Nottingham-defined mitotic score: comparison with visual and image cytometric phosphohistone H3 labeling indices and correlation with Oncotype DX recurrence score.

Prognosis of breast cancer patients has been determined traditionally by lymph node status, tumor size, and histologic grade. In recent years the Oncotype DX recurrence score (RS) assay has emerged as an expensive adjunct prognostic tool. Markers of proliferation play a large role in determination of RS, and we have shown previously that immunohistochemical expression of proliferation markers Ki-67 and phosphohistone H3 (PPH3) correlates with RS. Our current goal is comparison of the hematoxylin and eosin (H&E) mitotic score, defined by the Nottingham grading system, with anti-PPH3 mitotic figure labeling assessed by both visual and automated image analysis and correlation of mitotic score results with RS. Estrogen receptor-positive breast carcinomas from 137 patients with Oncotype DX testing were selected. A representative H&E-stained tumor section was evaluated. Mitoses were counted per 10 high-power fields and tumors graded using the Nottingham criteria by 1 pathologist in accordance with College of American Pathologists-recommended mitotic count cutoffs for a field diameter of 0.55 mm. An additional section was immunostained with PPH3 antibody. PPH3 mitotic scores were determined visually and by automated imaging system. Statistical analysis was performed using univariate tests and Spearman coefficient. There was a statistically significant positive correlation among the 3 methods of mitotic score assessment. Specifically, correlation of tumor grades obtained using visual and automated methods of assessment of mitotic activity with PPH3 stain was the strongest and most statistically significant (weighted κ value 0.84, P<0.001; Spearman coefficient 0.89, P<0.001). There was a statistically significant positive correlation between H&E mitosis score and RS (P<0.001, Spearman coefficient 0.30) and between visual PPH3 mitotic score and RS (P<0.001, Spearman coefficient 0.28). In conclusion, mitotic score by any of the 3 methods studied may be useful in assessing tumor grade, proliferation, and prognosis.

Protein-coding and microRNA biomarkers of recurrence of prostate cancer following radical prostatectomy.

An important challenge in prostate cancer research is to develop effective predictors of tumor recurrence following surgery to determine whether immediate adjuvant therapy is warranted. To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed, paraffin-embedded radical prostatectomy specimens with known long-term outcomes to perform DASL expression profiling with a custom panel that we designed of 522 prostate cancer-relevant genes. We identified a panel of 10 protein-coding genes and two miRNA genes (RAD23B, FBP1, TNFRSF1A, CCNG2, NOTCH3, ETV1, BID, SIM2, LETMD1, ANXA1, miR-519d, and miR-647) that could be used to separate patients with and without biochemical recurrence (P < 0.001), as well as for the subset of 42 Gleason score 7 patients (P < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of biochemical recurrence for all cases (P = 0.013) and for a subset of 19 Gleason score 7 cases (P = 0.010), both of which were adjusted for relevant clinical information including T-stage, prostate-specific antigen, and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason score 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens.

Proliferation (Ki-67 and phosphohistone H3) and oncotype DX recurrence score in estrogen receptor-positive breast cancer.

The Oncotype DX Recurrence Score (RS) is often used in lymph node-negative, estrogen receptor-positive breast cancer to refine prognosis and direct therapy. Its utility is limited by its cost, proprietary nature, and turnaround time. Markers of proliferation factor heavily into determination of RS. Our aim is to correlate expression of proliferation markers Ki-67 and phosphohistone H3 (PPH3) with RS and other prognostic indicators. Estrogen receptor-positive invasive breast carcinomas from 133 patients with Oncotype DX testing were selected. Representative tumor sections were stained with MIB1, a monoclonal antibody that reacts against Ki-67, and antibody to PPH3. Nuclear staining was quantitated through an automated imaging system. The percentage of positive cells was scored as low (<10%), intermediate (10% to 20%), or high (>20%) for Ki-67, and low (<2%), intermediate (2% to 5%), or high (>5%) for PPH3. Expression of both markers was compared with RS and clinicopathologic parameters including grade, tumor size, lymph node metastasis, and angiolymphatic invasion. Ki-67 and PPH3 expression were both significantly associated with RS (P=0.02 and P=0.027, respectively) and grade (P<0.001 and P=0.002, respectively). Ki-67 expression correlated with angiolymphatic invasion (P=0.01) but not with tumor size or lymph node metastasis; PPH3 expression showed no association with any of these 3 parameters. Expression of proliferation markers Ki-67 and PPH3 by immunohistochemistry is significantly correlated with RS and tumor grade. This observation suggests that immunohistochemical assessment of markers of proliferation may provide useful prognostic information, at lower cost than RS testing.

Triple-negative breast carcinoma in women from Vietnam and the United States: characterization of differential marker expression by tissue microarray.

Triple-negative breast carcinoma accounts for approximately 15% of all breast cancers. It is characterized by an aggressive clinical history, high rate of local relapse, and association with the basal epithelial-like subtype. Variations in breast cancer subtype and clinical outcome often exist across racial and ethnic lines. Therefore, the aim of this study was to compare the immunohistochemical and clinicopathologic characteristics of triple-negative breast carcinoma in women living in Vietnam with those from the United States. Invasive triple-negative breast carcinoma of patients from the 2 populations was characterized by tissue microarray for the expression of basal cytokeratins (CK5/6, CK7, CK14), luminal cytokeratins (CK8, CK18, CK19), and markers associated with the basal phenotype (cKit, epithelial growth factor receptor, P-cadherin, p53, and p63). Significant differences in expression between the 2 populations were not observed for the basal cytokeratins. However, epithelial growth factor receptor and P-cadherin, markers associated with the basal phenotype, were underexpressed in Vietnamese patients. Of the luminal cytokeratins, CK8 was overexpressed and CK18 was underexpressed in the Vietnamese women. Significant differences were also observed regarding the clinicopathologic characteristics. Triple-negative breast carcinoma in Vietnamese women was smaller and less likely to be grade III. In addition, it was more frequently of ductal histologic type and less often medullary or metaplastic. These differences in histology and marker expression suggest that triple-negative breast carcinoma has unique biological characteristics in women from Vietnam and the United States, and may follow a unique clinical course in each of the 2 populations.