Mean Ki-67 Values Research Articles

Abstract PS15-06: Results of the window-of-opportunity PIONEER trial evaluating addition of the progesterone receptor (PR) agonist megestrol to letrozole for early stage estrogen receptor (ER) positive breast cancer: exploiting ER-PR interaction

Abstract Background: Pre-clinical data suggest that combining anti-estrogen treatment with a progesterone receptor agonist leads to greater inhibition of tumor proliferation, due to molecular interactions between ER and PR [1]. A high dose of the PR agonist megestrol (160mg daily) is approved as monotherapy for the treatment of ER positive metastatic breast cancer. A lower dose of megestrol (20-40mg daily) can be an effective treatment for severe hot flashes associated with endocrine therapy [2] but whether this dose has anti-tumor activity is unknown. The PIONEER trial evaluated the potential anti-proliferative effect of low and high dose megestrol in combination with letrozole, relative to letrozole alone, using a short-term preoperative ‘window’ trial design assessing the direct effects of the trial treatment on tumor tissue before and after treatment. Methods: Eligible patients were post-menopausal women with histologically confirmed ER+ (Allred ≥ 3) HER2 negative breast cancer at least 10mm in size, with an ECOG performance status ≤ 2, planned for primary surgery or endocrine therapy. Enrolled patients were randomised 2:3:3 to Arm A: letrozole alone, Arm B: letrozole + lower-dose megestrol (40mg) or Arm C: letrozole + higher-dose megestrol (160mg). Treatment was given for 15 (13-19) days prior to surgery or end of treatment (EOT) core biopsy. The primary endpoint was change in tumor proliferation between baseline and EOT in Arm A vs (Arms B+C combined), measured by Ki67 immunohistochemistry (IHC). Secondary endpoints were comparison of Ki67 change in high versus low dose megestrol arms, absolute Ki67 at EOT, and change in tumor apoptosis (cleaved caspase 3 IHC), proliferation (Aurora Kinase A IHC), PR and androgen receptor expression. Exploratory analysis of ER chromatin binding (ChIP-Seq) was conducted on paired fresh-frozen samples from a subset of patients. Results: A total of 243 patients were randomised from July 2017 to October 2022 with recruitment paused for 3 months at onset of the COVID pandemic. 198 patients completed treatment and had evaluable tissue samples at baseline and EOT (Arm A: n = 51, Arm B: n = 74, Arm C: n = 73). Baseline mean Ki67 values were well balanced. Therapy was well tolerated and adverse events ≥ grade 3 were similarly rare across arms (A: 3.3%, B+C: 3.5%). The mean % reduction in Ki67 for each arm was: Arm A (letrozole): 71%, Arm B (letrozole + 40mg megestrol): 79%, Arm C (letrozole + 160mg megestrol): 80%. There was a statistically significantly greater reduction in Ki67 with megestrol combinations (B+C) versus letrozole alone (A) (P = 0.013). Analyses of secondary IHC endpoints and ER ChIP-Seq are ongoing and will be presented. Conclusion: Addition of the PR agonist megestrol enhanced the anti-proliferative effect of letrozole in this window-of opportunity trial. Megestrol combinations were well tolerated, and the anti-proliferative effect was observed in both low and high dose arms. These data support the potential use of low-dose megestrol as an inexpensive and well-tolerated means of improving aromatase inhibitor efficacy. Low dose megestrol can also ameliorate hot flashes and therefore might be a strategy to improve both treatment adherence and clinical outcomes for patients taking adjuvant endocrine therapy.

Effects of hormone receptor status on patient clinic and survival in HER2 positive breast cancer.

In the current study, the effect of hormone receptor (HR) status on clinical and survival in early-stage human epidermal growth factor receptor 2 (HER2)-positive breast cancer was investigated. Two hundred ninety-one patients with HER2- positive were examined in two categories as HR-positive and HR-negative. Of these, 197 (68%) were HR-positive and 94 (32%) were HR-negative with a mean follow-up period of 68±2.7months. The groups were found to be similar in terms of age, menopausal status, comorbidity, pathologic type, stage, T stage, N stage, lymphovascular invasion, presence and percentage of intraductal component, multicentricity/focality and extracapsular invasion. Family history (P=0.038), stage 2 tumor rate (P<0.001), and perineural invasion (P=0.005) were significantly higher in the HR-positive group. In the HR-negative group, mean Ki-67 value (P =0.014), stage 3 tumor rate (P<0.001), tumor necrosis (P=0.004) and strong (3+) HER2 staining on immunohistochemical staining (P=0.003) were higher. The incidence of relapse and metastasis, and the localization of metastasis were similar in both patient groups. The rate of locoregional relapse during the first 2years was higher in the HR-negative patients than in the HR-positive patients (P=0.023). Overall survival (OS) and disease-free survival (DFS) did not differ between the groups in univariate analysis. However, HR status was determined as an independent prognostic factor (HR: 2.11, 95% CI: 1.17-3.79; P=0.012) for OS was not found to be significant for DFS in multivariate analysis. Both clinicopathologic features and OS outcomes of HR-negative patients were worse than those of HR-positive patients.

Effect of Ki-67 proliferation index on survival in large cell neuroendocrine carcinoma of the lung.

Large cell neuroendocrine carcinoma of the lung is a rare type of lung cancer. There is a limited number of studies on clinical and histopathological characteristics that are effective in survival. The aim of this study was to investigate the relationship between histopathological and clinical characteristics, mainly Ki-67 proliferation index, and survival in patients diagnosed with large cell neuroendocrine carcinoma of the lung. The data of 38 patients followed up with the diagnosis of large cell neuroendocrine carcinoma of the lung were evaluated. The mean Ki-67 value was determined to be 65.8% (±20.8). The patients' clinical characteristics and survival times were compared according to the cut-off value determined for Ki-67 index. When median overall survival times were compared, it was seen that overall survival was numerically lower in patients aged 65 years and over, in tumors located on the right side, in cases who were in the metastatic stage at diagnosis, whose Ki-67 index was 65% and above, who did not receive chemotherapy, who did not undergo curative surgery, and in patients with chronic diseases (p>0.05). In the Kaplan-Meier analysis, the median overall survival was determined to be 22.2 months (95%CI 21.7-22.7) in the patients with Ki-67<65%, while it was found to be 20.3 months (95%CI 4.5-36.2) in the patients with Ki-67≥65% (p=0.351). Our study identified subgroups with decreased survival in large cell neuroendocrine carcinoma of lung patients. Studies including a larger number of patients are needed to identify the prognostic importance of these clinical and histopathological characteristics.

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

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

Inflammatory myofibroblastic tumor of the bladder: Computed tomographic features.

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with intermediate biologic potential, in which lack of understanding often poses difficulties in preoperative diagnosis and treatment. The aim of the present study was to characterize the computed tomography (CT) features of the bladder IMT. The CT images of nine pathologically confirmed bladder IMT were retrospectively reviewed. All patients underwent both unenhanced CT and contrast-enhanced CT. The diameter, location, contour, growth pattern, margin, boundary, density and enhancement pattern of the lesions were assessed. The mean Ki67 value of an irregular blood clot was 18% and that of no blood clot was 12%. A total of eight (89%) patients had one tumor and 1 (11%) patient had multiple tumors. An endophytic growth pattern was observed in 4 (44%) patients, an exophytic growth pattern in 2 (22%) patients, and a mixed growth pattern in 3 (33%) patients. The tumor manifests morphologically as either polypoid (n=5), or cauliflower-like (n=1) soft-tissue mass with a wide base in the cavity, or a limited thick-walled (n=3). The tumor margins were smooth (n=8) or lobulated (n=1), and the tumor boundaries were either clear (n=7) or ill-defined (n=2). The lesions showed either ring-shaped (n=3) or heterogeneous (n=6). The polypoid and cauliflower-like soft-tissue mass showed a symmetrical change in the center of the lesion after enhancement. The bladder IMT is mostly a single polypoid nodule in the superior wall, mostly endophytic growth, with ring-haped enhancement and symmetrical change after enhancement as its characteristic manifestations.

Triple-negative breast cancer - a retrospective audit of 151 cases seen at the Charlotte Maxeke Johannesburg Academic Hospital Breast Unit

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive, rapidly lethal subgroup of breast cancer which disproportionately affects women of African descent. Lacking hormone receptor expression and human epidermal growth factor receptor 2 (HER2) overexpression, it is difficult to treat. Despite an initial good response to chemotherapy, relapse is common and survival short. The aim of this study of treatment-naive women with TNBC was examination of clinicopathological characteristics and any association of these with patient demographics. METHODS: Demographic data was captured together with the clinical, pathological and histological features of the cancers. Statistical analysis was performed. RESULTS: Of the 960 patients entered in the database of the Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) Breast Unit (BU) over a 3-year period, 151 (15.7%) had TNBC. All patients were female aged 25 to 98 years, and 60.3% were postmenopausal (mean age 64 years). The majority (80.2%) self-identified as black African. Most patients had clinical stage 3 disease, and 17.2% had distant metastases. One hundred women were HIV negative, 35 positive and 20 untested. Tumour biology revealed high-grade morphology in 70% of cases with a mean Ki-67 value of 60%. Forty patients died within 18 months of entry in the database. CONCLUSION: In this series, most patients with TNBC were older, postmenopausal women. This patient cohort may represent a non-basal subtype of TNBC but gene expression profiling was not available. Tumours were locally advanced, rapidly proliferative but not associated with HIV status. The short survival times emphasise the importance of neoadjuvant chemotherapy as soon as the diagnosis of TNBC is made.

Long-term surgical outcomes of gastric neuroendocrine carcinoma and mixed neuroendocrine-non-neuroendocrine neoplasms

BackgroundNeuroendocrine carcinoma (NEC) and mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) are extremely rare subtypes of gastric cancer. MiNEN is a mix of carcinomatous components and neuroendocrine neoplasm in the same lesion. NEC and MiNEN have a poor prognosis, are difficult to diagnose, and have no established treatment. Herein, we assessed the clinicopathological characteristics and long-term surgical outcomes of gastric NEC and MiNEN patients in our hospital.MethodsWe retrospectively assessed 1538 patients pathologically diagnosed with gastric cancer and who underwent curative surgical resection at our institution between January 1999 and October 2021. Of these patients, 25 (1.6%) were pathologically diagnosed with neuroendocrine neoplasms. From these 25 patients, we retrospectively analyzed the clinicopathological characteristics and surgical outcomes of 13 (0.8%) patients pathologically diagnosed with NEC or MiNEN.ResultsThe NEC and MiNEN patients consisted of 11 men and 2 women [mean age, 74 (62–84) years]. The preoperative histological diagnoses were NEC (n = 4) and adenocarcinoma (n = 9). The final pathological diagnoses were large cell neuroendocrine carcinoma (LCNEC; n = 7) and MiNEN (n = 6). Total gastrectomy was the most common surgical procedure (9/13, 69.2%), followed by distal gastrectomy (3/13, 23.1%) and proximal gastrectomy (1/13, 7.7%). Immunohistochemical staining showed 8 CD56-positive patients. All 13 patients were positive for chromogranin A and synaptophysin. The mean Ki-67 value was 64.8 (0–95)%, and the mean mitotic score was 107.9 (0–400). Nine patients survived without recurrence postresection. The median postresection overall survival time was 68.7 (8.0–129) months. The 5-year survival rate was 0.75 ([95% CI] 0.408–0.912).ConclusionThe surgical treatment outcomes of NEC and MiNEN patients were relatively favorable. Although evidence concerning the effectiveness of surgery alone is meager, radical resection as part of multidisciplinary treatment including chemotherapy can potentially improve prognosis.

Comparative Analysis of Ki-67 in Different Scoring Patterns and its Association with other Prognostic Markers of Breast Carcinoma

Introduction: Immunohistochemical evaluation of Ki-67 is widely used for estimation of tumour proliferation in breast cancer. Till date, no specific method or a cut-off point for Ki-67 exists. Aim: To perform a comparative analysis between different scoring patterns and mean Ki-67 value and association of mean Ki-67 with other prognostic markers like tumour size, lymph node status, tumour stage and grade and different molecular subtypes of breast cancer. Materials and Methods: A cross-sectional study was conducted at Dr. D.Y Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India, between August 2019 to August 2021. Total of 50 new diagnosed cases of breast cancer were studied for the histologic type, grade and stage of the tumour. Immunohistochemistry for Oestrogen Receptor (ER), Progesterone Receptor (PR), Human Epidermal Growth Factor Receptor 2 (HER2) and Ki-67 was performed. Association of Ki-67 with other prognostic markers like tumour size, lymph node status, tumour stage and grade and different molecular subtypes of breast cancer was evaluated by expressing Ki-67 as a continuous variable (mean±SD) and also by dividing Ki-67 into different scoring patterns (I: ≤14%, &gt;14%, II: ≤15%, 16- 30%, &gt;30% and III: &lt;20%, 20-50%, ≥50%). Statistical tests like Kruskal-Wallis test (mean Ki-67 with tumour size, tumour grade and molecular subtypes), Mann-Whitney Rank Sum Test (mean Ki-67 with lymph node status) and Analysis of variance (ANOVA) (mean Ki-67 with staging) respectively. Results: Out of 50 patients, 40 (80%) were older than 50-yearold. Twenty six (52%) cases affected the left breast. A total of 49 (98%) were diagnosed as Invasive Ductal Carcinoma (IDC). Among them 26 (52%) cases were of grade III and 25 (50%) cases were of Luminal A. Mean Ki-67 and molecular subtypes of breast cancer had statistically significant association (p= 0.002). No association was found between mean Ki-67 and tumour size (p=0.608), lymph node status (p=0.506) stage (p=0.979) and grade (p=0.095) of the tumour. Although scoring pattern I and III had no remarkable findings. Notably, scoring pattern II showed higher tumour sizes, lymph node positivity, higher stage and grade and basal-like tumours demonstrated a higher Ki-67 index. Conclusion: Evaluation of Ki-67 as a continuous variable yielded significant association with other prognostic markers of breast cancer. There was no single “best” scoring pattern identified. A direct association of Ki-67 was found with molecular subtypes of breast cancer.

Influence of Human Telomerase Reverse Transcriptase Mutation on the Aggressiveness and Recurrence in Meningiomas.

Background: Over 200 human telomerase reverse transcriptase (hTERT) polymorphism combinations have been implicated in the development of cancer. This study aimed to evaluate hTERT mutations in meningioma tissue and its association with meningioma.Material and Methods: A total of 90 patients who underwent surgery between 2006 and 2015 and were histopathologically diagnosed with meningioma (WHO 2016) were included.Results: Among the 90 participants included herein, 50 (55.5%) and 40 (44.5%) were female and male, respectively, with an average age of 56.2 ± 14 years. Mean Ki-67 values were 10.56% (SD 12.41, range 0-60), while the mean follow-up duration was 39.1 months (SD 26.3). Low- and high-grade patients had a mean Ki-67 score of 4.31% (SD 3.58, range 0-16) and 19.92% (SD 14.91, range 2-60) (p = 0.0001). Our results showed a moderate positive correlation between Ki-67 score and the presence of hTERT mutation (Pearson correlation test, r = 0.5161; p = 0.0001). Patients with an hTERT mutation > 30% had significantly higher risk for reoperation than those with lower levels of mutation (p = 0.016, chi square test). None of the patients requiring reoperation had an hTERT mutation < 10%. Moreover, high-grade patients had a 7.2 times higher risk of reoperation than those with an hTERT mutation > 30%.Conclusion: The presence of hTERT mutation, in addition to high Ki-67, indicated a more aggressive meningioma disease course and potentially increased risk of recurrence.

Is vimentin a potential prognostic factor for patients with triple-negative breast cancer?

To evaluate the prognostic potential of vimentin, p53, EGFR, CK5/6, CK 14, and CK 17 in patients with triple-negative breast cancer (TNBC). Tumor specimens of 60 patients with histologically confirmed TNBC were retrospectively analyzed. Formalin-fixed paraffin-embedded blocks of the tumor tissue were used to prepare tissue microarrays (TMAs). After immune-histochemical staining, protein expression of vimentin, p53, EGFR, CK5/6, CK 14, and CK 17 was determined and the immunoreactive score (IRS) was calculated. The protein expression was correlated to overall (OS) and disease-free survival (DFS). Ninety percent of patients suffered from an invasive ductal carcinoma T1 or T2, 66.7% were N0, and 70% had a G3 tumor with Ki67 of > 14%. Vimentin expression was found in 28/60 patients (46.7%), p53 expression in 30/60 patients (50%), and EGFR expression in 3/60 patients (5%). CK5/6, CK14, and CK17 expression was found in 60.0%, 63.3%, and 66.7%, respectively. Vimentin expression vs no expression was associated with significantly higher mean Ki67 values (52.5% vs. 31.1%; p = 0.0013) and significantly higher p53 expression (67.9% vs. 34.4%; p = 0.0097). No significant association between vimentin expression and OS (p = 0.7710) or DFS (p = 0.5558) was found during a mean follow-up of 92months. None of the six proteins proved to be suitable prognostic factors for OS and DSF in patients with TNBC.

Study of Ki-67 index in the molecular subtypes of breast cancer: Inter-observer variability and automated scoring.

Ki-67 index is an important prognostic marker in breast cancer and is also used to differentiate luminal A subtype from luminal B. Inter-observer variations in determining the index and the cut-off value to be considered in distinguishing the two subtypes remain problems in clinical practice. MIB-1 immunohistochemistry was done on 200 cases of breast cancer with 50 cases in each molecular subtype. The Ki-67 scoring was done manually by two observers and automated method (using the software ImmunoRatio). The mean value of Ki-67 was calculated in each molecular group and in the entire estrogen receptor and progesterone receptor (ER/PR) positive group. The inter-observer variability between the two observers and the automated method was also assessed. The mean and median values of Ki-67 of all the 200 cases obtained by manual scoring was 31.13% and 29.65% by observer 1, 28.48% and 27.90% by observer 2, and 38.27% and 35.45% by the automated method. The mean Ki-67 value obtained by manual scoring, in luminal A, luminal B, HER2 enriched and triple negative was 21.07%, 37.19%, 33.72% and 27.27%, respectively. There was significant correlation between the two observers and with the automated scoring.. The mean value of the Ki-67 index in the ER/PR positive group was 29.1%. The inter-observer correlation and the correlation with the automated scoring system of the Ki-67 index was good. 29.1% was the mean Ki-67 index in the ER/PR positive group and this value was within the acceptable range as per St Galen's recommendation.

Ki-67 assessment in early breast cancer: SAKK28/12 validation study on the IBCSG VIII and IBCSG IX cohort

The assessment of Ki-67 in early-stage breast cancer has become an important diagnostic tool in planning adjuvant therapy, particularly for the administration of additional chemotherapy to hormone-responsive patients. An accurate determination of the Ki-67 index is of the utmost importance; however, the reproducibility is currently unsatisfactory. In this study, we addressed the predictive/prognostic value of Ki-67 index assessed by using the most reproducible methods, which were identified in the pilot phase. Paraffin blocks obtained from patients with moderately differentiated, estrogen receptor (ER)-positive early-stage breast cancer in Switzerland, who were originally randomized to the treatment arms with and without chemotherapy in the IBCSG VIII-IX trials, were retrieved. Of these 344 randomized patients, we identified 158 patients (82 treated with and 76 treated without chemotherapy) for whom sufficient tumour tissue was available. The presence of Ki-67 was assessed visually by counting 2000 cells at the periphery (A) and estimating the number of positive cells in five different peripheral regions (C), which was determined to be the most reproducible method identified the pilot phase. The prognostic and predictive value was assessed by calculating the breast cancer-free interval (BCFI) and overall survival (OS) rate. Ki-67 was considered a numerical and categorical variable when different cut-off values were used (10%, 14%, 20% and 30%). An mRNA-based subtyping by using the MammaTyper kit with the application of a 20% Ki-67 immunohistochemistry (IHC) cut-off equivalent was also performed. 158 of 344 randomized patients could be included in the Ki-67 analysis. The mean Ki-67 values obtained by using the two methods differed (A: 21.32% and C: 16.07%). Ki-67 assessed by using method A with a cut-off of 10% was a predictive marker for OS, as the hazard ratio (>10% vs. <=10%) in patients with chemotherapy was 0.48 with a 95% confidence interval of [0.19–1.19]. Further, the HR of patients treated without chemotherapy was 3.72 with a 95% confidence interval of [1.16–11.96] (pinteraction=0.007). Higher Ki-67 index was not associated with outcome and using the 10% Ki-67 cut-off there was an opposite association for patients with and without chemotherapy. Ki-67 assessments with IHC significantly correlated with MammaTyper results (p=0.002). The exact counting method (A) performed via a light-microscope revealed the predictive value of Ki-67 assessment with a 10% cut-off value. Further analyses employing image analyses and/or mRNA-based-assessments in larger populations are warranted.

Prognostic value of Ki-67 index in adult medulloblastoma after accounting for molecular subgroup: a retrospective clinical and molecular analysis

Medulloblastoma (MB) is a rare primary brain tumor in adults. We previously evaluated that combining both clinical and molecular classification could improve current risk stratification for adult MB. In this study, we aimed to identify the prognostic value of Ki-67 index in adult MB. Ki-67 index of 51 primary adult MBs was reassessed using a computer-based image analysis (Image-Pro Plus). All patients were followed up ranging from 12months up to 15years. Gene expression profiling and immunochemistry were used to establish the molecular subgroups in adult MB. Combined risk stratification models were designed based on clinical characteristics, molecular classification and Ki-67 index, and identified by multivariable Cox proportional hazards analysis. In our cohort, the mean Ki-67 value was 30.0 ± 11.3% (range 6.56-63.55%). The average Ki-67 value was significantly higher in LC/AMB than in CMB and DNMB (P = .001). Among three molecular subgroups, Group 4-tumors had the highest average Ki-67 value compared with WNT- and SHH-tumors (P = .004). Patients with Ki-67 index large than 30% displayed poorer overall survival(OS) and progression free survival(PFS) than those with Ki-67 less than 30% (OS: P = .001; PFS: P = .006). Ki-67 index (i.e. > 30%, < 30%) was identified as an independent significant prognostic factor (OS: P = .017; PFS: P = .024) by using multivariate Cox proportional hazards model. In conclusion, Ki-67 index can be considered as a valuable independent prognostic biomarker for adult patients with MB.

Distinctive pathological and clinical features of lung carcinoids with high proliferation index

Typical (TCs) and atypical carcinoids (ACs) are defined based on morphological criteria, and no grading system is currently accepted to further stratify these entities. The 2015 WHO classification restricts the Ki-67 role to biopsy or cytology samples, rather than for prognostic prediction. We aimed to investigate whether values and patterns of Ki-67 alone would allow for a clinically meaningful stratification of lung carcinoids, regardless of histological typing. Ki-67 proliferation index and pattern (homogeneous versus heterogeneous expression) were assessed in a cohort of 171 TCs and 68 ACs. Cases were subdivided into three Ki-67 ranges (<4/4–9/≥10%). Correlations with clinicopathological data, univariate and multivariate survival analyses were performed. The majority of cases (61.5%) belonged to the <4% Ki-67 range; 25.1 and 13.4% had a proliferation index of 4–9% and ≥10%, respectively. The <4% Ki-67 subgroup was significantly enriched for TCs (83%, p < 0.0001); ACs were more frequent in the subgroup showing Ki-67 ≥ 10% (75%, p < 0.0001). A heterogeneous Ki-67 pattern was preferentially seen in carcinoids with a Ki-67 ≥10% (38%, p < 0.02). Mean Ki-67 values ≥4 and ≥10% identified categories of poor prognosis both in terms of disease-free and overall survival (p = 0.003 and <0.0001). At multivariate analysis, the two thresholds did not retain statistical significance; however, a Ki-67 ≥ 10% identified a subgroup of dismal prognosis even within ACs (p = 0.03) at univariate analysis. Here, we describe a subgroup of lung carcinoids showing brisk proliferation activity within the necrosis and/or mitotic count-based categories. These patients were associated with specific clinicopathological characteristics, to some extent regardless of histological subtyping.

Distribution of Ki-67 values within HER2 & ER/PgR expression variants of ductal breast cancers as a potential link between IHC features and breast cancer biology

BackgroundUnexpected differences in Ki-67 values among HER2 & ER/PgR defined subgroups were found. This study aims to detect possible subdivisions beyond the conventional breast cancer types.MethodsOne thousand one hundred eighty consecutive patients with invasive ductal breast carcinoma were included and distributed in 16 subgroups (four HER2 phenotypes (0+, 1+, 2+ and 3+) times four ER/PgR phenotypes). Complex distributions of Ki-67 values were tested by expectation maximization (EM) clustering.ResultsPooled Ki67 values of all patients showed the presence of three EM clusters (defined as LMA-low mitotic activity, IMA-intermediate mitotic activity and HMA-high mitotic activity) with expected mean Ki-67 values of 1.17%, 40.45% and 77.79%, respectively. Only ER-PgR- tumors significantly dispersed in three clusters (29.75% tumors in LMA, 46.95% in IMA and 23.30% in the HMA cluster), while almost no detected HMA tumors were of ER + PgR+ or ER + PgR- phenotypes.Among 799 ER + PgR+ patients distribution in clusters was HER2 dependent (p = 0.000243), due to increased number of IMA HER2 3+ tumors on the expense of LMA HER2 3+ tumors (52 IMA out of 162 HER2 3+ patients versus113 IMA out of 637 HER2 < 3+ patients). This was not found among ER + PgR- patients (p = 0.186968).Among ER-PgR- patients, HER2 overexpression also increased number of IMA tumor, but by reducing the number of HMA tumors (p < 0.000001). Here, difference between HER2 absent (0+) and HER2 3+ patients was evident (10 HMA out of 125 HER2 3+ patients versus 42 HMA out of 103 HER2 0+ patients).ConclusionsResults suggest that distributions of breast cancers in three clusters of mitotic activity depend on different mechanisms for ER + PgR+ and ER negative tumors. Although HER2 overexpression increases number of IMA tumors in both settings, in the former it is done by reducing number of LMA tumors, while in the latter it reduces the number of HMA tumors. Mitotic activity of ER + PgR- tumors seems unrelated to the HER2 status, possibly as an indicator that ER dysfunctionality in cancers that lack PgR expression. Among ER negative tumors, the absence of HER2 (0+) might be as important as the HER2 overexpression.

Changes in the biologic markers between primary tumor and ipsilateral breast tumor recurrence after breast conserving surgery: Discordance and prognosis.

1116 Background: Changes in biological markers due to recurrence are clinically experienced in breast cancer. However, the clinical significance is still uncertain, especially after breast conserving surgery. The changes in biological markers between primary tumor and ipsilateral breast tumor recurrence (IBTR) and their correlations with prognosis were investigated, retrospectively. Methods: A total of 117 consecutive patients with IBTR without distant metastases were enrolled in this study. All patients were examined for ER, PgR, HER2 and Ki-67 in both the primary and recurrent tumors. The cases were categorized into 3 groups: patients with Ki-67 values &lt;20%, &lt;50% and ≥50%, and divided into 2 groups according to the IBTR site, same quadrant(SQ)and different quadrant(DQ) from the initial sites. The distant disease-free survival (DDFS) was calculated using the Kaplan-Meier method and evaluated by the log-rank test and multivariate analyses using Cox proportional hazards model. The median follow-up period was 4.8 years after IBTR. Results: The PgR positive rate from the primary tumor to IBTR decreased from 57% to 39% and the Ki-67 values increased significantly from a mean of 17% to 23%. The concordance rate of the subtype was 62%. In the SQ group, the PgR positive rate significantly decreased and the mean Ki-67 values significantly increased, whereas there was no significant difference in the DQ group. In terms of changes by category due to relapse, the discordance rate in Ki-67 was high in the SQ group, and HER2 was high in the DQ group. Regarding DDFS by a change in the categorization, the cases with discordance in Ki-67 values had significantly lower DDFS in the SQ group(5-year DDFS: 75% vs 52%, p=0.04). However, a clear difference was not found in the DQ group. Conclusions: The PgR positive rate decreased while the mean Ki-67 values increased due to IBTR in the SQ group. The categorical discordance in the Ki-67 values was significantly associated with lower DDFS, especially in the SQ group. These findings suggest that the recurrent site and change in the biological markers were clinical significant in the evaluation of the characteristics and treatment in cases with IBTR.

Value of Ki-67 in prediction of response to neoadjuvant chemotherapy in breast cancer.

e12025 Background: The expression of the human Ki-67 protein has been described as being associated with cellular proliferative activity. The objective of this study is to assess the potential value of Ki-67 for the prediction of therapeutic response after neoadjuvant chemotherapy in breast cancer. Methods: Sixty-eight patients who underwent anthracyclin based neoadjuvant chemotherapy between 2007 and 2012 were included for this study. The chemotherapy response was evaluated by comparing the pre- and post-neoadjuvant chemotherapy tumor size on radiologic imaging study with the tumor size at pathologic specimens according to RECIST (response evaluation criteria in solid tumors) version 1.1. We analyzed immunohistochemical(ER, PR, HER2, Ki-67, p53) profiles from both pre-neoadjuvant core biopsy and postoperative specimens to find their correlations with chemotherapy response. Results: Ten patients(14.7%) achieved pathologic complete response(pCR), 38 patients(55.9%) had pathologic partial response(pPR) and 20 patients(29.4%) had pathologic stable disease(pSD). The mean Ki-67 value of tumors with pCR was 61.0%, the Ki-67 value of tumors with pPR was 35.9%, and the Ki-67 value of tumors with pSD was 21.0%(p = 0.013). The analysis of Ki-67 values of the patients also showed that 25% of Ki-67 level is a reasonable cut-off value for defining higher Ki-67 level. In subgroup analysis, the higher Ki-67 level was significant factor of the response to neoadjuvant chemotherapy, especially in ER negative patients(p = 0.009) and HER2 negative patients(p = 0.009). In addition, the analaysis of response group showed that ER negative(p = 0.027), HER2 positive(p = 0.048), and higher Ki-67 level(p = 0.002) were predictive indicators of complete response. Conclusions: The higher Ki-67 level of breast cancer tissue may effectively indicate the higher response rate to chemotherapy and also the higher complete response rate. The results of our study suggest that the Ki-67 value before neoadjuvant chemotherapy is a predictive factor for the response to neoadjuvant chemotherapy. Moreover, the Ki-67 is a predictive factor of the pathologic complete response especially in patients with ER negative or HER2 positive.

Abstract S4-6: An international Ki67 reproducibility study

Abstract Introduction: In breast cancer, immunohistochemical assessment of the cell proliferation marker Ki67 is of interest for potential use in clinical management (e.g. prognosis, prediction of treatment response, monitoring the effect of neoadjuvant therapy). However, lack of consistency across labs has limited the value of Ki67. A working group was assembled to devise a strategy to harmonize Ki67 analysis and scoring and to identify procedures to improve concordance (Dowsett et al. JNCI,'11). As a result, we have conducted an international Ki67 reproducibility study. Methods: Step 1: 100 breast cancer cases arranged into 1 mm core tissue microarrays (TMAs) were centrally stained using MIB-1 antibody. Eight labs scored Ki67 as the percentage of positively stained invasive tumor cells using their own local method. Six labs repeated scoring of 50 cases on the same TMA 3 times. Ki67 data were log2-transformed to approximate a normal distribution. Pairwise intra-lab and inter-lab concordance was displayed using Bland-Altman plots. Sources of variation (e.g. patient and lab) were analyzed using two-way crossed random effects models with quantification of reproducibility via intraclass correlation coefficient (ICC; range of 0–1, 1 = highest agreement). Step 2: A web-based scoring calibration interface was created to mitigate systematic differences in Ki67 interpretation observed in Step 1. Digital images of TMA cores from 9 “training” and 9 “test” cases representing a range of Ki67 values were assembled onto the web-based interface. An initial set of observers yielding consistent scores using a standardized scoring method served as reference labs. Detailed instructions for the standardized method were provided to 8 other labs, who were asked to score the cases and learn from discrepancies observed via the web tool. Statistical criteria for passing were pre-specified. Results: In Step 1, intra-lab reproducibility was high (ICC = 0.94). Inter-lab reproducibility was only moderate (ICC = 0.71). Absolute mean Ki67 values across the series ranged from 7% to 24%. Contributing to inter-lab discordance were tumor region selection, formal counting of nuclei versus visual estimation, and subjective assessment of staining positivity. Labs using formal counting methods gave more consistent results than those using visual estimation. The calibration exercise (Step 2) helped to improve consistency: all 8 labs passed the training exercise, 4 at first attempt and 4 after 1–2 rounds of retraining. When the same 8 labs scored the 9 test calibration cases, 3 passed on first attempt. Although overall concordance improved, discrepancies for cases with low Ki67 were largely responsible for the failure of the remaining 5 labs to pass the testing. Conclusions: Absolute values and cutpoints for Ki67, and associated clinical decisions, cannot be transferred between laboratories without careful standardization of scoring methodology. Our calibration training tool offers an initial process to improve inter-lab concordance, but further studies are required to establish what concordance can be achieved in practice. A large subsequent study will assess whether a pre-specified target of success (ICC = 0.9) can be achieved on glass slides after training with the web-based calibration tools developed as part of this study Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S4-6.

Ki67, chemotherapy response, and prognosis in breast cancer patients receiving neoadjuvant treatment

BackgroundThe pathological complete response (pCR) after neoadjuvant chemotherapy is a surrogate marker for a favorable prognosis in breast cancer patients. Factors capable of predicting a pCR, such as the proliferation marker Ki67, may therefore help improve our understanding of the drug response and its effect on the prognosis. This study investigated the predictive and prognostic value of Ki67 in patients with invasive breast cancer receiving neoadjuvant treatment for breast cancer.MethodsKi67 was stained routinely from core biopsies in 552 patients directly after the fixation and embedding process. HER2/neu, estrogen and progesterone receptors, and grading were also assessed before treatment. These data were used to construct univariate and multivariate models for predicting pCR and prognosis. The tumors were also classified by molecular phenotype to identify subgroups in which predicting pCR and prognosis with Ki67 might be feasible.ResultsUsing a cut-off value of > 13% positively stained cancer cells, Ki67 was found to be an independent predictor for pCR (OR 3.5; 95% CI, 1.4, 10.1) and for overall survival (HR 8.1; 95% CI, 3.3 to 20.4) and distant disease-free survival (HR 3.2; 95% CI, 1.8 to 5.9). The mean Ki67 value was 50.6 ± 23.4% in patients with pCR. Patients without a pCR had an average of 26.7 ± 22.9% positively stained cancer cells.ConclusionsKi67 has predictive and prognostic value and is a feasible marker for clinical practice. It independently improved the prediction of treatment response and prognosis in a group of breast cancer patients receiving neoadjuvant treatment. As mean Ki67 values in patients with a pCR were very high, cut-off values in a high range above which the prognosis may be better than in patients with lower Ki67 values may be hypothesized. Larger studies will be needed in order to investigate these findings further.

Ki-67 from Clinically and Histologically “Normal” Distant Mucosa as Prognostic Marker in Early-Stage (T1-T2N0) Oral Squamous Cell Carcinoma: A Prospective Study

The aggressive behavior and long-term prognosis of oral squamous cell carcinoma (OSCC) have recently been related to the mucosa surrounding the primary mass, consisting of genetically altered cells that might be responsible for cancer progression. Early-stage T1-T2N0 OSCCs have been associated with a good prognosis; however, a certain percentage of them can be complicated by locoregional metastases. The purpose of our study was to determine whether an abnormal proliferative status can be found in clinically and histologically "normal" mucosa situated in areas distant from the primary tumor. We also sought to determine whether this is associated with a poor prognosis in terms of local recurrence or lymph node metastasis. The prospective study included 42 consecutive patients with T1N0M0 (n = 19) and T2N0M0 (n = 23) OSCC. Disease-free survival endpoints were defined as the duration between surgical resection and the diagnosis of recurrence, lymph node metastasis, or last follow-up visit. Proliferative status in distant areas (opposite cheek) was evaluated by Ki-67 expression. The mean Ki-67 value (17.6% ± 8.2%) in the distant mucosa was significantly greater (F = 13.87; P < .01) than that found in the controls (9.8 ± 3.1). "Abnormally high" Ki-67 values were detected in 13 patients with OSCC (30%). Four patients developed locoregional recurrence during follow-up. Kaplan-Meier analysis showed that Ki-67 in the distant mucosa was a significant independent prognostic factor for disease-free survival. A certain percentage of patients surgically treated for early T1-T2 OSCC will have an abnormal proliferative status in areas very distant from the primary tumor that seems to be related to a poor prognosis.