Yoann Lherm

Bio: Yoann Lherm is an academic researcher. The author has contributed to research in topics: Survival rate & Mesothelioma. The author has an hindex of 2, co-authored 3 publications receiving 21 citations.

Immunohistochemical evaluation of two antibodies against PD-L1 and prognostic significance of PD-L1 expression in epithelioid peritoneal malignant mesothelioma: A RENAPE study.

Abstract: Background Epithelioid peritoneal malignant mesothelioma (EPMM) is the most common subtype of this aggressive tumor. We compared two antibodies against PD-L1, a recent theranostic biomarker, and evaluated the prognostic value of PD-L1 expression by mesothelial and immune cells in EPMM. Methods Immunohistochemistry was performed on 45 EPMM. Clinical and pathological data were extracted from the RENAPE database. Using E1L3N and SP142 clones, inter-observer agreement, PD-L1 expression by mesothelial and immune cells and inter-antibody agreement were evaluated. The prognostic relevance of PD-L1 expression was evaluated in 39 EPMM by univariate and multivariate analysis of overall survival (OS) and progression-free survival (PFS). Results Inter-observer agreement on E1L3N immunostaining was moderate for mesothelial and immune cells, and fair for mesothelial and poor for immune cells using SP142. Using E1L3N, 31.1% of mesothelial and 15.6% of immune cells expressed PD-L1, and 22.2% of mesothelial and 26.7% of immune cells using SP142. Inter-antibody agreement was moderate. In most positive cases, 1–5% of tumor cells were positive. Using E1L3N, PD-L1 expression by lymphocytes was associated with better OS and PFS by both univariate and multivariate analysis. Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy predicted better prognosis than other treatments. Solid subtype was an independent prognostic factor for worse OS. Conclusion E1L3N appeared easier to use than SP142 to evaluate PD-L1 expression. A minority of EPMM expressed PD-L1, and only a few cells were positive. PD-L1 expression by immune cells evaluated with E1L3N was an independent prognostic factor in EPMM.

Well-Differentiated Papillary Mesothelioma of the Peritoneum: A Retrospective Study from the RENAPE Observational Registry

Abstract: Well-differentiated papillary mesothelioma of the peritoneum (WDPMP) is a rare entity. Questions regarding management are still being debated as no more than 50 cases have been reported in the literature. We aimed to analyze the clinical, therapeutic, and prognostic data of patients with WDPMP from the RENAPE observational registry. All patients diagnosed with WDPMP and prospectively included in the RENAPE national registry between 2010 and 2018 were also included in our study. Expert pathologists from the RENA-PATH group confirmed all cases. All clinical, therapeutic, postoperative, and prognostic data were extracted and analyzed. We report on 56 patients with a mean age of 52 years (range 21–74). WDPMP was incidentally diagnosed during imaging or surgery in 16% and 36% of patients, respectively, and an association with synchronous malignancy was found in 18% of patients. Nine lesions showed discrete signs of fatty invasion. The median Peritoneal Cancer Index was 11 (range 0–33). Eleven patients were treated with definitive excision, 4 were treated with cytoreductive surgery (CRS) only, 37 were treated with CRS and hyperthermic intraperitoneal chemotherapy (HIPEC), and 2 were treated with CRS plus HIPEC plus early postoperative intraperitoneal chemotherapy. CRS was considered to be complete in 90% of cases. One patient died postoperatively and 16 patients (31%) faced postoperative complications. The median disease-free survival was 144 months; Four patients relapsed, with a median period of 27 months. No prognostic factors could be identified. Our analysis confirms the favorable prognosis of WDPMP. CRS and HIPEC could be a therapeutic option for diffuse, symptomatic, and/or recurrent disease.

Ovarian and peritoneal psammocarcinoma: Results of a multicenter study on 25 patients.

Abstract: Purpose Psammocarcinoma (PK) is a rare disease of unknown origin. We aimed to report the characteristics, management and survival of patients operated on for PK within the French Network for Rare Peritoneal Malignancies (RENAPE) expert centers. Patients and methods All consecutive cases of PK operated within all 26 RENAPE centers between 1997 and 2018 were retrospectively analyzed. Results Twenty-five patients were identified. The median age was 53 years [range 17–78]. None of the patients had extra peritoneal metastases at diagnosis. A median of 6 cycles of carboplatin-based systemic chemotherapy was delivered in 52% preoperatively (n = 13) and 56% postoperatively (n = 14); associated with placlitaxel for 12 patients. All patients were operated on. The median PCI was 23 [0–33]. Eighty-four percent had a complete cytoreductive surgery through digestive (n = 7), spleen (n = 3), pancreas (n = 1) resections and/or multiple peritonectomies (n = 11). Five patients (20%) had intraperitoneal chemotherapy. Morbidity (Dindo-Clavien ≥3) was 12%. No postoperative death occurred. After a median follow-up of 42 months (range [2–194]), the median overall (OS) and progression-free (DFS) survival times were respectively 128 months and 31 months. Eighteen patients recurred (72%), mainly in the peritoneum (n = 16). Four of them (22%) were reoperated. The 5 and 10-year DFS rates were both 20.3%. The 5 and 10-year OS rates were 62% and 51.7%, respectively. A complete cytoreductive surgery was associated with a better OS and DFS in a univariate analysis. Conclusion Complete cytoreductive surgery is the cornerstone of the PK's management as a primary treatment. Recurrence remains common and new adjuvant strategies seem needed.

Peritoneal mesothelioma: PSOGI/EURACAN clinical practice guidelines for diagnosis, treatment and follow-up.

Abstract: Peritoneal mesothelioma (PM) is a rare and aggressive primary peritoneal malignancy characterized by widespread multiple metastatic tumour nodules originating from the peritoneum. The conventional classification distinguishes diffuse malignant peritoneal mesothelioma (DMPM) and border-line forms: multicystic peritoneal mesothelioma (MCPM) and well-differentiated papillary peritoneal mesothelioma (WDPPM). Despite the novel achievements in the management of PM, there is difficulty in conducting randomized trials due to its rarity and aggressive biology in many cases. As there is, a necessity to standardize diagnosis and management of PM, the Peritoneal Surface Oncology Group International (PSOGI) commissioned a steering committee to elaborate clinical guidelines.

Adenomatoid Tumor: A Review of Pathology With Focus on Unusual Presentations and Sites, Histogenesis, Differential Diagnosis, and Molecular and Clinical Aspects With a Historic Overview of Its Description.

Abstract: Adenomatoid tumors have been described almost a century ago, and their nature has been the subject of debate for decades. They are tumors of mesothelial origin usually involving the uterus, the Fallopian tubes, and the paratesticular region. Adenomatoid tumors of the adrenal gland, the liver, the extragenital peritoneum, the pleura, and the mediastinum have been rarely reported. They are usually small incidental findings, but large, multicystic and papillary tumors, as well as multiple tumors have been described. Their pathogenesis is related to immunosuppression and to TRAF7 mutations. Despite being benign tumors, there are several macroscopic or clinical aspects that could raise diagnostic difficulties. The aim of this review was to describe the microscopic and macroscopic aspects of adenomatoid tumor with a special focus on its differential diagnosis and pathogenesis and the possible link of adenomatoid tumor with other mesothelial lesions, such as the well-differentiated papillary mesothelioma and the benign multicystic mesothelioma, also known as multilocular peritoneal cysts.