Synergy of the microRNA Ratio as a Promising Diagnosis Biomarker for Mucinous Borderline and Malignant Ovarian Tumors

Epithelial ovarian cancers (EOCs) are a heterogeneous collection of malignancies, each with their own developmental origin, clinical behavior and molecular profile. With less than 5% of EOC cases, mucinous ovarian carcinoma is a rare form with a poor prognosis and a 5-year survival of 11% for advanced stages (III/IV). At the early stages, these malignant forms are clinically difficult to distinguish from borderline (15%) and benign (80%) forms with a better prognosis due to the large size and heterogeneity of mucinous tumors. Improving their diagnosis is therefore a challenge with regard to the risk of under-treating a malignant form or of unnecessarily undertaking radical surgical excision. The involvement of microRNAs (miRNAs) in tumor progression and their potential as biomarkers of diagnosis are becoming increasingly recognized. In this study, the comparison of miRNA microarray expression profiles between malignant and borderline tumor FFPE samples identified 10 down-regulated and 5 up-regulated malignant miRNAs, which were validated by individual RT-qPCR. To overcome normalization issues and to improve the accuracy of the results, a ratio analysis combining paired up-regulated and down-regulated miRNAs was performed. Although 21/50 miRNA expression ratios were significantly different between malignant and borderline tumor samples, any ratio could perfectly discriminate the two groups. However, a combination of 14 pairs of miRNA ratios (double ratio) showed high discriminatory potential, with 100% of accuracy in distinguishing malignant and borderline ovarian tumors, which suggests that miRNAs may hold significant clinical potential as a diagnostic tool. In summary, these ratio miRNA-based signatures may help to improve the precision of histological diagnosis, likely to provide a preoperative diagnosis in order to adapt surgical procedures.

Comparative analysis of response to treatments and molecular features of tumor-derived organoids versus cell lines and PDX derived from the same ovarian clear cell carcinoma

BACKGROUND

In the era of personalized medicine, the establishment of preclinical models of cancer that faithfully recapitulate original tumors is essential to potentially guide clinical decisions.

METHODS

We established 7 models [4 cell lines, 2 Patient-Derived Tumor Organoids (PDTO) and 1 Patient-Derived Xenograft (PDX)], all derived from the same Ovarian Clear Cell Carcinoma (OCCC). To determine the relevance of each of these models, comprehensive characterization was performed based on morphological, histological, and transcriptomic analyses as well as on the evaluation of their response to the treatments received by the patient. These results were compared to the clinical data.

RESULTS

Only the PDX and PDTO models derived from the patient tumor were able to recapitulate the patient tumor heterogeneity. The patient was refractory to carboplatin, doxorubicin and gemcitabine, while tumor cell lines were sensitive to these treatments. In contrast, PDX and PDTO models displayed resistance to the 3 drugs. The transcriptomic analysis was consistent with these results since the models recapitulating faithfully the clinical response grouped together away from the other classical 2D cell culture models. We next investigated the potential of drugs that have not been used in the patient clinical management and we identified the HDAC inhibitor belinostat as a potential effective treatment based on PDTO response.

CONCLUSIONS

PDX and PDTO appear to be the most relevant models, but only PDTO seem to present all the necessary prerequisites for predictive purposes and could constitute relevant tools for therapeutic decision support in the context of these particularly aggressive cancers refractory to conventional treatments.

Recommandations pour la pratique clinique Nice/Saint-Paul-de-Vence 2022–2023 : Diagnostic histomoléculaire des carcinomes de l'endomètre

French recommendations for clinical practice Nice-Saint-Paul de Vence 2022-2023: histomolecular diagnosis of endometrial carcinomas The characterisation of endometrial carcinomas has been recently modified and enriched by molecular classification, the integration of which now impacts therapeutic decisions on whether adjuvant therapy should be administered or not in localized tumors, and influences treatment selection in advanced disease. Mandatory information includes histological type according to WHO 2020 classification, histological grade, hormone receptors status and molecular classification, the main new elements to provide being analysis of MMR proteins, p53 status and POLE status in selected cases. Sampling and preparation of material must be performed adequately to allow complete analysis. Numerous markers can be used to better define histological type, distinguish between primary lesion or metastases, or provide prognostic information. Determination of MMR/MSI profile is complex but well defined by guidelines that precisely describe techniques to be used and interpretation rules. Knowledge of POLE status is useful to guide therapeutic strategy, especially to consider de-escalation in stages I and II, in particular in case of high grade and/or p53 mutated tumors. This is why indications of POLE determination must be well defined. Finally, oncogenetics consultation is recommended in dMMR tumors (except in case or MLH1 promoter methylation) and in patients with evocative familial history.

ORGAVADS: establishment of tumor organoids from head and neck squamous cell carcinoma to assess their response to innovative therapies

BACKGROUND

Radiotherapy is one of the cornerstones of the treatment of Head and Neck Squamous Cell Carcinomas (HNSCC). However, radioresistance is associated with a high risk of recurrence. To propose strategies (such as combinations with drugs) that could over intrinsic radioresistance, it is crucial to predict the response to treatment. Patient-Derived Tumor Organoids (PDTO) are in vitro tridimensional microtumors obtained from patient' own cancer samples. They have been shown to serve as reliable surrogates of the tumor response in patients.

METHODS

The ORGAVADS study is a multicenter observational trial conducted to investigate the feasibility of generating and testing PDTO derived from HNSCC for the evaluation of sensitivity to treatments. PDTO are obtained after dissociation of resected tumors remaining from tissues necessary for the diagnosis. Embedding of tumor cells is then performed in extracellular matrix and culture in medium supplemented with growth factors and inhibitors. Histological and immunohistochemical characterizations are performed to validate the resemblance between PDTO and their original tumor. Response of PDTO to chemotherapy, radiotherapy and innovating combinations are assessed, as well as response to immunotherapy using co-cultures of PDTO with autologous immune cells collected from patient blood samples. Transcriptomic and genetic analyses of PDTO allow validation of the models compared to patients' own tumor and identification of potential predictive biomarkers.

DISCUSSION

This study is designed to develop PDTO models from HNSCC. It will allow comparing the response of PDTO to treatment and the clinical response of the patients from whom they are derived. Our aim is to study the PDTO ability to predict the clinical response to treatment for each patient in view of a personalized medicine as well as to establish a collection of HNSCC models that will be useful for future innovative strategies evaluation.

TRIAL REGISTRATION

NCT04261192, registered February 7, 2020, last amendment v4 accepted on June, 2021.

Postoperative radiotherapy after flap reconstructive surgery in patients with head and neck cancer: A retrospective monocentric study with flap delineation to assess toxicity and relapse

PURPOSE

Flaps are increasingly used during reconstructive surgery of head and neck cancers to improve functional outcomes. There are no guidelines as to whether the whole flap or its anastomotic border should be included in the primary tumour target volume of postoperative radiotherapy to prevent local relapses. Relapse and toxicity rates can increase substantially if the whole flap received full dose. Our aim was to determine whether flaps were included in the primary tumour target volume and to report the patterns of relapse and toxicity.

MATERIALS AND METHODS

Consecutive patients in 2014 through 2016, with or without a flap, receiving postoperative radiotherapy were selected in a retrospective monocentric control study. Flaps were homogenously delineated blind to treating radiation oncologists using a flap-specific atlas. Tumour recurrence, acute and late toxicity were evaluated using univariate and propensity score analyses.

RESULTS

A hundred patients were included; 54 with a flap. Median flap volume included in the tumour volume was 80.9%. Twelve patients experienced local recurrences: six with a flap, among whom two within their flap (3.7%). Patients with flaps had larger median tumour volumes to be irradiated (25cm³ versus 58cm³, p<0.001) and higher acute/late toxicity rates (p<0.001) even after adjustment on biases (more advanced T stage, oral cavity, active smoking in patients with flaps). Locoregional recurrence and survival rates were similar between patients with/without a flap.

CONCLUSION

Recurrences within a flap were rare in this series when including the whole flap body in the 60Gy-clinical target volume but inclusion of the flap in the primary tumour target volume increased toxicity. Multicentric studies are warranted.

Multicentre randomized phase II trial of olaparib as maintenance therapy in platinum-sensitive advanced endometrial carcinoma: The GINECO-UTOLA study

TPS6109

Background: Advanced endometrial cancer (EC) patients relapse despite treatment with combination chemotherapy and have a short progression-free survival (PFS). Data from the TGCA suggest opportunities to targeting DNA repair in women with EC. Particularly type 4 (High copy number or serous like, with frequent TP53 mutations) and type 2 (microsatellite instability hypermutated) EC can be associated with defects in double strand break DNA repair by homologous recombination (HR) and could potentially be targeted by olaparib. We propose a placebo-controlled, multicenter, two-arm, phase II trial comparing olaparib versus placebo in maintenance therapy after chemotherapy in patients with advanced/metastatic EC. Methods: The primary objective of this trial is to evaluate the efficacy of maintenance olaparib in comparison to placebo after platinum based chemotherapy, defined by PFS according to Recist. Key eligibility criteria include: advanced/metastatic histologically confirmed EC (excepted carcino-sarcoma, small cells& neuroendocrine); prior surgery, adjuvant chemotherapy, radiation and hormonal therapy are permitted; objective or stable response after first-line chemotherapy is mandatory. 147 patients are randomized (2:1) after chemotherapy to receive Olaparib 300mg twice daily or placebo in maintenance after at least 4 cycles of platinum based chemotherapy. Olaparib/placebo is continued until disease progression, unacceptable toxicity, or withdrawal. Stratification is on IHC P53 and MMR status. Primary hypothesis is a 66.7% relative increase in the median PFS rate in the olaparib arm (from 4.5 to 7.5 months), corresponding to a 0.60 Hazard Ratio. Secondary endpoints include PFS according to P53, MMR and NGS HRD status, PFS2, disease specific survival, time to subsequent therapy, overall survival, objective response, disease control rate, patient reported outcomes (assessed via EORTC QLQ-C30 and EORTC QLQ-EN24, EORTC-FA, EQ5D) and safety. Trial is recruiting in France (in February n= 40 randomization). Conclusion: this will be the first study that evaluate the efficacy of olaparib in maintenace after chemotherapy in advanced/metastastic EC, stratified on molecular profil. Clinical trial information: NCT03745950.

Tumoral genetic variations of the homologous recombination (HR) reparation system in brain metastases in women with epithelial ovarian cancer (EOC)

e17048

Background: Brain metastases (BM) EOC are rare and late events. We explored tumoral genetic variations of HR system. We identify genomic alterations with NGS in both primary tumor and BM EOC Methods: Seven patients suffering from histologically proven EOC and BM, which underwent neurosurgery, were included in the study. Seven matched samples (primary tumor and BM) were analyzed by high throughput sequencing after enrichment by capture of the whole exome. After bioinformatics procedures (BWA, HaplotypeCaller, Varscan2, Outlyzer) the analysis was restricted firstly to a in silico panel of 69 genes involved in HR system. Results: Mean age was 56 years (47 to 71). Five had serous and 2 endometrioid carcinomas. All the patients had an initial FIGO stage ≥IIIA, were platine-sensitive. Median time from diagnosis of EOC to BM was 29 months (24 to 76). BM occurred after first line treatment in 5 cases and after at least 2 relapses in the 2 other cases. Median Overall survival (OS) from diagnosis of BM was 17 months (1 to 45). Five primary tumor showed a variation of at least one HR gene: pathogenic variants inactivating in BRCA2 (n = 2), CDK12 (n = 1) and probably pathogenic missenses in BRIP1 (n = 1) and TOPB1 (n = 1). These 5 variations have been also found in the BM tissues. Among the 2 patients without variations in the primary tumor, 2 probably pathogenic missenses were detected in the BM tumor (1 FANCD2 and 1 FANCM). Time to BM relapse and OS were longer among these 2 last patients compared to the remaining 5 patients (median 68 vs 29 months and 90 vs 56 months, respectively). Conclusions: Patients with BM presented HR somatic mutations and are susceptible to have high response to Parp inhibitors.

[Primitive renal neuroectodermal tumor (PNET). Apropos of a case]

Renal primary neuroectodermal tumours (PNET) are exceptional and belong to the vast group of peripheral malignant primary neuroectodermal tumours (MPNT), the best known forms of which are Ewing's sarcoma of bone and Askin's thoracopulmonary tumour. In the light of a case, the authors discuss the clinical features, course, treatment and pathological characteristics, particularly the value of immunohistochemistry and cytogenetics, which demonstrate a specific chromosomal abnormality, the t (11;22) (q24;q12) translocation.