Monoamine Oxidase B in Renal Cell Carcinoma.

BACKGROUND Studies on monoamine oxidase B (MAO-B) expression in renal cell carcinoma (RCC) are lacking. This study focused on the immunohistochemical evaluation of MAO-B in RCC. MATERIAL AND METHODS Sixty-three RCC samples were compared on basic clinical and histopathological parameters, including histopathological type and tumor grade. RCC samples were divided according to the histopathological type into 2 groups: conventional type (51 samples) and other types (12 samples). For MAO-B detection, a standard immunohistochemical procedure was employed. RESULTS In healthy kidney samples, MAO-B was detected predominantly in tubules. Fifty-two cancer tissue samples were MAO-B negative and 11 tissue samples were MAO-B low positive. Enzymes were detected only in the cytoplasm. We did not find any significant correlation between the percentage of positive MAO-B specimens and nuclear grade. Additionally, Fisher's test did not reveal any difference in numbers of positive and negative MAO-B samples between the 2 RCC types (P>0.05). CONCLUSIONS From our results, it was clear that MAO-B expression played no significant role in stimulation of renal cancer development. We found that MAO-B occurred only in 19% of kidney tumors and that the positivity of protein expression was low. Moreover, it seems that the disappearance of this enzyme in RCC is a consequence of replacement of healthy tissue by cancer cells. On the other hand, one can assume that the loss of MAO-B expression could be associated with severe pathological processes in the kidney.

Foamy cell angiosarcoma is a diagnostic pitfall: a case report of an angiosarcoma mimicking xanthoma.

The authors report a case of cutaneous angiosarcoma, composed predominantly of cytologically bland foamy cells, mimicking cutaneous xanthoma, dermal clear cell mesenchymal neoplasm, or clear cell dermatofibroma. The tumor occurred on the forehead and scalp of an 86-year-old white man with no history of radiation exposure. The tumor cells were positive for CD31, CD34, D2-40, FLI-1, and ERG, and were negative for CD68 and CD163. Conventional vasoformative areas, with atypia and mitoses that led to the correct final diagnosis, were found only in 1 of the 2 performed biopsies. Foamy cell angiosarcoma is probably one of the least common variants of cutaneous angiosarcoma and represents an important diagnostic pitfall.

Association between polymorphisms of XRCC1, p53 and MDR1 genes, the expression of their protein products and prognostic significance in human breast cancer.

BACKGROUND: This study aimed to examine the relationship between XRCC1, p53 and MDR1 protein, along with polymorphisms of their genes and their prognostic values in breast cancer. The following clinical and pathological parameters were evaluated: histopathological type of tumor, grade, stage, Her2/neu expression, ER, PR positivity and involvement of regional lymph nodes. MATERIAL/METHODS: Expression of proteins was determined in 39 samples of breast cancer by immunohistochemistry. Nucleotide polymorphisms were analyzed by PCR-RFLP. For statistical analysis, chi-square test (Yates), Fisher's exact test, and correlation test were used to analyze the data. RESULTS: The highest protein expression was immunohistochemically found in MDR1 protein, with 54% of samples testing positive. In addition, the evaluation of MDR1 expression revealed higher positive immunoreactivity in lobular (LIC) and other types of tumor in comparison to ductal (DIC) type. The expression of p53 and XRCC1 protein was equal, but lower compared to MDR1, both testing positive in 36% of all tissue samples. Comparison of XRCC1 protein and histopathological type of tumor revealed that DIC and LIC types were mostly XRCC1-negative, while other types, papillary and mucinous were more likely to be XRCC1-positive. Interestingly, when evaluating LIC samples separately, a negative correlation between the Her2/neu and expression of XRCC1 was detected. Apparently, all Her2/neu-positive samples were XRCC1-negative (6/86%). The correlation test indicated a negative correlation between Her2/neu-positive samples and XRCC1-negative specimens (r = 1, p < 0.05). Statistical analysis did not reveal a correlation of p53 expression with clinical and pathological parameters. Similarly, no statistically significant difference was found between the tested polymorphisms and protein expression. CONCLUSIONS: We did not find statistically significant correlation between tested polymorphisms and their protein expression.

Juxtaglomerular cell tumor, causing fetal demise.

AIMS: This case report describes juxtaglomerular cell tumor-a rare renin-producing tumor of the kidney, complicating pregnancy. CLINICAL CASE: A previously healthy 24-year-old primigravid woman developed hypertension in the 20th week of pregnancy, leading to a miscarriage in the 28th week. However, hypertension continued after the miscarriage. A more complete examination revealed a solid tumor in the lower pole of the right kidney. The patient underwent a partial right nephrectomy. A histological examination and electron microscopy confirmed the diagnosis of JGCT. The patient's blood pressure was normalized within 2 weeks. CONCLUSIONS: JGCT can lead to miscarriage if undiscovered during pregnancy. A kidney ultrasound should be performed on pregnant women with newly detected hypertension. No staining in early phase of contrast CT is the feature that differentiates JGCT from renal cell carcinoma. These tumors are benign, with only one reported exception, and nephron-sparing surgery is preferable.