Dinka Sundov

P53, MAPK, topoisomerase II alpha and Ki67 immunohistochemical expression and KRAS/BRAF mutation in ovarian serous carcinomas

BackgroundWe investigated the immunohistochemical expression of p53, MAPK, topoisomerase II alpha (topoII alpha) and Ki67 in ovarian serous carcinomas (OSCs) along with mutational analysis for KRAS and BRAF.MethodsEighty one cases of OSCs were reviewed and examined immunohistochemically using antibodies against p53, MAPK, topoII alpha and Ki67. Staining was evaluated as a percentage of immunopositive cells with cut-off levels at 10% for p53 and topoII alpha, and 5% for MAPK. The Ki67 immunoexpression was assessed by means of Olympus Image Analysis System as a percentage of immunopositive cells in 1000 tumor cells. KRAS and BRAF mutational analysis was performed on 73 available microdissected samples.ResultsOf 81 cases of OSCs 13.6% were of low-grade and 86.4% were of high-grade morphology. In the high-grade group there was a significantly higher immunoexpression of p53 (P < 0.001) and topoII alpha (P = 0.001), with Ki67 median 56.5 vs. 19 in low-grade group (P < 0.001). The difference in immunoexpression of active MAPK between low- and high-grade group was also significant (P = 0.003). MAPK positive immunostaining was detected in 63.6% of low-grade vs. 17.1% of high-grade OSCs. The frequency of KRAS mutation was significantly higher in low-grade as compared to high-grade group (P = 0.006). None of the samples had BRAF mutation. In addition, we detected positive MAPK immunoexpression in 13/59 samples with wild-type KRAS, suggesting that activation of MAPK pathway is not ultimately related either to KRAS or BRAF mutation. Seven morphologically high-grade samples (11.7%) showed both KRAS mutation and p53 immunopositivity.ConclusionsAlthough this study is limited by its humble number of low-grade samples, our data fit the proposed dualistic pathway of ovarian carcinogenesis. Mutational analysis for KRAS and BRAF discloses some possible interactions between different tumorigenic pathways of low- and high-grade carcinomas. Immunohistochemical staining for MAPK was not sufficiently sensitive, nor specific, to precisely predict the KRAS mutation. However, it appears to be quite reliable in ruling out a KRAS mutation if the staining is negative.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9283563368804632ZusammenfassungHintergrundWir untersuchten die Immunohistochemische Expression der p53, MAPK, topoisomerase II alpha (topoII alpha) und Ki67 in Ovarialkarzinomen (OSCs) anbei mit Mutationsanalyse für KRAS und BRAF.Methode81 OSCs Fälle wurden analysiert und Immunohistochemisch untersucht mit Antikörper gegen p53, MAPK, topoII alpha und Ki67. Die Färbung war ausgewertet als der Prozent von immunopositiven Zellen mit den “cut-of” Niveau an 10% für p53 und topoII alpha und 5% für MAPK. Die Ki67 Expression war bewertet mittels Olympus Image Analysis System als der Prozent von immunopositiven Zellen in 1000 Tumorzellen. KRAS and BRAF Mutationsanalyse wurde in 73 verfügbaren microdissections Stichproben aufgeführt.ErgebnisseVon 81 OSCs Fälle 13.6% zeigte “low-grade” und 86.4% “high-grade” Morphologie. In der “high-grade” Gruppe war eine statistisch bedeutende höhere Expression von p53 (P < 0.001) und topoII alpha (P = 0.001) mit Ki67 median von 56.5 im Gegensatz zu 19 in der “low-grade” Gruppe (P < 0.001). Die Differenz in Immunoexpression von aktiver MAPK zwischen der “low-grade” und “high-grade” Gruppe war statistisch bedeutend (P = 0.003). MAPK positive Expression war in 63.6% der “low-grade” im Gegensatz von 17.1% der “high-grade” Karzinoms bemerkt. Die Häufigkeit der KRAS Mutation war bedeutend höher in “low-grade” im Verglich zu der “high-grade” Gruppe (P = 0.006). Keiner der Stichproben hate BRAF Mutation. Wir haben auch eine positive MAPK Expression in 13/59 der Stichproben mit “wild-type” KRAS bemerkt, was sugeriert das die Aktivation des MAPK Pfads ist nicht letztmalig mit KRAS oder BRAF verbunden. Sieben der “high-grade” Stichproben (11.7%) waren KRAS Mutation und p53 Expression positive.SchlussworteObwohl diese Studie mit bescheiden Nummer von “low-grade” Stichproben limitiert ist, unsere Daten passen in das dualistische Modell von Ovarial Karzinogenesis. Mutationsanalyse für KRAS und BRAF enthüllen einige mögliche Interaktionen zwischen verschieden tumorigenen Wege von “low”- and “high-grade” Karcinomen.Die Immunohistochemische Expression für MAPK war nicht empfindlich oder spezifisch genüg um den KRAS mutations Status des Tumor genau vorauszusagen.Es scheint das die MAPK Expression ziemlich verlässlich ist in ausschließen der KRAS Mutation, wenn die Expression negative ist.

Correlation Between E-cadherin Immunoexpression and Efficacy of First Line Platinum-Based Chemotherapy in Advanced High Grade Serous Ovarian Cancer

To analyze correlation between immunoexpression of E-cadherin and efficacy of first line platinum-based chemotherapy in patients with advanced-stage high-grade serous ovarian carcinoma. The expression of E-cadherin was analyzed immunohistochemically in formalin-fixed, paraffin-embedded samples from 98 patients with advanced-stage high-grade serous ovarian cancer and related to clinical features (stage according to the International Federation of Gynecology and Obstetrics (FIGO) and residual tumors after initial cytoreductive surgery), response to platinum-based chemotherapy (according to Response Evaluation Criteria in Solid tumors (RECIST 1.1 criteria)), platinum sensitivity (according to platinum free interval (PFI) as platinum-refractory, platinum-resistant and platinum-sensitive) and patients progression free survival (PFS) and overall survival (OS). E-cadherin immunostaining was positive in 74 and negative in 24 serous ovarian carcinomas. E-cadherin immunoreactivity was not associated with FIGO stage, residual tumor after initial cytoreductive surgery and number of chemotherapy cycles. Positive E-cadherin expression predict significantly better response to first line platinum-based chemotherapy (p < 0.001) and platinum sensitivity (p < 0.001). Moreover, positive E-cadherin expression predict significantly longer PFS (p < 0.001) and OS (p < 0.001). The multivariate analysis for OS showed that positive E-cadherin expression is predictor to platinum sensitivity (p < 0.001) and longer OS (p = 0.01). Positive E-cadherin expression seems to be a predictor of better response to first line platinum-based chemotherapy, platinum sensitivity and favorable clinical outcome in patients with advanced-stage serous ovarian cancer. Negative E-cadherin expression was shown to be significant, independent predictor of poorer PFS and OS. E-cadherin as a marker has predictive and prognostic value.

Prognostic significance of MAPK, Topo IIα and E-cadherin immunoexpression in ovarian serous carcinomas

Ovarian cancer accounts for only 3% of all cancers in women but is the most lethal gynaecologic malignancy. Low-grade and high-grade ovarian serous carcinomas (OSCs) represent two different diseases with different prognosis, approaches to detection and treatment. We assessed correlation between, MAPK, topoIIα, E-cadherin immunoexpression and clinicopathological features with overall survival (OS) in OSCs. The study included 81 patients undergoing surgery between January 1995 and December 2005.Formalin fixed paraffin embedded tumour sections were reviewed and examined immunohistochemically using antibodies against MAPK, topoIIα and E-cadherin. The clinicopathological features included: age at surgery, stage according to the criteria of the International Federation of Gynecology and Obstetrics (FIGO), tumour grade, residual disease and vascular invasion. Only ten patients (12.3%) were diagnosed in early FIGO stage of disease. According to morphological criteria, 13.6% of tumor samples were low-grade OSCs and 86.4% were high-grade OSCs. On uninominal analysis, residual disease (p<0.001), E-cadherin (p<0.001), vascular invasion (p=0.002), high-grade morphology (p=0.025) and FIGO stage III-IV (p=0.010) were related to significantly shorter OS. We found no significant association between, MAPK and topoIIα expression and OS. Multinominal analysis revealed that only residual disease (p<0.001) and negative E-cadherin immunoexpression were useful independent predictors of unfavourable clinical outcome and shorter OS.

Optimal follow-up of ovarian cancer patients

Gynecological malignancies account for roughly 10 % of all cancers in women with ovarian cancer as leading cause of death due to gynecological tumors. Surveillance programs of ovarian cancer are primarily based on recurrence rates, timing of recurrence, salvage options, and chances for cure of patient with recurrence. Since there is no prospective, high evidence data on optimal surveillance program after primary treatment of patients with ovarian cancer recommendations are based on review of retrospective data sets. From all the diagnostic tools available, history taking and clinical examination, including gynecological examination, still contribute to the greatest number of recurrence detections. Radiologic and laboratory tests are usually employed when a suspicion of recurrence is raised. Follow-up plan should be tailored according to the estimated risk of relapse for individual patient.