Clinical significance of pulmonary nodules detected by CT and Not CXR in patients treated for favorable histology Wilms tumor on national Wilms tumor studies‐4 and ‐5: A report from the Children's Oncology Group

Abstract

Metastatic lung disease in Wilms tumor (WT) patients was traditionally identified by chest radiograph (CXR). It is unclear whether patients with small lesions, detectable only by computed tomography ("CT-only" lesions), require the more intensive therapy, including doxorubicin and lung irradiation, given to patients with metastases detectable by CXR. This study involved 417 patients with favorable histology WT and isolated lung metastases (detected by CXR or CT) who were registered on National Wilms tumor Study (NWTS)-4 or -5. Outcomes by method of detection (CXR vs. CT-only), use of lung radiation, and 2- or 3-drug chemotherapy (dactinomycin and vincristine ± doxorubicin) were determined and compared using the log-rank test. There were 231 patients with lung lesions detected by CXR and 186 by CT-only. Of the patients with CT-only nodules, 37 received only 2 drugs and 101 did not receive lung radiation. Five-year event-free survival (EFS) was greater for patients receiving three drugs (including doxorubicin) with or without lung radiation than for those receiving two drugs (80% vs. 56%; P = 0.004). There was no difference seen in 5-year overall survival (OS) between the 3- and 2-drug subsets (87% vs. 86%; P = 0.91). There were no significant differences in EFS (82% vs. 72%; P = 0.13) or OS (91% vs. 83%; P = 0.46) for patients with CT-only nodules whether they received lung radiation or not. Our results suggest that patients with CT-only lung lesions may have improved EFS but not OS from the addition of doxorubicin but do not appear to benefit from pulmonary radiation.