Subepithelial pelvic hematoma (Antopol--Goldman lesion) simulating renal neoplasm: report of a case and review of the literature.

The Antopol-Goldman lesion is a subepithelial pelvic hematoma simulating a renal neoplasm. We report the clinico-pathological features of a single case and a review of the literature. A 76-year-old man presented with flank pain and hematuria. Computed tomography showed a hypodense lesion of 6 cm at the left kidney with filling defect at pyelogram. The patient underwent nephroureterectomy for suspected neoplasm. Macroscopically, a mass of 6 cm was present impinging on the pelvi-caliceal system. Microscopically, the lesion was composed by hemorragic material with feature of an hematoma. A diffuse eosinophilic amorphous material suspicious for amyloid was observed among intra- and extraparenchymal vessels. The Congo-Red staining verified the presence of amyloid. The diagnosis was subepithelial pelvic hematoma with severe amyloidosis. Antopol-Goldman lesion should be kept in mind as a possible differential diagnosis of upper urinary tract lesion to avoid unnecessary nephrectomies. The anamnestic knowledge of amiloydosis may increase this diagnostic hypothesis.