Usha Raju

Epitheliosis of the breast: An immunohistochemical characterization and comparison to malignant intraductal proliferations of the breast

Epitheliosis is a benign intraluminal proliferation in the breast ducts and lobules that needs to be distinguished from ductal carcinoma in situ (DCIS). The histogenesis and differentiation of cells comprising epitheliosis have been the subject of some controversy. We evaluated the expression of a high-molecular-weight keratin (34βE12), muscle-specific actin (HHF-35), and S-100 protein immunoreactivity in formalin-fixed sections of the breast with epitheliosis and DCIS. In 28 of 30 cases of epitheliosis, there was strong HMW keratin immunoreactivity in the streaming sheetlike intraluminal proliferations. In contrast, 35 of 40 cases of DCIS (nonpapillary and papillary) were nonreactive for HMW keratin; the other five were weakly reactive. Furthermore, in 10 cases of DCIS, some ducts had isolated or small aggregates of HMW keratin-positive benign cells on the luminal aspects of the neoplastic proliferation that were reminiscent of a pagetoid pattern. Muscle actin-stained sections were analyzed to assess myoepithelial (ME) cell participation in epitheliosis. Muscle actin-positive ME cells were present at the periphery of the involved ducts but were absent or rare within epitheliosis. The distribution of ME cells–i.e., at the periphery of the spaces involved–was similar in DCIS and epitheliosis. S-100 protein was weakly but relatively consistently expressed by epitheliosis, but all cases of DCIS were negative. Six cases of atypical ductal hyperplasia included in the study were negative for HMW keratin, muscle actin, and S-100 protein. The immunohistochemical profile of epitheliosis indicates that it is primarily an epithelial proliferation with strong HMW keratin and weak S-100 protein expression but without ME cell participation. The distinct differences in HMW keratin expression of epitheliosis and intraductal carcinoma appear to reflect a consistent antigenic difference in these two biologically distinct forms of proliferation.

Breast cancer incidence in a cohort of women with benign breast disease from a multiethnic, primary health care population.

Abstract:  Women with benign breast diseases (BBD), particularly those with lesions classified as proliferative, have previously been reported to be at increased risk for subsequent development of breast cancer (BC). A cohort of 4970 women with biopsy‐proven BBD, identified after histopathology review of BBD biopsies, was studied for determination of subsequent development of BC. We report on 4537 eligible women, 28% of whom are African‐American, whose BBD mass was evaluable for pathologic assessment of breast tissue. Ascertainment of subsequent progression to BC from BBD was accomplished through examination of the tumor registries of the Henry Ford Health system, the Detroit SEER registry, and the State of Michigan cancer registry. Incidence rates (IR) are reported per 100,000 person years at risk (100 k pyr). Poisson regression models were used to evaluate the association of demographic and lesion characteristics with BC incidence, using person years at the time of BBD diagnosis as the offset variable. The estimated overall BC IR for this cohort is 452 (95% confidence interval [CI] = 394–519) per 100 k pyr. Incidence for women age 50 and older is 80% greater than for younger women (p = 0.007, IRR = 1.8, 95% CI = 1.36–2.36). Neither marital status (p = 0.91, IRR = 0.97, 95% CI = 0.73–1.29) nor race (p = 0.67, IRR = 0.9, 95% CI = 0.54–1.48) is associated with differences in BC IR. Compared with women having nonproliferative lesions, the risk for BC is greater for women with atypical ductal hyperplasia of (IRR = 5.0; 95%CI = 2.26–11.0; p < 0.001) and other proliferative lesions (IR = 1.7, 95% CI = 1.02–2.95; p = 0.04). BC risk for woman with atypical lesions is significantly higher than for women with proliferative lesions without atypia (IRR = 2.58, 95% CI = 1.35–4.90; p = 0.0039). Neither race nor marital status was a factor for BC incidence from BBD in this cohort. Age retained its importance as a predictor of risk. BBD lesion histopathology in the outcome categories of either proliferative without atypia or proliferative with atypia are significant risk factors for BC, even when adjusted for the influence of demographic characteristics. The risks associated with BBD histological classifications were not different across races.

Primary cutaneous mucinous carcinoma: Presence of myoepithelial cells as a clue to the cutaneous origin

Background:Primary cutaneous mucinous carcinoma (PCMC) is a rare malignancy with probable apocrine differentiation. It is important to differentiate it from metastatic mucinous carcinoma (MMC), especially from the breast. The histologic and immunohistochemical features overlap between PCMC and breast mucinous carcinomas. In this study, we introduce the presence of myoepithelial component in PCMC as a new morphologic parameter to distinguish it from MMC from either breast or sites elsewhere in the body. Materials and Methods:We studied 7 cases of PCMC. The possible in situ component in the tumor was assessed by the presence of a peripheral myoepithelial cell layer. Myoepithelial cell differentiation was confirmed with immunohistochemical stains for p63, CK 5/6, calponin, smooth muscle actin (SMA), HHF-35, and CD10. Estrogen and progesterone receptor (ER/PR), gross cystic disease fluid protein (GCDFP 15), CK7, CK20, and S-100 immunostains were also performed. Results:Histologically, multiple small monomorphic epithelial islands floating in multilocular pools of mucin characterized the tumor. Focally, epithelial islands were bordered by dermal connective tissue at the periphery of mucin pools. Secretory snouts were apparent in all cases providing evidence for apocrine differentiation. In 5 of the 7 cases, an in situ component was identified as epithelial islands being bounded by a myoepithelial layer, which was highlighted by p63, CK 5/6, calponin, SMA, and HHF-35. ER/PR and CK7 were positive in all the cases. GCDFP-15 and CD10 were focally positive in the tumor cells and myoepithelial cells, respectively. All 7 cases were negative for S-100 and CK 20. Conclusion:We conclude that an in situ component is frequently present in PCMC (5/7) and may help in distinguishing this entity from MMC, especially of breast origin. Furthermore, it may provide insight into the pathogenetic mechanism of mucinous carcinoma evolving from in situ carcinoma with luminal mucinous distention to cellular tumor with a little surrounding mucin.

Congenital testicular juvenile granulosa cell tumor in a neonate with X/XY mosaicism

A congenital sex cord-stromal tumor of the testis with morphologic features of juvenile granulosa cell tumor is reported. The tumor occurred in an abdominal testis of a newborn infant with an X/XY karyotype and ambiguous genitalia and presented as a partially cystic mass associated with ascites. Histologically the tumor was comprised of an admixture of solid, cellular, poorly differentiated lobules mimicking graafian follicles. Residual hypoplastic testicular tissue was present at the periphery. This is the 19th reported case of testicular juvenile granulosa cell tumor and the fourth with an underlying sex chromosome anomaly, further emphasizing the relationship of this uncommon neoplasm to abnormal sexual or gonadal development.

Multiplicity of Benign Breast Lesions Is a Risk Factor for Progression to Breast Cancer

Purpose: Benign breast disease (BBD) in women encompasses a broad spectrum of histopathologic lesions. Studies on BBD have focused on the risks for subsequent breast cancer associated with three broad categories of lesions, classified as nonproliferative, proliferative, or proliferative with atypia, without addressing the issue of the contribution of concurrent multiple BBD lesions. There is very limited information with regard to the issue of BBD lesion multiplicity and breast cancer risk. Experimental Design: We evaluated a detailed microscopic spectrum of 18 BBD lesions from fibrosis to atypical hyperplasia in a BBD cohort of 4,544 subjects, within which 4.5% (n = 201) developed breast cancer during an average follow-up period of 10.3 years. Lesions were defined as nonproliferative (8 diagnoses; risk level 1 = no risk or low risk), proliferative without atypical hyperplasia (8 diagnoses; risk level 2 = intermediate risk), and proliferative with atypical hyperplasia (2 diagnoses; risk level 3 = highest risk level). Twenty variables including age (≥50 or <50 years) at the time of BBD diagnosis and race (African American or non–African American) were assessed. A categorical variable, surrogate for lesion type and number, was represented initially by four levels: 1, nonproliferative = 1 (reference); 2, nonproliferative > 1; 3, proliferative = 1; and 4, proliferative > 1. Results: The majority of BBD subjects in our cohort (almost 70%) had more than one BBD lesion. Concurrent multiple nonproliferative or proliferative BBD lesions with or without atypia in a BBD biopsy and age are significant predictors of risk for progression of BBD to breast cancer. The presence of atypical hyperplasia in a BBD biopsy alone or in conjunction with other lesions without atypia conferred higher risks. Women with fibrosis had a reduced risk for progression to breast cancer. Race was not a significant predictor of progression to breast cancer. The effect of age, fibrosis, and multiple lesions (whether nonproliferative, proliferative, or atypia) on breast cancer progression was not influenced by race. Conclusion: BBD lesion multiplicity is frequent, and teasing out the heterogeneity of multiple concurrent BBD lesions is warranted to refine and improve risk estimates for progression of breast cancer from BBD.

Congenital polycystic tumor of the atrioventricular node (endodermal heterotopia, mesothelioma): A histogenetic appraisal with evidence for its endodermal origin

The small, variously designated, primary atrioventricular node tumor has been considered to be of endothelial, endodermal, or mesothelial origin. To identify its derivation, we studied seven tumors using silver staining and immunocytochemical labeling with a variety of antibodies. Cytoplasmic argyrophil granules but not argentaffin granules were found in isolated cells among the more numerous tubule-lining cells in four tumors. Serotonin and calcitonin were demonstrable in seven and six tumors, respectively, in a similar distribution to that of the argyrophil cells. A positive reaction of different distribution from that of the argyrophil cells was noted in a varying number of tubule-lining cells for carcinoembryonic antigen, epithelial membrane antigen, and blood group antigen in seven, four, and seven tumors, respectively. No activity was noted in the tumor cells for factor VIII-related antigen or a number of peptides. An endodermal rather than mesothelial or epithelial origin for the tumor is substantiated by the presence of neuroendocrine cells in the midst of the more numerous carcinoembryonic-antigen-positive lining cells of the tumor tubules.

Molecular classification of breast carcinoma in situ.

Pleomorphic variant of invasive lobular carcinoma (PILC) is an aggressive variant of invasive lobular carcinoma (ILC). Its in situ counterpart, pleomorphic lobular carcinoma in situ (PLCIS) is a recently described entity. Morphologically it has the typical architectural pattern of LCIS, but the neoplastic cells resemble intermediate grade DCIS. Molecular signatures that distinguish PLCIS from DCIS and LCIS would provide additional tools to aid in the histopathologic classification of PLCIS as a lesion distinct from LCIS and DCIS. CIS lesions, obtained from a study cohort of 38 breast cancer patients, were divided into 18 DCIS, 14 PLCIS and 6 LCIS. DNA from microdissected archival tissue was interrogated for loss or gain of 112 breast-cancer-specific genes using the Multiplex Ligation-dependent Probe Amplification Assay (MLPA). Classification Regression Tree (CART) analysis was employed to develop a gene-based molecular classification to distinguish or separate out PLCIS from DCIS and LCIS. Molecular classification via CART, based on gene copy number, agreed with histopathology in 34/38 CIS cases. Loss of CASP1 was predictive of LCIS (n=4) with one misclassified PLCIS. Gain of RELA predicted only the LCIS classification (n=2 cases). STK15 and TNFRSF1B were predictive only for DCIS with no misclassifications. Gain of EHF and TNFRSF1B and loss of NCOA3 were predictive of PLCIS, but not without misclassification. Molecular reclassification by CART was accomplished in 4 CIS cases: 1 PLCIS was reclassified as LCIS, 1 LCIS reclassified as PLCIS, and 2 DCIS cases as PLCIS. This study provides additional rationale for molecular modeling strategies in the evaluation of CIS lesions. This diagnostic aid may serve to minimize misclassification between PLCIS and DCIS, and PLCIS and LCIS, aiding to increase accuracy in the differential diagnosis of CIS lesions.

Delineating an Epigenetic Continuum for Initiation, Transformation and Progression to Breast Cancer

Aberrant methylation of promoter CpG islands is a hallmark of human cancers and is an early event in carcinogenesis. We examined whether promoter hypermethylation contributes to the pathogenesis of benign breast lesions along a progression continuum to invasive breast cancer. The exploratory study cohort comprised 17 breast cancer patients with multiple benign and/or in situ lesions concurrently present with invasive carcinoma within a tumor biopsy. DNA from tumor tissue, normal breast epithelium when present, benign lesions (fibroadenoma, hyperplasia, papilloma, sclerosing adenosis, apocrine metaplasia, atypical lobular hyperplasia or atypical ductal hyperplasia), and in situ lesions of lobular carcinoma and ductal carcinoma were interrogated for promoter methylation status in 22 tumor suppressor genes using the multiplex ligation-dependent probe amplification assay (MS-MLPA). Methylation specific PCR was performed to confirm hypermethylation detected by MS-MLPA. Promoter methylation was detected in 11/22 tumor suppressor genes in 16/17 cases. Hypermethylation of RASSF1 was most frequent, present in 14/17 cases, followed by APC in 12/17, and GSTP1 in 9/17 cases with establishment of an epigenetic monocloncal progression continuum to invasive breast cancer. Hypermethylated promoter regions in normal breast epithelium, benign, and premalignant lesions within the same tumor biopsy implicate RASSF1, APC, GSTP1, TIMP3, CDKN2B, CDKN2A, ESR1, CDH13, RARB, CASP8, and TP73 as early events. DNA hypermethylation underlies the pathogenesis of step-wise transformation along a monoclonal continuum from normal to preneoplasia to invasive breast cancer.