Responsiveness of chemotherapy based on the histological type and Wilms' tumor suppressor gene mutation in bilateral Wilms' tumor

A pelvic mass 21 years after a Wilms tumour: late recurrence or new tumour?

INTRODUCTION

Late Wilms tumour (WT) recurrences are rare events with poorly understood pathogenesis. They could be induced by previous chemo- and radiotherapy regimens, which can also prompt a rhabdomyomatous differentiation. Prostatic embryonal rhabdomyosarcoma (PER) is an extremely rare disease in adults, with an aggressive behaviour and abysmal prognosis. Radio-induced PER have been described.

CASE DESCRIPTION

We report the case of a 29 years old man, with a history of WT, diagnosed with a symptomatic prostatic mass. Blastemic elements were shown at the transrectal biopsy, suggesting the possibility of a late WT recurrence. After laparoscopic resection, an unexpected pathologic diagnosis was reached: PER.

CONCLUSION

We retrace and analyse the diagnostic and therapeutic path of the case that represents a mixture of two different conditions which might be unrelated or intertwined in a causal relationship. Among the differential diagnosis of a prostatic mass, the possibility of a prostatic sarcoma should not be overlooked, in presence of blastemic elements, even in a patient with a WT history.

Chemotherapy and terminal skeletal muscle differentiation in WT1-mutant Wilms tumors

Wilms tumors (WT) with WT1 mutations do not respond well to preoperative chemotherapy by volume reduction, suggesting resistance to chemotherapy. The histologic pattern of this tumor subtype indicates an intrinsic mesenchymal differentiation potential. Currently, it is unknown whether cytotoxic treatments can induce a terminal differentiation state as a direct comparison of untreated and chemotherapy-treated tumor samples has not been reported so far. We conducted gene expression profiling of 11 chemotherapy and seven untreated WT1-mutant Wilms tumors and analyzed up- and down-regulated genes with bioinformatic methods. Cell culture experiments were performed from primary Wilms tumors and genetic alterations in WT1 and CTNNB1 analyzed. Chemotherapy induced MYF6 165-fold and several MYL and MYH genes more than 20-fold and repressed many genes from cell cycle process networks. Viable tumor cells could be cultivated when patients received less than 8 weeks of chemotherapy but not in two cases with longer treatments. In one case, viable cells could be extracted from a lung metastasis occurring after 6 months of intensive chemotherapy and radiation. Comparison of primary tumor and metastasis cells from the same patient revealed up-regulation of RELN and TBX2, TBX4 and TBX5 genes and down-regulation of several HOXD genes. Our analyses demonstrate that >8 weeks of chemotherapy can induce terminal myogenic differentiation in WT1-mutant tumors, but this is not associated with volume reduction. The time needed for all tumor cells to achieve the terminal differentiation state needs to be evaluated. In contrast, prolonged treatments can result in genetic alterations leading to resistance.

WT1 Mutation in Childhood Cancer

In this chapter, the role of WT1 in childhood cancer is discussed, using the key examples Wilms' tumor, desmoplastic small round cell of childhood, and leukemia. The role of WT1 in each disease is described and mirrored to the role of WT1 in normal development.

Nephroblastoma is a success of paediatric oncologic therapy. How further can we go?: Results of a cyto-histologic correlation study

Nephroblastoma is a success of paediatric oncologic therapy, yet, there are still some cases where favourable response to preoperative chemotherapy is not achieved. Fine needle biopsy has the role of diagnostic confirmation and, idyllically of predicting a response to preoperative chemotherapy. To advance in this aim, we retrieved a total of 14 nephroblastomas, (seven male patients and seven female with a mean age of 44.4 months), diagnosed in our department by fine needle biopsy and submitted afterward to chemotherapy and nephrectomy, in the last 10 years. Correlation between cytologic features, (morphology, cell death, and proliferation (Ki-67 labelling index), and post chemotherapy tumour evaluation was done. Cytologic pattern per se was not predictive of histologic tumour classification (P = 0.6061). We did not find any correlation between the percentage of necrosis and apoptosis (P = 0.682) in cytologic smears and histologic regressive changes but when both these two criteria coexisted in cytologic blastemal component of nephroblastomas, this fact seemed to lead to a favourable response of the tumour to chemotherapy. When evaluation of Ki-67 labelling index was done in the blastematous component present in the smears, divergent results were obtained. The small number of cases prevented any firm conclusions. By summing up, our results support the idea that there are probably two types of blastema in nephroblastoma with different "suicide" potential and chemotherapeutic response. Further studies should be performed to stratify the influence of necrosis, apoptosis, and proliferation in chemosensivity of nephroblastomas.

Late relapsing Wilms tumor with rhabdomyomatous differentiation

The authors report a patient with abdominally relapsed Wilms tumor with rhabdomyomatous differentiation leading to renal failure and death 9 years after the initial diagnosis. The patient was treated with intensive chemotherapy because of inoperable tumor but no response was obtained. The prognosis of children with Wilms tumor relapsed in abdomen and in previously irradiated fields is poor and intensive chemotherapy protocols for differentiated tumors after chemotherapy will increase the risk of complications without obvious benefit.

Clinical relevance of mutations in the Wilms tumor suppressor 1 gene WT1 and the cadherin-associated protein beta1 gene CTNNB1 for patients with Wilms tumors: results of long-term surveillance of 71 patients from International Society of Pediatric Oncology Study 9/Society for Pediatric Oncology

BACKGROUND

Mutations in the Wilms tumor (WT) suppressor 1 gene (WT1) and the cadherin-associated protein beta1 gene (CTNNB1) are found predominantly in stromal type WT, defining a genetic subgroup. The clinical relevance of these mutations remains to be determined.

METHODS

A long-term follow-up study was performed for 71 patients (International Society of Pediatric Oncology Study 9/Society for Pediatric Oncology; n = 77 tumors) with known molecular genetic status. Eight patients had bilateral disease, including 2 patients with a WT in both kidneys and 5 patients with a WT in 1 kidney and nephrogenic rests (NRs) in the other kidney. The response to preoperative chemotherapy, relapses, metastases, metachronous tumor development, and deaths were evaluated with a median follow-up of 12 years and 4 months.

RESULTS

Nineteen patients (n = 24 tumors) had WT1 mutations, and 16 were constitutional mutations. Three patients with germline mutations had second tumor events: Two patients developed a WT in the kidney with NRs 3 years and 11 years after the first tumor; and 1 patient developed second tumors after 2 years, 1 in the kidney with a previous WT and 1 in the kidney with a previous NR. Eighteen of the WT1 mutant tumors were analyzed for CTNNB1 mutations, and all had mutations. A poor volumetric response (progression and <50% reduction) was observed in all patients who had tumors with a WT1 mutation and in 23 of 52 nonmutant tumors.

CONCLUSIONS

Patients with WT1 germline mutations had an increased risk for bilateral disease and second tumor events. Therefore, the authors concluded that tumor surveillance until adulthood should be considered. Although tumors with both WT1 and CTNNB1 mutations had a poor volumetric response, there was no significant difference in overall survival in this cohort of patients with and without WT1 mutations.

Rhabdomyoblastic pulmonary lesions in a patient with Wilms tumor: choristomas or metastases?

New lesions that occur while patients are receiving treatment for malignant tumors may represent not only difficulties in arriving at the correct diagnosis, but also impact on subsequent therapeutic options. We encountered a patient developing new pulmonary lesions during and after receiving treatment for Stage II Wilms tumor (WT). The presence of mature rhabdomyoblasts in multiple biopsy specimens allowed rational decisions to be made regarding subsequent therapy. This and other published experiences suggest that patients with WT may develop choristomas or have tumors, which undergo cytodifferentiation. Methodologies are now available allowing differentiation of these two processes.

Survival in nephroblastoma treated according to the trial and study SIOP-9/GPOH with respect to relapse and morbidity

BACKGROUND

Recent Wilms' tumor (WT) trials and studies have tried to determine the minimal therapy needed for cure. The goal was survival without morbidity.

PATIENTS AND METHODS

From January 1989 to March 1994 the German Society of Pediatric Oncology and Hematology registered 440 patients (median age 2.9 years; 231 male, 209 female) with WTs (preoperative chemotherapy 362) for therapy according to the International Society of Pediatric Oncology Trial and Study 9. Therapy for relapse depended on site of relapse and therapy already received. Follow-up included inquiries for morbidity. Prognostic factors for relapse and death were evaluated.

RESULTS

Five-year survival of WTs was 89.5%; 98.2% (385 of 392) of survivors had a follow-up of 5 years (range 0.8-12.6; median 8). In non-anaplastic WTs, young age (<2 years) was of significance (P = 0.026) for a better survival. Non-anaplastic WTs (407 patients) had a 5-year survival of 92.3%, versus 48.5% in anaplastic WTs (33 patients), and a 5-year relapse-free survival of 87.6% versus 42.4%. Survival after relapse was significantly worse for anaplastic than for non-anaplastic WTs (residual 3-year survival 11.8% versus 54.3%; P <0.0001). In preoperatively treated WTs, anaplasia was a strong prognostic factor for death [relative risk (RR) 4.7], followed by poor response to preoperative therapy (RR 3.6), stage IV (RR 3.2) and abdominal stage III (RR 2.2). Low abdominal stages (<III) dominated (280 versus 82). In the 334 unilateral stage I-IV WTs (median age 3.2 years), diffuse anaplasia (21 patients) had a 5-year relapse-free survival of 38.1%, versus 58.4% in blastemal WTs (25 patients); survival was 42.9% in diffuse anaplasia versus 84% in blastemal WTs. None of 46 patients (median age 1.9 years; 91.3% stages I or II) with differentiated WTs (nine epithelial, 37 stromal) relapsed despite their non-response; two died (one therapy related, one due to bilaterization). In the 25 non-anaplastic bilateral WTs, differentiated cases (one epithelial, eight stromal, 33.3% abdominal stage III) were more frequent (P = 0.048) than in unilateral WTs (one stromal, abdominal stage III relapsed). In all, 52.9% of the 5-year survivors had received adriamycin (250-400 mg/m(2)), 25.7% radiation, 6.4% ifosfamide (24-30 g/m(2)) and 6.7% carboplatin plus etoposide. Abnormal parameters according to the National Cancer Institute score were seen in 18.9% during follow-up, but only 6.4% were treated for morbidity at the end of follow-up. Three WTs developed renal failure due to Drash syndrome, but none due to tumor therapy. After adriamycin 1.9% of WTs (9% of those receiving 400 mg/m(2)) required therapy for cardiac toxicity.

CONCLUSIONS

Initial therapy should be more individualized, taking the above risk groups (age in non-anaplastic WTs, poor response, anaplasia, etc.) into account, as morbidity even after relapse therapy with ifosfamide, carboplatin and etoposide was not high. Milder therapy in low stages of differentiated and of well responding WTs should be tested.