommon tumor in the pediatric population. We examined a large national cancer database to determine outcomes for children with RCC and to identify variables affecting long-term survival.

METHODS

The National Cancer Data Base (NCDB) was queried for patients age 0 to 17 years diagnosed with RCC from 1998-2011. Patient demographics, tumor stage and characteristics, management, and outcomes were evaluated.

RESULTS

A total of 304 children met inclusion criteria. Overall, 39% of children had stage I disease, 16% stage II, 33% stage III, and 12% stage IV. One-year and five-year survival for all children was 87% and 70%, respectively. Eighty-six percent of patients underwent surgical resection. In comparison to children who underwent complete nephrectomy, patients undergoing partial nephrectomy had smaller tumors and were of lower clinical stages. Survival following partial resection was 100% at one and five years. Age and gender had no significant impact on survival. Survival was negatively impacted by increasing tumor size (P<0.001), positive nodal status (P=0.001), and higher pathologic stage (P<0.001).

CONCLUSION

Children with renal cell carcinoma who undergo surgical resection have excellent one-year and five-year survival. Overall survival is significantly affected by pathologic stage, tumor size, and nodal status.

A case of chromophobe renal cell carcinoma in a 12-year-old girl

Renal cell carcinoma (RCC) accounts for only 2-6 % of pediatric renal tumors. Chromophobe RCC is very rare in pediatric patients, with only a few cases reported. A 12-year-old girl who had abdominal and left flank pain visited the pediatric clinic of a local hospital. A uniformly enhanced tumor measuring 2.5 cm × 2.3 cm was found on computed tomography. On magnetic resonance imaging, T2-weighted images showed a solid tumor with hyperintensity suggesting intratumoral necrosis. We considered RCC and Wilms' tumor as differential diagnoses, but we could not reach a definitive diagnosis from the radiographic findings. We then performed right partial nephrectomy with regional lymph node dissection. The histopathological diagnosis was pT1aN0 chromophobe RCC. After the surgery, no recurrence has been observed for 15 months.

Characterization of adolescent and pediatric renal cell carcinoma: A report from the Children's Oncology Group study AREN03B2

BACKGROUND

The current study was conducted to characterize the epidemiology, histology, and radiographic features of as well as the surgical approach to pediatric and adolescent renal cell carcinoma (pRCC).

METHODS

pRCC cases prospectively enrolled on the Children's Oncology Group study AREN03B2 underwent central pathology, radiology, surgery, and oncology review.

RESULTS

As of June 2012, 120 of a total of 3250 patients enrolled on AREN03B2 (3.7%) were found to have unilateral RCC (median age, 12.9 years [range, 1.9-22.1 years]; 52.5% were female). Central review classified these as translocation morphology (56 patients), papillary (20 patients), renal medullary carcinoma (13 patients), chromophobe (4 patients), oncocytoma (1 patient), conventional clear cell (1 patient), and RCC not otherwise specified (25 patients). Lymph node (LN) involvement (N+) was found in 35 of 73 cases (47.9%) for which LNs were sampled, including 19 of 40 cases with primary tumors measuring <7 cm (47.5%). Using a size cutoff of 1 cm, imaging detection of LN involvement had a sensitivity of 57.14% (20 of 35 cases; 95% CI, 39.35%-73.68%) and a specificity of 94.59% (35 of 37 cases; 95% CI, 81.81%-99.34%). Distant metastases were present in 23 cases (19.2%). Initial surgery was radical nephrectomy in 88 patients (73.3%), nephron-sparing surgery in 18 patients (15.0%), and biopsy in 14 patients (11.7%). Compared with patients undergoing radical nephrectomy, those treated with nephron-sparing surgery were less likely to have LNs sampled (6 of 18 patients [33.3%] vs 65 of 88 patients [73.9%]; P = .002).

CONCLUSIONS

Translocation RCC is the most common form of pediatric and adolescent RCC. Lymph node disease is common and observed among patients with small primary tumors. Imaging has a high specificity but relatively low sensitivity for the detection of such lymph node disease. Failure to sample LNs results in incomplete staging and potentially inadequate disease control for younger patients with RCC.

A rare cause of childhood renal cysts: Xp11.2 translocation renal cell carcinoma

Pediatric renal cysts are rare, usually asymptomatic and incidentally detected in children. Cyst associated renal cell carcinoma (RCC) or cystic RCC is extremely rare in children. Bosniak classification system has been accepted for the management of cystic renal masses. Xp11.2 translocation RCC is a recently classified distinct subtype and usually affects children and adolescents. We report the case of a 10-year-old girl with Xp11.2 translocation RCC from a cyst of the right kidney.

An approach to renal masses in pediatrics

Renal masses in children may be discovered during routine clinical examination or incidentally during the course of diagnostic or therapeutic procedures for other causes. Renal cancers are rare in the pediatric population and include a spectrum of pathologies that may challenge the clinician in choosing the optimal treatment. Correct identification of the lesion may be difficult, and the appropriate surgical procedure is paramount for lesions suspected to be malignant. The purpose of this article is to provide a comprehensive overview regarding the spectrum of renal tumors in the pediatric population, both benign and malignant, and their surgical management.

Renal cell carcinoma in children, adolescents and young adults: a National Cancer Database study

PURPOSE

We compared the presentation and outcomes of patients younger than 21 years with renal cell carcinoma and determined risk factors associated with mortality.

MATERIALS AND METHODS

We searched the National Cancer Database for patients diagnosed with renal cell carcinoma between 1998 and 2011. We evaluated patients younger than 30 years with renal cell carcinoma, including clear cell, chromophobe, papillary and not otherwise specified subcategories. We used logistic regression to compare presenting cancer, demographics and treatment variables in patients 0 to 15 years, 15 to 21 years and 21 to 30 years old. Cox regression analysis was used to determine risk factors for mortality in patients younger than 21.

RESULTS

Of 3,658 patients younger than 30 years included in the study 161 were younger than 15 and 337 were 15 to 21 years old. A higher proportion of younger patients had renal cell carcinoma not otherwise specified and papillary histology compared to those 21 to 30 years (p < 0.001). Younger patients presented with higher stage (p < 0.0001), higher grade (p < 0.0001) and larger tumors (p < 0.0001) than those 21 to 30 years. A higher percentage of younger patients underwent lymph node dissection (p < 0.0001) or chemotherapy as first-line treatment (p < 0.0001) compared to those 21 to 30 years. Cox regression analysis demonstrated that stage 4 presentation, government insurance status, nonchromophobic pathology results and not undergoing surgery as first-line treatment were independently associated with increased mortality in patients younger than 21 years.

CONCLUSIONS

Children and adolescents with renal cell carcinoma present with more advanced disease than those 21 to 30 years old. In patients younger than 21 years mortality was associated with the nonchromophobe histological subtype, stage 4 disease, government insurance and not undergoing surgery as first-line therapy.

Variation in use of nephron-sparing surgery among children with renal tumors

OBJECTIVE

Given the negative long-term effects of renal insufficiency, nephron-sparing surgery (NSS) is increasingly discussed for the treatment of pediatric renal tumors. We sought to examine variation in practice patterns of NSS among children with renal tumors.

MATERIALS AND METHODS

We performed a retrospective cohort analysis of claims data for pediatric inpatient admissions captured by the Kids Inpatient Database (1997-2009). We identified children with renal tumors who underwent surgery, including radical nephrectomy (RN) and NSS. We used multivariable logistic regression to assess the relationship between use of NSS and various clinical, demographic, and geographic predictors of interest.

RESULTS

We identified 10,108 pediatric inpatient admissions for renal tumors. Of these, 1657 were surgical admissions, with 1501 patients (90.5%) undergoing RN and 156 (9.5%) undergoing NSS. On multivariable analysis, NSS was associated only with a concomitant diagnosis of renal insufficiency (relative ratio [RR] 3.37, p = 0.01) and surgery in the Northeastern USA (RR 3.07, p = 0.03). Race/ethnicity, age, payer type, procedure year, and other non-clinical factors were not significantly associated with NSS.

CONCLUSION

In a large, nationwide pediatric cohort, RN remains the most common surgical intervention for renal tumors. NSS is significantly associated with a diagnosis of renal insufficiency, but not non-clinical factors such as patient gender or race. © 2014 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.

Pediatric genitourinary oncology

Tumors of the kidney, bladder, prostate, testis, and adrenal represent a large part of the adult urologic practice, but are relatively infrequent in children. The natural history and management of these tumors in the pediatric age is different from that of the adults. As result of the successful work of several clinical trial groups in recent decades, there has been a significant improvement in their cure rates. The aim of this article is to review their most significant clinical aspects, as well as to present an update in their management.

Can Initial (18)F-FDG PET-CT Imaging Give Information on Metastasis in Patients with Primary Renal Cell Carcinoma?

Purpose

The aim of this study was to investigate the relationship between the maximum standardized uptake values (SUVmax) of primary renal cancers with and without metastatic lesions, if any. We also studied the relationship between the size of primary renal cancers and their SUVmax, and tried to find a clinical value of ¹⁸F-FDG PET-CT for the initial evaluation of renal cell carcinoma (RCC).

Methods

The cases of 23 patients, 16 men and 7 women, who underwent PET-CT examination before operation were retrospectively reviewed. We measured the SUVmax of the primary renal cancers and those of any existing metastatic lesions, and the size of the primary renal cancers. We compared the SUVmax of primary RCCs with metastases and those without metastases, SUVmax of primary RCC and those of metastases, and studied the correlation between the size and SUVmax of primary RCCs.

Results

The SUVmax of primary RCC of the 16 patients without metastasis ranged from 1.1 to 5.6 with a median value of 2.6. Those of the patients with metastasis ranged from 2.9 to 7.6 with a median of 5.0. The size of the all 23 primary renal cancers ranged from 1.7 cm to 13.5 cm, with a median of 4.5 cm, and their SUVmax ranged from 1.1 to 7.6, with a median of 2.9. There was a statistically significant difference between the SUVmax of the primary RCC with metastasis (5.3 ± 1.7) and those without metastasis (2.9 ± 1.0). There was a moderate positive correlation between the sizes and SUVmax of all 23 primary RCCs. However, there was no statistically significant correlation between the sizes and SUVmax of primary RCCs with metastatic lesions and the same for RCCs without metastasis. The cutoff value of SUVmax for predicting extra-renal lesion was 4.4 and that for size was 5.8 cm according to the receiver operating characteristic curves.

Conclusions

Those who have primary RCC with high SUVmax are suggested to have a likelihood of metastasis. Also, there was a moderate trend of increasing value of SUVmax of primary RCC as their size increases. Physicians should beware of missing extra-renal lesions elsewhere.

Clear cell, papillary and chromophobe renal cell carcinoma in patients younger than 20 years old: a clinicopathologic study with follow-up

OBJECTIVE

To perform a clinicopathologic study with follow-up on this rare subset of tumors in the pediatric population.

PATIENTS AND METHODS

A search was made through the surgical pathology files of two academic institutions for cases of non-translocation associated renal cell carcinoma in patients younger than 20 years old from 1995 to 2011.

RESULTS

12 cases were identified from 350 pediatric patients with renal tumors (prevalence = 3.4%). The mean age at diagnosis was 11 years (range 1-18 years). The average tumor size was 7.3 cm (range 3.0-15.0 cm). Pathological staging analysis revealed 7/12 (58%) pT1 tumors, 3/12 (25%) pT2 tumors, and 2/12 (17%) pT3 tumors. Lymph node metastasis was present in 3/12 (25%) patients. The majority of tumors 9/12 (75%) were Fuhrman nuclear grade 2, while 3/12 (25%) cases were Fuhrman nuclear grade 3. Tumor necrosis was identified in 5/12 (42%) tumors, and angiolymphatic invasion was identified in 4/12 (33%) tumors; 1 patient developed lung metastasis.

CONCLUSIONS

Pathologic parameters typically associated with poor outcome in adults, including metastasis/high tumor stage, high Fuhrman nuclear grade, angiolymphatic invasion, and tumor necrosis, did not lead to death in any of the patients in our series.

A robotic-assisted laparoscopic approach for pediatric renal cell carcinoma allows for both nephron-sparing surgery and extended lymph node dissection

Partial nephrectomy has been previously reported as safe and effective in appropriately selected children with renal cell carcinoma (RCC). However, there are limited reports of laparoscopic or robotic partial nephrectomy for oncologic surgery in children. Additionally, nodal involvement is common in pediatric RCC, and may present even with small primary tumors. Also, it is suggested that lymph node dissection may provide therapeutic benefit. We present a case of pediatric RCC and demonstrate how the risk of nodal involvement may impact the surgical approach. Robotic-assisted laparoscopy can permit excellent exposure for an oncologically-sound resection, in this case a partial nephrectomy, as well as an extended lymph node dissection.

CT and MRI appearances and radiologic staging of pediatric renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is an uncommon but noteworthy primary pediatric renal malignancy. There is a paucity of published data regarding the CT/MRI appearances and accuracy of pretreatment radiologic staging of this form of cancer in children.

OBJECTIVE

To review the various CT/MRI appearances of pediatric RCC and assess the accuracy of pretreatment radiologic staging using these imaging modalities.

MATERIALS AND METHODS

Institutional Departments of Pathology and Radiology records were searched from 1995 through 2010 for children (younger than 18 years of age) with RCC. Available pretreatment contrast-enhanced abdominopelvic CT and MRI examinations were reviewed by two radiologists. Pertinent imaging findings were documented by consensus, and correlation was made between radiologic and surgicopathological TNM staging.

RESULTS

Pretreatment imaging studies from 10 RCCs in nine children (four girls and five boys; mean age 12.9 years) were reviewed. The mean size of the primary tumor was 6.2 cm (range, 1.5-12.6 cm). Ninety percent of RCCs demonstrated heterogeneous postcontrast enhancement. Fifty percent of masses had associated hemorrhage, while 40% contained internal calcification. Regarding TNM staging, N staging was correct for 10 of 10 tumors, while M staging was correct for 10 of 10 tumors. Imaging correctly staged only 4 of 10 tumors with respect to T stage. Radiologic and surgicopathological overall staging were concordant for 8 of 10 tumors.

CONCLUSION

Pediatric RCCs typically present as large, heterogeneous masses, and they commonly hemorrhage and contain internal calcification. Radiologic and surgicopathological overall TNM staging are frequently concordant, although radiologic T staging is often incorrect.

Bilateral renal cell carcinoma in a child

Renal cell carcinoma is a rare renal tumor in the pediatric population with an incidence of 0.1-0.3%. We report on the first case of bilateral renal clear cell carcinoma that was treated by partial nephrectomies. We performed a complete genetic evaluation to exclude a family inheritance and we looked at the deletions associated with the possible histologic subtypes of renal cell carcinoma. The patient had no evidence of recurrence after 80-month follow-up and her renal function remained normal.

Renal cell carcinoma presented with hypocalcemia in an adolescent

Renal cell carcinoma is very rare in childhood. It is a different entity from its adult counterpart. We report a case of renal cell carcinoma presented with hypocalcemia in a 16-year-old girl that is, to the best of our knowledge, the first such published incident. The patient was treated by radical nephrectomy with regional lymphadenectomy. Hypocalcemia amended after surgery. Neither chemotherapy nor radiotherapy was given. She has remained disease free for 34 months.

Contemporary use of nephron-sparing surgery for children with malignant renal tumors at freestanding children's hospitals

OBJECTIVE

It is widely accepted that, when feasible, nephron-sparing surgery (NSS) is preferable to radical nephrectomy (RN) for treatment of renal tumors in adults. However, RN is more frequently used in children. We sought to compare in-hospital outcomes after NSS and RN for malignant pediatric renal tumors.

MATERIAL AND METHODS

The pediatric health information system (PHIS) combines data from more than 40 North American pediatric hospitals. We queried PHIS to identify children with malignant renal tumors who underwent surgery from 2003 to 2009. We examined whether outcomes (complication rates, cost, and length of stay) differed by procedure type. Multivariate regression models were used to adjust for confounding, and generalized estimating equations were used to adjust for hospital clustering.

RESULTS

We identified 1235 children with renal tumors who underwent RN (91%) or NSS (9%). Patients undergoing RN and NSS had similar median comorbidity scores (P = .98), hospital lengths of stay (each 6.0 days, P = .54), in-hospital charges, ($25,700 vs $37,000, P = .11), and surgical complication rates (16.4 vs 20.5%, P = .24). These outcomes remained similar after adjusting for other patient and hospital factors.

CONCLUSIONS

Most children with malignant renal tumors treated at children's hospitals undergo RN. RN and NSS use were not significantly different in terms of their length of hospital stay, in-hospital charges, and complication rates. Although oncological outcomes are lacking, these data suggest that NSS may be performed in selected children with malignant renal tumors without significantly increasing their hospital charges, length of stay, or surgical complication rates.

[Renal cell carcinoma in children: Report of a case with lymph node involvement]

Renal cell carcinoma (RCC) in children is rare. This entity has different clinical and biological presentation characteristics from adult RCC. In contrast to Wilms tumor, the efficacy of chemotherapy and radiation therapy in pediatric RCC remains uncertain. Debate continues on the importance of lymph node dissection. The authors present a case of RCC with lymph node involvement in a 12-year-old boy. The treatment was radical nephrectomy and a limited lymphadenectomy. No adjuvant therapy was given. After 13 months of follow-up, there is no evidence of recurrence. This case shows that lymph node involvement (in the absence of distant metastases) is not associated with a poor prognosis in pediatric RCC and that lymphadenectomy in lymph node-positive cases is important.

Renal cell carcinoma in children and adolescents

Although rare in children and adolescents, renal cell carcinomas (RCCs) raise important questions concerning the best treatment approach and accurate pathologic classification. The differences emerging between childhood and adulthood RCC probably prevent any direct generalized application of therapies to children that are validated for adults. The translocation type of RCC, which forms a distinct category characterized by translocations involving Xp11.2 or, less frequently, 6p21, has recently emerged as the predominant type of RCC in children and adolescents, whereas it is rarely diagnosed in adults. This new finding emphasizes how important it is to prospectively classify RCCs in children with standardized 'modern' diagnoses. The standard cornerstone of therapy for RCC in children and adolescents remains radical nephrectomy. Nephron-sparing surgery is currently recommended in adults for selected small-volume tumors, but additional data are needed before this experience can be extensively transferred to the pediatric population. The therapeutic value of complete retroperitoneal lymph node dissection is still controversial, especially in patients without suspected nodal involvement, be they adults or children. The backbone of systemic therapies for adult RCC has recently been changed by the introduction of drugs designed to target tumor-related angiogenesis and signal transduction. It is worth noting that the largest clinical efficacy trials on targeted molecules have been conducted on clear-cell RCC. While targeted drugs have become the standard of care for adult metastatic RCC, there are currently no published reports on their role in children, and their use should be considered for patients with unresectable metastatic or advanced-stage RCC. On the other hand, the utility of targeted therapies in the adjuvant setting remains to be seen for both adults and children.

Xp11.2 Translocation Renal Cell Carcinomas Have a Poorer Prognosis Than Non-Xp11.2 Translocation Carcinomas in Children and Young Adults: A Meta-analysis

Objectives. Renal cell carcinomas (RCCs) in children and adolescents are much rarer than in adults. In this age group, Xp11.2 translocation RCCs were the most common subtype of pediatric RCCs. Information regarding the clinical behavior of pediatric RCCs remains controversial because of their relatively rare incidence. The authors aimed to perform a systematic review and meta-analysis to better define the biological features of pediatric RCCs. Methods. Eligible studies were identified through multiple search strategies. Studies were assessed for quality using the Jadad Quality Scale. Data were collected comparing overall survival (OS), disease-free survival (DFS), and stage in patients with TFE3 + pediatric RCCs and TFE3 − RCCs. Results. A total of 4 studies were included for meta-analysis, and pooled odds ratios (ORs) with 95% confidence interval (CI) were calculated. The meta-analysis outcomes showed that TFE3 + pediatric RCCs were significantly associated with poorer outcomes (OS and DFS) and a higher stage (III/IV) than TFE3 − RCCs (pooled ORs for each group: 4.59 [95% CI = 1.46-14.42] for OS; 5.79 [95% CI = 1.85-18.16] for DFS; and 5.89 [95% CI = 2.23-15.52] for stage). This result was also confirmed by OS and DFS curves ( P = .005 and P = .001). Conclusions. Xp11.2 translocation carcinomas appear to have a poorer prognosis than non-Xp11.2 translocation carcinomas in children and young adults.

Pediatric non-Wilms renal tumors: subtypes, survival, and prognostic indicators

BACKGROUND

To determine the outcomes and predictors of survival for pediatric non-Wilms renal tumors (NWRT).

METHODS

The SEER database (1973-2005) was queried for all patients < 20 y of age.

RESULTS

Overall, 349 cases of NWRT were identified. The major histologic groups included renal cell carcinoma (RCC) (44%), clear cell sarcoma of the kidney (CCSK) (17%), and malignant rhabdoid tumor (MRT) (12%). A bimodal age distribution was observed, with tumors commonly presenting in patients ≤4 y of age and ≥15 y of age. More than 50% of RCC presented at ≥15 y of age, whereas ≥80% of CCSK or MRT patients were ≤4 y of age. Most RCC (57%) and CCSK (53%) were locally staged while most MRT presented with distant disease (51%, P < 0.001). Overall 10-y survival was 63% with improved survival observed in patients with CCSK (79%) and RCC (70%) versus MRT (29%, P < 0.001). By univariate analysis, surgical resection was associated with improved overall 10-y survival (68% versus 30%, P < 0.001), while no benefit was observed for radiotherapy (60% versus 63%, P = 0.8). By multivariate analysis, worse overall survival was observed for patients ≥ 10 y old (HR 4.01, P = 0.013) and those with advanced disease (HR = 12.78, P < 0.001). Patients with MRT (HR = 11.61, P < 0.001) and CCSK (HR = 3.68, P = 0.038) had significantly worse prognosis compared with those with RCC. Surgical resection improved overall survival (HR = 0.36, P = 0.001).

CONCLUSION

For pediatric NWRT, younger patients and those with RCC have improved survival, while a diagnosis of MRT portends a worse prognosis. Surgical extirpation significantly improves survival for all patients.

A rare type of renal cell carcinoma in a girl: hybrid renal cell carcinoma

Hybrid renal cell carcinoma (HRCN) is a rare type of renal tumor with characteristic pathologic features, including oncocytic and chromophobe cellular content, and shows more favorable prognosis than renal cell carcinoma. The early-stage tumors show favorable outcome, and postoperative regular clinical and radiological follow-up is adequate in most cases. However, close follow-up is mandatory for tumors with histopathologically coexistence of squamous, papillary, and/or eosinophilic RCC component. This report describes a 12-year-old girl with a stage I HRCN who was closely followed after nephrectomy with no further treatment.

Renal Cell Carcinoma in Children and Young Adults: Clinicopathological, Immunohistochemical, and VHL Gene Analysis of 46 Cases With Follow-up

To further study the characteristics of renal cell carcinoma (RCC) in young patients and better define their biological features, 46 RCCs of patients younger than 25 years were morphologically and immunohistochemically characterized with follow-up. Loss of heterozygosity (LOH) analysis of the von Hippel—Lindau (VHL) gene region and screening for VHL gene mutations were performed in all tumors. Applying the 2004 WHO classification for RCC, there were 19 Xp11.2 translocation RCCs, 9 clear cell RCCs, 17 papillary RCCs, and 1 unclassified RCC. All 19 Xp11.2 translocation RCCs showed moderate to strong immunoreactivity for TFE3. None had TFEB immunoreactivity. One Xp11.2 translocation RCC had an unreported morphology with empty or ground glass nuclei, occasional nuclear grooves, inconspicuous nucleoli and abundant mucinous material in stroma.VHL gene analysis revealed deletions at 3p25-26 in 1 clear cell RCC and 1 papillary type 2 RCC. The papillary type 2 RCC was also presented with a family history of VHL disease and found a germline mutation G → C on a splicing site at position 553+5. The present case widens the spectrum of microscopic features to be found in VHL-associated RCC. There were no VHL mutations in the remaining 45 RCCs. Statistical analysis of stage and outcome revealed that TFE+ pediatric RCCs were significantly more frequently associated with a higher pTNM pT3/pT4 stage and a poorer outcome than TFE-RCCs ( P < .05). Owing to the already known aggressive behavior of these Xp11.2 translocation RCCs, patients with TFE+ pediatric RCCs should benefit from a stricter follow-up.

Renal cell carcinoma originating in a renal cyst in a 12-year-old girl

We report a 12-year-old girl with renal cell carcinoma originating in a cyst of the left kidney. Ultrasonography revealed 2 small hyperechoic masses in the luminal side of a cyst. Although hypervascularity was not detected in the cyst by computed tomography, the possibility of malignancy could not be ruled out because of the presence of 2 solid masses. Therefore, partial left nephrectomy was performed. On histopathologic examination, the 2 solid masses within the cyst were found to be renal cell carcinoma. This patient remains disease-free at 4 years after partial nephrectomy.

Renal cell carcinoma in children: single-center experience

PURPOSE

The aim of the study was to report the experience with renal cell carcinoma (RCC) in children.

MATERIALS AND METHODS

We conducted a retrospective study on renal adenocarcinoma cases treated in our center between 1993 and 2008. The age limit was established at 15 years. We collected data on personal history, diagnostic age, sex, clinical presentation, tumor laterality, diagnostic procedure, and tumor stage according to TNM classification proposed by the International Union Against Cancer (2002), surgical technique, pathologic subtype, and outcome.

RESULTS

Six children were included in this study (4 girls and 2 boys) with a mean age of 9.5 years (range, 4-14 years). Tumor affected the right side in 4 patients and the left side in 2. Follow-up ranged from 9 to 140 months (mean, 85). Two patients were diagnosed as stage T1aN0M0, another was T1bN2M0, and 2 were T2N0M0, whereas the last one was T3N2M0. Radical nephrectomy was performed in 5 patients, whereas partial nephrectomy was adopted in one patient. The most common histologic subtype was translocation morphology RCC. One patient had local recurrence, whereas the other 5 are currently disease-free.

CONCLUSION

Renal cell carcinoma is a rare histologic type of tumor in children, with certain features that differ from those in adults. In general, RCC in children tends to present later than Wilms' tumor and is usually associated with signs and/or symptoms of disease. In localized cases, the treatment of choice is radical nephrectomy.

Pediatric renal cell carcinoma

Renal cell carcinoma (RCC) comprises about 5% of pediatric renal neoplasms. It has been recognized as a second malignancy in multiple reports. It is generally symptomatic at diagnosis, and most children with RCC present with more locally advanced disease than do adults. Contemporary investigation of pediatric RCC has demonstrated that a large percentage of these tumors bear cytogenetic translocations involving the MiT family of transcription factors. Surgical therapy for these children resembles operative intervention for adult RCC, though debate continues about the precise role of lymph node dissection. There are no adequately powered studies to support conclusions about adjuvant or neoadjuvant chemotherapy for children with RCC. This may be ameliorated by a multi-institutional protocol which is enrolling patients.

Renal cell carcinoma in the pediatric population: Results from the California Cancer Registry

BACKGROUND

Renal cell carcinoma (RCC) is a rare disease in children and adolescents. This study aimed to review epidemiologic characteristics and survival for pediatric RCC patients using a large, population-based database.

PROCEDURE

The California Cancer Registry (CCR) was reviewed from 1988 to 2004. All cases of RCC in patients younger than 21 years were identified and annual age-adjusted incidence rates were determined for the overall population and subdivided by ethnicity. Tumors were classified by stage and grade, and actuarial mortality rates were calculated.

RESULTS

From 1988 to 2004, 43 cases of RCC were identified in patients younger than 21 years, accounting for 4.3% of all renal tumors in this age group. The overall annual age-adjusted incidence was 0.01/100,000 with the tumor more common in non-Hispanic blacks (0.03/100,000) compared to non-Hispanic whites (0.01/100,000), Hispanics (<0.01/100,000), and non-Hispanic Asians/Pacific Islanders (<0.01/100,000). The mean age at presentation was 15.4 years (SD 4.03, SE 0.615). RCC was identified more frequently in females (58.14%). At the time of presentation, 53.49% of tumors were localized, 20.93% were regionally advanced, and 25.58% were metastatic. The observed actuarial survival at 5 and 10 years was 61% (+/-15.7%).

CONCLUSION

Pediatric RCC is an uncommon and aggressive tumor that occurs most frequently in children in the second decade of life, more often in females and blacks. The epidemiological characteristics of this tumor differ from adult RCC and Wilms tumor, suggesting its distinctive biology and potential need for alternative treatment strategies.