Characterisation of tumour microvessel density during progression of high-grade serous ovarian cancer: clinico-pathological impact (an OCTIPS Consortium study).

BACKGROUND: High-grade serous ovarian cancer (HGSOC) intratumoural vasculature evolution remains unknown. The study investigated changes in tumour microvessel density (MVD) in a large cohort of paired primary and recurrent HGSOC tissue samples and its impact on patients' clinico-pathological outcome. METHODS: A total of 222 primary (pOC) and recurrent (rOC) intra-patient paired HGSOC were assessed for immunohistochemical expression of angiogenesis-associated biomarkers (CD31, to evaluate MVD, and VEGF-A). Expression profiles were compared between pOCs and rOCs and correlated with patients' data. RESULTS: High intratumoural MVD and VEGF-A expression were observed in 75.7% (84/111) and 20.7% (23/111) pOCs, respectively. MVDhigh and VEGF(+) samples were detected in 51.4% (57/111) and 20.7% (23/111) rOCs, respectively. MVDhigh/VEGF(+) co-expression was found in 19.8% (22/111) and 8.1% (9/111) of pOCs and rOCs, respectively (p = 0.02). Pairwise analysis showed no significant change in MVD (p = 0.935) and VEGF-A (p = 0.121) levels from pOCs to rOCs. MVDhigh pOCs were associated with higher CD3(+) (p = 0.029) and CD8(+) (p = 0.013) intratumoural effector TILs, while VEGF(+) samples were most frequently encountered among BRCA-mutated tumours (p = 0.019). Multivariate analysis showed VEGF and MVD were not independent prognostic factors for OS. CONCLUSIONS: HGSOC intratumoural vasculature did not undergo significant changes during disease progression. High concentration of CD31(+) vessels seems to promote recruitment of effector TILs. The study also provides preliminary evidence of the correlation between VEGF-positivity and BRCA status.

Morphology and tumour-infiltrating lymphocytes in high-stage, high-grade serous ovarian carcinoma correlated with long-term survival.

AIMS: Advanced-stage ovarian high-grade serous carcinoma (HGSC) is a poor-prognosis cancer; however, a small and poorly characterised subset of patients shows long-term survival. We aimed to establish a cohort of HGSC long-term survivors for histopathological and molecular analysis. METHODS AND RESULTS: Paraffin blocks from 151 patients with primary FIGO III/IV HGSC and progression-free survival (PFS) >5 years were collected within the Tumorbank Ovarian Cancer (TOC) Network; 77 HGSC with a PFS <3 years were used as a control group. A standardised analysis of histological type and morphological features was performed. Ki67 index, tumour-infiltrating lymphocytes (TILs) and major histocompatibility complex expression (MHC1/2) were determined by immunohistochemistry. A total of 117 of 151 tumours (77.5%) in the long-term survivor group fulfilled the World Health Organisation (WHO) criteria of HGSC after review, and of these, 83 patients (70.9%) fulfilled all clinical criteria for inclusion into our cohort. Tumours of long-term survivors had significantly higher CD3+ and CD8+ TILs and were more frequently positive for MHC2 than controls (P = 0.004, P = 0.025, P = 0.048). However, there were also long-term survivors (up to 20%) with low TILs or low MHC expression. TILs and MHC had no impact on survival in long-term survivors. Morphological and Ki67 analysis revealed no differences between long-term survivors and controls. CONCLUSIONS: HGSC from long-term survivors have higher-level T cell infiltration and antigen-presentation capacity; however, this is not a prerequisite for an excellent prognosis. Histopathological criteria are not capable to identify these patients. Further extensive clinical and molecular characterisation of this enigmatic subgroup is ongoing to understand the reasons of long-term survival in HGSC.

Vascular endothelial growth factor receptor 2 (VEGFR2) correlates with long-term survival in patients with advanced high-grade serous ovarian cancer (HGSOC): a study from the Tumor Bank Ovarian Cancer (TOC) Consortium.

OBJECTIVE: The impact of angiogenesis on long-term survival of high-grade serous ovarian cancer (HGSOC) patients remains unclear. This study investigated whether angiogenic markers correlated with 5-year progression-free survival (PFS) in a large cohort of matched advanced HGSOC tissue samples. METHODS: Tumor samples from 124 primary HGSOC patients were retrospectively collected within the Tumor Bank Ovarian Cancer ( http://www.toc-network.de ). All patients were in advanced stages (FIGO stage III-IV). No patient had received anti-angiogenesis therapy. The cohort contains 62 long-term survivors and 62 controls matched by age and post-surgical tumor residuals. Long-term survivors were defined as patients with no relapse within 5 years after the end of first-line chemotherapy. Controls were patients who suffered from first relapse within 6-36 months after primary treatment. Samples were assessed for immunohistochemical expression of vascular endothelial growth factor (VEGF) A and VEGF receptor 2 (VEGFR2). Expression profiles of VEGFA and VEGFR2 were compared between the two groups. RESULTS: Significant correlation between VEGFA and VEGFR2 expression was observed (p < 0.0001, Spearman coefficient 0.347). A high expression of VEGFR2 (VEGFR2high) was found more frequently in long-term survivors (77.4%, 48/62) than in controls (51.6%, 30/62, p = 0.001), independent of FIGO stage and VEGFA expression in multivariate analysis (p = 0.005). Also, VEGFR2high was found the most frequently in women with PFS ≥ 10 years (p = 0.001) among all 124 patients. However, no significant association was detected between VEGFA expression and 5-year PFS (p = 0.075). CONCLUSIONS: VEGFR2 overexpression significantly correlated with long-term PFS in HGSOC patients, independent of age, FIGO stage, tumor residual and VEGFA expression.

Dynamics of the Intratumoral Immune Response during Progression of High-Grade Serous Ovarian Cancer.

PURPOSE: Tumor-infiltrating lymphocytes (TILs) have an established impact on the prognosis of high-grade serous ovarian carcinoma (HGSOC), however, their role in recurrent ovarian cancer is largely unknown. We therefore systematically investigated TIL densities and MHC class I and II (MHC1, 2) expression in the progression of HGSOC. EXPERIMENTAL DESIGN: CD3+, CD4+, CD8+ TILs and MHC1, 2 expression were evaluated by immunohistochemistry on tissue microarrays in 113 paired primary and recurrent HGSOC. TILs were quantified by image analysis. All patients had been included to the EU-funded OCTIPS FP7 project. RESULTS: CD3+, CD4+, CD8+ TILs and MHC1 and MHC2 expression showed significant correlations between primary and recurrent tumor levels (Spearman rho 0.427, 0.533, 0.361, 0.456, 0.526 respectively; P<.0001 each). Paired testing revealed higher CD4+ densities and MHC1 expression in recurrent tumors (Wilcoxon P=.034 and P=.018). There was also a shift towards higher CD3+ TILs levels in recurrent carcinomas when analyzing platinum-sensitive tumors only (Wilcoxon P=.026) and in pairs with recurrent tumor tissue from first relapse only (Wilcoxon P=.031). High MHC2 expression was the only parameter to be significantly linked to prolonged progression-free survival after first relapse (PFS2, log-rank P=.012). CONCLUSIONS: This is the first study that analyzed the development of TILs density and MHC expression in paired primary and recurrent HGSOC. The level of the antitumoral immune response in recurrent tumors was clearly dependent on the one in the primary tumor. Our data contribute to the understanding of temporal heterogeneity of HGSOC immune microenvironment and have implications for selection of samples for biomarker testing in the setting of immune-targeting therapeutics.

Exploring the clonal evolution of CD133/aldehyde-dehydrogenase-1 (ALDH1)-positive cancer stem-like cells from primary to recurrent high-grade serous ovarian cancer (HGSOC). A study of the Ovarian Cancer Therapy-Innovative Models Prolong Survival (OCTIPS) Consortium.

BACKGROUND: High-grade serous ovarian cancer (HGSOC) causes 80% of all ovarian cancer (OC) deaths. In this setting, the role of cancer stem-like cells (CSCs) is still unclear. In particular, the evolution of CSC biomarkers from primary (pOC) to recurrent (rOC) HGSOCs is unknown. Aim of this study was to investigate changes in CD133 and aldehyde dehydrogenase-1 (ALDH1) CSC biomarker expression in pOC and rOC HGSOCs. METHODS: Two-hundred and twenty-four pOC and rOC intrapatient paired tissue samples derived from 112 HGSOC patients were evaluated for CD133 and ALDH1 expression using immunohistochemistry (IHC); pOCs and rOCs were compared for CD133 and/or ALDH1 levels. Expression profiles were also correlated with patients' clinicopathological and survival data. RESULTS: Some 49.1% of the patient population (55/112) and 37.5% (42/112) pOCs were CD133+ and ALDH1+ respectively. CD133+ and ALDH1+ samples were detected in 33.9% (38/112) and 36.6% (41/112) rOCs. CD133/ALDH1 coexpression was observed in 23.2% (26/112) and 15.2% (17/112) of pOCs and rOCs respectively. Pairwise analysis showed a significant shift of CD133 staining from higher (pOCs) to lower expression levels (rOCs) (p < 0.0001). Furthermore, all CD133 + pOC patients were International Federation of Gynaecology and Obstetrics (FIGO)-stage III/IV (p < 0.0001) and had significantly worse progression-free interval (PFI) (p = 0.04) and overall survival (OS) (p = 0.02). On multivariate analysis, CD133/ALDH1 coexpression in pOCs was identified as independent prognostic factor for PFI (HR: 1.64; 95% CI: 1.03-2.60; p = 0.036) and OS (HR: 1.71; 95% CI: 1.01-2.88; p = 0.045). Analysis on 52 pts patients with known somatic BRCA status revealed that BRCA mutations did not influence CSC biomarker expression. CONCLUSIONS: The study showed that CD133/ALDH1 expression impacts HGSOC patients' survival and first suggests that CSCs might undergo phenotypic change during the disease course similarly to non stem-like cancer cells, providing also a first evidence that there is no correlation between CSCs and BRCA status.