Pulmonary Recurrence of Colorectal Mucinous Adenocarcinoma and Sarcoidosis on 18 F-FDG PET/CT.

ABSTRACT: A 67-year-old woman, previously diagnosed with pulmonary sarcoidosis and sigmoid colon mucinous adenocarcinoma with pulmonary metastasis, showed an enlarged pulmonary nodule in routine follow-up. Because of the absence of treatment for either condition over the past 3 years, the nodule raised concerns of cancer recurrence or sarcoidosis progression. Its distinctive 18 F-FDG PET/CT appearance, compared with other pulmonary lesions, suggested a mucinous histology. The diagnosis was confirmed by pathological examination. This emphasizes the importance of knowledge of the 18 F-FDG PET/CT phenotype of neoplastic histological variants to address challenging diagnostic scenarios.

Spread Through Air Spaces in Stage I to III Resected Lung Adenocarcinomas: Should the Presence of Spread Through Air Spaces Lead to an Upstaging?

In recent years, the concept of spread through air spaces (STAS) has been discussed as an adverse prognostic factor for lung cancer. The aim of our study is to clarify the prognostic role of STAS in relation to the main recognized prognostic factors in a retrospective cohort of 330 European patients who underwent stages I to III lung adenocarcinoma resection. On univariate analysis, the presence of STAS was related to progression-free survival (PFS; hazard ratio [HR]: 1.48; 95% CI: 1.02-2.19; P = 0.038) and overall survival (OS; HR: 1.61; 95% CI: 1.03-2.52; P = 0.50). On multivariate analysis, STAS was related to PFS (HR: 1.51; 95% CI: 1.00-2.17; P = 0.050) and to OS (HR: 1.67; 95% CI: 1.00-2.81; P = 0.050). We showed that the presence of STAS was associated with lower PFS, equivalent to the next pathologic T stage, especially the median PFS of T3 stages without STAS was at 62.8 months while the median PFS of T3 stages with STAS was at 15.7 months, closer to the median PFS of 17.4 months in T4 stages. To conclude, STAS is an independent prognostic factor of PFS in this European cohort and is close to significance for OS. We suggest that the presence of STAS might lead to an upstaging of lung adenocarcinoma.

Usefulness of an RNA extraction-free test for the multiplexed detection of ALK, ROS1, and RET Gene Fusions in Real Life FFPE Specimens of Non-Small Cell Lung Cancers.

BACKGROUND: ALK, ROS1 and RET rearrangements occur, respectively, in 5%, 2%, and 1% non-small cell lung cancers (NSCLC). ALK and ROS1 fusion proteins detection by immunohistochemistry (IHC) has been validated for rapid patient screening, but ROS1 fusions need to be confirmed by another technique and no RET IHC test is available for clinical use. RESEARCH DESIGN AND METHODS: We report herein the usefulness of the HTG EdgeSeq Assay, an RNA extraction-free test combining a quantitative nuclease protection assay with NGS, for the detection of ALK, ROS1 and RET fusions from 'real-life' small NSCLC samples. A total of 203 FFPE samples were collected from 11 centers. They included 143 rearranged NSCLC (87 ALK, 39 ROS1, 17 RET) and 60 ALK-ROS1-RET negative controls. RESULTS: The assay had a specificity of 98% and a sensitivity for ALK, ROS1 and RET fusions of 80%, 94% and 100% respectively. Among the 19 HTG-assay false negative samples, the preanalytical conditions were identified as the major factors impacting the assay efficiency. CONCLUSIONS: Overall, the HTG EdgeSeq assay offers comparable sensitivities and specificity than other RNA sequencing techniques, with the advantage that it can be used on very small and old samples collected multicentrically.

P33-A110†Ex vivo models of corneal epithelial regeneration in bioreactor: respective roles of limbal, conjunctival and corneal epithelia.

PURPOSE: Human corneas preserved in bioreactor (BR) are characterized by not only a better endothelial viability, but also a more differentiated and stratified epithelium compared to corneas preserved in organoculture. By using corneal preservation in BR, we aimed to analyze the respective contribution of corneal (C), limbal (L), and conjunctival (Conj) epithelia in corneal epithelial regeneration. METHODS: Five pairs of corneas from body donation to Science were used with a death-to-collection time <20 hours. A 3- to 5-mm-wide conjunctival flange was kept intact. Five patterns were set up by complete mechanical removal of 1, 2, or 3 epithelia (-): C-L+Conj+, C-L-Conj+, C-L+Conj-, C+L-Conj-, C-L-Conj- (control) (n=2 for each pattern). The L epithelia was destroyed by scraping and thermocoagulation. Corneas were then kept in BR (21mmHg, 2.5µl/min of Corneamax Eurobio, 31°C) for 3 weeks to allow epithelial regeneration. The epithelium was then analyzed using immunofluorescence (IF) on flat mounted cornea by targeting CK12 (corneal epithelium) and CK15 (limbal epithelium). Cell nuclei were counterstained with DAPI. Corneal transparency was quantified using a transparometer. RESULTS: No epithelium was reconstituted in the C-L-Conj- control group. In the other 4 models including the C-L-Conj+ group, the cornea was transparent and covered by a pluristratified corneal epithelium, characterized by CK12 expression. CONCLUSION: In this BR model, conjunctival epithelial cells alone allowed the regeneration of a typical corneal epithelium whereas corneal epithelium was able to migrate to the limbus and conjunctiva. We hypothesize that all 3 ocular surface epithelia contain stem cells or progenitors able to migrate throughout the cornea and restore the corneal epithelium independently of each other. The main difference between our ex vivo model and in vivo situation is the absence of neovascularization. This suggests that the main cause of limbic insufficiency is due to the loss of the anti-angiogenic barrier rather than the loss of limbic stem cells.

Investigating the Role of TGF-ß Signaling Pathways in Human Corneal Endothelial Cell Primary Culture.

Corneal endothelial diseases are the leading cause of corneal transplantation. The global shortage of donor corneas has resulted in the investigation of alternative methods, such as cell therapy and tissue-engineered endothelial keratoplasty (TEEK), using primary cultures of human corneal endothelial cells (hCECs). The main challenge is optimizing the hCEC culture process to increase the endothelial cell density (ECD) and overall yield while preventing endothelial-mesenchymal transition (EndMT). Fetal bovine serum (FBS) is necessary for hCEC expansion but contains TGF-ßs, which have been shown to be detrimental to hCECs. Therefore, we investigated various TGF-ß signaling pathways using inhibitors to improve hCEC culture. Initially, we confirmed that TGF-ß1, 2, and 3 induced EndMT on confluent hCECs without FBS. Using this TGF-ß-induced EndMT model, we validated NCAM as a reliable biomarker to assess EndMT. We then demonstrated that, in a culture medium containing 8% FBS for hCEC expansion, TGF-ß1 and 3, but not 2, significantly reduced the ECD and caused EndMT. TGF-ß receptor inhibition had an anti-EndMT effect. Inhibition of the ROCK pathway, notably that of the P38 MAPK pathway, increased the ECD, while inhibition of the ERK pathway decreased the ECD. In conclusion, the presence of TGF-ß1 and 3 in 8% FBS leads to a reduction in ECD and induces EndMT. The use of SB431542 or LY2109761 may prevent EndMT, while Y27632 or Ripasudil, and SB203580 or SB202190, can increase the ECD.

T2-Fluid-attenuated inversion recovery (FLAIR) pseudoprogression in patients with anaplastic oligodendrogliomas treated with procarbazine, lomustine and vincristine (PCV) chemotherapy alone.

BACKGROUND: Pseudoprogression in gliomas has been extensively described after radiotherapy with or without chemotherapy, but not after chemotherapy alone. Here we describe the occurrence of pseudoprogression in patients with anaplastic oligodendrogliomas treated with postoperative procarbazine, lomustine and vincristine (PCV) chemotherapy alone. METHODS: We retrospectively reviewed the medical and radiological files of patients with 1p/19q codeleted, IDH-mutant anaplastic oligodendrogliomas treated with PCV chemotherapy alone who presented magnetic resonance imaging (MRI) modifications suggestive of tumour progression and in whom the final diagnosis was a pseudoprogression. RESULTS: We identified six patients. All patients underwent a surgical resection and were treated with PCV chemotherapy without radiotherapy. After a median of 11 months following the initiation of chemotherapy (range: 3-49 months), the patients developed asymptomatic white matter MRI modifications around the surgical cavity leading to the suspicion of a tumour progression. These modifications appeared as hyperintense on T2-fluid-attenuated inversion recovery (FLAIR) sequence, hypointense on T1 sequence, and lacked mass effect (0/6), contrast enhancement (0/6), restriction on diffusion-weighted imaging (0/4), relative cerebral blood volume (rCBV) increase on perfusion MRI (0/4), and hypermetabolism on 18 F-fluoro-L-dopa positron emission tomography (18 F-DOPA PET) scan (0/3). One patient underwent a surgical resection demonstrating no tumour recurrence; the five other patients were considered as having post-therapeutic modifications based on imaging characteristics. After a median follow-up of 4 years all patients were progression-free. CONCLUSIONS: Anaplastic oligodendroglioma patients treated with postoperative PCV chemotherapy alone occasionally develop T2/FLAIR hyperintensities around the surgical cavity that can wrongly suggest tumour progression. Multimodal imaging and close follow-up should be considered in this situation.

Technique of flat-mount immunostaining for mapping the olfactory epithelium and counting the olfactory sensory neurons.

The pathophysiology underlying olfactory dysfunction is still poorly understood, and more efficient biomolecular tools are necessary to explore this aspect. Immunohistochemistry (IHC) on cross sections is one of the major tools to study the olfactory epithelium (OE), but does not allow reliable counting of olfactory sensory neurons (OSNs) or cartography of the OE. In this study, we want to present an easy immunostaining technique to compensate for these defects of IHC. Using the rat model, we first validated and pre-screened the key OSN markers by IHC on cross sections of the OE. Tuj-1, OMP, DCX, PGP9.5, and N-cadherin were selected for immunostaining on flat-mounted OE because of their staining of OSN dendrites. A simple technique for immunostaining on flat-mounted septal OE was developed: fixation of the isolated septum mucosa in 0.5% paraformaldehyde (PFA) preceded by pretreatment of the rat head in 1% PFA for 1 hour. This technique allowed us to correctly reveal the olfactory areas using all the 5 selected markers on septum mucosa. By combining the mature OSN marker (OMP) and an immature OSN marker (Tuj-1), we quantified the mature (OMP+, Tuj-1-), immature (OMP-, Tuj-1+), transitory (OMP+, Tuj-1+) and total OSN density on septal OE. They were respectively 42080 ± 11820, 49384 ± 7134, 14448 ± 5865 and 105912 ± 13899 cells per mm2 (mean ± SD). Finally, the same immunostaining technique described above was performed with Tuj-1 for OE cartography on ethmoid turbinates without flat-mount.

Challenging Metastatic Melanoma to the Lung With p40 Expression: A Diagnostic Pitfall, Case Report.

p40 immunohistochemistry is a cornerstone of histopathological examination for non-small cell lung carcinoma. p40 is an isoform of p63 and is reported to be highly specific for the diagnosis of squamous cell carcinoma. Very rare pitfalls are reported for this antibody, and p40 is typically negative in melanoma. A 66-year-old patient was admitted for multiple hemorrhagic brain tumors evocative of secondary tumors. On imaging, a 26 mm lung tumor was detected, and a biopsy of the lung tumor was performed. The tumor was stained by melanic markers and diffusely stained by p40 and p63. Molecular analysis found a somatic p.Asn581Ser (c.1742A>G) point mutation in exon 15 of BRAF and a p.Arg80Ter (c.238C>T) germline variant of CDKN2A , a predisposing mutation to melanoma. This case report highlights the importance of clinical, pathologic, and molecular correlation.

Dropless penetrating keratoplasty using a subconjunctival dexamethasone implant: safety pilot study.

BACKGROUND/AIM: Rejection is the main cause of graft failure after penetrating keratoplasty (PK). Its prevention by repeated instillation of steroid eye-drops has not evolved in decades. Poor adherence and discontinuous nature of eye-drop treatment may explain some PK failures. In a rabbit model, we previously demonstrated that a subconjunctival dexamethasone implant was well tolerated and prevented rejection efficiently in the first 5-6 weeks. This clinical trial investigates its tolerance and safety after PK. METHODS: Single-centre, phase II non-randomised tolerance and safety pilot study (NCT02834260). Designed to analyse the risk of elevated intraocular pressure (IOP), discomfort and resorption time. Fourteen patients with a low rejection risk indication of PK were enrolled between January 2017 and August 2018. The implant was injected in the 12 o'clock position, 5 mm from the limbus, at the end of PK. A steroid eye-drop treatment was planned when implant resorption was complete. Patients were monitored regularly for 12 months: IOP (main outcome measure at 1 month), discomfort and redness scores, implant status, rejection episode and central corneal thickness by optical coherence tomography. An independent data safety monitoring committee verified safety aspects. RESULTS: No increase in IOP or other adverse event related to the implant was observed. Average resorption time was 6 weeks. The switch to steroid eye-drops was uneventful. One patient, included despite preoperative corneal neovascularisation (unintended protocol deviation) experienced a rejection. CONCLUSIONS: This is the first proof of concept that dropless immunosuppression is possible after low rejection risk PK. TRIAL REGISTRATION NUMBER: NCT02834260.

Value of immunohistochemistry in crushed areas of pulmonary neuroendocrine carcinoma.

Immunohistochemical demonstration of neuroendocrine differentiation is often performed in routine diagnostic practice for lung neuroendocrine carcinoma. However, these carcinomas are often crushed, especially on small specimens. The value of immunohistochemistry on crushed areas is not known. We aimed to assess the value of immunohistochemical markers in crushed areas. We performed a retrospective study of 299 patients with a diagnosis of pulmonary neuroendocrine carcinoma. We showed that the markers TTF-1, synaptophysin, chromogranin A, CD56, and INSM1 were more often negative in crushed areas compared with well-preserved areas. The proliferation index with anti-Ki67 was decreased but remained on average around 90%. For all markers, the percentage of labeled cells was lower than in the preserved areas. Finally, we show that cases without labeling in the crushed areas and maintained labeling in the non-crushed areas have a lower percentage of labeling than cases without this labeling mismatch. Finally, there were no false positives of these stains. Neuroendocrine markers are valid in crushed areas when positive. However, the percentage of labeled cells may be lower than on preserved areas and lead to false negatives. Finally, the proliferation index, although decreased, remains close to that on preserved areas.

Anti-CK7/CK20 Immunohistochemistry Did Not Associate with the Metastatic Site in TTF-1-Negative Lung Cancer.

Anti-CK7 and anti-CK20 immunohistochemistry is sometimes used to establish a diagnosis of primary lung cancer. We performed a retrospective study on the value of anti-CK7 and anti-CK20 immunohistochemistry in 359 biopsies of patients with suspected lung carcinoma in order to assess the usefulness of these antibodies in the evaluation of lung tumors in biopsies. Our results showed TTF-1 positivity in 73.3% of patients. EGFR mutations and ALK rearrangements were significantly different between TTF-1 positive and TTF-1 negative tumors (p < 0.001 and p = 0.023, respectively). Our results show a significant difference (p < 0.001) between TTF-1 positive and TTF-1 negative carcinomas with a median survival of 21.97 months (CI95% = 17.48−30.9 months) and 6.52 months (CI95% = 3.34−10.3 months), respectively. In the group of TTF-1 negative patients, anti-CK7 and CK20 immunohistochemistry was performed in 70 patients and showed CK7+/CK20- staining in 61 patients (87.1%), CK7-/CK20- in 4 patients (5.7%), CK7+/CK20+ in 3 patients (4.3%), and CK7-/CK20- in 2 patients (2.8%). No specific or molecular pattern was found in these groups of CK7/CK20 combinations. In total, this work brings arguments concerning the uselessness of anti-CK7/CK20 immunohistochemistry in the case of suspicion of primary lung cancer in biopsies.

Spread Through Air Spaces (STAS) Is an Independent Prognostic Factor in Resected Lung Squamous Cell Carcinoma.

Objective: There is no histoprognostic grading for lung squamous cell carcinoma (LUSC). Different prognostic factors have been described in the recent literature and are not always studied in parallel. Our objective was to search for morphological histopathological prognostic factors in LUSC. Materials and Methods: In this single-center retrospective study of 241 patients, all patients with LUSC who underwent surgical excision over a 12-year period were included. The primary endpoint was 5-year overall survival. Results: STAS was present in 86 (35.7%) patients. The presence of Spread Through Air Spaces (STAS) was correlated with tumor location (p < 0.001), pathological stage (p = 0.039), tumor differentiation (p = 0.029), percentage of necrosis (p = 0.004), presence of vascular and/or lymphatic emboli, budding (p = 0.02), single cell invasion (p = 0.002) and tumor nest size (p = 0.005). The percentage of tumor necrosis was correlated with the overall survival at 5 years: 44.6% of patients were alive when the percentage of necrosis was ≥50%, whereas 68.5% were alive at 5 years when the necrosis was <30% (p < 0.001). When vasculolymphatic emboli were present, the percentage of survival at 5 years was 42.5% compared to 65.5% when they were absent (p = 0.002). The presence of isolated cell invasion was correlated with a lower 5-year survival rate: 51.1% in the case of presence, versus 66% in the case of absence (p = 0.02). In univariate analysis, performance status, pathological stage pT or pN, pleural invasion, histopathological subtype, percentage of tumor necrosis, vasculolymphatic invasion, single-cell invasion, budding and tumor nest size correlated with the percentage of survival at 5 years. On multivariate analysis, only STAS > 3 alveoli (HR, 2.74; 95% CI, 1.18−6.33) was related to overall survival. Conclusion: In conclusion, extensive STAS is an independent factor of poor prognosis in LUSC. STAS is correlated with the presence of other poor prognostic factors such as emboli and pleural invasion and would reflect greater tumor aggressiveness.

WHO grading system for invasive pulmonary lung adenocarcinoma reveals distinct molecular signature: An analysis from the cancer genome atlas database.

Lung adenocarcinoma grading has gained interest in the past years. Recently a three-tier tumor grading was proposed showing that it is related to patients' prognosis. Nevertheless, the underlying molecular basis of this morphological grading remains partly unknown. The aim of our work is to take advantage of The Cancer Genome Atlas lung adenocarcinoma (TCGA_LUAD) cohort to describe the molecular data associated to tumor grading. We performed a study on publicly available data of the TCGA database first by assessing a tumor grade on downloadable tumor slides. Secondly we analyzed the molecular features of each tumor grade group. Our work was performed on a study group of 449 patients. We show that aneuploidy score was significantly different between grade 2 and grade 3 groups with different chromosomal imbalance (p < 0.001). SCGB1A1 mRNA expression was higher in grade 2 (p = 0.0179) whereas NUP155, CHFR, POLQ and CDC7 have a higher expression in grade 3 (p = 0.0189, 0.0427, 0.0427 and 0.427 respectively). GZMB and KRT80 have a higher methylation of DNA in grade 2 (p = 0.0201 and 0.0359 respectively). MT1G, CLEC12B and NDUFA7 have a higher methylation of DNA in grade 3 (p < 0.001, 0.0246 and 0.0359 respectively). We showed that the number of activated pathways is different between grade 2 and grade 3 patients (p = 0.004). We showed that differentially expressed genes by mRNA analysis and DNA methylation analysis involve several genes implied in chemoresistance. This could suggest that grade 3 lung adenocarcinoma might be more resistant to chemotherapy.