Inter-laboratory comparison of Ki-67 proliferating index detected by visual assessment and automated digital image analysis.

BACKGROUND: Proliferation rate is a major determinant of the biologic behavior of the tumor and provides information that can be used to guide treatment decisions. METHODS: This ring study included 27 pathologists from 14 Institutions, in order to assess inter-observer concordance between pathologists in Croatia. We analyzed Ki-67 proliferative index on ten randomly selected breast cancer samples comparing consistency between visual assessment using light microscopy compared to digital image analyses results from one central laboratory as a referral value. RESULTS: When we analyzed Ki-67 as numeric value high concordance rate was found between Ki-67 score visually assessed in all participating Institutions compared to referral value assessed by digital image analysis (ICC 0.76, 95% CI 0.58-0.91), and Krippendorff's alpha was 0.79 (95% CI 0.58-1.00). Concordance was better in slides with higher Ki-67 values. When we categorized Ki-67 values according to generally accepted 20% cut-off value we noticed the lower concordance rate among participants in our study. CONCLUSION: Proliferation remains one of the most important parameters for tumor characterization helpful in making clinical decisions, but it should be used with great caution. Standardization of the Ki-67 assessment is essential and proliferating index should be expressed as exact numeric value. For patients with proliferative index near the cut-off value, other factors must be considered in making clinical decisions.

[CLINICAL RECOMMENDATIONS FOR DIAGNOSIS, TREATMENT AND MONITORING OF PATIENTS WITH ESOPHAGEAL AND ESOPHAGOGASTRIC JUNCTION CANCERS].

Esophageal and esophagogastric junction cancers comprise histologically and biologically different malignant tumors in which the progress in the understanding of the disease has not been followed by the improvement in the survival. Diagnosis is set by tumor biopsy during endoscopy. Multimodal approaches containing surgery, radiotherapy and chemotherapy are frequently applied in the treatment of locoregionally advanced disease. However, the optimal sequence of the treatment options is still the issue of numerous clinical trials and meta-analyzes. Metastatic disease is treated with palliative chemotherapy and best supportive care. Treatment decisions should be individualized according to patients' characteristics and made after multidisciplinary team discussion. The following text presents the clinical guidelines in order to standardize the diagnostic procedures, treatment and monitoring of patients with esophageal and esophagogastric junction cancers in the Republic of Croatia.

INTERLABORATORY CONCORDANCE IN HER-2 POSITIVE BREAST CANCER.

Accurate assessment of HER-2 status is essential for identifying patients who will benefit from HER-2 targeted therapy. The aim of the present study was to show results on the concordance between local and central laboratory testing results in HER-2 positive breast cancer patients. In cases with discordant findings, the immunohistochemical (IHC) and/or in situ hybridization (FISH/SISH) analysis was performed in central laboratories. A total of 104 out of 143 (72.72%) breast carcinoma cases were HER-2 positive (score 3+), while nearly 14% of tumors (20/43) showed weak (score 2+) and 12% (19/143) negative IHC staining (score 0 and 1+). After repeated IHC and ISH, 88% (126/143) were classified as HER-2 positive and 12% (17/143) as HER-2 negative cases. The results obtained are in agreement with many studies that confirmed similar discordance in HER-2 testing by IHC and/or FISH between local and central laboratory. Thus, our findings as well as those from other studies support the importance of regular quality assessment of the staining procedures performed and consistency of interpretation of HER-2 test results.

Expression of genes responsible for the repair of mispaired bases of the DNA (MLH1) in invasive ductal breast carcinoma.

Breast cancer is a heterogeneous group of diseases determined and distinguished by cellular type, gene expression and clinical signs and symptoms. Identification of histological and biological markers is of great value in predicting the progression of tumor growth and anticipating the expected response to various treatment options. Due to a high degree of cell proliferation in breast tumors and high genetic instability of these tumors, as a consequence of defective DNA repair mechanisms, chemotherapy as a treatment option often renders very successful results. During our scientific research we wanted to determine the involvement of the genetic polymorphisms of DNA mismatch repair system (MLH1 gene) and the subsequent development of breast carcinoma. This study included 108 patients who were surgically treated for invasive breast cancer at the Department of Plastic, Reconstructive and Aesthetic Surgery, University Hospital "Dubrava". The expression of the MLH1 gene was determined by immunohistochemical methods. The results showed that 82.9% of tumor cells expressed the MLH1 gene. Analysis of survival rate for patients with invasive ductal breast cancer showed a statistically significant (p = 0.043) correlation with the expression of MLH1 genes. The overall five year survival rate of our patients was 78.7%. These results indicate that there is a possible involvement of MLH1 gene in the progression and development of breast cancer.

Role of Ki-67 as a prognostic factor in gastrointestinal stromal tumors.

AIM: To investigate primarily the prognostic value of Ki-67, as well as other parameters, in gastrointestinal stromal tumors (GISTs). METHODS: Ki-67, c-KIT, platelet-derived growth factor receptor-alpha (PDGFRα), smooth muscle actin (SMA), CD34, S100 were stained for immunohistochemistry which was performed on formalin-fixed, paraffin-embeded sections on representative block from each case. Proliferation index counted by Ki-67 antibody was calculated as a number of positive nuclear reaction over 100 cells. Immunoreactivity for c-KIT and PDGFRα was evaluated semiquantitatively (weak, intermediate, strong) and for c-KIT type of reactivity was analyzed (cytoplasmic, membrane and "dot-like" staining). Immunoreactivity for SMA, CD34 and S100 were was evaluated as positive or negative antigen expression. Pathologic parameters investigated in this study included tumor size, cell type (pure spindle, pured epitheloid mixed spindle and epitheloid), mitotic count, hemorrhage, necrosis, mucosal ulceration. Clinical data included age, gender, primary tumor location and spread of disease. χ² test and Student's t-test were used for comparisons of baseline characteristics. The Cox's proportional hazard model was used for univariable and multivariable analyses. Survival rates were calculated by Kaplan-Meier method and statistical significance was determined by the log-rank test. RESULTS: According to the stage of disease, there were 36 patients with localized disease, 29 patients with initially localized disease but with its recurrence in the period of follow up, and finally, 35 patients had metastatic disease from the very beginning of disease. Tumor originated most commonly in the stomach (41%), small intestine was the second most common location (36%). The mean size of primary tumors was 6.5 cm. The mean duration of follow-up was 60 mo. Multiple parameters were analyzed for their effect on overall survival, but no one reached statistical significance (P = 0.06). Analysis of time to progression/relapse in initially localized disease (univariate analysis), tumor size, mitotic count, Ki-67 and type of d-KIT distribution (cytoplasmic vs membrane/"dot-like") showed statistically significant correlation. In multivariate analysis in the group of patients with localized disease, there were only 2 parameters that have impact on relapse, Ki-67 and SMA (P < 0.0001 and P < 0.034, respectively). Furthermore, Ki-67 was analyzed in localized disease vs localized with recurrence and metastatic disease. It was shown that there is a strict difference between these 2 groups of patients (median value was 2.5 for localized disease vs 10.0 for recurrent/metastatic disease, P < 0.0001). It was also shown that the cut-off value which is still statistically significant in terms of relapse on the level of 6%. The curves for survival on that cut-off level are significantly different (P < 0.04, Cox F). CONCLUSION: Ki-67 presents a significant prognostic factor for GIST recurrence which could be of great importance in evaluating malignant potential of disease.

Reduced E-cadherin expression is a predictor of lower overall survival and metastatic disease in invasive ductal breast cancer.

BACKGROUND: E-cadherin, a transmembrane adhesion molecule, is implicated in the development of many solid tumors as well as in the acquisition of metastatic potential of epithelial tumors. Its clinical use has yet to be established. PATIENTS AND METHODS: The prognostic value of E-cadherin expression in 134 invasive ductal breast carcinoma patients over a 10-year follow-up period was investigated. Additionally, the correlation between E-cadherin expression and other traditional prognostic factors was investigated. RESULTS: A statistically significant influence on overall survival was found for estrogen receptor, tumor size, histological and nuclear grade, HER2, lymph node involvement, vascular invasion, proliferative index, and E-cadherin. E-cadherin expression had a significant impact on overall survival and development of metastases in the group of patients not receiving chemotherapy, while it had no such effect in the group of patients who received chemotherapy. CONCLUSION: We conclude that determination of E-cadherin expression can be used as an adjunct in selecting patients who may benefit from adjuvant chemotherapy in the presence of otherwise favorable prognostic factors.

HER-2/neu oncogene and estrogen receptor expression in non small cell lung cancer patients.

Non-small cell lung cancers are among the leading causes of cancer morbidity and mortality worldwide. The prognosis is usually based on traditional pathohistological parameters and clinical stage, but additional prognostic survival factors have also been sought. The aim of this retrospective study was to explore the membranous expression of HER-2/neu and estrogen receptors in nonsmall cell lung cancers and their relation to survival of patients with non-small cell lung cancers and to traditional prognostic factors. The sample consisted of 132 consecutive, surgically resected patient tissues of non-small cell lung cancers, and the following parameters were examined: HER-2/neu and estrogen receptor expression, as well as the related clinical and pathological features: tumor, nodes, and metastases stage, level of tumor necrosis, histological and nuclear grade, lymphocytic infiltrate, and number of mitoses. HER-2/neu was positive in 28.8% of tumor samples, and estrogen receptor expression was positive in 29.5% of tumors, but neither was significantly associated with the outcome of non-small cell lung cancers. There was a significant association between HER-2/neu and nuclear grade (P=0.01). In addition, the association between estrogen receptor expression and histological type of tumor (P=0.04) and mitotic rate (P=0.008) was found. Kaplan-Meier analysis showed a significant association of patients' overall survival with the tumor node metastasis stage (P<0.001) and the degree of tumor necrosis (P=0.02). Cox proportional hazard regression analysis showed that male gender (P=0.01), histological type (P=0.03), high degree of necrosis (P=0.006), and higher histological grade (P=0.037) were associated with the patients' survival. Our findings indicate that the expression of HER-2/neu and estrogen receptor is less reliable than traditional histological parameters in predicting the survival of patients with non-small cell lung cancers.

[Intraductal papillary mucinous neoplasm of the pancreas: case report and review of the literature]. / Intraduktalna papilarna mucinozna novotvorina gusterace: prikaz slucaja i pregled literature.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a relatively rare clinical entity with a main characteristic being mucus production. Extension of IPMN along pancretic ducts and mucus production lead to ductal obstruction and dilatation, resulting in recurrent episodes of acute pancreatitis. Molecular background of IPMN-a comprises several aberrations, with the K-ras gene mutation being the likely trigger that initiates further genetic changes. Due to its indolent nature, IPMN is most commonly diagnosed in the 7th decade of life. Depending on the histology type, IPMN has a malignant potential. Therefore, surgical therapy remains a "gold standard" of treatment. Insidious, slow progression of the disease and absence of symptoms in a certain number of patients makes diagnostic approach to this entity difficult. In this paper we present a patient with IPMN of the pancreas, in whom the episodes of acute pancreatitis had been present for 22 years.

Prognostic importance of PAI-1 in node negative breast cancer patients--results after 10 years of follow up.

The serine protease urokinase-type plasminogen activator (uPA) and its inhibitor (PAI-1) play key roles in the proteolytic cascade involved in physiological and pathological degradation of the extracellular matrix. The aim of this study was to determine the prognostic importance of PAI-1 expression in tumor cells in node-negative breast cancer patients that did not receive adjuvant chemotherapy. We used immunohistochemistry (IHC) as a detection method. The study retrospectively included 133 ductal invasive breast cancer patients from the Clinical Hospital Center Zagreb, Croatia, surgically treated in a two-year interval (1998-1999) with 10 years of follow up. The Cox proportional hazard regression test with stepwise variable selection was used to calculate the relative effect of investigated data on patients' prognosis. Univariate analysis showed that all investigated factors, such as lymph node involvement (p=0.025), tumor grade (p<0.001), estrogen receptor status (p=0.011), vascular invasion (p=0.001), HER2 overexpression (p<0.001), and proliferative index (p<0.001), had a statistically significant influence on patients' OS. Multivariate statistical analysis showed that only HER-2 (p<0.001) can be considered an independent, statistically significant poor prognostic factor. In patients with negative lymph nodes that did not receive adjuvant chemotherapy, we found a significant correlation in overall survival (p=0.009), which is favorable for PAI-1 negative tumors. In conclusion, it seems that PAI-1 in primary breast cancer tissue correlates with disease aggressiveness and has a strong prognostic impact on primary breast cancer, and is a strong prognostic factor for node-negative patients that did not receive chemotherapy.