Renal expression of hypoxia inducible factor-1α in patients with chronic kidney disease: a clinicopathologic study from nephrectomized kidneys.

Background & objectives: Hypoxia inducible factor-1α (HIF-1α) has been shown to play a role in the pathogenesis of renal interstitial fibrosis. However, the relationship of HIF-1α expression intensity in human renal tissue with the degree of renal function or renal fibrosis has not been investigated. We therefore, undertook this study to assess the relationship between HIF-1α expression and degree of renal impairment and renal fibrosis using renal tissue from nephrectomized kidneys from patients with chronic kidney disease. Methods: This retrospective study was performed with 70 patients undergoing unilateral or bilateral nephrectomy because of renal cell carcinoma, urothelial cell carcinoma, or renal abscess. Immunohistochemical analysis of HIF-1α expression in non-tumourous or non-abscess renal parenchyma was performed. The patients were divided into two groups: group 1 (n=37) with low intensity HIF-1α expression and group 2 (n=33) with high intensity HIF-1α expression. Results: The intensity of renal HIF-1α expression was significantly associated with serum creatinine level (P=0.005), estimated glomerular filtration rate (P=0.02), fibrosis score of the interstitium (P=0.004) and glomerular sclerosis (P=0.013). A high intensity of HIF-1α expression tended to be associated with lower serum creatinine, higher estimated glomerular filtration rate, low interstitial fibrosis score and low glomerular sclerosis. In addition, multivariate analysis by step-wise logistic regression demonstrated that interstitial fibrosis was the only independent factor associated with the intensity of renal HIF-1α expression (OR 4.107, CI 1.535-11.313, P=0.005). Interpretation & conclusions: This study demonstrated a correlation between intensity of HIF-1α expression and degree of renal interstitial fibrosis. The association demonstrated an elevated HIF-1α expression in less severe kidney disease. The intensity of HIF-1α renal expression plays a role in the pathogenesis of chronic kidney disease.

Borderline clear cell adenofibroma with extensive hemorrhagic necrosis

Borderline clear cell adenofibroma of the ovary is rather rare since most of clear cell tumors are carcinomas. We report a case of ovarian borderline clear cell adenofibroma in a 52-year-old postmenopausal woman. The tumor had the characteristic histologic features of borderline clear cell adenofibroma except for central extensive hemorrhagic necrosis. The prognosis of borderline clear cell adenofibroma is excellent. Because the invasiveness cannot be assessed in the necrotic areas, our patient needed long-term follow-up

Perivascular epithelioid cell tumor [PEComa] of the uterus with aggressive behavior at presentation

Perivascular epithelioid cell tumor [PEComa] is a rare mesenchymal tumor composed of histologically and immunohistochemically distinctive perivascular epithelioid cells [PECs]. Both benign and malignant tumors have been identified, but the criteria for diagnosis of malignancy have not been fully established due to the rarity of the tumor. We report on a case of uterine PEComa in a 33-year old woman with lymph node metastasis at presentation. The tumor had the characteristic histologic features of PEComa with cytologic atypia, mitotic activity of 2/10 high power field [HPF], and necrosis; it exhibited immunopositivity for HMB-45, calponin and desmin and was negative for melan-A. The patient received neoadjuvant chemotherapy, debulking surgery and adjuvant chemotherapy. No evidence of recurrence or metastasis was apparent 8 months after surgery