Giant Lipoma with Fat Necrosis of the Back Mimicking Atypical Lipomatous Tumor in MRI Findings

Result: A 63-year-old man presented with a 2-year history of a subcutaneous nodule in his back. MRI showed that a 20 × 15 cm well-circumscribed tumor was located beneath the latissimus dorsi muscle with high signal intensities on both T1and T2weighted images and signal attenuation on fat suppression sequences. Inside the tumor, there were multiple thickened septa with gadolinium enhancement, which was consistent with atypical lipomatous tumor. However, we diagnosed this case as a lipoma with fat necrosis from the findings of an incisional biopsy and enucleation of the tumor was performed.