The Long-term Prognostic Performance of Ki-67 in Primary Operable Breast Cancer and Evaluation of Its Optimal Cutoff Value

Optimizing ultrafast dynamic contrast-enhanced MRI scan duration in the differentiation of benign and malignant breast lesions

OBJECTIVE

To determine the optimal scan duration for ultrafast DCE-MRI in effectively differentiating benign from malignant breast lesions.

METHODS

The study prospectively recruited participants who underwent breast ultrafast DCE-MRI from September 2021 to March 2023. A 30-phase breast ultrafast DCE-MRI on a 3.0-T MRI system was conducted with a 4.5-s temporal resolution. Scan durations ranged from 40.5 s to 135.0 s, during which the analysis is performed at three-phase intervals, forming eight dynamic sets (scan duration [SD]40.5s: 40.5 s, SD54s: 54.0 s, SD67.5s: 67.5 s, SD81s: 81.0 s, SD94.5s: 94.5 s, SD108s: 108.0 s, SD121.5s: 121.5 s, and SD135s: 135.0 s). Two ultrafast DCE-MRI parameters, maximum slope (MS) and initial area under the curve in 60 s (iAUC), were calculated for each dynamic set and compared between benign and malignant lesions. Areas under the receiver operating characteristic curve (AUCs) were used to assess their diagnostic performance.

RESULTS

A total of 140 women (mean age, 47 ± 11 years) with 151 lesions were included. MS and iAUC from eight dynamic sets exhibited significant differences between benign and malignant lesions (all p < 0.05), except iAUC at SD40.5s. The AUC of MS (AUC = 0.804) and iAUC (AUC = 0.659) at SD67.5s were significantly higher than their values at SD40.5s (AUC = 0.606 and 0.516; corrected p < 0.05). No significant differences in AUCs for MS and iAUC were observed from SD67.5s to SD135s (all corrected p > 0.05).

CONCLUSIONS

Ultrafast DCE-MRI with a 67.5-s scan duration appears optimal for effectively differentiating malignant from benign breast lesions.

CRITICAL RELEVANCE STATEMENT

By evaluating scan durations (40.5-135 s) and analyzing two ultrafast DCE-MRI parameters, we found a scan duration of 67.5 s optimal for discriminating between these lesions and offering a balance between acquisition time and diagnostic efficacy.

KEY POINTS

Ultrafast DCE-MRI can effectively differentiate malignant from benign breast lesions. A minimum of 67.5-sec ultrafast DCE-MRI scan duration is required to differentiate benign and malignant lesions. Extending the scan duration beyond 67.5 s did not significantly improve diagnostic accuracy.

Early prediction of pathologic complete response of breast cancer after neoadjuvant chemotherapy using longitudinal ultrafast dynamic contrast-enhanced MRI

PURPOSE

The purpose of this study was to evaluate the temporal trends of ultrafast dynamic contrast-enhanced (DCE)-MRI during neoadjuvant chemotherapy (NAC) and to investigate whether the changes in DCE-MRI parameters could early predict pathologic complete response (pCR) of breast cancer.

MATERIALS AND METHODS

This longitudinal study prospectively recruited consecutive participants with breast cancer who underwent ultrafast DCE-MRI examinations before treatment and after two, four, and six NAC cycles between February 2021 and February 2022. Five ultrafast DCE-MRI parameters (maximum slope [MS], time-to-peak [TTP], time-to-enhancement [TTE], peak enhancement intensity [PEI], and initial area under the curve in 60 s [iAUC]) and tumor size were measured at each timepoint. The changes in parameters between each pair of adjacent timepoints were additionally measured and compared between the pCR and non-pCR groups. Longitudinal data were analyzed using generalized estimating equations. The performance for predicting pCR was assessed using area under the receiver operating characteristic curve (AUC).

RESULTS

Sixty-seven women (mean age, 50 ± 8 [standard deviation] years; age range: 25-69 years) were included, 19 of whom achieved pCR. MS, PEI, iAUC, and tumor size decreased, while TTP increased during NAC (all P < 0.001). The AUC (0.92; 95% confidence interval [CI]: 0.83-0.97) of the model incorporating ultrafast DCE-MRI parameter change values (from timepoints 1 to 2) and clinicopathologic characteristics was greater than that of the clinical model (AUC, 0.79; 95% CI: 0.68-0.88) and ultrafast DCE-MRI parameter model at timepoint 2 when combined with clinicopathologic characteristics (AUC, 0.82; 95% CI: 0.71-0.90) (P = 0.01 and 0.02).

CONCLUSION

Early changes in ultrafast DCE-MRI parameters after NAC combined with clinicopathologic characteristics could serve as predictive markers of pCR of breast cancer.

Identifying the optimal cutoff point of Ki-67 in breast cancer: a single-center experience

OBJECTIVE

Ki-67 is associated with breast cancer subtypes, but the optimal cutoff point of Ki-67 has not been established in our center. We evaluated the cutoff point of Ki-67 in breast cancer and analyzed the associations among Ki-67, clinicopathological features, and prognosis.

METHODS

The clinicopathological data and prognostic information of patients with breast cancer treated in our center were retrospectively collected, and the optimal cutoff point of Ki-67 was determined by univariate and multivariate survival risk analyses. The cutoff point was used to group the patients, and the differences in the clinicopathological features and prognosis were analyzed between the two groups.

RESULTS

In total, 609 patients with estrogen receptor-positive and human epidermal growth factor receptor 2-negative primary breast cancer were enrolled. The mean Ki-67 value was 22.3% ± 15.4%, the median was 20%, and a cutoff point of 30% was an independent factor influencing recurrence-free survival. When 30% was used as the cutoff point, patients with a Ki-67 value of ≤30% had a better prognosis and lower tumor malignancy.

CONCLUSION

The optimal cutoff point of Ki-67 in breast cancer in our center is 30%.

The Potential Value of Ki-67 in Prognostic Classification in Early Low-Risk Endometrial Cancer

PURPOSE

This study aims to determine the optimal cut-off value of Ki-67 to better predict the recurrence of early low-risk endometrial cancer (EC).

METHODS

Seven hundred and forty-eight patients diagnosed with low-risk EC from West China Second Hospital of Sichuan University and the First Affiliated Hospital of Chongqing Medical University were retrospectively analyzed. The receiver operating characteristic curve (ROC) and Youden index were used to calculate the optimal cut-off value of Ki-67 expression. The clinicopathological indexes between two groups divided by cut-off value of Ki-67 were compared. The univariate and multivariate regression analyses were performed to investigate risk factors connected to the recurrence of early low-risk EC. The survival analysis was shown in Kaplan-Meier curve.

RESULT

Thirty-three patients were detected with tumor recurrence after primary surgery (4.4%); 33% was the optimal cut-off value of the Ki-67 index. A high Ki-67 was significantly associated with age (P = .002), myometrial invasion (P < .001), and the expression of P53 (P = .007). The multivariate regression analysis verified that Ki67 ≥ 33% was an independent prognostic factor for predicting recurrence. The recurrence-free survival (RFS) and the overall survival (OS) in high Ki-67 group was significantly lower than that in low Ki-67 group (P < .001 and P = .029, respectively). The prognostic values of ER, PR, and P53 in combination with Ki-67 were superior to each single predictor.

CONCLUSIONS

The optimal cut-off value of Ki-67 for predicting recurrence is 33%, which quantitatively defines the specific value of Ki-67 that causes high-risk recurrence in early low-risk EC.

CD47 expression and tumor-associated immune cells in breast cancer and their correlation with molecular subtypes and prognostic factors

OBJECTIVE

Breast cancer is the most common malignancy in women and a heterogeneous disease at the molecular level. Since most breast cancer cases are not of a special type, it is suggested that tumor-associated macrophages and tumor-infiltrating lymphocytes, which are involved in tumor growth, invasion, angiogenesis, and metastasis, may be important factors that should be evaluated together with standard criteria to determine the prognosis of cancer and assist in treatment decisions and outcome stratification. In this study, CD47 expression, which is involved in macrophage-mediated immune escape, tumor-infiltrating lymphocytes, and tumor-associated macrophages were evaluated in breast cancer molecular subgroups and correlated with prognostic factors.

MATERIAL AND METHOD

The immunohistochemistry of CD47, CD163, and CD3 was analyzed on the tissue microarrays of 278 invasive breast cancer cases.

RESULTS

The CD47, CD163, and CD3 expressions were found to be correlated with various clinicopathological parameters in breast cancer. High levels of CD47, CD163, and CD3 expressions had a significant correlation with the ER status and PR status, Ki-67 proliferation index, and molecular subtype (P < 0.05). The CD47 expression had a significant correlation with the CD3 and CD163 expressions (p = 0.021 and p = 0.001, respectively).

CONCLUSIONS

Our results suggest that CD47, CD163, and CD3 may be among the prognostic factors of breast cancer. The combined use of CD47, CD163, and CD3 can be a new prognostic factor for patients with breast cancer, especially as a therapeutic target in hormone receptor-negative breast cancer cases and those with a high proliferation index.

The combined ratio of estrogen, progesterone, Ki-67, and P53 to predict the recurrence of endometrial cancer

BACKGROUND AND OBJECTIVES

We aimed to explore the capacity of the combined ratio of biomarkers to predict the recurrence of Stage I-III endometrial cancer (EC).

METHODS

A total of 473 patients were enrolled after screening. The cut-off value of the ratio was calculated by the receiver operating characteristic curve (ROC). The univariate and multivariate Cox regression analysis was used to assess the correlation between the combined ratio and the recurrence of EC. The differences of clinicopathological parameters between the two groups divided based on the threshold were compared.

RESULT

The ROC curve showed that 0.92 was the optimal cut-off value of the ratio ([ER + PR]/[P53 + Ki67]). The multivariate analysis demonstrated that only International Federation of Gynecology and Obstetrics stage (p = .031) and the combined ratio (p = .004) were independent risk factors of recurrence. The 3-year recurrence-free survival (RFS) and overall survival of patients in the low-ratio group were 54.1% and 66.8%, respectively; while in the high-ratio group were 94.9% and 97.9%, respectively (p < .001). The 3-year RFS of 194 patients, who did not receive the adjuvant therapy, was 54.7% and 97.2% between two groups (p < .001).

CONCLUSIONS

The optimal cut-off value (0.92) of the combined ratio was demonstrated to be better to predict the recurrence of EC than a single immunohistochemical marker.

Analysis of the molecular subtypes of preoperative core needle biopsy and surgical specimens in invasive breast cancer

Background

Accurate molecular classification of breast core needle biopsy (CNB) tissue is important for determining neoadjuvant systemic therapies for invasive breast cancer. The researchers aimed to evaluate the concordance rate (CR) of molecular subtypes between CNBs and surgical specimens.

Methods

This study was conducted with invasive breast cancer patients who underwent surgery after CNB at Seoul St. Mary’s Hospital between December 2014 and December 2017. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki67 were analyzed using immunohistochemistry. ER and PR were evaluated by Allred score (0–8). HER2 was graded from 0 to +3, and all 2+ cases were reflex tested with silver in situ hybridization. The labeling index of Ki67 was counted by either manual scoring or digital image analysis. Molecular subtypes were classified using the above surrogate markers.

Results

In total, 629 patients were evaluated. The CRs of ER, PR, HER2, and Ki67 were 96.5% (kappa, 0.883; p<.001), 93.0% (kappa, 0.824; p<.001), 99.7% (kappa, 0.988; p<.001), and 78.7% (kappa, 0.577; p<.001), respectively. Digital image analysis of Ki67 in CNB showed better concordance with Ki67 in surgical specimens (CR, 82.3%; kappa, 0.639 for digital image analysis vs. CR, 76.2%; kappa, 0.534 for manual counting). The CRs of luminal A, luminal B, HER2, and triple negative types were 89.0%, 70.0%, 82.9%, and 77.2%, respectively.

Conclusions

CNB was reasonably accurate for determining ER, PR, HER2, Ki67, and molecular subtypes. Using digital image analysis for Ki67 in CNB produced more accurate molecular classifications.

Correlation of proliferative index with various clinicopathologic prognostic parameters in primary breast carcinoma: A study from North India

Aim

Routine assessment of cell proliferation is recommended in the pathologic evaluation for all breast cancers. Considering the poor reproducibility and interobserver variability in mitotic counts, Ki-67 is an easily available and reliable substitute for mitotic counts and has been shown to have a significant relationship with the histologic grade of malignancy and the mitotic activity of tumors. Our study aimed at exploring Ki-67 expression and studying its correlation with other established prognostic parameters.

Materials and Methods

Seventy-five cases of primary breast cancer undergoing radical or modified radical mastectomy constituted the study group. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2)/neu, and Ki-67 was assessed in each case. Ki-67 labeling index (Ki-67-LI) was estimated as the number of positive nuclei divided by total number of nuclei scanned counting a minimum of 1000 cells in 10 selected high power fields that displayed the highest immunoreactivity and was expressed as percentage. Ki-67 expression was correlated with various clinicopathologic prognostic parameters including age, tumor size, tumor type, axillary lymph node status, and histologic tumor grade.

Results

A statistically significant direct association was observed between Ki-67-LI and tumor size, histologic grade and Nottingham prognostic index. A statistically significant inverse association was observed between Ki-67-LI and ER and PR expression. However, no association was observed between Ki-67-LI and menopausal status, lymph node involvement and HER2/neu expression.

Conclusion

Based on our results, we concluded that modified Bloom-Richardson (MBR) grading has been recognized as a treatment related indicator. The accuracy and reliability in grading have always been a matter of concern, hence, the reproducibility of grading should be enhanced. Ki-67-a proliferation marker is easily identified and provides comparable accurate information. In contrast to poor reproducibility of mitotic counts, Ki-67 can achieve high agreement between pathologists; is more reproducible; adds complementary value to the MBR grading system and correlates well with other clinicopathologic parameters. It may act as a significant prognostic indicator for routine clinical use and be helpful for selection of adjuvant treatment. It can also add value in categorizing Grade II tumors into two prognostic subgroups with prognosis equivalent to Grades I and III, respectively.

ADC at 3.0 T as a noninvasive biomarker for preoperative prediction of Ki67 expression in invasive ductal carcinoma of breast

PURPOSE

To investigate the role of apparent diffusion coefficient (ADC) as an imaging biomarker for invasive ductal carcinoma (IDC) in the breast.

METHODS

Seventy-one patients undergoing 3.0 Tesla DWI were retrospectively enrolled. Correlations between the ADC values and prognostic factors were evaluated.

RESULTS

Multivariate regression analyses showed that Ki67 expression and molecular subtype were independently associated with the ADC. Discriminant analysis excluded the ADC as a good biomarker for subtype, but the mean ADC significantly distinguished Ki67-positive (low ADC) from Ki67-negative (high ADC) lesions, as observed in the in ROC curves, with a diagnostic sensitivity of 1.00 and a cut-off value of 0.97 × 10^-3 mm²/s.

CONCLUSION

The ADC may be helpful for predicting Ki67 expression in IDC preoperatively.

Clinical usefulness of the free web-based image analysis application ImmunoRatio for assessment of Ki-67 labelling index in breast cancer

Aims

Ki-67 is a prognostic marker in breast cancer; however, the use of the Ki-67 labelling index (LI) in clinical practice requires a consistent and easily accessible scoring method. The present study evaluated the use of the free internet-based image analysis program ImmunoRatio to score Ki-67 LI in breast cancer in comparison with manual counting.

Methods

Ki-67 immunohistochemical detection was performed in 577 breast cancer cases, and the Ki-67 LI was determined by ImmunoRatio and manual counting.

Results

The Ki-67 LI determined by ImmunoRatio correlated well with that obtained by manual counting. The concordance rate between ImmunoRatio and manual counting was excellent (κ coefficient of 0.881) at a Ki-67 LI cut-off value of 20%. Cases with high Ki-67 LI by ImmunoRatio were associated with poor overall survival, in particular in the hormone receptor positive group.

Conclusions

The web-based automated image analysis program ImmunoRatio is an attractive alternative to manual counting to determine the Ki-67 LI in breast cancer.

Prognostic value of different cut-off levels of Ki-67 in breast cancer: a systematic review and meta-analysis of 64,196 patients

A proliferative marker, expressed as the percentage of cells in a cell cycle, has been developed and used as a discriminant of more aggressive malignant phenotypes in early breast cancer (BC). The marker is usually expressed by the immunohistochemical staining of the cell cycle antigen Ki-67. It has not, however, yet been definitely evaluated, due to methodological concerns, which specific Ki-67 cut-off provide the strongest prognostic information in resected BC. We conducted a meta-analysis to explore the prognostic value of different cut-off levels of Ki-67 in terms of overall survival (OS) and disease-free survival (DFS) in early BC. The databases of PubMed, the ISI Web of Science, EMBASE, SCOPUS, the Cochrane Central Register of Controlled Trials, and CINHAL were used to identify the relevant literature. Data from studies reporting a hazard ratio (HR) and a 95 % confidence interval (CI) calculated as a multivariate analysis were pooled in a meta-analysis, with metaregression used to test for trends in predefined subgroups. All the statistical tests were 2-sided. Forty-one studies encompassing 64,196 BC patients were included in the analysis. Overall, n = 25 studies were available for the OS analysis. The pooled HR for high versus low Ki-67 was 1.57 (95 % CI 1.33-1.87, P < 0.00001). Twenty-nine studies were available for the DFS analysis. The pooled HR for high versus low Ki-67 was 1.50 (95 % CI 1.34-1.69, P < 0.00001). When a cut-off of Ki-67 staining ≥ 25 % was used, the pooled HR for OS was 2.05 (95 % CI 1.66-2.53, P < 0.00001), which was significantly different to studies where the cut-offs chosen were <25 %. In ER+ tumors, the HR for high versus low Ki-67 was similar and significant (HR = 1.51, 95 % CI 1.25-1.81, P < 0.0001). We conclude that Ki-67 has an independent prognostic value in terms of OS in BC patients. The Ki-67 threshold with the greatest prognostic significance is as yet unknown, but a cut-off >25 % is associated with a greater risk of death compared with lower expression rates.