The Performance of Ki-67 Labeling Index in Different Specimen Categories of Invasive Ductal Carcinoma of the Breast Using 2 Scoring Methods

Systematically higher Ki67 scores on core biopsy samples compared to corresponding resection specimen in breast cancer: a multi-operator and multi-institutional study

Ki67 has potential clinical importance in breast cancer but has yet to see broad acceptance due to inter-laboratory variability. Here we tested an open source and calibrated automated digital image analysis (DIA) platform to: (i) investigate the comparability of Ki67 measurement across corresponding core biopsy and resection specimen cases, and (ii) assess section to section differences in Ki67 scoring. Two sets of 60 previously stained slides containing 30 core-cut biopsy and 30 corresponding resection specimens from 30 estrogen receptor-positive breast cancer patients were sent to 17 participating labs for automated assessment of average Ki67 expression. The blocks were centrally cut and immunohistochemically (IHC) stained for Ki67 (MIB-1 antibody). The QuPath platform was used to evaluate tumoral Ki67 expression. Calibration of the DIA method was performed as in published studies. A guideline for building an automated Ki67 scoring algorithm was sent to participating labs. Very high correlation and no systematic error (p = 0.08) was found between consecutive Ki67 IHC sections. Ki67 scores were higher for core biopsy slides compared to paired whole sections from resections (p ≤ 0.001; median difference: 5.31%). The systematic discrepancy between core biopsy and corresponding whole sections was likely due to pre-analytical factors (tissue handling, fixation). Therefore, Ki67 IHC should be tested on core biopsy samples to best reflect the biological status of the tumor.

Ki-67 and breast cancer prognosis: does it matter if Ki-67 level is examined using preoperative biopsy or postoperative specimen?

Purpose

This study aimed to identify the association between Ki-67 level and the prognosis of patients with breast cancer, regardless of the timing of Ki-67 testing (using preoperative biopsy vs. postoperative specimen).

Methods

A total of 4177 patients underwent surgery between January 2008 and December 2016. Immunohistochemical Ki-67 levels, using either preoperative (1673) or postoperative (2831) specimens, were divided into four groups using cutoff points of 10%, 15%, and 20%.

Results

Groups with higher-Ki-67 levels, in both the pre- and postoperative periods, showed significantly larger tumor size, higher grade, more frequent hormone receptor-negativity and human epidermal growth factor receptor 2 overexpression, and active adjuvant treatments than groups with lower-Ki-67 levels. High-Ki-67 levels were also significantly associated with poor survival, irrespective of the timing of specimen examination.

Conclusion

Despite the problems associated with Ki-67, Ki-67 level is an important independent prognostic factor, regardless of the timing of Ki-67 testing, i.e., preoperative or postoperative testing.

Correlation of prognostic and predictive indicators in breast cancer patients from the eastern province of Saudi Arabia

OBJECTIVES

To highlight and correlate demographic and histopathological features of breast cancer along with prognostic and predictive biomarkers, in Saudi patients from the Eastern Province and compare it to a cohort of non-Saudi patients.

METHODS

In a retrospective study between January 1998 and December 2017, data were collected from the medical records of breast cancer patients who were admitted at King Fahd University Hospital (KFHU), Dammam, Saudi Arabia. The information included demographic, histopathological, and immunohistochemical findings.

RESULTS

Out of 482 breast cancer patients, 60% (n=286) were Saudis, and 40% (n=196) were non-Saudis. Data showed a wide age distribution; however, most cases (80%) were seen in the third through fifth decades, with a median age at diagnosis of 51 ±12 years. Over years, breast cancer in Saudi patients was increasingly seen at a younger age (p=0.003). While tumors were increasingly detected at earlier stages (p=0.003); however, stage III & IV tumors (p=0.033) and human epidermal growth factor receptor-2 overexpressed tumors (p=0.035) were more frequently seen at a younger age. Interestingly, these associations were not significant in non-Saudi patients.

CONCLUSION

Although, the current findings might help future studies to identify variables that could lead to better management of breast cancer in this region; however, a wider investigation including other centers in the eastern province is needed.

Combined Use of Unguided FNA and CNB Increases the Diagnostic Accuracy for Palpable Breast Lesions

BACKGROUND

Obtaining nonsurgical precise diagnosis of a palpable breast lesion is of paramount importance. Both core needle biopsy (CNB) and fine needle aspiration (FNA) are validated techniques used for this purpose. In this study, we compared the accuracy of both methods and explored whether combining both tests adds significant diagnostic value, and for the first time, we tested the concordance of tumor grading in parallel biopsies with reference to surgical excision (SE).

METHODS

Patients underwent concurrent unguided FNA and CNB followed by SE were retrospectively recruited. Chi-square was used to compare the accuracy of malignancy detection, and tumor grade agreement was calculated using kappa (k) statistical test with reference to SE findings.

RESULTS

All patients were females (n: 170). The median age was 45 years. Excluding 18 cases which had inadequate FNA, accuracy of FNA and CNB was 86.2% and 79.6%; respectively. Accuracy was 94.1% when we considered both tests together for any positive result. For tumor grading, the agreement was 91.6% for CNB and 98.8% for FNA.

CONCLUSION

Diagnostic strength was comparable for both FNA and CNB, slightly more favorable for the former. Combination of both tests significantly minimized missing cases as false negative. When available, it is worthy to grade malignant FNA samples. Diagn. Cytopathol. 2016;44:578-581. © 2016 Wiley Periodicals, Inc.