Publications by authors named "Ghassan Allo"

Objective: Substantial lymphovascular space invasion (LVSI) is an important predictor of lymph node (LN) involvement in women with endometrial carcinoma. We studied the prognostic significance of substantial LVSI in patients with 2009-FIGO stage-I uterine endometrioid adenocarcinoma (EC) who all had pathologic negative nodal evaluation (PNNE).

Methods: Pathologic specimens were retrieved and LVSI was quantified (focal or substantial) in women with stage-I EC who had a hysterectomy and PNNE.

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Introduction: The impact of COVID-19 on the placenta is poorly described, particularly among minority women.

Materials And Methods: This is a retrospective case-control study. Micro- and macroscopic placental pathologic findings were compared for 15 COVID-19 positive and 36 negative mothers.

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Objective: The objective of this study was to investigate the prognostic significance of the depth of cervical stromal invasion (CSI) in women with FIGO stage II uterine endometrioid adenocarcinoma (EC).

Methods: Our database of women with EC was quired for patients with stage II EC. Pathologic slides were retrieved and reviewed by gynecologic pathologists to determine cervical stromal thickness and depth of CSI as a percentage of stromal thickness (%CSI).

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Methods for collection of placental tissue at room temperature for metabolic profiling are described. Specimens were excised from the maternal side of the placenta and immediately flash frozen or fixed and stored for 1, 6, 12, 24, or 48 h in 80% methanol. Untargeted metabolic profiling was performed on both the methanol-fixed tissue and the methanol extract.

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Metformin is being actively repurposed for the treatment of gynecologic malignancies including ovarian cancer. We investigated if metformin induces analogous metabolic changes across ovarian cancer cells. Functional metabolic analysis showed metformin caused an immediate and sustained decrease in oxygen consumption while increasing glycolysis across A2780, C200, and SKOV3ip cell lines.

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Few studies have examined if maternal allergic disease is associated with an offspring's neurodevelopment. We hypothesized that Th-2 biased maternal immune function assessed as total serum immunoglobulin (Ig) E is associated with attention deficit hyperactivity disorder (ADHD). Data are from the Wayne County Health, Environment, Allergy, and Asthma Longitudinal Study (WHEALS), a racially and socioeconomically diverse birth cohort in metropolitan Detroit, Michigan.

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Vulvar squamous cell carcinomas (VSCC) represent the most common carcinoma of the female external genitalia, with increasing incidence. Although high-risk human papillomavirus (HPV) infection has long been implicated in the majority of cervical and anal squamous cell carcinomas, there is uncertainty about its prevalence and prognostic impact in VSCC. In this study, we conducted a retrospective integrated morphologic and multimodal HPV analysis of a cohort of 114 VSCC cases treated at the Princess Margaret Cancer Centre/University Health Network, Toronto, Canada between 2000 and 2010.

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Objective: Low-grade serous ovarian cancer (LGSOC) constitutes 5-8% of epithelial ovarian cancers and is refractory to chemotherapy. We and others have shown metformin to cause significant growth inhibition in high-grade ovarian cancer both in vitro and in vivo. Here, we aimed to analyze if metformin was effective in inhibiting proliferation of LGSOC alone and in combination with MEK inhibitor.

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Availability of lung cancer models that closely mimic human tumors remains a significant gap in cancer research, as tumor cell lines and mouse models may not recapitulate the spectrum of lung cancer heterogeneity seen in patients. We aimed to establish a patient-derived tumor xenograft (PDX) resource from surgically resected non-small cell lung cancer (NSCLC). Fresh tumor tissue from surgical resection was implanted and grown in the subcutaneous pocket of non-obese severe combined immune deficient (NOD SCID) gamma mice.

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Malignant pleural mesothelioma (MPM) is a rare but aggressive disease with few therapeutic options. The tumor-stromal interface is important in MPM, but this is lost in cell lines, the main model used for preclinical studies. We sought to characterize MPM patient-derived xenografts (PDX) to determine their suitability as preclinical models and whether tumors that engraft reflect a more aggressive biological phenotype.

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Background: The tumor suppressor p53 is frequently inactivated in non-small cell lung cancer (NSCLC). Activation of the p53 pathway by inhibition of its negative regulator MDM2 may offer an attractive approach for NSCLC therapy. We evaluated the antitumor activity of the small-molecule MDM2 inhibitor RG7388 in patient-derived xenograft (PDX) models of NSCLC.

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Purpose: Although epidermal growth factor receptor (EGFR) -mutated adenocarcinomas initially have high response rates to EGFR tyrosine kinase inhibitors (TKIs), most patients eventually develop resistance. Patient-derived xenografts (PDXs) are considered preferred preclinical models to study the biology of patient tumors. EGFR-mutant PDX models may be valuable tools to study the biology of these tumors and to elucidate mechanisms of resistance to EGFR-targeted therapies.

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Objective: The phosphatidylinositol-3 kinase/serine-threonine kinase PI3K/AKT pathway is postulated to be central to cancer cell development. Activation of this pathway is believed to promote angiogenesis, protein translation and cell cycle progression. A large percentage of endometrial carcinomas have demonstrated mutations within this regulation pathway which result in constitutional activation.

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Aims: Prophylactic hysterectomy with bilateral salpingo-oophorectomy is being increasingly undertaken in patients with Lynch syndrome (LS). The pathological features in such specimens are not well described and, unlike the SEE-FIM protocol for salpingo-oophorectomy specimens in BRCA1/2 mutation carriers and the gastrectomy grossing protocols for patients with CDH1 (E-cadherin) mutations, guidelines have not been devised for the grossing of prophylactic gynaecological specimens from LS patients. We aimed to review the pathological findings in a series of prophylactic gynaecological specimens from LS patients and develop guidelines for the grossing of these specimens.

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Introduction: The prognostic significance of activity biomarkers within the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway was assessed in two independent cohorts of malignant pleural mesothelioma (MPM) patients uniformly treated with a multimodal approach. We specifically assessed expression signatures in a unique set of pre- and postchemotherapy tumor samples.

Methods: Biomarker expression was assessed in samples of two independent cohorts of 107 (cohort 1) and 46 (cohort 2) MPM cases uniformly treated with platinum-based induction chemotherapy followed by extrapleural pneumonectomy from two different institutions, assembled on tissue microarrays.

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Aims: We investigated the sensitivity and specificity of two novel Epidermal growth factor receptor (EGFR) mutation-specific antibodies in the detection of the most common EGFR mutations in lung adenocarcinoma.

Methods And Results: A total of 241 resected lung adenocarcinoma specimens and six resected post-neoadjuvant gefitinib adenocarcinomas were analysed for EGFR mutation using mass spectrometry, fragment analysis and direct PCR sequencing platforms. Tissue arrays and/or full sections of these cases were evaluated using immunohistochemistry with two novel antibodies (clones SP125 and SP111) and two previously reported antibodies (clones 43B2 and 6B6), specific for L858R or 15-nucleotide exon-19 deletion EGFR mutations.

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BAF250a (ARID1A) loss is a frequent event in high-grade endometrial cancers. It has been proposed that ARID1A is a driver gene, with ARID1A mutations occurring secondary to deregulated mismatch repair mechanism in gastric cancers, representing an alternative oncogenic pathway to p53 alteration. The prognostic significance of ARID1A loss is controversial.

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Although different histologic subtypes of epithelial ovarian tumors have long been recognized, their molecular abnormalities have not been fully defined. We examined the prevalence of DNA mismatch repair (MMR) protein loss in these tumors. Tissue microarrays (TMA) of suspected ovarian carcinomas were stained for hMLH1, hMSH2, hMSH6, and hPMS2 and scored separately by 2 groups of investigators.

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Mucinous ovarian carcinomas (MCs) typically do not respond to current conventional therapy. We have previously demonstrated amplification of HER2 in 6 of 33 (18.2%) mucinous ovarian carcinomas (MCs) and presented anecdotal evidence of response with HER2-targeted treatment in a small series of women with recurrent HER2-amplified (HER2+) MC.

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A spectral domain optical coherence tomography (SD-OCT) system and an oral imaging probe have been developed to visualize the microstructural morphology and microvasculature in the human oral cavity. Structural OCT images of ex vivo pig oral tissues with the histology of the same sites were acquired and compared for correlations. Structural in vivo OCT images of healthy human tissue as well as a pathologic site (ulcer) were obtained and analyzed based on the results of the ex vivo pig study, drawing on the similarity between human and swine oral tissues.

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Background: The mismatch repair (MMR) status of tumors is being increasingly recognized as a prognostic, predictive, and possible germline predisposition/Lynch syndrome (LS) biomarker in colorectal cancer and other cancer types, particularly in endometrial cancer. Current methods (clinical history and tumor morphology) to predict MMR deficiency (dMMR) are suboptimal, and implementation of reflex laboratory testing of appropriate tumors has been recommended, a strategy requiring test standardization and clinical coordination.

Methods: Two web-based questionnaires were administered, a general and a specialist laboratory questionnaire, to establish the availability of such tests, requisite clinical/pathology integration, current mode of test initiation, reporting and recommendation practices, and education and attitudes among pathologists.

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It is currently recognized that the pathogenesis of malignancy-associated thrombotic microangiopathy (TMA) is distinct from thrombotic thrombocytopenic purpura. This carries important implications in its classification and its management. Here, we report a case of occult malignancy presenting initially as acute kidney injury secondary to TMA and highlight the importance of considering an underlying malignancy in patients not responding to conventional therapy for TMA.

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Purpose: To map the distribution of microscopic disease (MD) in head-and-neck cancer by analyzing digital images of whole-mounted serial sections of tongue cancer specimens.

Methods And Materials: Ten T1-3 oral tongue cancer specimens were evaluated. The specimens were sliced into 3-mm blocks from which one or more 4-μm slides were taken and digitized to create whole-mounted serial sections.

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