Uncovering the WWTR1::NCOA2 Gene fusion in low-grade myoepithelial-rich neoplasm with HMGA2 expression: A case report.

We describe a case of a pleomorphic adenoma (PA) arising from the para-tracheal accessory salivary gland in a 44-year-old male harboring a novel WWTR1::NCOA2 gene fusion. To our knowledge, this novel gene fusion has not been described previously in salivary gland tumors. The patient presented with hoarseness of voice. The radiological exam revealed a mass in the upper third of the trachea involving the larynx. Histologically, the tumor consisted of bland-looking monocellular eosinophilic epithelial cells arranged in cords and sheets separated by thin fibrous stroma, focally forming a pseudo-tubular pattern. In immunohistochemistry, the tumor cells demonstrated positivity for CK7, PS100, SOX10, and HMGA2; and negativity for CK5/6, p40 p63, and PLAG1. In addition, the clustering analysis clearly demonstrates a clustering of tumors within the PA group. In addition to reporting this novel fusion in the PA spectrum, we discuss the relevant differential diagnoses and briefly review of NCOA2 and WWTR1 gene functions in normal and neoplastic contexts.

SOX10-Internal Tandem Duplications and PLAG1 or HMGA2 Fusions Segregate Eccrine-Type and Apocrine-Type Cutaneous Mixed Tumors.

Cutaneous mixed tumors exhibit a wide morphologic diversity and are currently classified into apocrine and eccrine types based on their morphologic differentiation. Some cases of apocrine-type cutaneous mixed tumors (ACMT), namely, hyaline cell-rich apocrine cutaneous mixed tumors (HCR-ACMT) show a prominent or exclusive plasmacytoid myoepithelial component. Although recurrent fusions of PLAG1 have been observed in ACMT, the oncogenic driver of eccrine-type cutaneous mixed tumors (ECMT) is still unknown. The aim of the study was to provide a comprehensive morphologic, immunohistochemical, and molecular characterization of these tumors. Forty-one cases were included in this study: 28 cases of ACMT/HCR-ACMT and 13 cases of ECMT. After morphologic and immunohistochemical characterization, all specimens were analyzed by RNA sequencing. By immunohistochemistry, all cases showed expression of SOX10, but only ACMT/HCR-ACMT showed expression of PLAG1 and HMGA2. RNA sequencing confirmed the presence of recurrent fusion of PLAG1 or HMGA2 in all cases of ACMT/HCR-ACMT, with a perfect correlation with PLAG1/HMGA2 immunohistochemical status, and revealed internal tandem duplications of SOX10 (SOX10-ITD) in all cases of ECMT. Although TRPS1::PLAG1 was the most frequent fusion, HMGA2::WIF1 and HMGA2::NFIB were detected in ACMT cases. Clustering analysis based on gene expression profiling of 110 tumors, including numerous histotypes, showed that ECMT formed a distinct group compared with all other tumors. ACMT, HCR-ACMT, and salivary gland pleomorphic adenoma clustered together, whereas myoepithelioma with fusions of EWSR1, FUS, PBX1, PBX3, POU5F1, and KLF17 formed another cluster. Follow-up showed no evidence of disease in 23 cases across all 3 tumor types. In conclusion, our study demonstrated for the first time SOX10-ITD in ECMT and HMGA2 fusions in ACMT and further refined the prevalence of PLAG1 fusions in ACMT. Clustering analyses revealed the transcriptomic distance between these different tumors, especially in the heterogenous group of myoepitheliomas.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy to Treat Pseudomyxoma Peritonei of Ovarian Origin: A Retrospective French RENAPE Group Study.

BACKGROUND: Ovarian pseudomyxoma peritonei (OPMP) are rare, without well-defined therapeutic guidelines. We aimed to evaluate cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) to treat OPMP. METHODS: Patients from the French National Network for Rare Peritoneal Tumors (RENAPE) database with proven OPMP treated by CRS/HIPEC and with histologically normal appendix and digestive endoscopy were retrospectively included. Clinical and follow-up data were collected. Histopathological and immunohistochemical features were reviewed. RESULTS: Fifteen patients with a median age of 56 years were included. The median Peritoneal Cancer Index was 16. Following CRS, the completeness of cytoreduction (CC) score was CC-0 for 9/15 (60%) patients, CC-1 for 5/15 (33.3%) patients, and CC-2 for 1/15 (6.7%) patients. The median tumor size was 22.5 cm. After pathological review and immunohistochemical studies, tumors were classified as Group 1 (mucinous ovarian epithelial neoplasms) in 3/15 (20%) patients; Group 2 (mucinous neoplasm in ovarian teratoma) in 4/15 (26.7%) patients; Group 3 (mucinous neoplasm probably arising in ovarian teratoma) in 5/15 (33.3%) patients; and Group 4 (non-specific group) in 3/15 (20%) patients. Peritoneal lesions were OPMP pM1a/acellular, pM1b/grade 1 (hypocellular) and pM1b/grade 3 (signet-ring cells) in 13/15 (86.7%), 1/15 (6.7%) and 1/15 (6.7%) patients, respectively. Disease-free survival analysis showed a difference (p = 0.0463) between OPMP with teratoma/likely-teratoma origin (groups 2 and 3; 100% at 1, 5, and 10 years), and other groups (groups 1 and 4; 100%, 66.6%, and 50% at 1, 5, and 10 years, respectively). CONCLUSION: These results suggested that a primary therapeutic strategy using complete CRS/HIPEC for patients with OPMP led to favorable long-term outcomes.

Peculiar nuclear atypia associated with MDM2 gene amplification in carcinoma ex-pleomorphic adenoma harbouring an alteration of HMGA2.

AIMS: Salivary gland neoplasms (SGN) exhibiting the HMGA2::WIF1 fusion are recognized by their resemblance to histology found in canalicular adenoma. Recently, ~20% of cases among 28 HMGA2::WIF1-rearranged-SGN showed malignancy and adverse outcomes (recurrence, distant metastasis, and disease-specific mortality). Among them, MDM2/CDK4 amplifications were identified in one case. This outcome suggests that the MDM2/CDK4 amplifications could be useful to predict an aggressive course of carcinoma ex-pleomorphic adenoma (CEPA). METHODS AND RESULTS: We investigated the correlation between HMGA2 fusion and MDM2 amplification in four salivary gland neoplasms, providing detailed clinicopathological features and outcomes. Cases were selected from different institutions. Histological examination, immunohistochemistry, fluorescence in situ hybridization (FISH), RNA sequencing, and whole-exome capture were performed. The cohort included four CEPA cases, all female, aged between 32 and 89 years. Tumours arose from the parotid gland with an average size of 24.5 mm. None exhibited recurrence or distant metastases during the 4-5 months of follow-up. Pathologically, all cases displayed a peculiar atypical nuclei with 'gear-like appearance'. Immunohistochemically, tumours exhibited a biphasic pattern with myoepithelial and ductal differentiation markers. All cases showed HMGA2 overexpression and MDM2 amplification by FISH and RNA sequencing. In a control cohort of MDM2 nonamplified CEPA cases, not exhibiting the peculiar nuclear atypia. CONCLUSIONS: Our findings suggest a strong correlation between HMGA2 alteration/MDM2 amplification and a peculiar nuclear atypia, advocating for their evaluation in biphasic tumours to facilitate accurate diagnosis and tailored posttumour removal monitoring. Further studies are warranted to validate these observations and elucidate their prognostic implications.

[Fusion genes in salivary gland tumors]. / Les tumeurs des glandes salivaires associées à des transcrits de fusion.

Salivary gland tumors represent a diagnostic challenge for pathologists due to their rarity, their very wide histopathological and immuno-phenotypic spectrum, and the recent identification of new entities. This article presents the main molecular characteristics of these tumors in order to allow any pathologist to perceive the diagnostic tracks of these ENT tumors and to better guide the molecular approach to establish the diagnosis and guide therapy.

Comparison of Neoadjuvant Systemic Chemotherapy Protocols for the Curative-Intent Management of Peritoneal Metastases from Colorectal Cancer, Regarding Morphological Response, Pathological Response, and Long-Term Outcomes: A Retrospective Study.

BACKGROUND: Selected patients with colorectal cancer peritoneal metastases (CRPM) could be offered a curative-intent strategy based on complete cytoreductive surgery (CRS), potentially combined with hyperthermic intraperitoneal chemotherapy (HIPEC) and perioperative systemic chemotherapy. The impact of different neoadjuvant systemic chemotherapy (NACT) regimens remains unclear due to a lack of comparative data. METHODS: Consecutive CRPM patients from a monocentric database who were treated with complete CRS after single-line NACT were included in this study. Chemotherapy regimens were tailored as a doublet drug (FOLFOX/FOLFIRI) with/without targeted therapy (anti-epidermal growth factor receptor/bevacizumab) and triplet-drug combination (FOLFIRINOX). Morphological response (MR) was assessed using the Response Evaluation Criteria in Solid Tumors criteria, and pathological response (PR) was assessed using the Peritoneal Regression Grading Score (PRGS). Long-term oncologic outcomes were compared. RESULTS: The cohort comprised 388 patients, including 127, 202, and 59 patients in the doublet, doublet + targeted, and triplet groups, respectively. MR rates were higher in the triplet (68.0%) and doublet + targeted groups (64.2%) when compared with the doublet group (42.4%, p = 0.003). Complete and major PRs were observed in 13.6% and 32.0% of patients, respectively. Higher MR rates were observed after doublet + targeted or triplet regimens, while no difference was observed for PR rates. In multivariate analysis, FOLFIRINOX was independently associated with better overall survival (hazard ratio 0.49, 95% confidence interval 0.25-0.96; p = 0.037). FOLFIRINOX also resulted in a higher rate of severe postoperative complications. CONCLUSIONS: In this retrospective study, a FOLFIRINOX regimen as NACT seemed to result in better long-term outcomes for CRPM patients after complete CRS/HIPEC, although with higher morbidity. Prospective studies are needed, including groups without NACT and those with FOLFIRINOX + bevacizumab.

Influence of Extraperitoneal Metastases on the Curative-Intent Management of Colorectal Peritoneal Metastases.

BACKGROUND: Selected patients with colorectal cancer peritoneal metastasis (CRPM) and extraperitoneal disease could be treated radically with a multimodal approach combining complete cytoreductive surgery, thermoablation, radiotherapy, and systemic and intraperitoneal chemotherapy. The impact of extraperitoneal metastatic sites (EPMS) in this setting remains unclear. PATIENTS AND METHODS: Patients with CRPM undergoing complete cytoreduction in 2005-2018 were grouped in: peritoneal disease only (PDO), one EPMS (1 + EPMS), two or more EPMS (2 + EPMS). A retrospective analysis compared overall survival (OS) and postoperative outcomes. RESULTS: Of 433 patients, 109 had 1 + EPMS and 31 had 2 + EPMS. Overall, 101 patients had liver metastasis, 19 lung metastasis, and 30 retroperitoneal lymph node (RLN) invasion. The median OS was 56.9 months. There was no significant OS difference between PDO and 1 + EPMS groups (64.6 and 57.9 months, respectively), whereas OS was lower in the 2 + EPMS group (29.4 months, p = 0.005). In multivariate analysis, 2 + EPMS [hazard ratio (HR) 2.86, 95% confidence interval (CI) 1.33-6.12, p = 0.007], Sugarbaker's Peritoneal Carcinomatosis Index (PCI) > 15 (HR 3.86, 95% CI 2.04-7.32, p < 0.001), poorly differentiated tumors (HR 2.62, 95% CI 1.21-5.66, p = 0.015), and BRAF mutation (HR 2.10, 95% CI 1.11-3.99, p = 0.024) were independent poor prognostic factors, while adjuvant chemotherapy was beneficial (HR 0.33, 95% CI 0.20-0.56, p < 0.001). Patients with liver resection did not show higher severe complication rates. CONCLUSION: In patients with CRPM selected for a radical surgical approach, limited extraperitoneal disease involving one site, notably the liver, does not seem to significantly impair postoperative results. RLN invasion appeared as a poor prognostic factor in this population.

[Differential diagnostic between hepatocellular carcinoma and hepatoid carcinoma with bone metastasis revelation: What tools can be used?] / Diagnostic différentiel entre un carcinome hépatocellulaire et un carcinome hépatoïde à révélation métastatique osseuse : quels outils sont à disposition ?

Bone metastases of hepatocellular carcinoma (HCC) are rare and disease-revealing bone metastasis are exceptional. Here, we report the case of a 69-year-old man with a cervical vertebral metastasis of hepatocellular carcinoma. Morphological aspect of a metastatic tumor with eosinophilic and polygonal cells raises the question of the differential diagnosis between a localization of a hepatocellular carcinoma or an hepatoid carcinoma, notably when the metastasis is the first clinical manifestation. The morphological aspect by itself does not provide strong enough arguments for diagnosis. Well selected immunohistochemical markers can sometimes help to orientate towards one of the two hypotheses, in particular SALL4 and LIN28 which are in favour of hepatoid carcinoma when both are positive. Finally, as these two entities have different molecular profiles, molecular study can also be helpful to distinguish them. Indeed, HCCs often present TERT promoter, CTNNB1 mutations and IL-6/JAK/STAT pathway activation while hepatoid adenocarcinoma frequently presents chromosome 20 long arm gain. TP53 mutations are found in both entities and are therefore not discriminating. Differential diagnosis is important because the treatment will be that of the primary. Prognostic data for HCC revealed by bone metastasis are scarce, although they seem to be associated with a poor prognosis, with a 1 to 2 months overall survival. There is currently no data for hepatoid adenocarcinoma with bone metastasis.

Non-resectable Malignant Peritoneal Mesothelioma Treated with Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) Plus Systemic Chemotherapy Could Lead to Secondary Complete Cytoreductive Surgery: A Cohort Study.

BACKGROUND: Diffuse malignant peritoneal mesothelioma (DMPM) is an aggressive primary peritoneal neoplasia. At diagnosis, few patients are eligible for a recommended cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Among neoadjuvant strategies, pressurized intraperitoneal aerosol chemotherapy (PIPAC) combined with systemic chemotherapy has been recently proposed. This study evaluated this strategy in a cohort of DMPM patients. METHODS: Patients with DMPM and primary or recurrent non-resectable diseases who received at least one PIPAC procedure in alternation with systemic chemotherapy were included in this retrospective study to analyze oncologic outcomes. RESULTS: Overall, 26 DMPM patients were treated with at least one PIPAC, including 20 patients with no previous CRS. Of 22 patients (85%) who had symptoms, 9 had perceptible ascites. Overall, 79 PIPAC procedures were performed, with half of the patients receiving three PIPAC procedures or more. Among eight patients (31%), 10 adverse events (13% of procedures) were reported, including two severe complications, both corresponding to digestive perforations. Improvement of symptoms was reported for 32% of the patients, whereas control of ascites was noted in 46%. All but one procedure among 14 patients (54%) secondarily treated by CRS-HIPEC were considered complete resections. After a median follow-up period of 29.6 months (95% confidence interval [CI], 17.6-not reached [NR]), the median overall survival period was 12 months (95% CI 11.1-NR). The median progression-free survival (PFS) was significantly better among the patients who underwent resection than among those who did not (33.5 vs 7.4 months; hazard ratio [HR], 0.18; 95% CI 0.06-0.755; p < 0.001). CONCLUSIONS: For patients with initially non-resectable DMPM, PIPAC is feasible for treatment with neoadjuvant intent and could facilitate complete secondary resection.

Non-invasive quantification of acute macrophagic lung inflammation with [11C](R)-PK11195 using a three-tissue compartment kinetic model in experimental acute respiratory distress syndrome.

PURPOSE: Imaging of acute lung inflammation is pivotal to evaluate innovative ventilation strategies. We aimed to develop and validate a three-tissue compartment kinetic model (3TCM) of [11C](R)-PK11195 lung uptake in experimental acute respiratory distress syndrome (ARDS) to help quantify macrophagic inflammation, while accounting for the impact of its non-specific and irreversible uptake in lung tissues. MATERIAL AND METHODS: We analyzed the data of 38 positron emission tomography (PET) studies performed in 21 swine with or without experimental ARDS, receiving general anesthesia and mechanical ventilation. Model input function was a plasma, metabolite-corrected, image-derived input function measured in the main pulmonary artery. Regional lung analysis consisted in applying both the 3TCM and the two-tissue compartment model (2TCM); in each region, the best model was selected using a selection algorithm with a goodness-of-fit criterion. Regional best model binding potentials (BPND) were compared to lung macrophage presence, semi-quantified in pathology. RESULTS: The 3TCM was preferred in 142 lung regions (62%, 95% confidence interval: 56 to 69%). BPND determined by the 2TCM was significantly higher than the value computed with the 3TCM (overall median with interquartile range: 0.81 [0.44-1.33] vs. 0.60 [0.34-0.94], p < 0.02). Regional macrophage score was significantly associated with the best model BPND (p = 0.03). Regional BPND was significantly increased in the hyperinflated lung compartment, compared to the normally aerated one (median with interquartile range: 0.8 [0.6-1.7] vs. 0.6 [0.3-0.8], p = 0.03). CONCLUSION: To assess the intensity and spatial distribution of acute macrophagic lung inflammation in the context of experimental ARDS with mechanical ventilation, PET quantification of [11C](R)-PK11195 lung uptake was significantly improved in most lung regions using the 3TCM. This new methodology offers the opportunity to non-invasively evaluate innovative ventilatory strategies aiming at controlling acute lung inflammation.

[Rosai-Dorfman-Destombes disease with a misleading laryngeal presentation]. / Une maladie de Rosai­Dorfman­Destombes de présentation laryngée trompeuse.

Rosai-Dorfman-Destombes disease is a rare non-Langerhansian cell histiocytosis characterized by the accumulation of large activated histiocytes in the affected tissues with images of emperipolesis. The diagnosis is not really problematic in the classical forms, with a lymph node presentation, whose histology is very suggestive. However, it can be much more difficult in the extra-nodal forms, which are misleading in both their clinical and histological presentation. We report here a case illustrating this diagnostic difficulty. Firstly, clinically, the disease was revealed by an unusual laryngeal location, responsible for acute obstructive respiratory distress and requiring urgent surgical management. Secondly, histologically, the diagnosis was not evoked in the first instance by analysis of the laryngeal lesion. Indeed, there was a not specific appearing polymorphic infiltrate, associating small lymphocytes, plasma cells and numerous histiocytes, without evidence for a lymphoma after immunohistochemistry and lymphocyte clonality analysis. However, after re-examination of the slides, the histiocytes sometimes appeared large or xanthomised and have a PS100+, CD1a-, langerhine- phenotype, with rare images of emperipolesis. These aspects finally suggested the diagnosis of Rosai-Dorfman-Destombes disease, then confirmed by a cervical lymph node biopsy showing characteristic histological features. Simultaneously, NGS analysis of the laryngeal lesion showed a mutation in the MAP2K1 gene, in accordance with the diagnosis. The patient was treated with revlimid and dexamethasone for 6 months, with complete remission, and is currently undergoing maintenance treatment with revlimid.

Clinical and Radiologic Predictors of a Pathologic Complete Response to Neoadjuvant Chemotherapy (NACT) in Patients Undergoing Cytoreductive Surgery for Colorectal Peritoneal Metastases: Results of a Prospective Multi-center Study.

BACKGROUND: Patients undergoing cytoreductive surgery for colorectal peritoneal metastases who have a pathologic complete response (pCR) to neoadjuvant chemotherapy experience a significantly longer survival than those with residual disease. This response is known only after surgery. This study aimed to examine clinical and radiologic predictors of a pCR. METHODS: From July 2018 to December 2019, the study prospectively enrolled 120 patients. The clinical and radiologic findings were compared between patients with and without a pCR. A protocol for pathologic evaluation was followed. RESULTS: A pCR was observed in 34 patients (28.3%). Receiver operating characteristic (ROC) curves showed that patients with a surgical Peritoneal Cancer Index (sPCI) of 3 or lower had an 80% probability of experiencing a pCR, and that patients with a radiologic PCI (rPCI) of 2 or lower had a 70% probability of experiencing a pCR. A pCR was correctly predicted for 47% of the patients by imaging and for 44.4% of the patients by surgical evaluation. The site of primary tumor, the timing of peritoneal metastasis (PM), histology, tumor marker positivity, and mutations in known poor prognostic genes (KRAS) did not differ between the patients with and those without pCR. The primary tumor showed residual disease in 23.5% and regional nodes in 26.4% of the patients with pCR. CONCLUSIONS: The rPCI and sPCI concurred with a pCR in less than 50% of the patients. The patients with a lower PCI had greater concordance. An sPCI of 3 or lower was predictive of a pCR in 80% of the patients. The impact of KRAS mutations on pCR should be evaluated in a larger series. The predictors of pCR and response to systemic chemotherapy should be incorporated in prognostic scores used to select patients for surgery.

Oropharyngeal squamous cell carcinoma: p16/p53 immunohistochemistry as a strong predictor of HPV tumour status.

AIMS: Oropharyngeal squamous cell carcinomas (OPSCC) related to human papillomavirus (HPV) infection have a better prognosis than those without HPV infection. Although p16INK4a overexpression is used as a surrogate marker for HPV infection, 5-20% of p16-positive OPSCC are described as being unrelated to HPV infection, with worse overall survival compared to OPSCC-related HPV. There is therefore a risk of undertreating a proportion of OPSCC patients falsely considered to be HPV-driven because of p16 positivity. TP53 mutations are highly prevalent in OPSCC driven by mutagens in tobacco and alcohol. We describe herein a combined p16/p53 algorithm to predict HPV tumour status in OPSCC. METHODS AND RESULTS: A total of 110 OPSCC were identified in the database of the pathology department and were studied using p16 and p53 immunohistochemistry. For p16-positive or p16-negative/wild-type patterns-p53 (WT-p53) cases (n = 63), DNA in-situ hybridisation for high-risk HPV was performed, and if negative the HPV status was controlled by HPV DNA polymerase chain reaction (PCR) (n = 19). A significant association between TP53 mutation and pattern of p53 expression was found (WT-p53, seven of 16, P < 0.001). The p16-positive/WT-p53 was significantly associated with HPV+ tumour status (p16-positive/WT-p53, 50 of 110, P < 0.001). Interestingly, a subset of p16-positive OPSCC was unrelated to HPV (13.5%, eight of 59), and showed mutant-type staining of p53 expression. CONCLUSIONS: The p16 protein immunopositivity in conjunction with the mutant-type pattern of p53 staining helped to reclassify a subset of p16-positive OPSCC as OPSCC-unrelated HPV. This approach could be routinely applied by pathologists involved in the management of OPSCC, because of their potential therapeutic implications.

Implications of Pathologic Findings in Cytoreductive Surgery Specimens on Treatment of Colorectal Peritoneal Metastases: Results of a Prospective Multicentric Study.

BACKGROUND: A surgical peritoneal cancer index of >20 is often used to exclude patients from cytoreductive surgery for colorectal peritoneal metastases. The pathologic peritoneal cancer index in these patients may be <20. OBJECTIVE: The purpose of this study was to compare the pathologic and surgical findings and to look at potential pathologic prognostic factors. DESIGN: This is a prospective observational study including patients undergoing cytoreductive surgery. SETTINGS: The study was carried out at 3 peritoneal surface malignancy centers, 1 in France and 2 in India. PATIENTS: One-hundred patients were included from July 1, 2018, to June 30, 2019. MAIN OUTCOME MEASURES: The pathologic peritoneal cancer index, peritoneal disease distribution, pathologic response to chemotherapy, factors affecting them and their relation with surgical findings, and potential prognostic value were explored. RESULTS: Ninety percent had colonic primaries. Fifty-one percent had left-sided tumors. The median surgical peritoneal cancer index was 4 (range, 0-35). Upper regions were involved in 32% and small bowel regions in 26%, and their involvement increased with a higher peritoneal cancer index (p < 0.001). The median pathologic peritoneal cancer index was 2 (range, 0-27) and was less than the surgical peritoneal cancer index in 57%. A pathologic complete response was obtained in 25%. Patients with pathologic complete response received more antiepidermal growth factor receptor therapy (p = 0.008); more leucovorin, 5-fluorouracil, and oxaliplatin; and folinic acid, fluorouracilirin, irinotecan hydrochloride, and oxaliplatin (p < 0.001). In 7 patients with a surgical peritoneal cancer index of >20, pathologic peritoneal cancer index was <20 in 4 patients. Disease in the primary tumor/anastomotic site was found in ≈80%. LIMITATIONS: Survival outcomes are not available. CONCLUSIONS: Surgical peritoneal cancer index of >20 should not be the sole factor to exclude patients from surgery, especially in responders to systemic therapies. The pathologic peritoneal cancer index, pathologic response to systemic chemotherapy, and disease distribution in the peritoneal cavity should be meticulously documented. Correlation with survival will define their future prognostic value. The primary anastomotic site is a common site for peritoneal disease and should be carefully evaluated in all patients. See Video Abstract at http://links.lww.com/DCR/B490. IMPLICACIONES DE LOS HALLAZGOS PATOLÓGICOS EN MUESTRAS DE CIRUGÍA CITORREDUCTORA EN EL TRATAMIENTO DE METÁSTASIS PERITONEALES COLORRECTALES: RESULTADOS DE UN ESTUDIO PROSPECTIVO MULTICÉNTRICO: Una ICP quirúrgica de >20 se utiliza a menudo para excluir a los pacientes de la cirugía citorreductora por metástasis peritoneales colorrectales. La PCI patológica en estos pacientes puede ser <20.Comparar los hallazgos patológicos y quirúrgicos y observar los posibles factores pronósticos patológicos.Se trata de un estudio observacional prospectivo que incluye a pacientes sometidos a cirugía citorreductora.El estudio se llevó a cabo en tres centros de malignidad de la superficie peritoneal, 1 en Francia y 2 en India.Se incluyeron 100 pacientes desde el 1 de julio de 2018 al 30 de junio de 2019.No hubo intervención terapéutica.Se exploró la ICP patológica, la distribución de la enfermedad peritoneal, la respuesta patológica a la quimioterapia, los factores que la afectan y su relación con los hallazgos quirúrgicos y el valor pronóstico potencial.El noventa por ciento tenía lesiones primarias colónicas. El 51% tenía tumores del lado izquierdo. La mediana de la ICP quirúrgica 4 [0-35]. Las regiones superiores estuvieron involucradas en el 32% y las regiones del intestino delgado en un 26% y su participación aumentó con una ICP más alta (p <0,001). La mediana de la ICP patológica fue 2 [0-27] y fue menor que la ICP quirúrgica en el 57%. Se obtuvo respuesta patológica completa en el 25%. Los pacientes con respuesta patológica completa recibieron más terapia anti-EGFR (p = 0,008) y más FOLFOX y FOLFIRINOX (p <0,001). En 7 pacientes con una ICP quirúrgica de> 20, la ICP patológica fue menor de 20 en 4 pacientes. Se encontró enfermedad en el tumor primario/anastomósis en casi el 80%.Los resultados de supervivencia no están disponibles.La ICP quirúrgica de> 20 no debería ser el único factor para excluir a los pacientes de la cirugía, especialmente en los que responden a las terapias sistémicas. La PCI patológica, la respuesta patológica a la quimioterapia sistémica y la distribución de la enfermedad en la cavidad peritoneal deben documentarse meticulosamente. La correlación con la supervivencia definirá su valor pronóstico futuro. El sitio anastomótico primario es un sitio común de enfermedad peritoneal y debe evaluarse cuidadosamente en todos los pacientes. Consulte Video Resumen en http://links.lww.com/DCR/Bxxx. (Traducción-Dr. Gonzalo Hagerman).

Multicystic peritoneal mesothelioma treated with cytoreductive surgery followed or not by hyperthermic intraperitoneal chemotherapy: results from a large multicentric cohort.

BACKGROUND: Multicystic peritoneal mesothelioma (MCPM) is a rare, slowly growing, condition prone to recur after surgery. The role of hyperthermic intraperitoneal chemotherapy (HIPEC) added to complete cytoreductive surgery (CRS) remains controversial and difficult to assess. As patients are mostly reproductive age women, surgical approach, and fertility considerations are important aspects of the management. This observational retrospective review aimed to accurate treatment strategy reflections. METHODS: The RENAPE database (French expert centers network) was analyzed over a 1999-2019 period. MCPM patients treated with CRS were included. A special focus on HIPEC, mini-invasive approach, and fertility considerations was performed. RESULTS: Overall 60 patients (50 women) were included with a median PCI of 10 (4-14) allowing 97% of complete surgery, followed by HIPEC in 82% of patients. A quarter of patients had a laparoscopic approach. Twelve patients (20%) recurred with a 3-year recurrence free survival of 84.2% (95% confidence interval 74.7-95.0). The hazard of recurrence was numerically reduced among patients receiving HIPEC, however, not statistically significant (hazard ratio 0.41, 0.12-1.42, p = 0.200). A severe post-operative adverse event occurred in 22% of patients with five patients submitted to a subsequent reoperation. Among four patients with a childbearing desire, three were successful (two had a laparoscopic-CRS-HIPEC and one a conventional CRS without HIPEC). CONCLUSION: MCPM patients treatment should aim at a complete CRS. The intraoperative treatment options as laparoscopic approach, fertility function sparing and HIPEC should be discussed in expert centers to propose the most appropriate strategy.

Identification of intraductal carcinoma of the prostate on tissue specimens using Raman micro-spectroscopy: A diagnostic accuracy case-control study with multicohort validation.

BACKGROUND: Prostate cancer (PC) is the most frequently diagnosed cancer in North American men. Pathologists are in critical need of accurate biomarkers to characterize PC, particularly to confirm the presence of intraductal carcinoma of the prostate (IDC-P), an aggressive histopathological variant for which therapeutic options are now available. Our aim was to identify IDC-P with Raman micro-spectroscopy (RµS) and machine learning technology following a protocol suitable for routine clinical histopathology laboratories. METHODS AND FINDINGS: We used RµS to differentiate IDC-P from PC, as well as PC and IDC-P from benign tissue on formalin-fixed paraffin-embedded first-line radical prostatectomy specimens (embedded in tissue microarrays [TMAs]) from 483 patients treated in 3 Canadian institutions between 1993 and 2013. The main measures were the presence or absence of IDC-P and of PC, regardless of the clinical outcomes. The median age at radical prostatectomy was 62 years. Most of the specimens from the first cohort (Centre hospitalier de l'Université de Montréal) were of Gleason score 3 + 3 = 6 (51%) while most of the specimens from the 2 other cohorts (University Health Network and Centre hospitalier universitaire de Québec-Université Laval) were of Gleason score 3 + 4 = 7 (51% and 52%, respectively). Most of the 483 patients were pT2 stage (44%-69%), and pT3a (22%-49%) was more frequent than pT3b (9%-12%). To investigate the prostate tissue of each patient, 2 consecutive sections of each TMA block were cut. The first section was transferred onto a glass slide to perform immunohistochemistry with H&E counterstaining for cell identification. The second section was placed on an aluminum slide, dewaxed, and then used to acquire an average of 7 Raman spectra per specimen (between 4 and 24 Raman spectra, 4 acquisitions/TMA core). Raman spectra of each cell type were then analyzed to retrieve tissue-specific molecular information and to generate classification models using machine learning technology. Models were trained and cross-validated using data from 1 institution. Accuracy, sensitivity, and specificity were 87% ± 5%, 86% ± 6%, and 89% ± 8%, respectively, to differentiate PC from benign tissue, and 95% ± 2%, 96% ± 4%, and 94% ± 2%, respectively, to differentiate IDC-P from PC. The trained models were then tested on Raman spectra from 2 independent institutions, reaching accuracies, sensitivities, and specificities of 84% and 86%, 84% and 87%, and 81% and 82%, respectively, to diagnose PC, and of 85% and 91%, 85% and 88%, and 86% and 93%, respectively, for the identification of IDC-P. IDC-P could further be differentiated from high-grade prostatic intraepithelial neoplasia (HGPIN), a pre-malignant intraductal proliferation that can be mistaken as IDC-P, with accuracies, sensitivities, and specificities > 95% in both training and testing cohorts. As we used stringent criteria to diagnose IDC-P, the main limitation of our study is the exclusion of borderline, difficult-to-classify lesions from our datasets. CONCLUSIONS: In this study, we developed classification models for the analysis of RµS data to differentiate IDC-P, PC, and benign tissue, including HGPIN. RµS could be a next-generation histopathological technique used to reinforce the identification of high-risk PC patients and lead to more precise diagnosis of IDC-P.

The Pathologic Peritoneal Cancer Index (PCI) Strongly Differs From the Surgical PCI in Peritoneal Metastases Arising From Various Primary Tumors.

BACKGROUND: The surgical peritoneal cancer index (sPCI) is calculated based on a subjective evaluation of the extent of peritoneal disease during surgery. The pathologic PCI (pPCI) may be a more accurate and objective method for determining the PCI. This study aimed to compare the sPCI and pPCI and to study the potential pitfalls and clinical implications of using the pPCI. METHODS: This prospective study (July to December 2018) included all patients undergoing cytoreductive surgery (CRS). The pPCI was calculated for each patient and compared with the sPCI. The impact of potential confounding factors on the difference between pPCI and sPCI was evaluated. RESULTS: Among 191 patients undergoing CRS at four centers, the pPCI and sPCI were concordant for 37 patients (19.3%). The pPCI was lower than the sPCI for 125 patients (65.4%) and higher for 29 patients (15.1%). The concordance between the two groups was maximum for gastric cancer (38.8%) and colorectal cancer (27.6%) and least for mesothelioma (6.7%) and rare primary tumors (5.6%) (p = 0.04). The difference was 0 to 3 points for 119 patients (62.3%), 4 to 5 points for 27 patients (14.1%), and more than 5 points for 45 patients (23.5%). The rate of concordance was not influenced by the use of neoadjuvant chemotherapy (NACT) (p = 0.4), but the difference was greater when NACT was used (p = 0.03). CONCLUSIONS: The pPCI strongly differs from the sPCI for patients undergoing CRS for peritoneal disease and may provide a more accurate evaluation of the peritoneal disease extent. Further studies are needed to determine its prognostic value compared with sPCI, and consensus guidelines are needed for calculating it.

Poorly differentiated neuroendocrine carcinoma of the head and neck: human papillomavirus tumour status/p16 status and impact on overall survival.

AIMS: Poorly differentiated neuroendocrine carcinoma (PDNEC) of the head and neck is a rare high-grade neuroendocrine neoplasm. Human papillomavirus (HPV) status and p16 status are as yet unclear among PDNECs, owing to a lack of statistical analysis. The objective of the present study was therefore to evaluate their potential clinicopathological associations, and their prognostic impact on overall survival in PDNECs of the head and neck, regardless to HPV genotype. METHODS AND RESULTS: All cases of PDNEC of the head and neck between 1998 and 2019 were identified from the database of the Lyon university hospital pathology department (n = 21); for these cases, p16 immunohistochemistry and HPV in-situ hybridisation were performed. Published cases of PDNEC of the head and neck with assessment of HPV status and p16 status were identified in PubMed (n = 57). Local and published cases were pooled for analysis. HPV positive (HPV+) tumour status was found to be significantly associated with oropharyngeal localisation (P < 0.001) and overexpression of p16 (P < 0.001). Multivariate analysis, adjusted on tumour site, histological subtype, p16 status, HPV status, and source of the case, showed that oropharyngeal localisation [hazard ratio (HR) 3.031, 95% confidence interval (CI) 1.257-7.310] and being a small-cell variant (HR 2.859, 95% CI 1.150-7.109) were significant predictors of worse overall survival; HPV+ tumour status was associated with better overall survival (HR 0.388, 95% CI 0.146-0.995). CONCLUSIONS: HPV+ tumour status was associated with oropharyngeal PDNECs and with a better prognosis.

Prognostic impact of combined progression index based on peritoneal grading regression score and peritoneal cytology in peritoneal metastasis.

AIMS: The peritoneal regression grading score (PRGS) and peritoneal cytology (PC) assess response to chemotherapy in peritoneal metastasis (PM) in a setting of palliative treatment by pressurized intraperitoneal aerosol chemotherapy (PIPAC). Progression has been defined as an increase of PRGS between first and third PIPAC procedures (iPRGS). iPRGSand positive peritoneal cytology were not associated with prognostic impact. These results may be explained by a lack of statistical power. Also, it is not known whether the mean or the highest PRGS among taken peritoneal biopsies bears the highest clinical value. We therefore conducted the largest prospective study to investigate the prognostic impact of PGRS, PC, and their combination, designated as combined progression index (CPI). METHODS AND RESULTS: Patients with PM who underwent >3 PIPAC (n = 112) between December 2016 and February 2019 were prospectively included. A significant difference in OS and PFS according to CPI (used highest value of PRGS) was found (OS: CPI-, 83.3, 95% CI [49.8; NA] vs. CPI+, 48.1, 95% CI [38.5; 66.4] months; and PFS (respectively, 59.7, 95% CI [43.0; 96.0] vs. 33.7, 95% CI [30.4; 44.2] months). PRGS or PC had no independent prognostic impact. CPI+ was an independent predictor of worse prognosis, in OS (HR = 5.24, 95% CI [2.07; 13.26]), and PFS (HR = 4.41, 95% CI [1.40; 13.88]). CONCLUSIONS: The CPI based on highest PRGS and PC was found to be independently associated with a worse prognosis for OS and for PFS in the setting of peritoneal metastasis. These results indicate that it should be of interest to systematically take peritoneal fluid for cytological examination and to implement the CPI in the therapeutic decision-making process in the context of PIPAC.

Risk of Omental Metastases in Patients Undergoing Cytoreductive Surgery for Colorectal Peritoneal Metastases.

BACKGROUND: Complete cytoreductive surgery of macroscopic tumor is a potentially curative treatment for patients with colorectal peritoneal metastases. OBJECTIVE: This study aims to determine the risk of microscopic tumor involvement of the greater omentum in patients with normal-looking omentum at the time of cytoreductive surgery for colorectal peritoneal metastases. DESIGN: This was a cohort study. SETTINGS: The prospective BIG-RENAPE database (NCT02823860) was analyzed. PATIENTS: All patients who underwent a complete cytoreductive surgery with greater omentectomy for colorectal peritoneal metastases at a single institution between January 2005 and December 2017 were included. MAIN OUTCOME MEASURE: Data regarding involvement of the greater omentum were extracted from surgical and pathological records. RESULTS: Of 337 patients who underwent cytoreductive surgery for colorectal peritoneal metastases, 241 (71.51%) presented macroscopic omental invasion. Among the 96 patients who underwent a complete cytoreductive surgery with no macroscopic evidence of disease in the greater omentum during surgical exploration, 17 patients (17.70%) had microscopic evidence of tumor in the omentum. Patients with pathological evidence of omental tumor involvement were more likely to have a higher peritoneal cancer index (median 9 vs 4, p = 0.006). LIMITATIONS: No survival analysis could be provided regarding the impact of omentectomy. CONCLUSION: In patients with a normal-looking omentum during surgery for colorectal peritoneal metastases, microscopic tumor was present in 17%. Routine greater omentectomy should be considered in these patients to ensure complete cytoreduction. See Video Abstract at http://links.lww.com/DCR/B262.ClinicalTrials.gov Identifier: NCT02823860 RIESGO DE METÁSTASIS OMENTALES EN PACIENTES SOMETIDOS A CIRUGÍA CITORREDUCTORA, POR METÁSTASIS PERITONEALES COLORRECTALES: La cirugía citorreductora completa del tumor macroscópico, es un tratamiento potencialmente curativo, en pacientes con metástasis peritoneales colorrectales.Determinar el riesgo de afectación tumoral microscópica del epiplón mayor, en pacientes con epiplón de aspecto normal, al momento de la cirugía citorreductora por metástasis peritoneales colorrectales.Este fue un estudio de cohorte.Se analizó la base de datos prospectiva BIG-RENAPE (NCT02823860).Se incluyeron a todos los pacientes sometidos a una cirugía citorreductora completa con omentectomía mayor, por metástasis peritoneales colorrectales, de una sola institución, entre enero de 2005 y diciembre de 2017.Se extrajeron los datos de la afectación del epiplón mayor, de los registros quirúrgicos y patológicos.De 337 pacientes sometidos a cirugía citorreductora por metástasis peritoneales colorrectales, 241 (71.51%) presentaron invasión omental macroscópica. Entre los 96 pacientes sometidos a cirugía citorreductora completa, sin evidencia macroscópica de enfermedad en el epiplón mayor, durante la exploración quirúrgica, 17 pacientes (17,70%) tuvieron en el epiplón, evidencia microscópica de tumor. Los pacientes con evidencia patológica de afectación del tumor omental, fueron más propensos a tener un índice de cáncer peritoneal más alto (mediana 9 frente a 4, p = 0,006).No se pudo obtener ningún análisis de supervivencia, sobre el impacto de la omentectomía.En pacientes con epiplón de aspecto normal, durante la cirugía por metástasis peritoneales colorrectales, estuvo presente el tumor microscópico, en el 17% de los casos. Se debe considerar una omentectomía mayor de rutina en estos pacientes, para asegurar una citorreducción completa. Consulte Video Resumen http://links.lww.com/DCR/B262.Identificador de ClinicalTrials.gov: NCT02823860.