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Virchows Archiv | 2004

Molecular genetic pathways in various types of endometrial carcinoma: from a phenotypical to a molecular-based classification

Sigurd Lax

Two types of endometrial carcinoma are distinguished with respect to biology and clinical course. Type-I carcinoma is related to hyperestrogenism by association with endometrial hyperplasia, frequent expression of estrogen and progesterone receptors and younger age, whereas type-II carcinoma is unrelated to estrogen, associated with atrophic endometrium, frequent lack of estrogen and progesterone receptors and older age. Histologically, endometrioid and mucinous carcinomas are considered type I, serous and clear cell carcinomas type II. Molecular data from multiple studies support the hypothesis of different genetic pathways in the development of endometrioid and serous carcinoma. The most frequent genetic alteration in endometrioid carcinoma is PTEN inactivation by mutation, followed by microsatellite instability (MIN) and mutations of K-ras and β-catenin. PTEN and K-ras mutations and MIN are considered early events, occurring in a subset of atypical endometrial hyperplasia, whereas p53 mutation is considered a late event, during progression of about 10–20% of endometrioid carcinomas. In serous carcinoma, p53 mutation is the most frequent genetic alteration, followed by inactivation of p16 and e-cadherin and amplification of her2/neu. p53 mutation occurs in endometrial intraepithelial carcinoma, the putative precursor of serous carcinoma. Considering these genetic pathways, the current histological classification of endometrial carcinoma is molecular based.


Human Pathology | 1998

Clear cell carcinoma of the endometrium is characterized by a distinctive profile of p53, Ki-67, estrogen, and progesterone receptor expression.

Sigurd Lax; Ellen S. Pizer; Brigitte M. Ronnett; Robert J. Kurman

This study was designed to analyze certain clinicopathological features and the profile of p53, Ki-67, estrogen (ER), and progesterone (PR) receptor expression of clear cell carcinoma of the endometrium and to determine whether the pathogenesis of clear cell carcinoma can be accommodated by a dualistic model of endometrial carcinogenesis. In this model, endometrioid carcinoma develops from endometrial hyperplasia under unopposed estrogenic stimulation, and serous carcinoma develops in atrophic endometrium from a putative precursor lesion designated endometrial intraepithelial carcinoma (EIC). Twenty-one clear cell carcinomas of the endometrium were analyzed and compared with 77 endometrioid carcinomas of all grades and 30 serous carcinomas. Clear cell carcinomas showed a distinctive immunoprofile characterized by immunonegativity for ER and PR, low immunoreactivity for p53, and a high Ki-67 proliferation index. ER, PR, and Ki-67 expression were similar to serous carcinoma, but p53 expression was significantly lower in clear cell carcinoma (P < .05). ER and PR expression were significantly lower, and the Ki-67 proliferation index was significantly higher in clear cell carcinoma compared with endometrioid carcinomas (P < .05). p53 expression tended to be higher in clear cell carcinoma compared with endometrioid carcinoma, but the difference was not statistically significant. In contrast to endometrioid carcinoma, clear cell carcinoma was rarely associated with endometrial hyperplasia and serous carcinoma was not. Subdividing clear cell carcinoma morphologically into one that resembled serous carcinoma (clear cell carcinoma with serous features) and another that did not (typical clear cell carcinoma) showed that clear cell carcinoma with serous features had a higher Ki-67 proliferation index than typical clear cell carcinoma, although expression of ER, PR, and p53 were similar. Clear cell carcinoma with serous features was associated with EIC in 50% and was not associated with endometrial hyperplasia. In contrast, typical clear cell carcinoma was associated with endometrial hyperplasia in 40% and was not associated with EIC. In summary, this study provides evidence that clear cell carcinoma of the endometrium, like serous carcinoma, is estrogen independent and shows a high Ki-67 proliferation index. In contrast to serous carcinoma, strong p53 expression occurred less frequently in clear cell carcinoma and predominantly in clear cell carcinoma with serous features. The findings suggest that the molecular events that underlie the development of clear cell carcinoma differ from those of endometrioid and serous carcinoma.


Human Pathology | 1998

Comparison of estrogen and progesterone receptor, Ki-67, and p53 immunoreactivity in uterine endometrioid carcinoma and endometrioid carcinoma with squamous, mucinous, secretory, and ciliated cell differentiation

Sigurd Lax; Ellen S. Pizer; Brigitte M. Ronnett; Robert J. Kurman

An analysis of 77 uterine endometrioid carcinomas was performed to compare pure endometrioid carcinomas and endometrioid carcinomas with various types of cellular differentiation for the expression of estrogen (ER) and progesterone (PR) receptors, p53, and Ki-67 and to correlate these findings with clinicopathologic features. Forty-three pure endometrioid carcinomas and 34 endometrioid carcinomas displaying additional types of cellular differentiation in at least 10% of the tumor (16 squamous, 11 mucinous, four ciliated cell, and three secretory) were analyzed. In 8 of the 16 tumors with squamous differentiation, the squamous component was histologically benign (low grade), and in eight tumors it was histologically malignant (high grade). In tumors showing various types of cellular differentiation except those with a high-grade squamous component, comparison of the endometrioid glandular component with the squamous, mucinous, secretory, and ciliated cell components showed that ER/PR, Ki-67, and p53 expression were generally higher in the glandular component compared with the various differentiated components. These findings parallel the changes that occur in the endometrium in the secretory phase of the menstrual cycle and, therefore, suggest that the differentiated components have undergone terminal differentiation. In contrast, in endometrioid carcinomas with a high-grade squamous component, Ki-67 and p53 expression were the same in the glandular and squamous components suggesting that squamous epithelium in these tumors represented another pathway of cellular differentiation but not one that was terminally differentiated. Endometrioid carcinomas with a high-grade squamous component had significantly higher grade (P = .002), stage (P < .001), cellular proliferation index (P = .0005), and worse outcome (P = .0009) compared with tumors with the other types of cellular differentiation, including those with a low-grade squamous component and pure low-grade endometrioid carcinomas. In addition, carcinomas with a high-grade squamous component occurred in older women and were more frequently associated with atrophic endometrium and less replacement hormone therapy, but the differences were not statistically significant. In conclusion, endometrioid carcinomas with various types of cellular differentiation can be broadly divided into two groups. Tumors with mucinous, secretory, and ciliated cell differentiation and those with a low-grade squamous component are similar to pure low-grade endometrioid carcinomas in that most have high ER and PR expression, low cellular proliferation indices, low p53 immunoreactivity, and good prognosis. In contrast, endometrioid carcinomas with a high-grade squamous component lack expression of ER and PR, have high cellular proliferation indices, often express p53, and have a prognosis similar to poorly differentiated endometrioid carcinomas.


International Journal of Molecular Sciences | 2013

Targeting Signaling Pathways in Epithelial Ovarian Cancer

Elisabeth Smolle; Valentin Taucher; Martin Pichler; Edgar Petru; Sigurd Lax; Johannes Haybaeck

Ovarian carcinoma (OC) is the most lethal gynecological malignancy. Response to platinum-based chemotherapy is poor in some patients and, thus, current research is focusing on new therapy options. The various histological types of OC are characterized by distinctive molecular genetic alterations that are relevant for ovarian tumorigenesis. The understanding of these molecular pathways is essential for the development of novel therapeutic strategies. Purpose We want to give an overview on the molecular genetic changes of the histopathological types of OC and their role as putative therapeutic targets. In Depth Review of Existing Data In 2012, the vascular endothelial growth factor (VEGF) inhibitor, bevacizumab, was approved for OC treatment. Bevacizumab has shown promising results as single agent and in combination with conventional chemotherapy, but its target is not distinctive when analyzed before treatment. At present, mammalian target of rapamycin (mTOR) inhibitors, poly-ADP-ribose polymerase (PARP) inhibitors and components of the EGFR pathway are in the focus of clinical research. Interestingly, some phytochemical substances show good synergistic effects when used in combination with chemotherapy. Conclusion Ongoing studies of targeted agents in conjunction with chemotherapy will show whether there are alternative options to bevacizumab available for OC patients. Novel targets which can be assessed before therapy to predict efficacy are needed. The assessment of therapeutic targets is continuously improved by molecular pathological analyses on tumor tissue. A careful selection of patients for personalized treatment will help to reduce putative side effects and toxicity.


Clinical Cancer Research | 2014

A Functional Germline Variant in GLI1 Implicates Hedgehog Signaling in Clinical Outcome of Stage II and III Colon Carcinoma Patients

Joanna Szkandera; Martin Pichler; Gudrun Absenger; Michael Stotz; Melanie Weissmueller; Hellmut Samonigg; Martin Asslaber; Sigurd Lax; Gerhard Leitner; Thomas Winder; Wilfried Renner; Armin Gerger

Purpose: Cumulating evidence indicates that germline variants in the Wnt, Notch, and Hedgehog pathways are involved in colon carcinoma progression and metastasis. We investigated germline polymorphisms in a comprehensive panel of Wnt, Notch, and Hedgehog pathway genes to predict time to recurrence (TTR) and overall survival in patients with stage II and III colon carcinoma. Experimental Design: A total of 742 consecutively collected patients with stage II and III colon carcinoma were included in this retrospective study. Genomic DNA was analyzed for 18 germline polymorphisms in Wnt, Notch, and Hedgehog pathway genes (SFRP, DKK 2 and 3, AXIN2, APC, MYC, TCF7L2, NOTCH2, and GLI1) by TaqMan 5′-exonuclease assays. Results: In univariate analysis, the homozygous mutant variant of GLI1 rs2228226 G>C was significantly associated with decreased TTR in a recessive genetic model after adjustment for multiple testing [HR = 2.35; confidence interval (95% CI), 1.48–3.74; P < 0.001] and remained significant in multivariate analysis including clinical stage, lymphovascular-, vascular-, and perineural-invasion (HR = 2.43; CI 95%, 1.52–3.87; P < 0.001). In subanalyses, the association was limited to patients with surgery alone (HR = 3.21; CI 95%, 1.59–6.49; P = 0.001), in contrast with patients with adjuvant chemotherapy (HR = 0.82; CI 95%, 0.35–1.95; P = 0.657). When the subgroup of patients with “high-risk” GLI1 rs2228226 C/C genotype was analyzed, no benefit of adjuvant 5-fluorouracil–based chemotherapy could be found. Conclusion: This is the first study identifying GLI1 rs2228226 G>C as an independent prognostic marker in patients with stage II and III colon carcinoma. Prospective studies are warranted to validate our findings. Clin Cancer Res; 20(6); 1687–97. ©2014 AACR.


Drug Metabolism and Disposition | 2008

CYP1B1 Is Not a Major Determinant of the Disposition of Aromatase Inhibitors in Epithelial Cells of Invasive Ductal Carcinoma

Mostafizur Rahman; Sigurd Lax; Carrie Hayes Sutter; Quynh T. Tran; Gaylene Stevens; Gary L. Emmert; Jose Russo; Richard J. Santen; Thomas R. Sutter

CYP1B1 and CYP19 (aromatase) have been shown to be expressed in breast tumors. Both enzymes are efficient estrogen hydroxylases, indicating the potential for overlapping substrate and inhibitor specificity. We measured the inhibition properties of aromatase inhibitors (AIs) against CYP1B1-catalyzed hydroxylation of 17β-estradiol (E2) to determine whether CYP1B1 affects the disposition of AIs. In addition, we estimated the frequency of coexpression of these enzymes in breast tumor epithelium. Immunohistochemical analyses of CYP19 and CYP1B1 in a panel of 29 cases of invasive ductal carcinoma of the breast showed epithelial cell staining for CYP19 in 76% and for CYP1B1 in 97% of the samples. Statistical analysis showed no significant correlation (0.33) for positive expression of CYP19 and CYP1B1 (p > 0.07). CYP1B1 inhibition was determined for two steroidal inhibitors: formestane and exemestane and five nonsteroidal inhibitors: aminoglutethimide, fadrozole, anastrozole, letrozole, and vorozole. Of the seven compounds tested, only vorozole exhibited inhibition of CYP1B1 activity with IC50 values of 17 and 21 μM for 4-hydroxy estradiol and 2-hydroxy estradiol, respectively. The estimated Ki values of vorozole for E2 4- and 2-hydroxylation were 7.26 and 6.84 μM, respectively. Spectrophotometric studies showed that vorozole was a type II inhibitor of CYP1B1. This study shows that with the exception of vorozole, the aromatase inhibitors are selective for CYP19 relative to CYP1B1. Thus, although both CYP19 and CYP1B1 are expressed in a high percentage of breast cancers, CYP1B1 is not a major determinant of the disposition of AIs.


Radiotherapy and Oncology | 2018

The European Society of Gynaecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology guidelines for the management of patients with cervical cancer

David Cibula; Richard Pötter; François Planchamp; Elisabeth Åvall-Lundqvist; D. Fischerova; Christine Haie Meder; Christhardt Köhler; Fabio Landoni; Sigurd Lax; Jacob Christian Lindegaard; Umesh Mahantshetty; Patrice Mathevet; W. Glenn McCluggage; Mary McCormack; Raj Naik; Remi A. Nout; Sandro Pignata; Jordi Ponce; Denis Querleu; Francesco Raspagliesi; Alexandros Rodolakis; Karl Tamussino; Pauline Wimberger; Maria Rosaria Raspollini

BACKGROUNDnDespite significant advances in the screening, detection, and treatment of preinvasive cervical lesions, invasive cervical cancer is the fifth most common cancer in European women. There are large disparities in Europe and worldwide in the incidence, management, and mortality of cervical cancer.nnnOBJECTIVEnThe European Society of Gynaecological Oncology (ESGO), the European Society for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly develop clinically relevant and evidence-based guidelines in order to improve the quality of care for women with cervical cancer across Europe and worldwide.nnnMETHODSnThe ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of cervical cancer (23 experts across Europe). To ensure that the guidelines are evidence based, the current literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 159 international reviewers, selected through ESGO/ESTRO/ESP and including patient representatives.nnnRESULTSnThe guidelines cover comprehensively staging, management, and follow-up for patients with cervical cancer. Management includes fertility sparing treatment; stage T1a, T1b1/T2a1, clinically occult cervical cancer diagnosed after simple hysterectomy; early and locally advanced cervical cancer; primary distant metastatic disease; cervical cancer in pregnancy; and recurrent disease. Principles of radiotherapy and pathological evaluation are defined.


Virchows Archiv | 2018

The European Society of Gynaecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology Guidelines for the Management of Patients with Cervical Cancer

David Cibula; Richard Pötter; François Planchamp; Elisabeth Åvall-Lundqvist; D. Fischerova; Christine Haie-Meder; Christhardt Köhler; Fabio Landoni; Sigurd Lax; Jacob Christian Lindegaard; Umesh Mahantshetty; Patrice Mathevet; W. Glenn McCluggage; Mary McCormack; Raj Naik; Remi A. Nout; Sandro Pignata; Jordi Ponce; Denis Querleu; Francesco Raspagliesi; Alexandros Rodolakis; Karl Tamussino; Pauline Wimberger; Maria Rosaria Raspollini

Background:Despite significant advances in the screening, detection, and treatment of preinvasive cervical lesions, invasive cervical cancer is the fifth most common cancer in European women. There are large disparities in Europe and worldwide in the incidence, management, and mortality of cervical cancer.Objective:The European Society of Gynecological Oncology (ESGO), the European Society for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly develop clinically relevant and evidence-based guidelines in order to improve the quality of care for women with cervical cancer across Europe and worldwide.Methods:The ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of cervical cancer (23 experts across Europe). To ensure that the guidelines are evidence based, the current literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 159 international reviewers, selected through ESGO/ESTRO/ESP and including patient representatives.Results:The guidelines cover comprehensively staging, management, and follow-up for patients with cervical cancer. Management includes fertility sparing treatment; stage T1a, T1b1/T2a1, clinically occult cervical cancer diagnosed after simple hysterectomy; early and locally advanced cervical cancer; primary distant metastatic disease; cervical cancer in pregnancy; and recurrent disease. Principles of radiotherapy and pathological evaluation are defined.


Oncotarget | 2018

BRCA1/2 and TP53 mutation status associates with PD-1 and PD-L1 expression in ovarian cancer

Verena Wieser; Inge Gaugg; Martina Fleischer; Giridhar Shivalingaiah; Soeren Wenzel; Susanne Sprung; Sigurd Lax; Alain G. Zeimet; Heidelinde Fiegl; Christian Marth

Checkpoint molecules such as programmed cell death protein-1 (PD-1) and its ligand PD-L1 are critically required for tumor immune escape. The objective of this study was to investigate tumoral PD-1 and PD-L1 mRNA-expression in a cohort of ovarian cancer (OC) patients in relation to tumor mutations. We analyzed mRNA expression of PD-1, PD-L1 and IFNG by quantitative real-time PCR in tissue of 170 patients with low grade-serous (LGSOC), high-grade serous (HGSOC), endometrioid and clear cell OC compared to 28 non-diseased tissues (ovaries and fallopian tubes) in relation to tumor protein 53 (TP53) and breast cancer gene 1/2 (BRCA1/2) mutation status. TP53-mutated OC strongly expressed PD-L1 compared to TP53 wild-type OC (p = 0.028) and BRCA1/2-mutated OC increasingly expressed PD-1 (p = 0.024) and PD-L1 (p = 0.012) compared to BRCA1/2 wild-type OC. For the first time in human, we noted a strong correlation between tumoral IFNG and PD-1 or PD-L1 mRNA-expression, respectively (p < 0.001). OC tissue increasingly expressed PD-1 compared to healthy controls (vs. ovaries: p < 0.001; vs. tubes: p = 0.018). PD-1 and PD-L1 mRNA-expression increased with higher tumor grade (p = 0.008 and p = 0.027, respectively) and younger age (< median age, p = 0.001). Finally, in the major subgroup of our cohort, FIGO stage III/IV HGSOC, high PD-1 and PD-L1 mRNA-expression was associated with reduced progression-free (p = 0.024) and overall survival (p = 0.049) but only in the univariate analysis. Our study suggests that in OC PD-1/PD-L1 mRNA-expression is controlled by IFNγ and affected by TP53 and BRCA1/2 mutations. We suggest that these mutations might serve as potential predictive factors that guide anti-PD1/PD-L1 immunotherapy.


Virchows Archiv | 2018

Miniseries of reviews: gynecological pathology

Sigurd Lax

Virchows Archiv will regularly publish issues with a coordinated set of reviews in areas with important recent developments, but in volume insufficient to make it into a full review issue. This issue contains such a miniseries of three review articles in the area of gynecological pathology, two of which are dealing with novel developments in molecular pathology and histopathology of the uterus while the third addresses the diagnostically challenging subject of benign proliferations of the endometrium. Goebel et al. (https://doi.org/10.1007/s00428-017-2279-8) describe the evolution of the classification of endometrial carcinoma, which used to be purely descriptive but is now molecularly based, as a result of the rapid development of molecular pathology [1]. They present a snap-shot of the current state of the art of molecular pathology of the endometrium as well as a vision on putative further developments, following integration of new knowledge emerging from molecular studies into diagnostic pathology. Based on the results of molecular analysis of endometrial carcinoma in the context of The Cancer Genome Atlas (TCGA) project and using immunohistochemistry and sequencing technologies, a diagnostic algorithm was developed which allows recognition of carcinoma types beyond histology with distinct biological behaviour [2]. This replaces a purely histopathological classification by one that is more molecularly based, comparable to what has happened in breast and lung cancer. This new classification will provide more precise prognostic information as well as predictive information to guide targeted therapy [3, 4]. Although most endometrial carcinomas do not need systemic treatment, molecular classification goes beyond histology in defining tumour subtypes with excellent prognosis, such as those with a DNA polymerase ɛ (POLE) domain mutation, or with poor prognosis, such as the mixed endometrial carcinomas with a low-grade serous-like component, which will both profit from a “tailored” approach to treatment. The TCGA data segregated endometrial carcinoma into four prognostic categories, but this is not in conflict with the traditional type 1 and type 2 endometrial carcinoma [1] as it only identifies one further subtype, the small group of POLE mutated carcinomas which have an excellent prognosis. The microsatellite instable and the low copy number alteration groups cluster together, since they show similar prognosis and represent the two major pathways involved in type 1 carcinomas, whereas the high copy number alteration serous-like carcinomas represent the type 2 carcinomas. The two type model as originally proposed by Bokhman was based on clinical features and biology. POLE mutated carcinomas fit well in type 1 endometrial carcinomas but further clinicopathological and molecular correlations will await data from additional studies [5, 6]. The strength of an updated molecular model for endometrial carcinoma is its increased clinical impact with transition from bench and lecture hall to bedside. The biggest challenge will be implementation of this novel diagnostic algorithm into daily practice, particularly in tertiary centres and low income countries [7]. In contrast to endometrial carcinoma, a molecular signature with prognostic impact has as yet not been identified for endocervical adenocarcinoma. Instead, it has been found that the the biology of endocervical adenocarcinomas is reflected in its pattern of growth (https://doi.org/10.1007/s00428-0182312-6). Three growth patterns, known as Silva patterns (named after the senior author of the first description, Elvio Silva), have been described (non-destructive, focally destructive and diffusely destructive) [8, 9], which reportedly correlate with the frequency of lymph node metastases and local recurrence and will have strong impact on treatment. Knowledge about this growth pattern-based classification has been further broadened in recent years by several multicenter international collaborative studies. This pattern-based model seems simple but is a rather smart * Sigurd F. Lax [email protected]; [email protected]

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Martin Pichler

Medical University of Graz

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Armin Gerger

Medical University of Graz

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Hellmut Samonigg

Medical University of Graz

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Karl Tamussino

Medical University of Graz

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Wilfried Renner

Medical University of Graz

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