Renal cell carcinoma in children

Approach to Persistent Microscopic Hematuria in Children

Persistent isolated microscopic hematuria is relatively common in pediatric practice, affecting around 0.25% of children. Isolated microscopic hematuria can be caused by a myriad of potentially benign or serious causes, including urologic issues; kidney stones; glomerular diseases, including disorders of the glomerular basement membrane; hematologic abnormalities; and others. The challenge for the pediatrician or pediatric nephrologist is to distinguish children with potentially progressive forms of kidney disease versus other causes while minimizing cost and inconvenience for the child and family. This manuscript will review the multiple potential causes of microscopic hematuria and provide a framework for the initial evaluation and monitoring of such 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.

[The translocation carcinoma: A pediatric renal tumor also in adults]

The MiT family of translocation-associated renal cell carcinomas comprise approximately 40 % of renal cell carcinomas in young patients but only up to 4 % of renal cell carcinomas in adult patients. The Xp11.2 translocation-associated tumors are the most frequent and were included in the 2004 World Health Organization (WHO) classification. They contain a fusion of the TFE3 gene with ASPSCR1, PRCC, NONO, SPFQ or CLTC resulting in an immunohistochemically detectable nuclear overexpression of TFE3. The Xp11.2 translocation-associated renal cell carcinomas are characterized by ample clear cytoplasm, papillary architecture and abundant psammoma bodies. The TFEB translocation-associated renal cell carcinomas are much rarer and show a biphasic architecture. Fluorescence in situ hybridization permits the detection of a translocation by means of a break apart probe for the TFE3 and TFEB genes and is recommended for the diagnosis of renal cell carcinomas in patients under 30 years of age. The TFE3 and TFEB translocation-associated tumors are classified as MiT family translocation carcinomas in the new WHO classification.The rare renal cell carcinomas harboring an ALK rearrangement with fusion to VCL in young patients with sickle cell trait show a characteristic morphology and are listed in the new WHO classification as a provisional entity.

Metastatic renal cell carcinoma in children and adolescents: a 30-year unsuccessful story

BACKGROUND

Because of the rare occurrence of renal cell carcinoma (RCC) among children very little is known about this malignancy in pediatric age. We aimed adding knowledge on the clinical characteristics and outcome of metastatic (m) RCC in children and adolescents.

PATIENTS AND METHODS

The series included 14 stage 4 RCC patients with a median age at diagnosis of 155.5 months, observed at the Italian Pediatric Hematology and Oncology Association (AIEOP) centers from January 1973 to November 2010. We were able to reevaluate histopatology of 11 out of the 14 patients and perform immunostaining for TFE3 in 9 out of the 11 patients.

RESULTS

Of the 14 patients under study, 5 (3 girls) had a translocation morphology TFE+ RCC, 2 were reassigned as papillary type 1 or 2, respectively, 2 tumor specimens with primary clear cell histology had confirmed the initial histologic diagnosis, and 2-whose biopsy specimen was insufficient-had the diagnosis of RCC not further specified with subtyping. In the remaining 3 cases, the initial diagnosis of clear cell carcinoma was left. Overall, 6 patients received chemotherapy, 9 immunotherapy, and 2 adjuvant antiangiogenic therapy. Overall, 11 patients (78.5%) never achieved complete remission and died from progressive disease 1 to 16 months after diagnosis (median overall survival 5.5 mo). Three patients, 2 of whom received adjuvant antiangiogenic therapy, relapsed to lung at 3, 6, and 8 months after diagnosis, and died 18, 32, and 33 months after diagnosis, respectively.

CONCLUSIONS

Despite their possibly different biology, childhood and adult mRCC seems to be sharing comparable outcomes. Because of the very low incidence of mRCC (about 20%) in children and adolescents, an international pediatric cooperation to address biological studies and assess the novel targeted approaches is needed.

Renal tumors in the second decade of life: results from the California Cancer Registry

BACKGROUND

Renal tumors are rare in adolescents and young adults. The aim of this study was to characterize the histologic condition, epidemiology, and survival of renal tumors in patients aged 11 to 20 years old using a large, population-based database.

METHODS

The California Cancer Registry was reviewed from the years 1988 to 2004. All renal tumors in patients aged 11 to 20 years old were identified. The data were analyzed with relation to patient age, sex and ethnicity, tumor histologic examination, and actuarial mortality rates.

RESULTS

Seventy-seven primary renal malignancies were identified. Thirty-nine (51%) were renal cell carcinoma, 23 (30%) were Wilms' tumor, and 15 (20%) were other tumor types. The mean age of the patients with renal cell carcinoma was 16.7 years old, which was significantly older than the Wilms' tumor patients (13.9 years; P < .01). The 5-year cumulative survival rate of patients with renal cell carcinoma was 54%, which was worse than that of Wilms' tumor patients (77%).

CONCLUSION

Primary renal malignancies are uncommon in the second decade of life. The most common tumor type in this age-group is renal cell carcinoma followed by Wilms' tumor. Patients with renal cell carcinoma tend to be older and have a lower survival than patients with other kidney tumors.

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.

Part II: Treatment of primary malignant non-Wilms' renal tumours in children

Renal-cell carcinoma, clear-cell sarcoma, (congenital) mesoblastic nephroma, rhabdoid tumour, and renal medullary carcinoma form a heterogeneous group of childhood renal malignancies known as non-Wilms' tumours. Progress has been slow in improving the management of these tumours to decrease morbidity and increase survival. However, greater cooperation between national and international centres should engender specialisation, and an increased knowledge of the molecular biology of these tumours will inevitably lead to substantial progress over the next decade. This review is the second of two parts: the first part provided an updated review of the clinical presentation, imaging, and pathology of non-Wilms' tumours and this second part provides an updated review of the treatment of these tumours.

Population-based study of renal cell carcinoma in children in Germany, 1980-2005: more frequently localized tumors and underlying disorders compared with adult counterparts

BACKGROUND

Childhood renal cell carcinomas (RCCs) differ histologically and biologically from their adult counterparts. The characteristics of RCC-affected children and their tumors, the influence of treatment, and outcome have so far not been studied in a nonselected, population-based cohort.

METHODS

A retrospective analysis was undertaken of RCC patients less than 16 years old reported to the German Childhood Cancer Registry and to the Kiel Paediatric Tumor Registry from 1980 to 2005.

RESULTS

Forty-nine RCC in children (24 boys, 25 girls) with a median age of 10.6 years were identified. In about every third child possibly RCC-related underlying disorders (tuberous sclerosis, neuroblastoma, teratoma with chemotherapy, Saethre-Chotzen syndrome, chronic renal failure) or related diseases in their family were found. The pathologic subtypes were papillary in 16 (33%), translocation type in 11 (22%), unclassified in 8 (16%), and rarely clear-cell (n = 3) or others. Thirty-four (69%) patients had localized RCC, 8 (16%) patients regional lymph node metastases, and 4 (8%) patients distant metastases. Event-free survival and overall survival rates at 5 years were 96% for localized RCC, 69% and 75% for regional lymph node-positive, 25% and 33% for distant metastatic RCC, respectively. Two of 4 patients with distant metastases received immunotherapy combined with chemotherapy and surgery, both are alive, 1 of them disease-free for 6.9 years.

CONCLUSIONS

Pediatric RCCs are predominantly localized diseases. Children with RCC frequently suffer underlying disorders. Survival rates in localized and regional lymph node-positive cases are favorable. Because of the rarity of RCC in childhood, an international study is necessary.

Cytogenetic findings in pediatric renal cell carcinoma

Adenocarcinomas of the kidney are rare childhood tumors. Only 30 cases with chromosomal abnormalities have been reported, and neither their karyotypic characteristics nor the molecular mechanisms behind their pathogenesis are clear, except for a special group of papillary tumors characterized by X-chromosome abnormalities. We have cytogenetically analyzed short-term cultured cells from two pediatric renal carcinomas, one papillary, and one chromophobe renal cell carcinoma, revealing the following karyotypes: 58-60,XX,-X,-1,+7,-8,-9,-11,-14,-15,+17,-18,-19,-21,-22 and 36,X,-X,-1,-2,-5,-6,-9,-10,-13,-17,-21/37,idem,+r/36,idem,-14,+1-2r, respectively. The findings indicate that subsets of pediatric renal cell carcinoma show karyotypes that are similar to their adult counterparts.

Pediatric renal cell carcinoma: clinical, pathologic, and molecular abnormalities associated with the members of the mit transcription factor family

We describe the clinical features, outcome, pathology, cytogenetics, and molecular aspects of 13 pediatric papillary renal cell carcinomas during a 19-year period. Seven cases (54%) had translocations involving Xp11.2 (TFE3). They were identified by cytogenetic, molecular, and/or immunohistochemical analyses. All Xp11.2+ translocations were TFE3+ by immunostaining. Cytogenetic and/or polymerase chain reaction analyses identified 3 cases with t(X17) and 1 case with t(1;17), and all had additional translocations. Histologic features in common in TFE3+ tumors also were present in some TFE3- tumors. One TFE3- tumor had complex cytogenetic abnormalities, 55XY,+2,del(3)(p14),+7,+8,+12,+13,+16,+17,+20[11 ], and 2 cases had normal karyotypes. None had t(6;11)/TFEB+ immunostaining. Five cases had focal, weak MITF tumor immunostaining. The key clinical findings were as follows: (1) The presence of an Xp11.2 (TFE3) translocation frequently is associated with advanced stage at initial examination. (2) All patients who underwent complete, partial nephrectomy with clear margins (adequate only for stage 1) and resection of metastases were alive and relapse-free at last follow-up. (3) The mean +/- SD event-free survival and overall survival rates at 5 years were both 92% +/- 7.4%. (4) One patients with a TFE3+ and MITF+ tumor and 66-87,XXY,der(1)t(1;8)del(4)(q?) der(11)t(11;15)der17t(X;17 abnormalities died 9 months after diagnosis.

Renal cell carcinoma: Children's Hospital Boston experience

OBJECTIVES

To review our experience to better define pediatric renal cell carcinoma (RCC). Pediatric RCC is rare, and recent data suggest it may be a unique disease.

METHODS

A retrospective review was conducted of hospital and pathology records from 1965 to 2003. Patients with RCC were identified, and the clinical and pathologic data were extracted.

RESULTS

Since 1965, 11 patients with RCC were treated, accounting for 3% of all renal tumors. In the first 20 years, 191 patients with renal tumor were treated, of whom 3 had RCC. In the most recent 15 years, 172 patients with renal tumor were treated, of whom 8 had RCC. The mean age at presentation was 14.7 years (range 9 to 17 years), with a female predominance (2.7:1). The clinical signs and symptoms included hematuria in 36%, flank pain in 27%, and an abdominal mass in 9%; 36% were discovered incidentally. Of the 11 RCC tumors, 45% were papillary and 55% were clear cell carcinoma. Papillary tumors presented at a worse stage and displayed more aggressive clinical behavior. Of 10 patients with available follow-up data, 6 had no evidence of RCC, 1 had died of other causes, 2 had died of metastatic RCC, and 1 was alive with recurrent RCC at a mean follow-up of 4.9 years.

CONCLUSIONS

The clinical presentation, pathologic characteristics, and clinical behavior of pediatric RCC are different than those for adult RCC. A possible increasing incidence of RCC in children would parallel an increased incidence in adults. Our findings warrant additional and coordinated efforts to better characterize RCC in children.

Renal cell carcinoma: case report and literature review

Renal cell carcinoma arising from epithelial cells of the renal tubule is a highly aggressive and malignant tumor in all ages. Less than 2% of cases occur in childhood, relatively in older age group. Only a few pediatric series have been presented in the English literature. Tumor is presented with characteristic findings of flank pain, gross hematuria, and palpable mass. Although one half of the patients have metastasis at the time of diagnosis, most cases are currently being incidentally detected using improved imaging techniques. The overall prognosis in children appears to be similar to that in adults. Tumor stage and complete surgical resection have been reported as the most meaningful prognostic factors for the outcome. The incidence of metastatic disease is same as in adults. The effect of chemotherapy and immunotherapy, either preoperatively or postoperatively, is unclear. Cure is the most likely consequence in localized and completely resected tumors. Here, we present an 8-year-old boy with renal cell carcinoma demonstrating only hematuria without any pathological physical examination findings. The mass was described by abdominal ultrasonography and computed tomography in the left kidney. After the left nephroureterectomy, the patient was given no therapy.

Pediatric renal carcinoma associated with Xp11.2 translocations/TFE3 gene fusions and clinicopathologic associations

Renal cell carcinomas (RCCs) are rare in children and studies of their subtypes and clinicopathologic associations are limited to small series. We identified 8 patients with RCC treated at our institution between 1981 and 2003, reviewed their clinicopathologic features, cytogenetics findings, and evaluated the status of TFE3 expression by immunohistochemistry and numerical chromosomal alterations by interphase fluorescent in situ hybridization on paraffin-embedded tissue. These 8 patients (5 female and 3 male) had diploidy, and 5 had morphologic features compatible with the recently described RCC associated with Xp11.2 translocations/TFE3 gene fusions and demonstrated nuclear labeling for TFE3 protein by immunohistochemistry. The translocation was confirmed in 2 of these 5 patients by conventional cytogenetics. One case was a high-grade nonpapillary RCC and the other was compatible with type 2 papillary RCC. Four patients showed at least 1 chromosomal gain including trisomy 7 and/or trisomy 17. None of the tumors from male patients showed evidence of loss of the Y chromosome, but 2 patients showed numerical abnormalities of X chromosome +add(X). Two patients had sickle cell disease, and 1 of these also had stage IV-S neuroblastoma. This study suggests that many cases of RCC in children reported under the terms "papillary" and "clear cell" likely represent Xp11.2 translocation/TFE3 gene fusion-associated RCC. It also emphasizes the unusual associations of RCC with neuroblastoma and sickle cell hemoglobinopathy, which need further study.

Local lymph node involvement does not predict poor outcome in pediatric renal cell carcinoma

BACKGROUND

Local lymph node involvement in adults with renal cell carcinoma (RCC) is associated with poor outcome. The prognostic significance of local lymph node involvement in children with RCC has not been studied systematically.

METHODS

A retrospective review of patients treated at St Jude Children's Research Hospital (Memphis, TN) and an extensive review of the medical literature were undertaken to evaluate the prognostic significance of local lymph node involvement in pediatric RCC.

RESULTS

Thirteen patients with the diagnosis of RCC were treated at St. Jude since the hospital's inception in 1962. Four patients presented with lymph node-positive, distant metastasis-negative (N + M0) disease, and all 4 remain disease free after resection without adjuvant therapy (follow-up duration, 2-9 years). A systematic review of the literature including 243 pediatric patients with RCC revealed stage-specific survival rates of 92.5%, 84.6%, 72.7%, and 12.7% for Stage I-IV disease, respectively. Of 58 children with N + M0 RCC for whom outcome data were available, 42 (72.4%) were alive without disease at last follow-up. Among patients whose therapy could be discerned, those who received no adjuvant therapy fared as well (15 of 16 alive) as those who received various adjuvant treatments (22 of 31 alive).

CONCLUSIONS

Children with lymph node-positive RCC in the absence of distant metastatic disease had a relatively favorable long-term prognosis, with survival rate nearly triple those of adult historical controls. Until highly effective therapies for RCC are identified, these children should not be exposed to adjuvant treatment. Further investigation of the biologic differences between adult and pediatric RCC is warranted.

Renal cell carcinoma in children: a clinicopathologic study

PURPOSE

To identify the prognostic factors, treatment, and outcome of children affected by renal cell carcinoma (RCC).

PATIENTS AND METHODS

The series included 41 patients (18 males and 23 females) with a median age of 124 months observed at the 11 Italian Association for Pediatric Hematology and Oncology centers from January 1973 to January 2001. Clinical data, surgical notes, pathologic findings, and summaries of therapy were taken from the charts.

RESULTS

Seven (17%) of the 41 patients had a papillary histology, and 34 (82.4%) had nonpapillary histology. Eighteen patients (43.9%) had stage I, one patient (2.4%) had stage II, two patients (4.8%) had stage IIIA, 10 patients (24.3%) had stage IIIB, and nine patients (21.9%) had stage IV disease. One patient had a bilateral involvement at diagnosis. Seven patients experienced disease recurrence. Lung and liver were the most common distant lesions and usually were fatal. In this study, the major factor influencing the prognosis was the stage. Event-free survival at 20 years was 53.5% for all patients. Overall survival at 20 years was 54.9% for all patients.

CONCLUSION

RCC is a rare disease in children and adolescents. This neoplasm has a different clinical presentation in children compared with adults but the same outcome. In our experience, patients with localized disease could be cured by nephrectomy alone. Prospective studies in a larger number of patients are needed to confirm radiation therapy and biologic response modifiers as effective adjunct therapy in RCC stage III. The alternative therapy seems warranted in patients with advanced disease.

Treatment of childhood renal cell carcinoma with lymph node metastasis: two cases and a review of literature

Standard treatment for renal cell carcinoma (RCC) is radical nephrectomy with lymph node dissection. Stages I and II have encouraging prognoses, but Stage III with regional lymph node metastasis can be unfavorable. Adjuvant therapy for pediatric patients with advanced RCC with lymph node involvement or metastatic lesion has not been defined. Advanced pediatric RCC is reported in two patients (boys, aged 6 and 9 years: Stage IIIs, Robson; Stage III and IV, pTNM classification) treated by nephrectomy and lymph node dissection followed by postoperative interferon-alpha (IFN), that can be used as an adjuvant therapy with side effects such as fever, bone marrow suppression, or decreased liver function. One is doing well for 7 years, another is suffered from lung metastases at 3 years after surgery. Although immunotherapy is expected to improve survival in pediatric patients with advanced RCC, surgical resection of renal and metastatic tumors remains the standard treatment.

Non-Wilms' renal tumors in children

Renal tumors other than Wilms' tumors are infrequent in childhood. Wilms' tumors account for 6% to 7% of childhood cancer, whereas the remaining renal tumors account for less than 1%. The most common non-Wilms' tumors are clear cell sarcoma of the kidney, rhabdoid tumor of the kidney, renal cell carcinoma, mesoblastic nephroma, and multilocular cystic nephroma. Collectively, these tumors account for less than 10% of the primary renal neoplasms in childhood.

Oncocytoid renal cell carcinoma after neuroblastoma: a report of four cases of a distinct clinicopathologic entity

Four children who developed oncocytoid renal cell carcinoma (RCC) after neuroblastoma are reported. One patient had multiple, bilateral RCCs. The mean age at time of diagnosis of RCC was 8.8 years (range, 5-13 years). The mean interval between neuroblastoma and RCC was 7.15 years (range, 3.1-11.5 years). The histologic findings of these RCCs did not fit within the spectrum of known renal epithelial neoplasms. Most of the neoplastic cells in all cases had eosinophilic, oncocytoid cytoplasm and were arranged in solid and papillary growth patterns. A subset of cells with reticular cytoplasm was also present. Immunohistochemical studies demonstrated keratins 8 and 18 in all neoplasms and keratin 20 in two cases. DNA ploidy analysis revealed that two of three neoplasms assessed were aneuploid. Cytogenetic studies revealed 45, XX, add or dup (7)(q32q36) in one neoplasm, and 83-89, XXXX, -1 ,-3, del (3)(q11.1q2?1), der(4)t(4;?22) (q32;q11.2), -14, -22 in a second tumor. Microsatellite polymerase chain reaction analysis detected no abnormalities in one neoplasm and allelic imbalance of chromosomes 2p31-32.2, 8p22, 9p22-24, 13q22, 20q13, and 22q11 in a second tumor. In case 4, two different RCCs excised 6 months apart were analyzed. The initial neoplasm showed allelic imbalance of chromosomes 2q31-32.2, 5q22, 5q31, 10p13-14, 13q22, 14q31, and 20q13. The subsequent neoplasm showed allelic imbalance of chromosomes 3p21.3, 14q31, and 20q13. The common presence of 14q31 and 20q13 abnormalities suggests that these two neoplasms were genetically related. In aggregate, these findings are distinctive, are not found in known types of RCC, and support the morphologic impression that oncocytoid RCC after neuroblastoma is a distinct clinicopathologic entity.

Renal cell carcinoma in children under 14 years old: long-term survival

OBJECTIVES

To assess the treatment and long-term survival of children under 14 years old operated upon for renal cell carcinoma (RCC).

PATIENTS AND METHODS

The records of five patients (aged 2, 4, 6, 9 and 13 years) who had been treated for RCC between 1982 and 1993 were reviewed. All had undergone nephrectomy with (two) or without (three) regional lymphadenectomy. After surgery four patients received chemotherapy (vincristine with actinomycin-D, three, vinblastine, one), and two with advanced-stage disease received other agents (interferon alpha, interleukin-2). They were followed for 5 to 15 years.

RESULTS

Three patients with stage I-II RCC were well at 13, 15 and 15 years after treatment. Of the two patients with regional lymph node involvement (stage III), one was well 5 years after surgery while the other developed hepatic, lung and bone metastases, and died 2 years after presentation.

CONCLUSION

The prognosis and long-term survival of children under 14 years old with RCC is very good for those with low-stage tumours. Nephrectomy with complete tumour extirpation is the main mode of treatment. For advanced-stage tumours, the role of adjuvant chemotherapy and/or biological agents must be defined more clearly.

Long term survival in a young girl with renal cell carcinoma

A young girl with an uncommon renal tumour is the subject of this communication. A diagnosis of renal cell carcinoma was established post-operatively. Combined modality treatment including chemotherapy and radiotherapy has helped achieve a disease free survival of nearly 5 years.

Renal-cell carcinoma in children: a different disorder from its adult counterpart?

BACKGROUND

Renal-cell carcinoma (RCC) is a rare tumor in children. To address whether RCC in children differs from its adult counterpart, we report a series of 16 children with RCC (5 boys, 11 girls, mean age 9.6 years, range 3-19 years) presenting between 1979 and 1996 at three pediatric centers.

PROCEDURE

Pathology showed papillary RCC in five patients (31%). Nonpapillary tumors were present in 11 (69%), of which nine were clear-cell type (56%), one was chromophobe-cell type (6%), and one was granular-cell type (6%). Cytogenetic studies were performed on four.

RESULTS

In two tumors, normal karyotypes (45,XX or 45,XY) were found. In another, there were translocations: t(X;1), t(X;2) and t(6;14). In the fourth, analysis revealed 46,XX/46,X,t(X;17)(p11.2;q25),t(1;12). Several features in this series differ from those reported in adults. In adults, RCC is more frequent in males, is usually nonpapillary, and is characterized cytogenetically by deletions or rearrangements in the short arm of chromosome 3. In contrast, in our series there was no male predominance and a higher proportion of papillary tumors. In addition, two of four cytogenetically analyzed tumors had translocations involving the X chromosome. Translocations involving the Xp11.2 locus have been infrequently reported in both adults and children with papillary RCC.

CONCLUSIONS

The higher frequency of papillary histology and the presence of translocations involving Xp.11.2 in two cases raise the possibility of a unique subtype of RCC in children.

Metastatic renal cell carcinoma in a child: 11-year disease-free survival following surgery

A child with metastatic renal cell carcinoma (RCC) is presented. This case is unusual in that the patient has remained disease free for 11 years following surgery and only one course of chemotherapy prior to thoracotomy. The management of metastatic RCC is reviewed and the genetic mechanisms leading to its development briefly discussed.

Partial nephrectomy for pediatric renal cell carcinoma: an unusual case presentation

Nine years after successful treatment of Stage IV neuroblastoma, a 10-year-old white girl was demonstrated to have a complex cystic mass in the upper pole of her solitary right kidney. Partial nephrectomy was performed, disclosing a renal cell carcinoma, predominantly clear cell type. No metastases were detected. Renal cell carcinoma is a rare cause of secondary malignancy. Partial nephrectomy can be used successfully to treat renal cell carcinoma in children.

Renal cell carcinoma in childhood and adolescence: a retrospective survey for prognostic factors in 22 cases

To identify prognostic factors for renal carcinoma in young patients, a retrospective analysis was performed of 22 patients (< or = 21 years of age) with histologically verified renal cell carcinoma. Demographic, staging, and treatment variables were collected in a database, and their effect on survival was determined using Kaplan-Meier probability distribution. The median age was 15.5 years (range, 3 to 21 years), and the male:female ratio was 13:9. Only three patients were black. Histopathologic examination showed 15 clear cell tumors, 4 mixed cell type, 2 papillary, and one well-differentiated adenocarcinoma. The median size of the primary tumor was 10 cm (range, 5 to 20). There were seven patients with stage I tumors, one with stage II, and 14 with stage IV. Complete resection of the primary tumor was accomplished in 12 patients. The overall 5-year survival rate was 30% (confidence interval, 20% to 40%). The 5-year survival rate was better for patients who had complete resection of the primary tumor (60% v 10%). Unresectability was associated with involvement of nodes and/or occurrence of metastases, thus an independent effect of complete resection on survival could not be demonstrated. The data showed that age, tumor size, location, and histology were not predictors of outcome; tumor stage and complete surgical resection were the only meaningful prognostic factors. The presentation of renal cell carcinoma as a localized or systemic disease may reflect a twofold biological behavior. In the first group, the disease is curable with resection, in the second, it is unaffected by surgery or adjuvant therapy. In light of the very low incidence of this renal malignancy in childhood, prospective multicenter studies will be required to improve the poor therapeutic results.

Anaplastic renal cell carcinoma following neuroblastoma

Renal cell carcinoma is unusual in children. We report a case of anaplastic renal cell carcinoma arising in a 7-year-old girl following treatment for Stage III neuroblastoma. The renal cell carcinoma has unusual histologic and ultrastructural features, which are discussed. The case is further unusual in that few children with advanced stage neuroblastoma survive long enough to develop second malignant neoplasms.

Pediatric renal cell carcinoma: a complete response to recombinant interleukin-2 in a child with metastatic disease at diagnosis

Renal cell carcinoma is a rare pediatric malignancy that appears to have a similar clinical outcome in children and adults. We review the experience of Childrens Hospital Los Angeles and compare it with the published pediatric series, reporting on seven cases from 1954 to the present. As in earlier pediatric series, we find that Stage I/II patients do well (five of five complete responses with prolonged disease-free survival) with surgical resection. As in other pediatric series, our only Stage III patient died of disease. We also report on a recent case of renal cell carcinoma, metastatic to lymph nodes and lung parenchyma at diagnosis (Stage IV). This patient was treated with high dose continuous infusion recombinant interleukin-2 and had a partial response. The patient attained a complete response following a second laparotomy and two subsequent cycles of recombinant interleukin-2. He is presently well, without evidence of disease, 3 1/2 years after diagnosis. The significance of this form of therapy to advanced renal cell carcinoma in childhood is discussed.

Spectrum of differentiation in pediatric epithelial tumors of kidney: report of two cases

Two unusual presentations of childhood renal cell epithelial tumors including one whose unique clinical manifestation was polycythemia are described. One was a renal cell carcinoma which was so poorly differentiated that ancillary histopathologic techniques were necessary to arrive at the correct diagnosis. The other case represented the opposite extreme being so well-differentiated as to raise the differential diagnosis of renal cell carcinoma versus renal cell adenoma with blastemal areas. These case studies exemplify the practical role for specialized histopathologic techniques in diagnosing pediatric renal tumors, which may not be feasibly or even accurately categorized into known renal tumor types using routine diagnostic methods.

Position paper: imaging methods for primary renal tumors of childhood: costs versus benefits

The patterns of disease distribution at diagnosis and during follow-up were cataloged for the primary renal tumors of childhood. These data, derived from more than 1,500 patients, were used to define the most rewarding and cost-effective imaging methods required for patient management. The basic information needed prior to surgery includes whether there is a functioning kidney on the opposite side, and whether there are lung metastases or inferior vena cava thrombi. Simple X-ray examinations and ultrasonography (US) will provide the necessary data. Postoperatively, when the histology is known, examination of the brain (MRI or CT scan) is needed for patients with the rhabdoid tumor and clear cell sarcoma of the kidney (CCSK) who are prone to develop brain lesions; and the skeletal system (bone scan, X-ray skeletal survey) for CCSK and for renal cell carcinoma patients who tend to develop bone metastases. Continuing examination of the lung (chest films) is required for all histologies except perhaps for mesoblastic nephroma, which seldom metastasizes. The opposite kidney needs follow-up (US) for 5 or more years to exclude metachronous involvement if nephrogenic rests are present in either kidney. Sophisticated imaging studies, which cost five times or more than simple X-ray examinations or US, are not warranted routinely, and should be reserved for those cases where simpler, less expensive studies do not suffice for reaching patient management decisions.

Renal cell carcinoma in childhood

The imaging features of renal cell carcinoma in 4 young patients (age 7 to 14 years) are described. A high proportion (75%) showed calcification on plain radiographs or computed tomography (CT). Both patients who underwent CT showed well defined high density tumours which were also echogenic on ultrasound examination. These findings are significantly different to those most commonly seen on studies of the tumour in adults.

Cytogenetics of a renal cell carcinoma in a 17-month-old child. Evidence for Xp11.2 as a recurring breakpoint

A renal cell carcinoma from a 17-month-old boy with a history of maternal hydrocarbon exposure was found to have a 46,Y,t(X;17)(p11.2;q25) karyotype. Although this translocation has not previously been reported, other translocations involving Xp11.2 have been described, suggesting that this may represent a non-random breakpoint involved in the pathogenesis of childhood renal cell carcinoma. Both chromosomes 3 in the tumor were normal by both karyotype and RFLP analysis.

Renal cell carcinoma in children

Six cases of renal cell carcinoma in children between seven and nineteen years of age are reported. These patients differ from those with Wilms tumor chiefly in the age of presentation and response to chemotherapy. Radiographically, renal cell carcinoma cannot be distinguished from Wilms tumor. While the natural history of renal cell carcinoma appears to be similar in children and adults, it may have a more favorable prognosis below the age of ten years.

Renal cell carcinoma in children: histology, immunohistochemistry, and follow-up of 10 cases

Ten renal cell carcinomas in children under 15 years were investigated. The average age was 122.5 months and the girls predominated in our cases (7 girls, 3 boys). By using the classification of Thoenes et al., Pathol Res Pract 181: 125-143, 1986 a predominance of clear cell-eosinophilic tumor cell type and of the tubulopapillary growth pattern was found. Immunohistochemistry revealed a heterogeneity of cytokeratin expression. By using the monoclonal antibodies Cam 5.2 and KL 1, cytokeratins were found in 7 cases each. The other 4 cytokeratin antibodies used were less sensitive. The expression of cytokeratin 13 in 3 cases suggested a more complex histogenesis than assumed. Vimentin was found in 3 tumors, but an association to a higher grade (G) of malignancy was not found in these cases. One tumor expressed the Tamm-Horsfall-protein, which is predominantly found in the distal tubule of the normal kidney. In summary the results of immunohistochemistry characterized the great heterogeneity of these tumors. Follow-up information was available in 9 cases. All patients with G I- and G II-tumors were free of disease after an average time of 39.6 months (mean 27 months). Two of the 3 cases with G III-tumors died after 9 and 15 months, despite additional chemo- or radiotherapy. Therefore tumors of grade I and II of the Thoenes classification seem to have a good prognosis.

Oncocytic renal tubular adenoma (so-called oncocytoma) in seventeen-year-old girl

Renal tubular neoplasms (adenomas or adenocarcinomas) are rare in children or young adults. Herein, we report an oncocytic renal tubular adenoma (so-called oncocytoma) that was found in a seventeen-year-old girl. Preoperative evaluation included aspiration of this tumor, and we suggest that preoperative aspiration is an important procedure in the diagnosis and management of suspected renal tumors in children and young adults.

Long-term follow-up of children with renal carcinoma

Renal carcinoma is a rare tumour in children. The clinical, histological and follow-up details of 6 patients are presented. Haematuria is confirmed as an important indicator of renal pathology. Long-term follow-up suggests that chemotherapy and radiotherapy have little effect on the prognosis in advanced disease.

Selecting initial therapy for pediatric genitourinary cancers

A few decades ago, there were few choices in the initial management of children with genitourinary tumors. Radical surgical removal was the only line of attack that promised any chance of survival. Improvement in the results of multimodal therapy in the last 15 years have radically altered the outlook for these children, hence the choice of therapy. As with other childhood cancers, the choice of therapy is based on risk-benefit evaluations of the roles of surgery, irradiation, and chemotherapy, since all three modalities have their associated morbidities. Current emphases are on preservation of function without compromising cure. The large cooperative clinical trials have emphasized this aspect of pediatric oncology. They have demonstrated, for example, that radiation therapy can be omitted from primary management of early stage Wilms' tumor patients who are given adequate adjuvant chemotherapy as can both radiation therapy and ablative surgery in certain cases of early stage rhabdomyosarcoma. Routine retroperitoneal node dissections have been shown to be of dubious diagnostic or therapeutic value in boys with testicular cancers. The need for bilateral oophorectomy in girls with dysgerminoma can similarly be questioned. Choices of initial therapy, therefore, are not static. They are becoming wider with each advance in multimodal therapy. Clinicians must keep abreast of the results of clinical trials so they can offer their patients the combination of treatments that will preserve function, and produce the smallest number of late complications without jeopardizing survival chances.

Renal cell carcinoma in Japanese children

Renal cell carcinoma in children is extremely rare compared to Wilms tumor. We report on a 7-year-old Japanese boy with left renal cell carcinoma. Since the disease was clinical stage I, nephrectomy with tumor extirpation was performed after a short course of initial chemotherapy had been administered. The patient is free of disease 3 years postoperatively. In a review of the Japanese literature we found 71 reports of renal cell carcinoma in children less than 15 years old. Mean patient age at occurrence was 8.1 years, there were no differences in regard to the sex or the affected side, and the most frequent symptom was the presence of a mass. We stress the early establishment of diagnosis in children with a persistent abdominal mass, hematuria and flank pain, since surgical treatment leads to a favorable prognosis only in the early stage of renal cell carcinoma.

Renal parenchymal carcinoma in children

A series of 14 cases of renal parenchymal carcinoma in patients under 20 years of age is presented and reviewed with the best documented case reports from the literature. Unlike its adult counterpart the tumour has an equal sex ratio and minor trauma frequently precipitates presentation, otherwise its behaviour is similar. The treatment of choice is nephrectomy but, unlike adults, there is evidence to support the value of adjunctive radiotherapy and chemotherapy in the treatment of local spread. Prognosis is particularly worsened by cellular granularity, and vascular or direct extrarenal spread. The 5 year survival rate is 52 per cent.

Cytogenetics of a renal adenocarcinoma in a 2-year-old child

Chromosomal abnormalities in a 2.4-year-old boy with renal adenocarcinoma (Grawitz tumor) are described. Renal adenocarcinoma is extremely rare in childhood, compared with nephroblastoma (Wilms' tumor). In all tumor cells the same 46,XY,t(X;1) (p11.2;q21.2) karyotype was found. This karyotype is compared with the cytogenetic descriptions of renal adenocarcinoma in adults.

Undifferentiated renal cell carcinoma in infancy: report of a case and review of literature

A case of rapidly progressed undifferentiated renal cell carcinoma in a 2 2/12-month-old boy is reported. The histology is characterized by sarcomalike spindle and pleomorphic cells and bizarre giant cells, thus creating many difficulties in the differential diagnosis. The diagnosis of renal cell carcinoma was established on the basis of tubular formation by clear and granular cells observed in a few discrete areas. The literature on renal cell carcinoma occurring under 10 years of age was reviewed, with special attention given to histological typing. It is generally believed that renal cell carcinoma in children is well differentiated, but 2 of 39 cases reviewed were undifferentiated. We conclude that renal cell carcinoma in infants or young children may have an undifferentiated, atypical histological appearance and can progress rapidly. The differential diagnosis from anaplastic Wilms' tumor and sarcomatous tumors of the kidney in children is discussed.

Renal cell carcinoma in childhood and adolescence: a clinical and pathological study of 17 cases

From 1955 through 1984, 17 patients aged 17 years or younger were treated or seen in consultation for renal cell carcinoma at the Children's Hospital and Dana Farber Cancer Institute. There were 11 girls and 6 boys, with an average age at diagnosis of 11 years (range 4 to 17 years). Gross hematuria and abdominal or flank pain were the most common presenting complaints, and in 5 cases there was a history of antecedent trauma. The tumors ranged in size from 2 to 15 cm. (average diameter 7.5 cm.). There were 10 tumors in the left kidney and 7 in the right kidney. Childhood renal cell carcinoma displayed similar gross and microscopic features compared with counterparts in adults. The smallest renal cell carcinoma to metastasize measured 3 cm. in diameter and the pathological features suggested an origin from distal collecting tubules (ducts of Bellini). There were 6 tumor-related deaths (35 per cent over-all mortality) occurring 2 months to 2 years after diagnosis. Eleven children were well, with an average duration of followup of 12 years (range 4 to 27 years). The most important prognostic factor was clinical stage at the time of diagnosis. The presence of renal vascular invasion per se did not appear to be an adverse finding. The most optimal treatment for children with stage I renal cell carcinoma is radical nephrectomy with regional lymphadenectomy. While adjuvant radiation and/or chemotherapy may be used in patients with more advanced stage disease, their efficacy in achieving long-term survival free of relapse or cure is not well defined.