Radiotherapy omitted in the treatment of selected children under 3 years of age with stage III favorable histology Wilms tumor

Treatment of Wilms Tumor in Sub-Saharan Africa: Results of the Second French African Pediatric Oncology Group Study

PURPOSE

Multidisciplinary management of Wilms tumor has been defined through multicenter prospective studies and an average expected patient cure rate of 90%. In sub-Saharan Africa, such studies are uncommon. After the encouraging results of the first Groupe Franco-Africain d'Oncologie Pédiatrique (GFAOP) study, we report the results of the GFAOP-NEPHRO-02 study using an adaptation of the International Society of Paediatric Oncology 2001 protocol.

PATIENTS AND METHODS

From April 1, 2005, to March 31, 2011, seven African units participated in a nonrandomized prospective study. All patients who were referred with a clinical and radiologic diagnosis of renal tumor were screened. Those older than age 6 months and younger than 18 years with a unilateral tumor previously untreated were pre-included and received preoperative chemotherapy. Patients with unfavorable histology or with a tumor other than Wilms, or with a nonresponding stage IV tumor were excluded secondarily.

RESULTS

Three hundred thirteen patients were initially screened. Two hundred fifty-seven patients were pre-included and 169 with histologic confirmation of intermediate-risk nephroblastoma were registered in the study and administered postoperative treatment. Thirty-one percent of patients were classified as stage I, 38% stage II, 24% stage III, and 7% stage IV. Radiotherapy was not available for any stage III patients. Three-year overall survival rate was 72% for all study patients and 73% for those with localized disease.

CONCLUSION

It was possible to conduct sub-Saharan African multicenter therapeutic studies within the framework of GFAOP. Survival results were satisfactory. Improvements in procedure, data collection, and outcome are expected in a new study. Radiotherapy is needed to reduce the relapse rate in patients with stage III disease.

Treatment of nephroblastoma in Africa: results of the first French African pediatric oncology group (GFAOP) study

BACKGROUND

The multidisciplinary management of nephroblastoma has been defined through multicentric prospective studies and an average 90% of patients cured expected. In Africa, such studies are uncommon and results are fragmentary or unknown in most of the countries. We report the results of the GFAOPNEPHRO 01 study using SIOP 2001 protocol approach.

PROCEDURE

From April 1, 2001 to March 31, 2004, 8 African Pilot Units were selected to participate in a nonrandomized prospective study. All patients referred with a clinical and radiological diagnosis of nephroblastoma were registered, those aged over 6 months and less than 18 years with a unilateral tumor not previously treated were included in this study and received preoperative chemotherapy. Patients with unfavorable histology or with a tumor other than Wilms tumor, and those with stage IV tumor and persistent disease after surgery were secondarily excluded.

RESULTS

Of the 229 patients initially registered, 166 were included and finally 133 retained in the study, after surgery. Tumor rupture occurred in 7.5% of the patients. Thirty-five percent were stage I, 22% stage II, 23% stage III, and 18% stage IV. Two-year disease-free survival and 5-year survival are, respectively: 77.9% and 76.7% for localized tumors, 72.7% and 71.6% for all study patients.

CONCLUSIONS

It is possible to conduct African multicentric therapeutic studies within the framework of GFAOP. Results in terms of event-free survival and survival are satisfactory. Improvements with respect to procedure, data collection, and outcome are expected in a new study.

Wilms' tumor: past, present and (possibly) future

Wilms' tumor is one of the successes of pediatric oncology, with an overall cure rate of over 85%, using relatively simple therapies. This excellent outcome has been the result of collaborative efforts among surgeons, pediatricians, pathologists and radiation oncologists. The results that have been achieved in children with Wilms' tumors support the strong value of the multidisciplinary team approach to cancer. The two largest cooperative groups that have studied the optimum treatment for Wilms' tumor are the National Wilms' Tumor Study group in North America and the International Society of Pediatric Oncology, involving European and other countries. The National Wilms' Tumor Study group recommends primary surgery before any adjuvant treatment, whereas the International Society of Pediatric Oncology trials are based on the use of preoperative chemotherapy. The debate on primary chemotherapy versus primary nephrectomy appears to have been overcome, in the sense that the advantages and disadvantages of these two diverse methods have emerged from large and well-performed clinical trials, and comparably low doses of anthracyclines and radiotherapy are now used. Challenges remain in identifying novel molecular, histological and clinical risk factors for stratification of treatment intensity. This could allow a safe reduction in therapy for patients known to have an excellent chance of cure with the current therapy, while identifying, at diagnosis, the minority of children at risk of relapse, who will necessitate more aggressive treatments. Another positive factor is the substantial progress that has been made in the cure for recurrent patients, with long-term survivals shifting from 30 to almost 60% in more recently treated patients with intensive-dose chemotherapy regimens. The combination of lower relapses and higher salvage rates translated into significantly improved overall survival for Wilms' tumor patients as a whole. This review covers current concepts on treatment strategies for Wilms' tumor, with an overview of the results and achievements of the important clinical trials.

Prognostic value of quantifying apoptosis factor expression in favorable histology wilms tumors

Important in the homeostasis of normal tissues, apoptosis can be altered to favor cell survival within tumors. High expression of survivin, an inhibitor of apoptosis, and absence of caspase 8, a pro-apoptotic enzyme, independently correlate with poor outcomes in several tumor types. Favorable histology Wilms tumor has a remarkably high cure rate; as a result, the focus of therapy is now aimed at reducing treatment-related morbidity. With the goal of safely reducing therapy in select subgroups of patients, the authors investigated whether the levels of apoptotic factors in tumors could predict the risk for recurrence. Tumor apoptotic factor levels were surveyed in a case-control study from the National Wilms Tumor Study 5 (NWTS-5) and measured via quantitative real-time RT-PCR. Survivin and caspase 8 levels were surveyed in 92 primary tumor specimens and SMAC, Bid, and CD95 were surveyed in 24 specimens. All four pro-apoptotic factors studied (caspase 8, SMAC, Bid, and CD95) were analyzed individually and in relation to survivin expression. Although survivin mRNA was present at markedly greater levels than in normal kidney, none of the factors assayed independently or as a ratio was associated with stage of disease or risk for tumor recurrence in this group of tumors.

Outcome of patients with stage III or inoperable WT treated on the second United Kingdom WT protocol (UKWT2); a United Kingdom Children's Cancer Study Group (UKCCSG) study

BACKGROUND

The aims of UKWT2 included consolidating the results for stage III patients obtained in UKWT1 and improving the outcome for patients with inoperable tumours by giving vincristine, actinomycin-D and doxorubicin in an intensive schedule (Intensive AVA).

PROCEDURE

The second UK WT trial (UKWT2) ran between July 1986 and September 1991 accruing 448 patients. One hundred and six patients were diagnosed and treated for stage III disease. Six had clear cell sarcoma of the kidney (CCSK) and seven had rhabdoid tumours of the kidney (RTK) and are analysed separately. One other patient was excluded from overall analysis. Ninety-two patients were followed for a median of 115 months. Seventy-five received standard chemotherapy and abdominal radiotherapy according to protocol. Seventeen had stage III disease at immediate nephrectomy, but radiotherapy was omitted by physician choice. Thirty-three patients had inoperable disease at diagnosis and received pre-nephrectomy chemotherapy.

RESULTS

Overall survival (OS) at 4 years for stage III favourable histology (FH) patients receiving abdominal RT was 83% (CI: 73-89). For children with stage III disease in whom RT was omitted the OS was 82% (CI: 59-97) and for inoperable disease 94% (CI: 78-98). The overall and event-free survival (EFS) of children with stage III CCSK was 100% and was achieved with the majority of patients not receiving radiotherapy (CI: 48-100). Three of seven children with RTK are alive EFS and OS 43% (CI: 10-73). For patients treated by abdominal radiotherapy the overall local control rate was 94.4% (CI: 86.4-98.5*%), 96.7% (CI: 88.5-99.6%) for flank RT and 83.3% (51.6-98.0%) for whole abdominal radiotherapy (WRT).

CONCLUSIONS

The outcome for stage III FH disease was similar to that reported for UKWT1 and NWTS-3. The combination of abdominal RT together with 3-drug chemotherapy achieves a high abdominal tumour control rate. Flank RT is probably sufficient for localised tumour rupture. The high cure rates for children in this trial with 'inoperable disease' suggests that treatment should be modified according to their post-chemotherapy stage in order to avoid over-treatment. The high OS for stage III CCSK on this protocol suggests that treatment duration could be curtailed and the role of RT reviewed, though the numbers are small. The prognosis for older children with RTK seems to be better than for younger children although larger studies are required to confirm this.

111 renal neoplasms of childhood: a clinicopathologic study

PURPOSE

The aim of this study was to perform a clinicopathologic evaluation of a single pediatric institution renal tumor series. Most patients were treated within the frame of 3 consecutive SIOP trials, which included preoperative chemotherapy as their main feature.

METHODS

Medical records and diagnoses of 111 patients were reviewed. The association of pathologic features with outcome was investigated by means of the Kaplan-Meier method, the Cox model, and a logistic multivariate analysis. Comparison among different trial results was carried out.

RESULTS

In 98 patients (88%), nephroblastoma was diagnosed, followed by 6 adult-type renal tumors, 3 cystic nephromas, 2 mesoblastic nephromas, and 2 clear cell sarcomas. For nephroblastoma, a statistically significant correlation between grade and both disease-free survival rate and 5-year survival rate, and between stage and overall survival rate was shown. Lymph node involvement, local relapse, nephrogenic rests, and older age at presentation appeared to be less important prognostic factors. Tumor spillage was very sensitive to chemo or radiotherapy. No significant difference in outcome was observed among different trials.

CONCLUSIONS

Wilms' tumor was the most frequent neoplasm and resulted in a 5-year cure rate of 90%. Clinical course was influenced mainly by diffuse anaplasia and, to a minor extent, by lymph node involvement. Because some tumors followed an unpredictable course, it is likely that also other biological factors played a significant role.

The treatment of Wilms' tumour: results of the United Kingdom Children's cancer study group (UKCCSG) second Wilms' tumour study

The aims of the UKW2 study were: (1) to further refine treatment for stage I and II favourable histology (FH) patients; (2) to consolidate the UKW1 results for stage III FH patients; (3) to improve the outlook for patients with inoperable primary tumours and those patients with stage IV and unfavourable histology disease. Treatment consisted of primary nephrectomy, wherever possible, followed by chemotherapy and radiotherapy, as dictated by stage and histology. Treatment was refined successfully for stage I and II FH patients. The 4-year event-free survival for these two groups was 94% and 91%, respectively. Stage III FH patients had a 4-year event free survival of 84%. The outlook for patients with clear cell sarcoma of the kidney is as good as for patients with favourable histology, whilst that for patients with anaplastic or rhabdoid variants remains poor. The outlook for the majority of children with Wilms' tumour is now excellent.