Marlo M. Nicolas

The potential impact of reproducibility of Gleason grading in men with early stage prostate cancer managed by active surveillance: a multi-institutional study.

PURPOSE We evaluated the reproducibility of Gleason grading as relevant to the clinical treatment of men on active surveillance. MATERIALS AND METHODS Three sets of digital images of prostatic adenocarcinoma in biopsies were reviewed and assigned Gleason scores by a total of 11 pathologists from 7 institutions. Interobserver and intra-observer reproducibility were assessed for assignment of the highest Gleason pattern (3 vs 4 or higher). We also identified 97 consecutive patients on active surveillance. Prostate biopsy glass slides from 82 of the patients were available for re-review and the frequency of carcinoma requiring the distinction of tangentially sectioned Gleason pattern 3 from 4 was determined. RESULTS Interobserver reproducibility for classic Gleason patterns was substantial (Lights κ 0.76). Interobserver reproducibility for the histological distinction of tangentially sectioned Gleason pattern 3 from Gleason pattern 4 was only fair (Lights κ 0.27). Intra-observer reproducibility ranged from 65% to 100% (mean 81.5%). Of the 82 patients on active surveillance 61 had carcinoma and 15 (24.5%) had a set of biopsies with at least 1 focus in which the distinction between tangentially sectioned Gleason pattern 3 and poorly formed pattern 4 glands had to be considered. CONCLUSIONS The reproducibility of grading classic Gleason patterns is high. However, variability in grading occurred when distinguishing between tangentially sectioned pattern 3 glands and the poorly formed gland subset of pattern 4. Developing universally accepted histological and/or molecular criteria to distinguish these patterns and subsequently characterizing their natural history would be useful when treating patients on active surveillance.

Even low-level HER2 expression may be associated with worse outcome in node-positive breast cancer.

HER2 is an important predictive marker for response to trastuzumab and lapatinib in breast cancer. It is also a powerful prognostic marker in node-positive patients. Although standardized assays are used to help select patients for anti-HER2 therapy, there are no standardized criteria for assessing HER2 as a prognostic marker. Recent data using quantitative image analysis suggest that both high and low HER2 expression are associated with poor clinical outcome. Using the immunohistochemical scoring criteria currently recommended by the College of American Pathologists and American Society of Clinical Oncology to help select patients for trastuzumab, we evaluated HER2 protein expression in tumor tissue microarrays of 91 node-positive patients with invasive breast carcinoma treated with mastectomy and doxorubicin-based chemotherapy without trastuzumab and without irradiation with a median follow-up of 12.5 years. A wide range of HER2 expression (HER2 ≥1+) in the primary tumor was significantly associated with decreased locoregional recurrence-free survival (P=0.014), decreased disease-specific survival (P=0.001), and decreased overall survival (P=0.001). Even in the subset considered HER2 negative by current College of American Pathologists and American Society of Clinical Oncology guidelines, HER2=1+ was associated with worse outcome than HER2=0 in this patient cohort. The association between HER2 ≥1+ and worse outcome had the greatest statistical significance in the hormone receptor-positive subset of patients. These findings support the hypothesis that low-level HER2 expression may have significant clinical implications. Although the assessment of HER2 expression is most important for predicting response to anti-HER2 therapy, detection of low-level HER2 expression might also be useful in helping to select a more aggressive treatment regimen for patients ineligible for anti-HER2 therapy.

Loss of myoepithelium is variable in solid papillary carcinoma of the breast.

Aims:  Reports on the frequency of myoepithelial loss in solid papillary carcinoma (SPC) of the breast, an unusual variant of papillary carcinoma with a solid pattern of expansile growth, have been strikingly contradictory. The aim was to clarify the frequency of myoepithelial loss in cases of SPC diagnosed at our institution.

Pleomorphic and dedifferentiated leiomyosarcoma: clinicopathologic and immunohistochemical study of 41 cases

In this article, we supplement the few published articles by describing the clinical and pathologic features of pleomorphic and dedifferentiated leiomyosarcoma from 41 patients (27 women and 14 men) with an age range of 25 to 75 years (mean, 56.5 years), representing the largest cohort reported to date. The typical leiomyosarcoma component accounted for <5% to 60% (mean, 15%) of the tumor. The pleomorphic sarcoma component was composed of polygonal cells in 57% of cases, spindle cells in 21%, a combination of polygonal, epithelioid, rhabdoid, and/or spindle cells in 18%, and predominantly epithelioid cells in 3%. The classical leiomyosarcoma component was positive for at least one myogenic immunohistochemical marker in 29 tumors tested; smooth muscle actin in 100% (27/27), calponin in 90% (9/10), muscle-specific actin in 90% (10/11), desmin in 86% (23/27), smooth muscle myosin heavy chain (SMMS-1) in 67% (4/6), and caldesmon in 57% (4/7). The pleomorphic sarcoma component was reactive for at least one muscle marker in 77% (23/30) of cases; smooth muscle actin in 63% (17/27), calponin in 60% (6/10), SMMS-1 in 60% (3/5), desmin in 59% (16/27), muscle-specific actin in 40% (4/10), and caldesmon in 29% (2/7). The classical leiomyosarcoma component was often strongly positive for myogenic markers, and the pleomorphic sarcoma component usually showed focal and less intense immunoreactivity. Based on staining for muscle markers in the pleomorphic component, twenty-three cases were designated as pleomorphic leiomyosarcoma, and 7 cases were designated as dedifferentiated leiomyosarcoma (negative for all muscle markers used). Eleven cases, in which tissue was not available for immunhistochemical stains, the question of pleomorphic versus dedifferentiated leiomyosarcoma could not be answered. The incidence of metastasis was 89% (32/36) and the mortality rate was 50% (18/36) at last follow-up (3-104 months; mean, 27.5 months).

Coexpression of α6β4 Integrin and Guanine Nucleotide Exchange Factor Net1 Identifies Node-Positive Breast Cancer Patients at High Risk for Distant Metastasis

Preclinical data indicate that α6β4 integrin signaling through Ras homolog gene family, member A, plays an important role in tumor cell motility. The objective of this study was to determine whether the combined expression of α6β4 integrin and neuroepithelioma transforming gene 1 (Net1), a guanine nucleotide exchange factor specific for Ras homolog gene family member A, is associated with adverse clinical outcome in breast cancer patients. Immunohistochemical expression of each protein was evaluated in a tumor tissue microarray prepared from the primary tumors of 94 node-positive patients with invasive breast carcinoma treated with total mastectomy and doxorubicin-based chemotherapy without radiation with a median follow-up of 12.5 years. Associations between staining results and multiple clinicopathologic variables were investigated. Although there was no significant association between α6β4 integrin or Net1 expression and clinical outcome when each marker was considered individually, coexpression of α6β4 and Net1 was associated with decreased distant metastasis–free survival (P = 0.030). In the subset of patients with hormone receptor–positive tumors, coexpression of α6β4 and Net1 was associated with a decrease in distant metastasis–free and overall survival (P < 0.001 and P = 0.006, respectively). Although an association between human epidermal growth factor receptor 2 expression and coexpression of α6β4 and Net1 (P = 0.008) was observed, coexpression of α6β4 and Net1 (hazard ratio, 1.63; P = 0.02) and lymphovascular invasion (hazard ratio, 2.35; P = 0.02) were the only factors independently associated with the development of distant metastasis in multivariate analysis. These findings suggest that coexpression of α6β4 integrin and Net1 could be a useful biomarker for aggressive disease in node-positive breast cancer patients. (Cancer Epidemiol Biomarkers Prev 2009;18(1):80–6)

Pulmonary Metastasis From Liposarcoma A Clinicopathologic and Immunohistochemical Study of 24 Cases

A review of the histologic features of pulmonary metastasis and clinical implications of liposarcoma (LS) is given for 24 cases (8 each) of the 3 types of LS: myxoid LS (ML), pleomorphic LS (PL), and dedifferentiated LS (DDL). Most patients were men. Metastatic ML and PL were distributed almost equally among the lung lobes, whereas DDL was more common in the left lower lobe. The metastatic MLs had variable cellularity ranging from singly scattered cells in a hyalinized stroma (treatment-related effect) to hypercellular ML. Most PLs (6/8) were nonlipogenic and resembled an undifferentiated pleomorphic sarcoma. All metastatic DDLs had high-grade histologic features and were predictably nonlipogenic. After pulmonary metastasectomy, 2 patients with ML and 1 with PL were disease-free. The other 6 patients with ML, 7 with PL, and all with DDL had progressive disease. The morphologic features of LS metastatic to the lungs seem diverse but within the spectrum of the histologic type expected from the primary tumor. Overall, the general trend for these LS subsets is progressive disease, metastatic disease for ML and PL with a much shorter interval for PL, and metastatic disease and local recurrence for DDL.

A model for the design and construction of a resource for the validation of prognostic prostate cancer biomarkers: the Canary Prostate Cancer Tissue Microarray

Tissue microarrays (TMAs) provide unique resources for rapid evaluation and validation of tissue biomarkers. The Canary Foundation Retrospective Prostate Tissue Microarray Resource used a rigorous statistical design, quota sampling, a variation of the case-cohort study, to select patients for inclusion in a multicenter, retrospective prostate cancer TMA cohort. The study is designed to definitively validate tissue biomarkers of prostate cancer recurrence after radical prostatectomy. Tissue samples from over 1000 participants treated for prostate cancer with radical prostatectomy between 1995 and 2004 were selected at 6 participating institutions in the United States and Canada. This design captured the heterogeneity of screening and clinical practices in the contemporary North American population. Standardized clinical data were collected in a centralized database. The project has been informative in several respects. The scale and complexity of assembling TMAs with over 200 cases at each of 6 sites involved unanticipated levels of effort and time. Our statistical design promises to provide a model for outcome-based studies where tissue localization methods are applied to high-density TMAs.

Gleason grade-based automatic classification of prostate cancer pathological images

In this Paper, we introduce a new method for automatic recognition and classification of prostate cancer biopsy images based on Gleason grading system. The introduced algorithm combines features from wavelet transform and fractal analysis domains. Biopsy images are pre-processed prior to features extraction using effective image processing algorithms to analyze textural complexity in terms of RGB color channels, edge and segmentation information. Experimental results achieved an average classification accuracy of 95 % in a set of 45 images with diversities in resolution, magnification levels, and stain colors.

Mediastinal rhabdomyoma: a case report and review of the literature.

An incidental anterior-superior mediastinal rhabdomyoma is reported in a 68-year-old man who died of hypovolemic shock as a result of massive blood loss due to transection of aorta after being hit by a moving motor vehicle. This is the third reported case of mediastinal rhabdomyoma in the literature. The immunohistochemical evidence of expression of muscle-specific markers supports the rhabdomyomatous nature of this neoplasm, and electron microscopic demonstration of haphazardly arranged myofilaments with prominent Z bands, “jack-straws” in the mitochondria, and the absence of desmosomes is supportive of extracardiac origin of this rhabdomyoma. The possible histogenesis of extracardiac adult rhabdomyoma (EAR) in the anterior-superior mediastinum from the thymic myoid cells is also discussed.

Micropapillary carcinoma of the urinary bladder: Report of a case and review of its cytologic features

Micropapillary carcinoma (MPC) is an aggressive variant of urothelial carcinoma. MPC has a propensity to invade lymphovascular spaces and detrusor muscle early in the disease that often leads to upstaging and/or lymph node metastasis in many cases at cystectomy. Its association with the usual high‐grade urothelial carcinoma provides an easy recognition of malignancy in cytology specimens without attempt at separating or identifying the MPC component. This may be related to our limited familiarity of its cytologic features with only 4 cases described in the literature. We report another case of MPC and highlight its features in cytologic preparations including the presence of singly scattered tumor cells with high nuclear to cytoplasmic ratio and pleomorphic nuclei, clustered cells devoid of fibrovascular core (micropapillae), 3‐dimensional cell aggregates, cytoplasmic vacuoles, and micropapillae exhibiting some features of low‐grade urothelial neoplasm. Appreciation of these features may help facilitate its early diagnosis and hopefully a better outcome for these aggressive tumors. Diagn. Cytopathol. 2010.