Is routine pelvic surveillance imaging necessary in patients with Wilms tumor?

Authors

  • Sue C. Kaste DO,

    Corresponding author
    1. Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee
    2. Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee
    3. Department of Radiology, University of Tennessee Health Science Center, Memphis, Tennessee
    • Department of Radiological Sciences, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MSN 220, Memphis, TN 38105-3678

    Search for more papers by this author
    • Fax: (901) 595-3981

  • Samuel L. Brady PhD,

    1. Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee
    Search for more papers by this author
  • Brian Yee RT(R)(CT), ARRT,

    1. Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee
    Search for more papers by this author
  • Valerie J. McPherson BS,

    1. Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee
    Search for more papers by this author
  • Robert A. Kaufman MD,

    1. Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee
    2. Department of Radiology, University of Tennessee Health Science Center, Memphis, Tennessee
    3. Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
    Search for more papers by this author
  • Catherine A. Billups MS,

    1. Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee
    Search for more papers by this author
  • Najat C. Daw MD,

    1. Department of Pediatrics, Division of Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
    Search for more papers by this author
  • Alberto S. Pappo MD

    1. Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee
    Search for more papers by this author

  • Presented as an oral presentation at the: International Pediatric Radiology Congress; May 27-31, 2011; London, United Kingdom.

Abstract

BACKGROUND:

It is unclear whether routine pelvic imaging is needed in patients with Wilms tumor. Thus, the primary objective of the current study was to examine the role of routine pelvic computed tomography (CT) in a cohort of pediatric patients with Wilms tumor.

METHODS:

With institutional review board approval, the authors retrospectively identified 110 patients who had Wilms tumor diagnosed between January 1999 and December 2009 with surveillance imaging that continued through March 2011. The authors estimated overall survival (OS), event-free survival (EFS), and dosimetry from dose length product (DLP) conversion to the effective dose (ED) for every CT in a subgroup of 80 patients who had CT studies obtained using contemporary scanners (2002-2011). Metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters were placed within organs of anthropomorphic phantoms to directly calculate the truncal ED. EDDLP was correlated with EDMOSFET to calculate potential pelvic dose savings.

RESULTS:

Eighty patients underwent 605 CT examinations that contained DLP information, including 352 CT scans of the chest, abdomen, and pelvis; 123 CT scans of the chest and abdomen; 102 CT scans of the chest only; 18 CT scans of the abdomen and pelvis; 9 CT scans of the abdomen only; and 1 CT that was limited to the pelvis. The respective 5-year OS and EFS estimates were 92.8% ± 3% and 2.6% ± 4.3%. Sixteen of 110 patients (15%) developed a relapse a median of 11.3 months (range, 5.0 months to 7.3 years) after diagnosis, and 4 patients died of disease recurrence. Three patients developed pelvic relapses, all 3 of which were symptomatic. The estimated ED savings from sex-neutral CT surveillance performed at a 120-kilovolt peak without pelvic imaging was calculated as 30.5% for the average patient aged 1 year, 30.4% for the average patient aged 5 years, 39.4% for the average patient aged 10 years, and 44.9% for the average patient aged 15 years.

CONCLUSIONS:

Omitting pelvic CT from the routine, off-therapy follow-up of patients with Wilms tumor saved an average 30% to 45% of the ED without compromising disease detection. Cancer 2013. © 2012 American Cancer Society.

Ancillary