[Sentinel node biopsy in colorectal carcinoma--pilot study]. / Biopsie sentinelové uzliny u kolorektálního karcinomu--pilotní studie.

BACKGROUND: Sentinel lymph node biopsy is a widely accepted method for staging melanoma and breast cancer in indicated cases. However, the use of the method in colorectal cancer is under clinical investigation. The aim of the pilot study was to introduce the technique into the surgical practice in colon carcinoma, to determine the feasibility and potential problems and to evaluate the first experience. METHODS: Twenty patients with colon cancer underwent lymphatic mapping and sentinel node biopsy using blue dye, fluorescein or lymphoscintigraphy followed by standard surgical resection. The acquired sentinel nodes were investigated with both standard hematoxylin-eosin staining and immunohistochemical staining for cytokeratin. RESULTS: Lymphatic mapping adequately identified at least one sentinel node (SN) intraoperatively or by a modified ex vivo technique in 20 patients (100%). The average number of SN was 1.5 (range 1-3), non-SN 13.6 (range 1-38) per patient. SN correctly predicted the regional lymphatic basin status in 14 cases (70%). The false negative rate was 40%. No patient has been upstaged on the basis of immunohistochemical staining. CONCLUSIONS: Lymphatic mapping and sentinel node biopsy in colon cancer is feasible and safe method with a high SN identification rate. The role and significance of sentinel node biopsy in colon cancer is not as clear as its role in other tumors and remains controversial. Further large prospective studies with standardized techniques are needed to evaluate the potential benefit of this new method.

Androgen receptor in prostate carcinoma: immunohistochemical and ligand saturation analyses.

Status of androgen receptor (AR) in prostate carcinoma is biologically important. Therefore, more methods assessing AR abnormalities are warranted. Immunohistochemical (IHC) and ligand saturation (LSA) assays were not compared in details. AR in 53 cases were tested by monoclonal antibody (Ab) F39.4.1 (Biogenex), polyclonal Ab N-20 (Santa Cruz) and by ligand saturation analysis with (3)H-methyltrienolon. Statistical analyses were performed with Spearman's nonparametric rank test including neoadjuvant therapy subgroups treated by antiandrogens, combined androgen blockade (22 cases; flutamide with gosereline) or without therapy. By using monoclonal Ab we found AR positive tumor nuclei in 46 cases. Mean of positives was 64%, median 75%. The polyclonal Ab was not sufficiently specific. With LSA AR were found in 43 cases. Mean level was 6.6 fmol/mg, median 5.5 fmol/mg. Comparing IHC with LSA, we noted correlation trend only for the monoclonal Ab (r=0.35; p=0.02). With thresholds 70% positive nuclei for IHC and 6 fmol/mg for LSA, there were 66% and 43% cases positive with IHC and LSA, respectively. The LSA and IHC positives did not show significant agreement, concordance level being 58% only. We found significant IHC-LSA correlation (r=0.68; p=0.004) solely in combined androgen blockade subgroup with 82% level concordance. Our study has demonstrated that AR IHC and LSA are independent complementary methods. Significant correlation between LSA and IHC show only cases treated with combined androgen blockade. An explanation hypothesis is discussed concerning LH-RH influence on free AR capable of ligand binding. IHC as well as LSA have specific biologic significance and may be useful for prostate cancer diagnostic and therapy.

Malignant melanoma associates with deficient IFN-induced STAT 1 phosphorylation.

STAT 1, a member of signal transducers and transcription activators of STAT family proteins, has been implicated as important mediator of IFN signaling. Functional activation of STAT 1 requires tyrosine and serine phosphorylation. Defects in its expression or activation in response to IFNs were observed in numerous pathological conditions including cancer. To further explore cancer-associated impaired STAT 1 response to IFNs, the inducibility of serine (S 727) and tyrosine (Y 701) phosphorylation by IFN-alpha/-gamma was assessed in 21 melanoma cell lines and in 35 primary cultures derived from melanoma patients. STAT 1 levels and inducibility of its activated phospho-forms were detected by Western analysis using specific polyclonal and monoclonal antibodies. All cell lines as well as patient melanoma samples expressed STAT 1 with variable signal intensity. Significant impaired IFN-induced STAT 1 S 727 phosphorylation was observed in both model systems with average of 77% of non-responders recorded in patient melanoma cells and 76% in melanoma cell lines. Failure of PY 701 induction occurred in patient samples (63% after IFN-alpha and 34% after IFN-gamma induction) and to a lesser degree in cell lines (i.e. response absence to IFN-alpha in 5 and to IFN-gamma in 2 melanoma lines). Our study demonstrates STAT 1 functional abnormalities in melanoma cells. On the basis of detailed analyses of patient melanoma cells with respect to the inducibility of STAT 1 phosphorylation by IFNs, four categories of patients could be distinguished: a) activation on both S 727 and Y 701, b) not inducible response, c) activation on Y 701 but not on S 727, d) heterogeneous response. Clinical study is now in progress to establish the significance of in vitro STAT 1 activation for predicting the response to IFN-based therapy and to explore biological consequences in cases responding in vitro to IFN-induced STAT 1 activation on only one of the critical amino acid residues.

Malignant melanoma associates with Th1/Th2 imbalance that coincides with disease progression and immunotherapy response.

The immunological dysfunction associated with human cancer is well known phenomenon. It comprises number of pathological changes within immune network including imbalance in cytokines of Th1/Th2 origin. The objectives of our study were (i) to evaluate the abnormalities in serum levels of selected cytokines in malignant melanoma patients with regional lymph node metastases as compared to normal values, (ii) to examine the relationship between postoperative cytokine levels and disease progression and (iii) to correlate cytokine profile changes during IFN-alpha therapy with the disease progression and potential therapeutical response. Nine Th1/Th2 related cytokines and sIL-2R were determined in 26 malignant melanoma patients at clinical stage III prior and during adjuvant immunotherapy. Control group consisted of 26 healthy persons. Patients were treated with rIFN-alpha according to EORTC Melanoma group protocol 18952. Cytokines were quantified in patients sera using commercial ELISA kits. Majority of melanoma patients showed significantly lower values of IL-2 and IFN-gamma and pathologically elevated levels of IL-4, IL-6, IL-10 as compared to healthy subjects what indicates disease associated Th1/Th2 imbalance. In addition increased IL-12 and IL-15 values were noted in some patients (54% and 27%, respectively). All patients who manifested early relapse during immunotherapy had significantly lower pretreatment levels of IL-2 and IL-12 than those remaining without progression and probably benefiting from the treatment. Cytokine changes during immunotherapy disclosed that decreases in IL-2 and IL-12 and raises in IL-6 and IL-10 values occurred at least one month prior to relapse. Moreover, the continuous elevation of TNF-alpha and sIL-2R could be observed in patients who remained without progression during 10 months lasting immunotherapy. Our data illustrate that malignant melanoma associates with Th1/Th2 perturbances which are directed towards extended Th2 responses and that measurement of selected cytokines of Th1/Th2 category may be used as an early signal of disease deterioration and for evaluation of immunotherapy response.

[Tumor biopsy--a trivial matter or a basic procedure?]. / Biopsie nádoru--banalita, nebo zásadní výkon?

The surgeon is frequently faced with the task of bioptic sampling of tissues from patients with tumourous diseases. The importance of such frequently minor procedures is incorrectly underrated. The importance of biopsy is in the foreground in particular at present at a time of individualization of treatment of malignant tumours, based on the development of new diagnostic-therapeutic methods. The bioptic specimen is the fundamental link in the basic decision--benignity or malignity--and also a unique source for assessment of prognostic and predictive factors on the basis of which we select the optimal therapeutic procedure. Contrary to current histopathological examination where the principles of correct collection of tissues specimens are generally known, in recent years the importance of molecular examinations is increasing where the surgeon must respect certain different principles to make the sampling successful. The authors working in a department of surgical oncology along with authors from specialized laboratories formulate rules of correct implementation of biopsies and transport of biological material in conjunction with recent laboratory methods, and based on examples of their own practice, they demonstrate how the initial approach of the surgeon can influence in a decisive way the correct diagnosis and therapeutic procedure in oncological patients.

Quantitative determination of telomerase activity in breast cancer and benign breast diseases.

Telomerase plays an important role in maintaining the stability of chromosomes. This ribonucleoprotein prevents chromosome ends (telomeres) from gradual loss with each cell division. It enables tumor cells to maintain telomere length, allowing indefinite replicative capacity. Telomerase activity has been detected in the majority of tumor and germ cells and in immortalized cell lines. Quantitative telomerase PCR-ELISA (TeloTAGGG Telomerase PCR ELISA(PLUS)) was evaluated for distinguishing benign and malignant breast tissue. Activity of telomerase was determined in 27 samples of fibrocystic and dysplastic tissues, 28 fibroadenomas and phylloid tumors, and 154 breast cancer tissues; 59 specimens were analyzed retrospectively. Analytical precision and linearity of the assay was tested using breast carcinoma cell line ZR-75-1 and breast tumor tissue extracts. About 4% of tumor samples were excluded from analysis due to interferences in the PCR reaction. Relative telomerase activity differed significantly in the groups of dysplastic tissues, fibroadenomas and carcinomas. The highest activity was found in breast cancer tissue. This method can identify breast cancer tissue with 73% clinical sensitivity and 93% specificity as compared to benign breast tumors. We did not find a correlation between telomerase activity and the tissue levels of estrogen and progesterone receptors, HER-2/neu oncoprotein concentration, tumor size, and lymph node positivity. Probability of disease-free survival was significantly lower for patients with telomerase activity higher than median value. As the assay for telomerase activity has very high analytical sensitivity and high specificity for cancer cells, this routinely used method may prove useful for distinguishing malignant phenotype of breast tissues.

Bone marrow micrometastases in patients with stage I-II localised prostate cancer.

Prostate cancer commonly metastasises to the bones. Detection of bone marrow micrometastases (BMM) may give important information that helps define treatment strategies. This study was undertaken to analyse BMM in early prostate cancer patients and to determine the accuracy of immunohistochemical (IHC) and morphological methods in detecting cancerous cells. Preoperative core bone marrow biopsy (BMB) was performed in 103 patients with T1-2, N0, M0 prostate cancer after neoadjuvant androgen blockade. BMB were examined by IHC using monoclonal antibodies for cytokeratins (CK) (18, 19, PAN) and by cytomorphology of IHC-positive cells. In 103 patients, BMM were detected in 2 cases (2%) and an additional 3 cases (3%) were classified as suspicious. IHC alone revealed positive cells in 19 patients (18%). Cytomorphology disclosed IHC false-positive staining of some apparently normal bone marrow elements such as plasmocytes. The study shows a rather low rate of BMM in early prostate cancer. It also stresses the importance of cytomorphology as an adjunct to IHC as IHC alone may not be sufficient and appropriate for BMM detection.

Correlation between apoptotic figure counting and the TUNEL technique.

OBJECTIVE: To compare histologic detection of apoptotic (AP) figures and terminal transferase UTP nick end labeling (TUNEL) detection in colorectal carcinomas and lymphomas. STUDY DESIGN: We evaluated the percentage of AP cells by AP figure counting and by the TUNEL technique in formalin-paraffin material from 39 tumors--29 colorectal carcinomas and 10 non-Hodgkin's lymphomas. The Lucia G image analysis system (Laboratory Imaging, Prague, Czech Republic) was used for cellularity evaluation and AP counting. RESULTS: On average, 0.81 +/- 0.5% AP cells were detected by figure counting; 0.91 +/- 0.35% were identified by TUNEL. A statistically high correlation between these techniques was found using Pearson's correlation coefficient (r = .56, P < .001). TUNEL, although probably more sensitive, was difficult to standardize. CONCLUSION: AP figure counting seems to be the method of choice for routine work, particularly because of its cost effectiveness and reproducibility.

p53 status in breast carcinomas revealed by FASAY correlates well with p53 protein accumulation determined by immunohistochemistry.

The prognostic and predictive value of p53 mutation in breast cancer is still conflicting. The choice of the p53 status detection method may account for some discrepancies. In this pilot study we compared two differently-based methods for detection of p53 alteration in 32 breast carcinoma samples: the immunohistochemical method using Bp53, DO1 and DO11 monoclonal antibodies for analysis of the p53 protein accumulation in cell nuclei and the functional method FASAY. FASAY - functional analysis of the separated alleles in yeast - tests the capability of the human p53 to transactivate a reporter with a p53 binding site RGC driving the ADE2 gene in yeast. In our group the percentage of breast cancers with accumulated p53 protein was 50%, as well as percentage of mutant p53 scored by FASAY was 50%. Although the agreement of both methods, when comparing the results of individual patients was high (94%), our results show that immunohistochemistry does not reflect the p53 status quite exactly.