Résumé
Perivascular epithelioid cell tumor (PEComa) is a rare family of related mesenchymal neoplasms that include angiomyolipoma, lymphangiomyomatosis and clear cell 'sugar' tumor of the lung. Although this type of tumor has been described in the literature in organs such as kidney, lung, uterus and urinary bladder, there are few reports of gastrointestinal tract-related tumor. We report here on a case of PEComa arising in the transverse colon. This occurred in a 41-year-old male who had no history of tuberous sclerosis complex. Histopathologically, the tumor consisted of nests or sheets of epithelioid cells with eosinophilic cytoplasm. The tumor cells were positive for HMB-45, vimentin and caldesmon, but they were negative for S-100 protein, cytokeratin and CD117, according to immunohistochemical staining. Careful follow up is warranted because the biological behavior of PEComa has not yet been documented. We present here a case of colonic PEComa that was confirmed by immunohistochemical staining and the histopathologic findings, and we include a review of the literature.
Sujets)
Adulte , Humains , Mâle , Angiomyolipome , Protéines de liaison à la calmoduline , Côlon , Côlon transverse , Cytoplasme , Granulocytes éosinophiles , Cellules épithélioïdes , Kératines , Rein , Poumon , Lymphangioléiomyomatose , Tumeurs des cellules épithélioïdes périvasculaires , Protéines S100 , Complexe de la sclérose tubéreuse , Vessie urinaire , Utérus , VimentineRésumé
Isolated heaptic tuberculous granuloma with no coexistent tuberculosis elsewhere in the body is extremely rare. We report a case of pathologically proven tuberculous granuloma in the liver followed with both IV bolus and portal CT scans. The lesion on preenhanced CT scan showed undefinable isodensity. After IV bolus injection, it showed poor enhancement with central low-density and surrounding hyperdenity due to compensatory hypervascularity of the left lobe of liver in early phase. It showed peripheral rim enhancement in late phase and in delayed phase showed relatively homogeneous but slightly decreased contract enhancement. On portal CT scan, it showed a hypodense portal defect similar to other hepatic mass lesions. During follow-up studies, it was a slowly growing mass which was more easily detectable by prtal CT scans than bolus CT scans.