An asymptomatic subcutaneous nodule of the lower back: A sentinel lesion for a diagnosis not to be missed

摘要

A 2-year-old boy without any relevant personal or familial history was referred to our department for investigation of 2 large nodules in the temporal region and lower back, respectively (Figs. 1, 2). These lesions were not believed to have been present at birth, but their exact date of onset could not be specified. The nodules were asymptomatic and nonspecific, firm, oblong, poorly delimited, mobile, and flesh-colored, with the larger of the two (located on his back) measuring 7x7 cm. Three more lesions resembling epidermal cysts were found in the occipital region and the vertex. Magnetic resonance imaging of the lumbar region only showed a fine hyposignal infiltrating the paraspinal muscles. A shave biopsy of the temporal nodule was inconclusive, and another punch biopsy from the lower back nodule was then performed. It was first diagnosed as a desmoid tumor or a fibrous collagenic hamartoma. The material was referred to our center (Figs. 3-6).