Neoadjuvant Transcatheter Arterial Chemoembolization and Systemic Chemotherapy for the Treatment of Wilms Tumor

ABSTRACT

From 2003 to 2013, 55 patients (median age 3.3 years; 29 males, 26 females) with unresectable, metastatic, or diffuse anaplastic histology (AH) Wilms tumor were treated with neoadjuvant transcatheter arterial chemoembolization (TACE) and systemic chemotherapy. Characteristics of patients were maximal tumor diameter greater than 10 cm, involvement of periaortic lymph nodes, tumor thrombus in inferior vena cava/right atrium, distal metastasis, or diffuse AH. The chemoembolic emulsion for TACE consisted of pirarubicin, vindesine, and iodized oil. For the tumor with distal metastasis or diffuse AH, cisplatin was added in the chemoembolic emulsion. Intravenous chemotherapy with vindesine and actinomycin D was administered 2–3 weeks after TACE. For the patients with distal metastasis or diffuse AH Wilms tumor, intravenous chemotherapy consisted of ifosfamide and etoposide. Nephrectomy was performed 2–3 weeks after preoperative combination therapy. Surgical stage was assigned according to local operative findings in terms of the National Wilms Tumor Study (NWTS) Group combined with the pretherapeutic imaging to define metastatic disease. Postoperative treatment was based on tumor histology and surgical stage. All patients were followed up for 17–141 months (median: 82 months). No cardiotoxicity, renal insufficiency, and hepatic dysfunction after neoadjuvant TACE and systemic chemotherapy were found. Oral mucositis developed in 5 patients, grade I–II marrow suppression developed in 12 patients, and 19 patients became moderately febrile. In terms of response evaluation criteria in solid tumors, partial response (PR) in 34 (61.8%), stable disease (SD) in 19 (34.5%), and progressive disease (PD) in 2 (3.6%) patients were observed. Four of five patients had complete regression of inferior vena cava tumor thrombus. Atrial tumor thrombus retreated to inferior vena cava in one of two patients. Distant metastasis disappeared in four of six cases. Fifty patients (90.1%) underwent complete tumor resection. Tumor spillage occurred in 3 patients (5.5%). Two patients (3.6%) had microscopic residual disease. Surgical stages were stage II in 25, stage III in 24, and stage IV in 6 patients. On pathologic examination, tumor necrosis was >90% in 14 (25.5%), 50%–90% in 23 (41.8%), and <50% in 18 cases (32.7%). The 5-year event-free survival was 92.7%, and the over¬all survival was 94.5%. These preliminary results suggest that the use of neoadjuvant TACE and systemic chemotherapy may provide a promising choice in the treatment of unresectable, metastatic, or diffuse AH Wilms tumor in children. Further investigations are necessary.