Anti-Phosphohistone H3-Positive Mitoses Are Linked to Pathological Response in Neoadjuvantly Treated Breast Cancer

Can Mitotic Figures in Hyperchromatic Crowded Groups be Cytodiagnostic Criteria for High-Grade Squamous Intra-epithelial Lesions?

Aims

The present study aimed to investigate whether the presence of mitoses in hyperchromatic crowded groups (HCGs) in cervical cytological specimens can serve as cytological criteria for high-grade squamous intra-epithelial lesions (HSILs).

Methods and Material

Various parameters were examined, including the frequency of mitotic figures per high power field (HPF) in Pap, hematoxylin eosin (HE) samples, and PHH3 immunocytochemical (ICC) and immunohistochemical (IHC) analyses.

Results

In the Pap and PHH3-ICC samples, the number of mitotic figures observed in HCGs was significantly higher in HSIL (P < 0.001) compared to other groups. Furthermore, the frequency of observing two or more mitoses was significantly higher in HSIL (Pap: P = 0.002, PHH3-ICC: P < 0.001) than in low-grade squamous intra-epithelial lesions (LSILs). Moreover, a comparison between Pap samples and PHH3-ICC showed that the frequency of two or more mitoses was significantly higher in the PHH3-ICC analysis of HSIL (P = 0.042). Regarding HE and PHH3-IHC samples, counting the number of mitoses in the lower and middle/upper layers of the squamous epithelial layer revealed that HSIL had a significantly higher value (HE: P = 0.0089, PHH3-IHC: P = 0.0002) than LSIL in the middle/upper layers.

Conclusions

Hence, the presence of two or more mitotic figures in HCGs per HPF in cervical cytology indicates a suspicion of HSIL. The detection of mitoses in PHH3-ICC samples is more sensitive and easier to observe than in Pap samples, making it a valuable mitotic marker.

Deep learning based registration of serial whole-slide histopathology images in different stains

For routine pathology diagnosis and imaging-based biomedical research, Whole-slide image (WSI) analyses have been largely limited to a 2D tissue image space. For a more definitive tissue representation to support fine-resolution spatial and integrative analyses, it is critical to extend such tissue-based investigations to a 3D tissue space with spatially aligned serial tissue WSIs in different stains, such as Hematoxylin and Eosin (H&E) and Immunohistochemistry (IHC) biomarkers. However, such WSI registration is technically challenged by the overwhelming image scale, the complex histology structure change, and the significant difference in tissue appearances in different stains. The goal of this study is to register serial sections from multi-stain histopathology whole-slide image blocks. We propose a novel translation-based deep learning registration network CGNReg that spatially aligns serial WSIs stained in H&E and by IHC biomarkers without prior deformation information for the model training. First, synthetic IHC images are produced from H&E slides through a robust image synthesis algorithm. Next, the synthetic and the real IHC images are registered through a Fully Convolutional Network with multi-scaled deformable vector fields and a joint loss optimization. We perform the registration at the full image resolution, retaining the tissue details in the results. Evaluated with a dataset of 76 breast cancer patients with 1 H&E and 2 IHC serial WSIs for each patient, CGNReg presents promising performance as compared with multiple state-of-the-art systems in our evaluation. Our results suggest that CGNReg can produce promising registration results with serial WSIs in different stains, enabling integrative 3D tissue-based biomedical investigations.

Improving mitotic cell counting accuracy and efficiency using phosphohistone-H3 (PHH3) antibody counterstained with haematoxylin and eosin as part of breast cancer grading

BACKGROUND

Mitotic count in breast cancer is an important prognostic marker. Unfortunately, substantial inter- and intraobserver variation exists when pathologists manually count mitotic figures. To alleviate this problem, we developed a new technique incorporating both haematoxylin and eosin (H&E) and phosphorylated histone H3 (PHH3), a marker highly specific to mitotic figures, and compared it to visual scoring of mitotic figures using H&E only.

METHODS

Two full-face sections from 97 cases were cut, one stained with H&E only, and the other was stained with PHH3 and counterstained with H&E (PHH3-H&E). Counting mitoses using PHH3-H&E was compared to traditional mitoses scoring using H&E in terms of reproducibility, scoring time, and the ability to detect mitosis hotspots. We assessed the agreement between manual and image analysis-assisted scoring of mitotic figures using H&E and PHH3-H&E-stained cells. The diagnostic performance of PHH3 in detecting mitotic figures in terms of sensitivity and specificity was measured. Finally, PHH3 replaced the mitosis score in a multivariate analysis to assess its significance.

RESULTS

Pathologists detected significantly higher mitotic figures using the PHH3-H&E (median ± SD, 20 ± 33) compared with H&E alone (median ± SD, 16 ± 25), P < 0.001. The concordance between pathologists in identifying mitotic figures was highest when using the dual PHH3-H&E technique; in addition, it highlighted mitotic figures at low power, allowing better agreement on choosing the hotspot area (k = 0.842) in comparison with standard H&E (k = 0.625). A better agreement between image analysis-assisted software and the human eye was observed for PHH3-stained mitotic figures. When the mitosis score was replaced with PHH3 in a Cox regression model with other grade components, PHH3 was an independent predictor of survival (hazard ratio [HR] 5.66, 95% confidence interval [CI] 1.92-16.69; P = 0.002), and even showed a more significant association with breast cancer-specific survival (BCSS) than mitosis (HR 3.63, 95% CI 1.49-8.86; P = 0.005) and Ki67 (P = 0.27).

CONCLUSION

Using PHH3-H&E-stained slides can reliably be used in routine scoring of mitotic figures and integrating both techniques will compensate for each other's limitations and improve diagnostic accuracy, quality, and precision.

Utility of PHH3 in Evaluation of Mitotic Index in Breast Carcinoma and Impact on Tumor Grade

Background:

Mitotic activity index is considered as the most important grading component to predict prognosis in invasive breast carcinoma. But it is believed that it is also the cause of discordance in grade estimation based on Bloom-Richardson system. Thus, reproducible methods such as immunohistochemistry (IHC) based analysis methods appears to be of great value in facilitating mitotic count.

Materials and Methods:

In the present study, we examined the utility of Phosphohistone H3 by IHC in various grades of breast carcinoma and compared it with traditional mitotic count by hematoxylin and eosin (H and E) staining and probable changes in tumor grading.

Results:

Total 90 cases of invasive breast carcinoma were evaluated. Mean mitotic count were 8.6 and 6.4/10HPF in IHC and HandE groups, respectively. Although , mean average count was higher by IHC method , good correlation was observed(R=0.914). Using PHH3 IHC, two out of 33 cases of grade I tumors were upgraded in to grade II and three cases of grade II were upgraded in to grade III. None of the tumors were down graded.

Conclusion:

Similar to some other previous studies, we found PHH3 a robust sensitive and practical marker for mitotic count in breast carcinoma. Especially it is helpful to identify the most proliferating area. However, further studies are required to confirm the superiority of this biomarker for including in grading system.

Evaluation of phospho-histone H3 in Asian triple-negative breast cancer using multiplex immunofluorescence

PURPOSE

We used multiplex immunofluorescence (mIF) to determine whether mitotic rate represents an independent prognostic marker in triple-negative breast cancer (TNBC). Secondary aims were to confirm the prognostic significance of immune cells in TNBC, and to investigate the relationship between immune cells and proliferating tumour cells.

METHODS

A retrospective Asian cohort of 298 patients with TNBC diagnosed from 2003 to 2015 at the Singapore General Hospital was used in the present study. Formalin-fixed, paraffin-embedded breast cancer samples were analysed on tissue microarrays using mIF, which combined phospho-histone H3 (pHH3) expression with cytokeratin (CK) and leukocyte common antigen (CD45) expression to identify tumour and immune cells, respectively.

RESULTS

Multivariate analysis showed that a high pHH3 index was associated with significantly improved overall survival (OS; p = 0.004), but this was not significantly associated with disease-free survival (DFS; p = 0.22). Similarly, multivariate analysis also revealed that a pHH3 positive count of > 1 cell per high-power field in the malignant epithelial compartment was an independent favourable prognostic marker for OS (p = 0.033) but not for DFS (p = 0.250). Furthermore, a high CD45 index was an independent favourable prognostic marker for DFS (p = 0.018), and there was a significant positive correlation between CD45 and pHH3 index (Spearman rank correlation coefficient, 0.250; p < 0.001).

CONCLUSIONS

Mitotic rates as determined by pHH3 expression in epithelial cells are significantly associated with improved survival in TNBC. mIF analysis of pHH3 in combination with CK and CD45 could help clinicians in prognosticating patients with TNBC.