Veno-occlusive disease in pediatric patients affected by Wilms tumor

Severe Hepatopathy in National Wilms Tumor Studies 3-5: Prevalence, Clinical Features, and Outcomes After Reintroduction of Chemotherapy

PURPOSE

The safety of reintroducing chemotherapy in the pediatric renal tumor setting after severe hepatopathy (SH), including sinusoidal obstruction syndrome (SOS), is uncertain. We describe the incidence, severity, outcomes, and impact on subsequent treatment for patients with SH from National Wilms Tumor Study (NWTS) protocols 3-5.

PATIENTS AND METHODS

Archived charts for patients enrolled on NWTS 3-5 who met study inclusion criteria for SH by using established hepatopathy grading scales and clinical criteria were reviewed for demographics, tumor characteristics, radio- and chemotherapy details, SH-related dose modifications, and oncologic outcomes. Genomic analysis for candidate polymorphisms associated with SH was performed in 14 patients.

RESULTS

Seventy-one of 8,862 patients (0.8%) met study inclusion criteria. The median time from therapy initiation to SH was 51 days (range, 2-293 days). Sixty percent received radiotherapy, and 56% had right-sided tumors. Grade 1-4 thrombocytopenia was noted in 70% at initial occurrence of SH (median 22,000/microliter). Among 69 of 71 children with SH occurring before the end of therapy (EOT) and post-SH treatment information available, chemotherapy was delayed posthepatopathy for 65% (69% of these at a reduced dose), continued without delay for 20% (57% of these at reduced dose), and stopped completely for 15% (4 of 10 of whom died of SH). Overall, 42% of patients with dose reductions achieved full dose by EOT. The five-year post-SH event-free survival for patients who continued therapy was 89% (95% CI, 81 to 98), with no significant differences by whether delay or dose reduction occurred. We identified no SH-associated pharmacogenomic polymorphism.

CONCLUSION

The incidence of SH on NWTS 3-5 was low; many had associated severe thrombocytopenia. Careful reintroduction of chemotherapy appeared to be feasible for the majority of patients who developed severe chemotherapy- and/or radiotherapy-induced liver toxicity.

Sinusoidal Obstruction Syndrome of the Liver Associated With 6-Mercaptopurine During Maintenance in a Child With T-cell Acute Lymphoblastic Leukemia

Sinusoidal obstruction syndrome (SOS) of the liver is a complication of chemotherapy most often encountered with hematopoietic stem cell transplant due to high-dose conditioning regimens, but it can also occur with regimens outside of the transplant setting. Mild-to-moderate SOS is a well-described 6-thioguanine toxicity; however, it has rarely been reported as secondary to 6-mercaptopurine, a related thiopurine. This report details a case of a 10-year-old male with T-cell acute lymphoblastic leukemia who developed severe SOS during maintenance therapy with 6-mercaptopurine, and a review of the related literature.

Treatment of Sinusoidal Obstruction Syndrome With Defibrotide in Pediatric Cancer Patients Following Nontransplant-associated Chemotherapy: A Case Report and Review of the Literature

Sinusoidal obstruction syndrome (SOS), formerly veno-occlusive disease (VOD), in pediatric cancer patients often presents as a complication of hematopoietic stem cell transplantation, and less commonly secondary to nontransplant-associated chemotherapy. Therapy with defibrotide is well-described as standard care for transplant-associated SOS/VOD, but the treatment of nontransplant-associated SOS/VOD is less clear. We report a 3-year-old with relapsed Wilms tumor and recurrent SOS/VOD, with successful use of defibrotide during chemotherapy. A review of pediatric cancer patients with nontransplant-associated SOS/VOD treated with defibrotide revealed 83 patients, and 66 were in remission. This review supports early treatment with defibrotide in patients with nontransplant-associated SOS/VOD.

Introduction of new pediatric EBMT criteria for VOD diagnosis: is it time-saving or money-wasting? : Prospective evaluation of pediatric EBMT criteria for VOD

Hepatic veno-occlusive disease (VOD) is a potentially fatal complication following hematopoietic stem cell transplantation (HSCT). We evaluated in prospective analysis the usefulness of the pediatric EBMT criteria for VOD diagnosis and their presumable impact on cost effectiveness and patients' outcome. Study included all 282 HSCT procedures performed in Department of Pediatric Hematology/Oncology and BMT in Wrocław between January 2016 and March 2019. Data were compared with previous VOD research conducted in our center before year 2016. Twenty-five (8.9%) patients (median age 3.5 years) were diagnosed with VOD. Duration of defibrotide (DF) administration varied from 4 to 34 days (median: 16.5), with 96% response rate. Overall survival was 88%. If applying Baltimore and modified Seattle criteria, VOD incidence was 2.13% and 5.7%, respectively. Median diagnosis delay based on modified Seattle criteria was 3 days. Before 2016, VOD incidence was 4.9%, with 74% DF response rate (p = 0.033) and 56.2% OS (p = 0.008). After implementing new criteria length of hospitalization for VOD patients decreased by median of 12 days (p = 0.009). Earlier VOD diagnosis, facilitated by EBMT criteria, resulting in implementing immediate treatment significantly improved patients' outcome. Furthermore, it allows shortening of DF administration and minimizes length of hospital stay.

Modified diagnostic criteria, grading classification and newly elucidated pathophysiology of hepatic SOS/VOD after haematopoietic cell transplantation

Sinusoidal obstruction syndrome (SOS), previously known as hepatic veno-occlusive disease (VOD), remains a multi-organ system complication following haematopoietic cell transplantation (HCT). When SOS/VOD is accompanied by multi-organ dysfunction, overall mortality rates remain >80%. However, the definitions related to the diagnosis and grading of SOS/VOD after HCT are almost 25 years old and require new and contemporary modifications. Importantly, the pathophysiology of SOS/VOD, including the contribution of dysregulated inflammatory and coagulation cascades as well as the critical importance of liver and vascular derived endothelial dysfunction, have been elucidated. Here we summarise new information on pathogenesis of SOS/VOD; identify modifiable and unmodifiable risk factors for disease development; propose novel, contemporary and panel opinion-based diagnostic criteria and an innovative organ-based method of SOS/VOD grading classification; and review current approaches for prophylaxis and treatment of SOS/VOD. This review will hopefully illuminate pathways responsible for drug-induced liver injury and manifestations of disease, sharpen awareness of risk for disease development and enhance the timely and correct diagnosis of SOS/VOD post-HCT.

PAI-1 and protein C as early markers of veno-occlusive disease in patients treated for Wilms tumor

BACKGROUND

Hepatic veno-occlusive (VOD) disease has been described in hematopoietic stem cell transplantation (HSCT), solid tumors, and acute lymphoblastic leukemia. The incidence of VOD in Wilms tumor (WT) ranges from 1.2% to 8%. The diagnosis of VOD is clinical, and there are no validated laboratory biomarkers.

PROCEDURE

We prospectively evaluated the specificity and sensitivity of plasminogen-activator inhibitor-1 (PAI-1) and protein C as diagnostic markers of VOD in WT patients. Fifty patients treated from 2008 to 2016 for WT were eligible. VOD was diagnosed according to modified Seattle criteria and retrospectively reclassified according to the recently published criteria for VOD in pediatric HSCT patients.

RESULTS

VOD occurred in 6 of 50 patients (12%) after 20 to 97 days from starting chemotherapy. The average duration of VOD was 10 days (range, 4-13 days). PAI-1 levels were elevated in all VOD patients, while a decrease in protein C levels was observed in 33% of patients with VOD. PAI-1 antigen (Ag) values ≥ 26.4 ng/mL demonstrated high sensitivity and specificity for the clinical diagnosis of VOD with sensitivity 100%, specificity 93%; whereas protein C levels below 34.5% had sensitivity 67%, specificity 100%. Both PAI-1 and protein C had an high negative predictive value: PAI-1 Ag 100%; protein C 95%.

CONCLUSIONS

PAI-1 Ag and protein C have good sensitivity and specificity for the diagnosis of VOD in WT patients. Their high negative predictive value can be used in the differential diagnosis of liver toxicity, especially in VOD episodes with absent or delayed hyperbilirubinemia.

Investigating the dysfunctional pathogenesis of Wilms' tumor through a multidimensional integration strategy

Background

Wilms' tumor (WT) is a common kidney tumor in early childhood which is characterized by multiple congenital anomalies and syndromes. With the continuous improvement of medical standards, the cure rate and survival period of WT have increased. However, its molecular mechanism is still elusive.

Methods

A comprehensive multidimensional integration strategy was used to comprehensively analyze the mechanisms of WT.

Results

By integrating the potential pathogenic genes of kidney cancer and performing co-expression analysis on the disease-related genes, 23 functional modules were obtained. All the genes were differentially expressed in WT, and were mainly involved in many biological processes and signaling pathways, such as Wnt/β-catenin, mTOR/ERK and calcineurin. Additionally, based on the relationship between transcriptional and post-transcriptional regulatory systems, in functional modules, transcription factors (TFs) including STAT3, HDAC1 and SP1 as well as non-coding RNAs (ncRNAs) such as miR-335-5p, miR-21-5p and TUG1 were identified. Finally, potential drugs for these multifactor regulated dysfunctional modules which may have certain pharmacological or toxicological effects on WT such as cisplatin, sorafenib, and zinc were predicted.

Conclusions

A multidimensional dysfunction mechanism, involving disease-related genes, TFs and ncRNAs was revealed in the pathogenesis of WT. Functional modules were used to predict potential drugs which can be used in personalized therapy and drug delivery. This study explored the pathogenesis of WT from a new perspective, and provides new candidate targets and therapeutic drugs for improving the cure rate of WT.

"Pre-emptive strike"-the case for early treatment of hepatic sinusoidal obstruction syndrome with defibrotide

The initial signs of hepatic sinusoidal obstruction syndrome (HSOS) can be challenging to recognize in children, especially outside the hematopoietic stem cell transplantation setting. To assist clinicians to promptly identify HSOS, the European Society for Blood and Marrow Transplantation has proposed pediatric HSOS diagnostic criteria which emphasize unexplained consumptive and transfusion-refractory thrombocytopenia. To highlight the importance of these "bellwether" early signs of HSOS and the efficacy of pre-emptive treatment with defibrotide, we describe the case of a child with a right 11th rib primitive neuroectodermal tumor who developed HSOS following focal radiotherapy and actinomycin-D treatment.

New insights into sinusoidal obstruction syndrome

BACKGROUND

Entry criteria included patients who developed sinusoidal obstruction syndrome (SOS) at a single centre from January 2000 to December 2011. Patients who underwent haemopoietic stem cell transplantation or actinomicyn-based chemotherapy for nephroblastoma were selected. The study group comprised five patients with SOS who were compared with a control group of seven patients without SOS.

AIM

To study the relationships between endothelial extracellular vesicles (EV) and plasminogen-activator inhibitor type 1(PAI-1) to assess their modification in the early phase of SOS.

METHODS

Consecutive blood samples were tested for cell-derived EV, PAI-1 and coagulation parameters. Any statistically significant correlation between all datasets was searched.

RESULTS

Antithrombin level and platelet count were statistically significantly reduced in SOS patients, suggesting a consumption status. PAI-1:Ag and PAI-1:act showed an inverse relationship with platelet counts (coef. -0.034, SE = 0.016; P = 0.041 and -0.052, SE = 0.019; P = 0.011 respectively). During follow up, PAI-1:Ag was inversely related to EV CD144+ (coef. -0.261, SE = 0.094; P = 0.007) and antithrombin (coef -0.509, SE = 0.175; P = 0.005). PAI-1:act showed an inverse association with EV CD144+ (coef.-0.251, SE = 0.121; P = 0.043), EV CD31+/CD41+ (coef. -0.004, SE = 0.002; P = 0.026) and antithrombin (coef. -0.470, SE = 0.220; P = 0.038). EV generated by rupture of gap junctions (EV CD144+) were increased in SOS patients and also showed a change over time.

CONCLUSION

This study demonstrates the existence of an ongoing procoagulant and hypofibrinolytic status in SOS, indicating a possible role for anticoagulant therapy. Moreover, these findings suggest a role for EV CD 144+, either alone or in combination with PAI-1, as a new biomarker for SOS.

Venoocclusive disease due to chemotherapy for pediatric acute lymphoblastic leukemia is associated with increased levels of plasminogen-activator inhibitor-1

We describe three cases of sinusoidal obstruction syndrome/venoocclusive disease (SOS) in pediatric patients with acute lymphoblastic leukemia (ALL). All three episodes occurred during or just after the induction or reinduction phase of treatment based on prednisone/dexamethasone, vincristine, daunorubicin, and pegylated-l-asparaginase. SOS episodes were categorized as mild/moderate and resolved in 7, 10, and 16 days using supportive measures or defibrotide therapy. In all three episodes, the clinical diagnosis of SOS was associated with a significant increase in plasminogen-activator inhibitor-1 (PAI-1) that reduced with patient clinical improvement. PAI-1 warrants study as a diagnostic marker for SOS in ALL.

Diagnosis and severity criteria for sinusoidal obstruction syndrome/veno-occlusive disease in pediatric patients: a new classification from the European society for blood and marrow transplantation

The advances in hematopoietic cell transplantation (HCT) over the last decade have led to a transplant-related mortality below 15%. Hepatic sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a life-threatening complication of HCT that belongs to a group of diseases increasingly identified as transplant-related, systemic endothelial diseases. In most cases, SOS/VOD resolves within weeks; however, severe SOS/VOD results in multi-organ dysfunction/failure with a mortality rate >80%. A timely diagnosis of SOS/VOD is of critical importance, given the availability of therapeutic options with favorable tolerability. Current diagnostic criteria are used for adults and children. However, over the last decade it has become clear that SOS/VOD is significantly different between the age groups in terms of incidence, genetic predisposition, clinical presentation, prevention, treatment and outcome. Improved understanding of SOS/VOD and the availability of effective treatment questions the use of the Baltimore and Seattle criteria for diagnosing SOS/VOD in children. The aim of this position paper is to propose new diagnostic and severity criteria for SOS/VOD in children on behalf of the European Society for Blood and Marrow Transplantation.

Sinusoidal Obstruction Syndrome during Treatment for Wilms' Tumor: A Life-threatening Complication

Context:

Survival rates exceed 90% in Wilms' tumor (WT). Actinomycin-D (ACT-D) which is indispensable in the management of WT is associated with the development of sinusoidal obstruction syndrome (SOS), a potentially fatal complication.

Aims:

The aim is to study the presentation, management, and outcome of SOS complicating ACT-D administration in WT.

Settings and Design:

Retrospective file review conducted in a Pediatric Hematology-Oncology unit.

Materials and Methods:

Patients diagnosed and treated for WT from January 2012 to December 2015 were analyzed. SOS was diagnosed clinically, based on McDonalds criteria, requiring two of the following: jaundice, hepatomegaly and/or right upper quadrant pain, weight gain with or without ascites.

Results:

Of 104 patients treated, SOS occurred in 5 (4.8%). Age: 6 months to 5 years, 3 were girls. Tumor involved left kidney in 3, right in 1 and a horseshoe kidney in 1. Histopathology was consistent with WT in 4 and clear cell sarcoma kidney in 1. One had pulmonary metastases. Three developed SOS preoperatively and two during adjuvant chemotherapy. None received radiotherapy. Clinical manifestations comprised of jaundice, hepatomegaly, ascites/weight gain, respiratory distress, hypotension, and encephalopathy. Laboratory findings included thrombocytopenia, elevated serum transaminases, and coagulopathy. Treatment included fluid restriction, broad spectrum antibiotics, and transfusional support. Two children received N-acetyl cysteine infusion. Defibrotide was administered to two patients. Four recovered and one succumbed to multi-organ failure. Two patients were safely re-challenged with 50% doses of ACT-D.

Conclusions:

SOS is a clinical diagnosis. Systematic supportive care can enable complete recovery. Under close monitoring, re-challenge of ACT-D can be performed in gradually escalating doses.

Defibrotide for children and adults with hepatic veno-occlusive disease post hematopoietic cell transplantation

Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a complication that is typically associated with conditioning for hematopoietic stem cell transplantation (HSCT). In patients with concomitant multi-organ dysfunction, mortality may be >80%. Recently, the European Society for Blood and Marrow Transplantation established separate criteria for diagnosis and severity of VOD/SOS for adults and children, to better reflect current understanding of the disease. Areas covered: This review provides an overview of post-HSCT hepatic VOD/SOS and defibrotide, including its pharmacological, clinical, and regulatory profile. In children and adults following HSCT, defibrotide is approved for the treatment of hepatic VOD/SOS with concomitant renal or pulmonary dysfunction in the United States and for the treatment of severe hepatic VOD/SOS in the European Union. Day +100 survival rates with defibrotide are superior to those of historical controls receiving best supportive care only, and safety profiles are similar. Expert commentary: Defibrotide appears to act through multiple mechanisms to restore thrombo-fibrinolytic balance and protect endothelial cells, and there are promising data on the use of defibrotide for VOD/SOS prophylaxis in high-risk children undergoing HSCT. An ongoing randomized controlled trial in children and adults will better assess the clinical value of defibrotide as a preventive medication.

Sinusoidal Obstruction Syndrome During Chemotherapy of Pediatric Cancers and its Successful Management With Defibrotide

Sinusoidal obstruction syndrome (SOS) is a life-threatening complication generally occurring after hematopoietic stem cell transplantation. SOS after standard dose chemotherapy in malignancies is rare. Between the year 1995 and 2016, 414 patients were diagnosed with acute lymphoblastic leukemia and 113 patients were diagnosed with Wilms tumor in our institution. Among these patients, 4 patients with acute lymphoblastic leukemia (0.96%) and 2 patients with Wilms tumor (1.7%) developed SOS during treatment. SOS behaves like a local disseminated intravascular coagulation. Defibrotide has proved to be effective in SOS. In this article, we report our experience with defibrotide in SOS.

Imaging of acute and subacute toxicities of cancer therapy in children

Effective cancer therapies have resulted in significant improvement in survival. However, treatment-related acute and subacute complications are a cause of significant morbidity and mortality. Effects of cancer therapy in children can be seen early in the survival period or later in life in almost all organ systems of the body. Many of these conditions are evaluated by imaging and some are diagnosed based on characteristic imaging features. This article aims to discuss acute and subacute toxicities of cancer therapy in children involving multiple organ systems, pulmonary, gastrointestinal, hepatobiliary, genitourinary and musculoskeletal systems with emphasis on those in which imaging plays a role in diagnosis or management. We also discuss the role of imaging and choice of imaging modalities in these conditions.

Sinusoidal obstruction syndrome (hepatic veno-occlusive disease)

Hepatic sinusoidal obstruction syndrome (SOS) is an obliterative venulitis of the terminal hepatic venules, which in its more severe forms imparts a high risk of mortality. SOS, also known as veno-occlusive disease (VOD), occurs as a result of cytoreductive therapy prior to hematopoietic stem cell transplantation (HSCT), following oxaliplatin-containing adjuvant or neoadjuvant chemotherapy for colorectal carcinoma metastatic to the liver and treated by partial hepatectomy, in patients taking pyrrolizidine alkaloid-containing herbal remedies, and in other particular settings such as the autosomal recessive condition of veno-occlusive disease with immunodeficiency (VODI). A central pathogenic event is toxic destruction of hepatic sinusoidal endothelial cells (SEC), with sloughing and downstream occlusion of terminal hepatic venules. Contributing factors are SEC glutathione depletion, nitric oxide depletion, increased intrahepatic expression of matrix metalloproteinases and vascular endothelial growth factor (VEGF), and activation of clotting factors. The clinical presentation of SOS includes jaundice, development of right upper-quadrant pain and tender hepatomegaly, ascites, and unexplained weight gain. Owing to the potentially critical condition of these patients, transjugular biopsy may be the preferred route for liver biopsy to exclude other potential causes of liver dysfunction and to establish a diagnosis of SOS. Treatment includes rigorous fluid management so as to avoid excessive fluid overload while avoiding too rapid diuresis or pericentesis, potential use of pharmaceutics such as defibrotide, coagulolytic agents, or methylprednisolone, and liver transplantation. Proposed strategies for prevention and prophylaxis include reduced-intensity conditioning radiation for HSCT, treatment with ursodeoxycholic acid, and inclusion of bevacizumab with oxaliplatin-based chemotherapeutic regimes. While significant progress has been made in understanding the pathogenesis of SOS and in mitigating against its adverse outcomes, this condition remains a serious complication of a selective group of medical treatments.

Non-activated protein C rescue treatment in Wilms tumour associated hepatic sinusoidal obstructive syndrome

Hepatic sinusoidal obstructive syndrome (HSOS) is a frequent complication in patients undergoing haematopoietic stem cell transplant (HSCT), and more rarely, in paediatric patients receiving conventional chemotherapy for solid tumours. Its diagnosis relies on a combination of clinical signs and symptoms such as hepatomegaly, jaundice, weight gain and fluid retention. HSOS treatment is primarily based on supportive care and anti-fibrinolytic agents. Here we report two patients affected by Wilms tumour who developed life-threatening HSOS that failed to respond to conventional treatment. Both patients recovered after receiving aggressive supportive treatment that included administration of non-activated protein C (Ceprotin®--Baxter).

Hepatic sinusoidal obstruction syndrome during chemotherapy for childhood medulloblastoma: report of a case and review of the literature

Hepatic sinusoidal obstruction syndrome (HSOS), also known as veno-occlusive disease, is a well-recognized toxic complication after autologous and allogeneic hematopoietic stem cell transplant, during treatment of Wilms tumor and rhabdomyosarcoma associated with actinomycin-D, and during acute lymphoblastic leukemia therapy due to oral 6-thioguanine. However, its occurrence in the context of chemotherapy regimens for other childhood malignancies is rare. We report a 5-year-old girl with high-risk anaplastic medulloblastoma, who developed severe HSOS during her second cycle of maintenance chemotherapy, consisting of vincristine, cisplatin, and cyclophosphamide. She was treated with defibrotide with complete resolution of the HSOS. These findings and a review of the literature, highlight the occurrence of HSOS in children outside the established settings of hematopoietic stem cell transplantation, Wilms tumor, rhabdomyosarcoma, and acute lymphoblastic leukemia.

Defibrotide: properties and clinical use of an old/new drug

The drug named defibrotide (DFT) has been studied for many years. It has been shown to possess many activities: profibrinolytic, antithrombotic-thrombolytic, antiischemic (heart, liver, kidney, skin, brain), antishock, antiatherosclerotic, antirejection and anti-angiogenic. The previously displayed activities, as antithrombotic, profibrinolytic and anti-inflammatory, suggested its use in vascular disorders, as in the treatment of peripheral obliterative arterial disease and in thrombophlebitis. Some years after, the use of DFT in hepatic veno-occlusive disease has been also proposed. Even if DFT was considered for long time a multi-target drug, now it could be considered on the whole as a drug able to protect endothelium against activation. The present work reviews the more important experimental and clinical studies performed to detect DFT effects.

Hepatopathy-thrombocytopenia syndrome after actinomycin-D therapy: treatment with defibrotide

We report a case of administration compassionate use defibrotide in a 13-year-old girl with Sinusoidal Obstructive Syndrome and thrombocytopenia, also known as Hepatopathy--Thrombocytopenia Syndrome (HTS) during chemotherapy for Wilms' tumor.

Drug safety evaluation of defibrotide

INTRODUCTION

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a potentially life-threatening complication of chemotherapeutic conditioning used in preparation for hematopoietic stem-cell transplantation (SCT). Defibrotide (DF) has been shown in Phase II and III trials to improve complete response in patients with severe VOD (sVOD). None of the articles, to date, provide a comprehensive review of the safety of DF in VOD and/or a range of other conditions.

AREAS COVERED

This article reviews current clinical findings on DF, primarily in terms of safety for use in treatment and prophylaxis of VOD, and relevant safety data for its use in other diseases. The literature review was conducted using a PubMed search with the fixed term 'defibrotide' in combination with ≥ 1 of 'safety', 'veno-occlusive disease' (with and without 'treatment', 'prevention'), 'oncology', 'myeloma', 'microangiopathy', 'anti-thrombotic' and 'peripheral vascular disorder'. Related articles from the EBMT and ASH conference websites were also included.

EXPERT OPINION

DF was well tolerated in majority of the studies. The safety profile of DF is largely favourable with toxicities comparable to control populations in the setting of SCT complicated by sVOD.

Preoperative chemotherapy with doxorubicin in Wilms tumor

BACKGROUND

Vincristine and actinomycin-D have long been used as the preoperative chemotherapy before nephrectomy in patients with Wilms tumor (WT). Actinomycin-D is not readily found in Turkey, and delay in treatment, occurring basically from commercial and marketing problems, prompted us to administer alternatives such as doxorubicin, another antitumor antibiotic available in Turkey, to our newly diagnosed patients with WT.

PROCEDURE

Between November 2009 and January 2011, 12 consecutive patients with WT were included in the study. Preoperative chemotherapy consisted of vincristine (1.4 mg/m, days 1, 8, 15, and 22) and doxorubicin (20 mg/m, 1 to 3 d).

RESULTS

All renal tumors showed shrinkage drastically after 4 weeks of preoperative chemotherapy. Surgery of all the patients was uneventful and without any complications. At the end of the median follow-up time of 8 months (range, 6 to 17 mo), all patients are in remission without a sign of the disease.

CONCLUSIONS

Preoperative chemotherapy consisting of vincristine and doxorubicin seems to be successful as a preoperative treatment in achieving shrinkage and reducing the risk of surgical complications. On the basis of the promising results in our study, it is worth administering a similar regimen with further follow-up in larger populations.

Dactinomycin-induced Hepatic Sinusoidal Obstruction Syndrome Responding to Treatment with N-acetylcysteine

Hepatic sinusoidal obstruction syndrome is commonly described in pediatric oncology as a complication of chemotherapy. It has also been occasionally reported in adult cancer patients. Treatment is largely supportive with fluid restriction. A 16-month-old girl with stage II Wilms tumor receiving post-nephrectomy chemotherapy with dactinomycin and vincristine developed hepatic sinusoidal obstruction syndrome with painful hepatomegaly, ascites with significant weight gain, grossly deranged liver function, severe thrombocytopenia, and reversal of blood flow in the portal vein on Doppler sonography. Treatment with N-acetylcysteine was followed by complete resolution of clinical signs and amelioration of laboratory abnormalities within 72 hours of treatment. N-acetylcysteine is a safe and probably an effective treatment for dactinomycin-induced hepatic sinusoidal obstructive syndrome.