No abstract

Members of the p160 steroid receptor cofactor family, including AIB1 (Amplified in Breast Cancer 1) (also known as SRC-3/RAC3/ACTR/pCIP/TRAM-1), are of interest in endometrial carcinoma as they affect the function of estrogen (ER) and progesterone receptors (PR). Since it is feasible that alterations in the expression levels of coregulators can either augment ER activity or reduce the ability of PR to oppose ER action in endometrial cancers, our primary aim was to analyze expression of the AIB1 protein in endometrial carcinoma, carcinomaassociated complex atypical hyperplasia, and carcinoma-associated normal endometrium using immunohistochemistry and tissue microarrays. Expression of AIB1 was compared with other biomarkers and clinicopathologic parameters. We also tested AIB1 expression in non-carcinoma associated hyperplastic, normal secretory and proliferative endometrium to determine baseline AIB1 levels. In endometrial carcinoma, there is a higher expression of AIB1 compared to carcinoma-associated complex atypical hyperplasia (0.007) or carcinoma-associated normal endometrium (o0.001). AIB1 expression correlates with older age (P ¼ 0.003), peri-or postmenopausal status (P ¼ 0.002) and a higher grade of carcinomas (P ¼ 0.04). There were no differences in the expression of additional steroid hormone receptor co-activators (SRC-1 and p300/CBP) and the co-repressor SMRT between histologic categories. AIB1 expression correlated with ER (r ¼ 0.30, P ¼ 0.006). The strongest correlation was between ER and PR-B isoform nuclear expression (r ¼ 0.52, Po0.0001). AIB1 levels were higher in non-carcinoma associated normal and hyperplastic endometrium compared to carcinomaassociated complex atypical hyperplasia and carcinoma-associated normal endometrium, and were the highest in normal secretory endometrium. In conclusion, high AIB1 expression in endometrial carcinoma is associated with parameters of poor prognosis. We propose that when AIB1 is overexpressed in endometrial carcinoma, ER action is augmented, leading to endometrial hyperplasia and progression to malignancy. Future studies correlating expression with response to hormonal therapy may be beneficial.

Acquired elastotic hemangioma is a distinctive variant of hemangioma which should be differentiated from other cutaneous vascular tumors with a hobnail endothelial pattern, including angiosarcoma. The expression of D2-40 in most cases suggests a lymphatic origin of this acquired vascular proliferation.

We report an unusual case of primary cutaneous T-cell lymphoma in a 45-year-old male showing expression of the B-cell marker CD20. The lesion presented as a large plaque on the right shin and rapidly developed into additional lesions on the right lower leg and right anterior chest. Despite therapy, bone involvement was discovered at 1 year after initial presentation. Punch biopsy of the right leg revealed a diffuse, atypical dermal lymphocytic infiltrate with papillary edema and no epidermotropism. The atypical cells strongly expressed the T-cell markers CD3, CD2, and CD43, with additional expression of cytotoxic T-cell markers CD8, cytotoxic granule-associated RNA binding protein (TIA-1), and granzyme B and loss of CD7 by immunohistochemistry (IHC). In addition, the atypical cells with the above phenotype exhibited moderate expression of CD20 by IHC. Coexpression of CD8 and CD20 in the atypical cells was confirmed by a dual-labeled IHC stain. Clonal rearrangements of the T-cell receptor gamma- and beta-chain genes were detected by polymerase chain reaction; however, there was no expression of T-cell receptor beta-chain identified by IHC. In conclusion, we present a case a of CD8-positive primary cutaneous T-cell lymphoma with CD20 expression, exhibiting aggressive behavior.

Luminal cytokeratin (CK) expression in breast papillary lesions, and its potential diagnostic utility among other markers in distinguishing between papillomas and papillary carcinomas, has not been previously evaluated. Such expression was determined in 42 papillary lesions (18 papillary carcinomas and 24 papillomas) by immunostaining with a CK5/p63/CK8/18 antibody cocktail. The mean CK8/18 intensity score and percentage of positive cells were significantly higher in papillary carcinomas (227 and 95%, respectively, vs 86 and 42% in papillomas; both P-values o0.0001), whereas the mean CK5 intensity score and percentage of positive cells were significantly lower (7 and 5%, respectively, vs 107 and 58% in papillomas; both P-values o0.0001). Half (9/18) of the papillary carcinomas expressed p63 vs all (24/24) of the papillomas (P ¼ 0.0001). P63 expression in papillary carcinoma was always (9/9; 100%) focal/limited in nature (expression in o10% of cells), whereas focal expression was seen in only four (17%) papillomas (Po0.0001). Both differential CK (CK8/18 and CK5) expression and p63 were equally sensitive (100%) for the diagnosis of papillary carcinoma, but differential CK expression was more specific (96 vs 83%), resulting in a greater accuracy. However, the best discriminatory power in the distinction from papilloma was achieved when all three markers were used in combination, resulting in 100% sensitivity and specificity values. It is concluded that breast papillary lesions have differential CK expression profiles that, especially in combination with p63, can be useful for their stratification, potentially also in needle biopsy material, in which more accurate and reproducible characterization is needed. Modern Pathology (2011) 24, 185-193; doi:10.1038/modpathol.2010; published online 12 November 2010 Keywords: breast; cytokeratin 5; cytokeratin 8/18; luminal cytokeratin; p63; papillary carcinoma; papilloma By comprising only 1-2% of breast lesions, 1 papillary lesions are relatively rare. Despite that, recognizing that a breast lesion is papillary in nature is not particularly difficult for pathologists. On the other hand, distinguishing between various types of papillary lesions can be problematic. 2,3 Such lesions include intraductal papilloma, intraductal papilloma with atypical ductal hyperplasia, intraductal papilloma with ductal carcinoma in-situ, papillary ductal carcinoma in-situ, intracystic