Lipomembranous fat necrosis in three cases of testicular torsion

Aims: To describe for the first time a lesion termed lipomembranous fat nec rosis (LFN) in three patients with spermatic cord torsion. Methods and results: We reviewed 386 testes and their epididymides and sper matic cords which had been removed for testicular infarction. For the three cases showing LFN, a battery of histochemical tests (including periodic ac id-Schiff (PAS), orcein, Sudan black and Perls stains) was applied and clin ical histories and laboratory data were also investigated. Findings were si milar in the three specimens, The testes showed a central group of necrotic seminiferous tubules which were surrounded by granulation tissue consistin g of macrophages, multinucleated giant cells, lymphocytes, plasma cells and fibrous connective tissue at the periphery of the lesion. The spermatic co rd showed thrombosed veins surrounded by fat necrosis showing cystic caviti es which were bounded by wavy hyaline membranes. These stained with Sudan b lack, PAS (before and after diastase digestion) and orcein and presented ye llowish-green autofluorescence. Conclusions: Lipomembranous fat necrosis of the spermatic cord is a distinc tive entity which seems to be related to spermatic cord torsion and the dif ferential diagnosis of which should be established with regard to the prese nce of parasites, sclerosing lipogranuloma and granuloma evoked by rupture of a testicular prosthesis.