A 15-year-old Girl with an Asymmetric Hemitruncal Fat Distribution: Hemihyperthrophy or Hemiatrophy?

A 15-year-old girl was referred by her pediatrician to the plastic surgeon because of complaints of an asymmetric truncal fat distribution. Written informed consent was obtained from the patient and the parents of the patient for publication of this case report and accompanying images. She complained of back pain with a postural disbalance because of an excessive mass on the right, which she also experienced as a disfigurement. Physical examination demonstrated an asymmetry of the trunk in favor of the right side, with also a breast asymmetry of 2 sizes (Fig. ​(Fig.1).1). Ultrasound and magnetic resonance imaging demonstrated an asymmetric distribution of subcutaneous fat, with excessive fat at the right flank and lower back, with a maximum diameter of 6.7 cm to the right iliac crest compared with a maximum diameter of 4.6 cm on the left side, not suspect for lipoma (Fig. ​(Fig.2).2). No scoliosis was found. Her medical history revealed a left-sided stage III Wilms tumor at age 2 for which she was successfully treated with a left-sided radical nephrectomy and simultaneous central line placement, followed by systemic chemotherapy and local radiotherapy of the left abdominal side according to the NWTS-5 protocol.1 Radiotherapy was given with 6 MV photons. A dose of 10.8 Gy was applied by means of 2 fields, anterior-posterior/posterior-anterior, in 6 fractions over a period of 7 days. The radiation field included the sacral vertebra 1 up to the thoracic vertebra 10, with the lower field limit halfway through the sacroiliac joints. The contralateral kidney, ovaries, and uterus were not included in the target volume. Until today, no metastases or tumor recurrence is present.