Molecular profiling of endometrial carcinoma : closing in on personalized medicine

The ultimate goal of personalized medicine is to offer optimal treatment to each patient while avoiding under- and overtreatment. At present, clinicopathological risk algorithms determine whether lymph node dissection or postoperative radiotherapy/chemotherapy are indicated for a patient with endometrial carcinoma (EC). As traditional risk assessment methods suffer from limited accuracy, researchers are trying to find molecular biomarkers that could help guide the treatment of EC. In 2013, a landmark study by the Cancer Genome Atlas research group (TCGA) identified four prognostic molecular subgroups of EC. The study cohort of this thesis consisted of unselected EC patients who were surgically treated at Helsinki University Hospital between 2007 and 2012. Tumor samples from 842 patients were included in a tissue microarray. The aim of this thesis was to investigate clinicopathological and prognostic significance of L1 cell adhesion molecule (L1CAM) and MLH1 methylation status in EC. In addition, we explored the differences between the two largest molecular subgroups of EC with regard to the prognostic impact of individual risk factors and the expression of an immunotherapy target molecule, programmed death ligand 1 (PD-L1). I: Tumoral L1CAM positivity was associated with more frequent distant relapses and independently predicted poor prognosis in endometrioid EC but not in non-endometrioid EC. L1CAM may enhance the accuracy of post-operative risk stratification algorithms guiding adjuvant treatment of EC. II: Integrating preoperatively assessed tumoral L1CAM with the conventional risk assessment models did not facilitate stratification of patients to lymphadenectomy. III: In multiplex immunohistochemistry, PD-L1 expression was more frequent in intratumoral immune cells (27.7%) than in carcinoma cells (8.6%). Within the molecular subgroups the relative frequency of PD-L1 positivity was higher in POLE-mutated and mismatch repair deficient (MMRd) tumors than in the other molecular groups (p53 abnormal and no specific molecular profile). Further, we found differences in PD-L1 expression across histological subgroups. IV: MMR deficiency correlated with several clinicopathological risk factors. Methylated phenotype was associated with older age and larger tumor size. Methylated MMRd phenotype predicted poor disease-specific survival compared with MMR proficient EC, but the difference with non-methylated MMRd EC was not significant. V: Our study confirmed the survival differences between molecular subgroups originally proposed by TCGA: POLE-mutated EC had an excellent prognosis, followed by NSMP, MMRd, and the more aggressive p53 abnormal EC. In multivariable analysis adjusting for conventional risk factors, NSMP and MMRd molecular subgroups did not present significant survival differences. Interaction analysis confirmed differences between NSMP and MMRd with regard to prognostic impact of individual risk factors. This thesis identifies several molecular factors that may facilitate treatment planning of EC. Given their distinct prognosis and pathogenetic mechanisms, molecular EC subgroups should probably be regarded as disease entities of their own. This way optimal risk stratification algorithms can be determined leading to personalized and cancer type-specific treatment of patients with EC.Suurella osalla kohtusyöpäpotilaista tauti ei ole levinnyt kohdun ulkopuolelle, jolloin syövästä voi parantua kirurgisella hoidolla. Osa kohtusyövistä on kuitenkin lähettänyt etäpesäkkeitä ja pieni osa paikalliselta vaikuttavista taudeista uusii. Kirurgisen hoidon laajuus sekä mahdolliset liitännäishoidot räätälöidään potilaskohtaisen riskiarvion perusteella pyrkien välttämään haitallista yli- tai alihoitoa. Riskiarvio perustuu kuvantamistutkimuksiin ja histopatologiaan. Patologi määrittää kasvaimen kudostyypin ja muita taudin käyttäytymistä ennustavia tekijöitä. Tutkijoiden tavoitteena on löytää uusia kudostason merkkiaineita, jotka entisestään tarkentaisivat optimaalisen hoidon suunnittelua. Vuonna 2013 syöpägenomiprojektissa kehitettiin uusi, molekulaarinen tautiluokittelu, joka osoittaa tietä kohti yksilöllistettyä kohtusyövän hoitoa. Tutkimusaineisto koostui HUSin Naistenklinikalla vuosina 2007-2012 leikattujen kohtusyöpäpotilaiden kasvainnäytteistä ja kliinisistä tiedoista. Osatyössä II oli lisäksi käytettävissä myöhemmin kerättyjä kohtusyöpäpotilaiden veri- ja kudosnäytteitä. Tavoitteena oli tutkia taudin etenemistä ennustavia molekulaarisia merkkiaineita sekä immunologisen hoidon kannalta tärkeän kohdemolekyylin ilmentymistä eri kohtusyövän alatyypeissä. I: L1CAM-proteiinin esiintyminen kasvainsoluissa korreloi taudin levinneisyyden ja huonon ennusteen kanssa kohtusyövän yleisimmässä eli endometrioidissa alatyypissä, mutta ei harvinaisemmassa non-endometrioidissa alatyypissä. II: L1CAM-positiiviset kohtusyövät olivat levinneet imusolmukkeisiin useammin kuin L1CAM-negatiiviset kasvaimet, mutta L1CAM-löydöksen lisääminen perinteisiin riskimalleihin ei parantanut näiden kykyä ennustaa imusolmukelevinneisyyttä ennen potilaan leikkaushoitoa. III: kohtusyövän histopatologisten ja molekulaaristen alatyyppien välillä nähtiin eroavaisuuksia koskien sekä tulehdussolujen määrää että immunoterapian kohdemolekyylin PD-L1:n esiintyvyyttä. IV: metylaation aiheuttama DNA:n korjausmekanismin vaurio kasvainsoluissa huonontaa potilaan elinaikaodotetta. V: Kohtusyövän kahdessa suurimmassa molekulaarisessa alaryhmässä taudin aggressiivisuuteen liitetyillä riskitekijöillä oli erilainen ennusteellinen painoarvo. Yhteenvetona toteamme, että molekulaarinen tautiluokitus auttaa mahdollistamaan kohtusyövän yksilöllistetyn hoidon. Koska molekulaarisissa tautiluokissa syövän syntymekanismit ja taudin käyttäytyminen ovat hyvin erilaisia, kohtusyövän molekulaarisia alaryhmiä tulisi tarkastella erillisinä tautikokonaisuuksina. Täten yksittäiselle potilaalle saataisiin suunniteltua hoito, joka toimii parhaiten juuri kyseisessä tautityypissä

Molecular classification of endometrial carcinoma : a clinically oriented review

The Cancer Genome Atlas research network performed a genome-wide analysis of endometrial carcinomas in 2013 and classified tumours into four distinct subgroups: polymerase-epsilon ultramutated, microsatellite unstable hypermutated, copy-number low and copy-number high. These molecular alterations are mostly mutually exclusive as only about 3% of tumours exhibit more than one molecular signature. Apart from the polymerase-epsilon ultramutated subgroup, molecular classification can be reproduced by using surrogate markers. This has facilitated the implementation of molecular diagnostics into routine patient care. Molecular subgroups are associated with different prognoses; thus, improved risk assessment is their most obvious clinical application. However, based on their unique molecular architectures, molecular subgroups should not be regarded simply as risk groups but rather as distinct diseases. This has prompted us and others to examine the role of molecular subgroups in modifying the prognostic effect of traditional risk factors, including clinical factors, uterine factors and tissue biomarkers, and in predicting the response to adjuvant therapies. In the following review, we summarise the current knowledge of molecularly classified endometrial carcinoma and present, based on our own experience, a proposal for implementing molecular classification into daily practice in pathology laboratories.Peer reviewe

Mismatch repair protein and MLH1 methylation status as predictors of response to adjuvant therapy in endometrial cancer

Background: Mismatch repair (MMR) system has been implicated in the response of mammalian cells to ionizing radiation and DNA damaging agents. We investigated the value of the MMR system in predicting response to adjuvant therapy in endometrial cancer. Methods: This was a single institution retrospective study. MMR protein status of endometrial carcinomas was assessed by immunohistochemistry. MMR deficient (MMR-D) tumors were identified as MLH1 methylated or nonmethylated by methylation-specific multiplex ligation-dependent probe amplification. Tumors with abnormal p53 staining or polymerase epsilon exonuclease domain mutation were excluded from the MMR proficient subgroup, which was termed as "no specific molecular profile" (NSMP). Disease-specific survival analyses were adjusted for age, stage, histology and grade, depth of myometrial invasion, and lymphovascular space invasion. Results: A total of 505 patients were included in the study. Median follow-up time was 81 months (range 1-136). Whole pelvic radiotherapy (adjusted hazard ratio [HR] 0.092 vs. no adjuvant therapy) and chemotherapy combined with radiotherapy (adjusted HR 0.18) were associated with improved disease-specific survival in the NSMP subgroup (n = 218). In contrast, adjuvant therapies showed no effect on disease-specific survival in the full MMR-D cohort (n = 287) or in MLH1 methylated tumors (n = 154). Whole pelvic radiotherapy (adjusted HR 25 vs. no adjuvant therapy/vaginal brachytherapy) and chemotherapy combined with whole pelvic radiotherapy (adjusted HR 32) were associated with poor disease-specific survival in MMR-D nonmethylated tumors (n = 70). Conclusion: MMR protein and MLH1 methylation status predict the response to adjuvant therapy in endometrial cancer. The MMR system could be utilized for selection of patients who most likely benefit from adjuvant therapy.Peer reviewe

Mismatch Repair Deficiency as a Predictive and Prognostic Biomarker in Molecularly Classified Endometrial Carcinoma

The aggressiveness of mismatch repair (MMR) deficient endometrial carcinomas was examined in a single institution retrospective study. Outcomes were similar for MMR proficient (n = 508) and deficient (n = 287) carcinomas, identified by immunohistochemistry. In accordance with molecular classification based on The Cancer Genome Atlas (TCGA), tumors with abnormal p53 staining or polymerase-ϵ exonuclease domain mutation were excluded from the MMR proficient subgroup, termed as “no specific molecular profile” (NSMP). Compared with NSMP (n = 218), MMR deficiency (n = 191) was associated with poor disease-specific survival (p = 0.001). MMR deficiency was associated with an increased risk of cancer-related death when controlling for confounders (hazard ratio 2.0). In the absence of established clinicopathologic risk factors, MMR deficiency was invariably associated with an increased risk of cancer-related death in univariable analyses (hazard ratios ≥ 2.0). In contrast, outcomes for MMR deficient and NSMP subgroups did not differ when risk factors were present. Lymphatic dissemination was more common (p = 0.008) and the proportion of pelvic relapses was higher (p = 0.029) in the MMR deficient subgroup. Our findings emphasize the need for improved triage to adjuvant therapy and new therapeutic approaches in MMR deficient endometrial carcinomas

Clinicopathologic vs. Molecular Integrated Prognostication of Endometrial Carcinoma by European Guidelines

This was a retrospective study of 604 patients with endometrial carcinoma, classified into ESGO-ESTRO-ESP 2021 clinicopathologic and molecular integrated risk groups. The Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE) and Leiden classifier were employed for molecular classification. Median follow-up time was 81 months. Clinicopathologic and molecular integrated risk groups were similarly associated with distinct prognoses (p < 0.001). Disease-specific survival was similar for all molecular subgroups within clinicopathologic intermediate-risk, high-risk, and advanced/metastatic groups. In contrast, the p53 abnormal subgroup (hazard ratio 9.1, 95% confidence interval 2.0–41; p = 0.004) and mismatch repair deficient subgroup (hazard ratio 3.5, 95% confidence interval 1.2–10; p = 0.024) were associated with disease-related death within clinicopathologic low-risk and high-intermediate-risk carcinomas, respectively. A risk-group shift occurred in 6.0% (36/604) and 7.4% (38/515) of patients classified by ProMisE and Leiden, respectively (p = 0.341). Of the 36 patients shifted in the ProMisE cohort, 27 were upshifted and 9 downshifted. Based on the Leiden classifier, polymerase-ϵ sequencing could be omitted in 60% (311/515) of patients without affecting the risk-group assessment. ESGO-ESTRO-ESP 2021 guidelines provide a platform for risk classification in future trials on molecularly directed treatment of endometrial carcinoma

Clinicopathologic vs. Molecular Integrated Prognostication of Endometrial Carcinoma by European Guidelines

This was a retrospective study of 604 patients with endometrial carcinoma, classified into ESGO-ESTRO-ESP 2021 clinicopathologic and molecular integrated risk groups. The Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE) and Leiden classifier were employed for molecular classification. Median follow-up time was 81 months. Clinicopathologic and molecular integrated risk groups were similarly associated with distinct prognoses (p < 0.001). Disease-specific survival was similar for all molecular subgroups within clinicopathologic intermediate-risk, high-risk, and advanced/metastatic groups. In contrast, the p53 abnormal subgroup (hazard ratio 9.1, 95% confidence interval 2.0–41; p = 0.004) and mismatch repair deficient subgroup (hazard ratio 3.5, 95% confidence interval 1.2–10; p = 0.024) were associated with disease-related death within clinicopathologic low-risk and high-intermediate-risk carcinomas, respectively. A risk-group shift occurred in 6.0% (36/604) and 7.4% (38/515) of patients classified by ProMisE and Leiden, respectively (p = 0.341). Of the 36 patients shifted in the ProMisE cohort, 27 were upshifted and 9 downshifted. Based on the Leiden classifier, polymerase-ϵ sequencing could be omitted in 60% (311/515) of patients without affecting the risk-group assessment. ESGO-ESTRO-ESP 2021 guidelines provide a platform for risk classification in future trials on molecularly directed treatment of endometrial carcinoma

Mismatch Repair Deficiency as a Predictive and Prognostic Biomarker in Molecularly Classified Endometrial Carcinoma

The aggressiveness of mismatch repair (MMR) deficient endometrial carcinomas was examined in a single institution retrospective study. Outcomes were similar for MMR proficient (n = 508) and deficient (n = 287) carcinomas, identified by immunohistochemistry. In accordance with molecular classification based on The Cancer Genome Atlas (TCGA), tumors with abnormal p53 staining or polymerase-ϵ exonuclease domain mutation were excluded from the MMR proficient subgroup, termed as “no specific molecular profile” (NSMP). Compared with NSMP (n = 218), MMR deficiency (n = 191) was associated with poor disease-specific survival (p = 0.001). MMR deficiency was associated with an increased risk of cancer-related death when controlling for confounders (hazard ratio 2.0). In the absence of established clinicopathologic risk factors, MMR deficiency was invariably associated with an increased risk of cancer-related death in univariable analyses (hazard ratios ≥ 2.0). In contrast, outcomes for MMR deficient and NSMP subgroups did not differ when risk factors were present. Lymphatic dissemination was more common (p = 0.008) and the proportion of pelvic relapses was higher (p = 0.029) in the MMR deficient subgroup. Our findings emphasize the need for improved triage to adjuvant therapy and new therapeutic approaches in MMR deficient endometrial carcinomas

Preoperative Risk Stratification of Endometrial Carcinoma : L1CAM as a Biomarker

Objective Preoperative or intraoperative risk assessment models are used to stratify patients with endometrial carcinoma to lymphadenectomy. Our aim was to determine whether preoperative analysis of L1 cell adhesion molecule (L1CAM) can improve risk assessment. Methods Immunohistochemical L1CAM staining was performed on endometrial biopsies of 241 patients and paired hysterectomy samples of 75 patients. Risk assessment models based on preoperative histologic type and grade, myometrial invasion, and/or tumor diameter and alternative models incorporating preoperative L1CAM were compared with regard to their capability of predicting lymph nodal or distant metastasis. Soluble L1 levels were measured by enzyme-linked immunosorbent assay in serum samples of 40 patients with endometrial carcinoma. Results The concordance rate between L1CAM staining results of preoperative and hysterectomy samples was moderate ( = 0.586, P <0.0001). Preoperative L1CAM expression was associated with nonendometrioid histology, lymph node involvement, advanced stage, and positive peritoneal cytology. Receiver operating characteristic curve analyses showed that L1CAM did not significantly improve risk stratification algorithms based on traditional risk factors. Intraoperative tumor diameter was an effective surrogate for myometrial invasion. There was no statistical difference between L1 serum levels of patients with an L1CAM-positive or L1CAM-negative endometrial carcinoma (P = 0.786). Conclusions L1 cell adhesion molecule expression in endometrial biopsy correlates with high-risk features of endometrial carcinoma but does not significantly improve risk stratification algorithms based on traditional factors. Soluble L1 detected in the serum of patients with endometrial carcinoma does not correlate with tumoral L1CAM expression.Peer reviewe

Prediction of lymphatic dissemination in endometrioid endometrial cancer : Comparison of three risk-stratification models in a single-institution cohort

Objectives. To compare the performance characteristics of 3 risk-stratification models, referred to as Mayo, Helsinki and Milwaukee models, in predicting lymphatic dissemination in endometrial cancer. Methods. A total of 1052 patients with stage I-Ill endometrioid endometrial cancer were included in the study. The areas under curve were compared with the receiver operating characteristic curve area comparison test Chi-square and Fisher exact test were used for comparing categorical variables. The Kaplan-Meier method and multivariable Cox regression models were used for survival analyses. The median follow-up time was 55 months (range 1-108). Results. Areas under curve were 0.781, 0.830 and 0.829 for the Mayo, Helsinki (P = 0.285 vs. Mayo) and Milwaukee (P = 0.292 vs. Mayo) models, respectively, in predicting lymphatic dissemination. The rates of false negatives and false positives were similar for all models. The lymphadenectomy rate decreased in the order of Mayo model (71.5%) > Helsinki model (62.4%) > Milwaukee model (48.8%). In patients with stage I cancer, disease specific survival was better for those who satisfied low-risk criteria according to any of the models. In patients with stage II-III cancer, this difference in survival was significant only for the Milwaukee model, Both lymphatic dissemination and high-risk tumor features as per the risk models were independent predictors of survival. Conclusions. The studied models had a similar accuracy in predicting lymphatic dissemination in endometrial cancer. Lymphadenectomy rate was lowest for the Milwaukee model. Survival analyses suggest that variables included in the models predict patient outcome independently of tumor stage. (C) 2017 Elsevier Inc. All rights reserved.Peer reviewe