Challenges and limitation of MTAP immunohistochemistry in diagnosing desmoplastic mesothelioma/sarcomatoid pleural mesothelioma with desmoplastic features.

AIM: Genomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear. METHODS AND RESULTS: We evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity. CONCLUSIONS: MTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available.

Genomic-based ancillary assays offer improved diagnostic yield of effusion cytology with potential challenges in malignant pleural mesothelioma.

BRCA1-associated protein 1 (BAP1) or methylthioadenosine phosphorylase (MTAP) immunohistochemistry (IHC) or 9p21 fluorescence in situ hybridization (FISH) are useful for the diagnosis of malignant pleural mesothelioma (MPM). However, the effect of these assays on the diagnostic yield of effusion cytology in MPM cases with suspicious cytomorphology or the diagnostic challenges in BAP1 or MTAP IHC have not been fully elucidated. Two cohorts of cytologic preparations obtained from pleural effusions were examined: MPM cases in cohort 1 were used to evaluate whether BAP1 or MTAP IHC or 9p21 FISH increase the diagnostic yield of effusion cytology; cohort 2 included cases suspicious for MPM, to which BAP1 or MTAP IHC was applied to clarify the challenges in the clinical assessment of these assays. In cohort 1 (n = 28), either assay elevated 62.5% of class II or III cases to class V. In cohort 2 (n = 139), 21.7% of BAP1 immunocytochemistry in smears and 10.6% of BAP1 IHC and 9.4% of MTAP IHC in cell blocks, were identified to be challenging. The application of genomic-based assays increased the diagnostic yield of effusion cytology in the diagnosis of MPM. However, diagnostic challenges limit the application of these assays in some cases.

Morphological difference between pleural mesothelioma cells in effusion smears with either BAP1 loss or 9p21 homozygous deletion and reactive mesothelial cells without the gene alterations.

We previously characterized the morphological characteristics of malignant pleural mesothelioma (MPM) cells with 9p21 homozygous deletion (HD) using a combination of the virtual microscopy and fluorescence in situ hybridization (FISH). In this study, we investigated whether MPM cells with BRCA1-associated protein 1 (BAP1) loss show the same morphological characteristics identified in MPM cells with 9p21 HD. MPM cells with either BAP1 loss detected by immunocytochemistry (ICC) or 9p21 HD detected by FISH were identified via virtual microscopy prior to ICC or FISH, followed by analysis and quantification of their morphological characteristics. MPM cells with BAP1 loss or 9p21 HD exhibited significantly more frequent cell-in-cell engulfment, multinucleation, and larger multicellular clusters composed of more than 10 cells than reactive mesothelial cells. In conclusion, MPM cells with BAP1 loss or 9p21 HD share similar cytological features, indicating that the same morphological criteria can be used to detect MPM cells harboring such genetic aberrations.

Clinical predictors of bevacizumab-associated intestinal perforation in non-small cell lung cancer.

Background Bevacizumab (Bev) is generally well-tolerated, and Bev-associated intestinal perforation (BAP) is a rare albeit serious side effect in cases of non-small cell lung cancer (NSCLC). Therefore, the present study aimed to identify clinical predictors of BAP to help predict and manage the development of life-threatening intestinal complications among patients receiving Bev. Methods This retrospective study evaluated demographic, clinical, and treatment factors for patients with NSCLC who were treated with Bev between February 2010 and August 2015 at our center. Results We identified 314 regimens (208 patients; median age: 65 years; 115 women) for analysis, which included 119 first-line regimens, 74 s-line regimens, and 121 third-line or later regimens. BAP occurred in 7 cases (2.23% among all regimens and 3.37% among all patients), which generally occurred during first- or second-line treatment and was caused by ulcerative colitis (1 case), colon diverticulitis (1 case), and idiopathic perforations (5 cases). Univariate analyses revealed that BAP was significantly associated with deteriorating PS during the first cycle of chemotherapy (odd ratio [OR]: 11.07, 95% confidence interval [CI]: 2.37-51.63, p = 0.0022), grade ≥ 3 diarrhea (OR: 11.37, 95% CI: 2.37-54.50, p = 0.0024), febrile neutropenia (OR: 9.16, 95% CI: 1.98-42.49, p = 0.0047), and stomatitis (OR: 4.60, 95% CI: 1.01-21.04, p = 0.0492). Conclusions Among patients with NSCLC, BAP was associated with deteriorating PS during the first cycle of chemotherapy, grade ≥ 3 diarrhea, febrile neutropenia, and stomatitis. Therefore, careful observation is needed for patients with NSCLC who receive Bev in any line of treatment, especially if they develop serious side effects that affect their PS or mucous membrane.

Grade 4 asbestosis does not extend directly from the respiratory bronchiole to the peripheral lung.

AIMS: To confirm whether or not grade 4 asbestosis progresses from the respiratory bronchiole to the peripheral lung. METHODS AND RESULTS: We examined retrospectively the autopsy or lobectomy specimens from 31 cases (29 males; mean age 64 years) satisfying the pathological criteria of grade 4 asbestosis. Asbestos bodies (ABs) were quantified in samples of dissolved lung and in tissue preparations on glass slides. Respiratory bronchiolar lesions were graded as 0, 1 and ≥2. Grade 4 asbestosis was subdivided into an atelectatic induration (AI) and usual interstitial pneumonia pattern (UIP pattern). Five, 10, and 16 cases had grades 0, 1 or ≥2 lesions, respectively, with mean respective numbers of ABs in dissolved lung of 117 000/g dry lung, 468 000/g and 968 000/g; and in specimens on glass slides of seven ABs/cm2 of tissue slice, 34 ABs /cm2 and 195 ABs /cm2 . The differences were significant. Fifteen and 16 cases showed AI and UIP patterns, respectively, with mean respective numbers of ABs in dissolved lung of 1 006 000/g dry lung and 354 000/g, and 186 and 56 ABs/cm2 on glass slides. The differences were significant. AI patterns originated in subpleural lobules or subpleural zonal areas and UIP patterns originated in subpleural, peripheral lobules. CONCLUSIONS: Grade 4 asbestosis does not start in the respiratory bronchiole. The presence of a grade 1 lesion is not required for the diagnosis of grade 4 asbestosis.

BAP1 immunohistochemistry and p16 FISH results in combination provide higher confidence in malignant pleural mesothelioma diagnosis: ROC analysis of the two tests.

Differentiation of malignant pleural mesothelioma (MPM) from benign mesothelial proliferation remains problematic. Loss of nuclear staining of BRCA1-associated protein 1 (BAP1; detected using immunohistochemistry (IHC)) and homozygous deletion (HD) of p16 (detected using fluorescence in situ hybridization (FISH)) are useful for differentiation of MPM from reactive mesothelial hyperplasia (RMH), but the correlation between BAP1 expression loss and p16 HD has not been fully described. We performed BAP1 IHC and p16-specific FISH for 40 MPM and 20 RMH cases, and measured proportions of cells showing BAP1 expression and p16 HD for each case. The diagnostic accuracy for MPM and the cut-off values of the two methods were assessed using receiver operating characteristic (ROC) analysis. BAP1 expression loss, p16 HD and coexistence of both were present in 27 (67.5 %), 27 (67.5 %) and 17 (42.5 %) MPM cases, respectively. Three MPM cases (7.5 %) and all 20 RMH cases had neither BAP1 loss nor p16 HD. There was no correlation between the results of the two methods. Their combination showed higher sensitivity (92.5 %, 37/40) and estimated probability than BAP1 IHC and p16-specific FISH used alone. BAP1 IHC and p16-specific FISH have independent diagnostic value, and have increased reliability when used in combination, for MPM diagnosis.

Radial endobronchial ultrasound with a guide sheath for diagnosis of peripheral cavitary lung lesions: a retrospective study.

BACKGROUND: Radial endobronchial ultrasound with a guide sheath (EBUS-GS) has improved the diagnostic outcomes of peripheral lung lesions. However, to our knowledge, reports on the use of EBUS-GS for diagnosis of cavitary lesions are unavailable. Therefore, this study aimed to assess the effectiveness and safety of EBUS-GS for diagnosis of peripheral cavitary lung lesions (PCLLs). METHODS: This study was a single-institution retrospective review of PCLLs examined by using EBUS-GS between July 2013 and October 2015. The diagnostic results of different EBUS-GS samples, including cytologic, histopathologic, and microbiologic samples, were analysed separately. RESULTS: Of 696 radial EBUS procedures performed during the study period, 50 were performed for examination of PCLLs. The overall diagnostic yield for EBUS-GS was 80 % (40/50). Regarding 27 malignant lesions, the diagnostic yields for cytologic and histopathologic samples were 63.0 % (17/27) and 74.1 % (20/27), respectively. Regarding 23 benign lesions, the diagnostic yields for histopathologic and microbiologic samples were 69.6 % (16/23) and 47.8 % (11/23), respectively. Uni- and multivariate analyses indicated that the EBUS probe being within the lesion was the only factor significantly associated with increased diagnostic yield (odds ratio, 7.04; P = 0.03). Although pulmonary infection occurred after the procedure in 1 patient (2.0 %), no other complications, including pneumothorax or significant haemorrhage, were reported. CONCLUSION: EBUS-GS was found to be an effective and safe procedure for diagnosis of PCLLs.

Deletion status of p16 in effusion smear preparation correlates with that of underlying malignant pleural mesothelioma tissue.

Differentiating malignant pleural mesothelioma (MPM) cells morphologically from reactive mesothelial hyperplasia cells is problematic. Homozygous deletion (HD) of p16 (CDKN2A), detected by FISH, is a good marker of malignancy and is useful to differentiate between these cells. However, the correlation between the p16 status of effusion smears and that of the underlying MPM tissues has not been investigated. We used p16-specific FISH to investigate 20 cases of MPM from which both effusion cytologic smears and histologic specimens were available. In five cases, histologic specimens included both an invasive component and surface mesothelial proliferation. In 14 cases (70%), MPM cells in both tissue sections and effusion smears were p16 HD-positive. Conversely, MPM cells in the remaining six tumors (30%) were p16 HD-negative in both tissue sections and effusion smears. For all five MPM cases with surface mesothelial proliferations and invasive components, the effusion smears, surface mesothelial proliferations, and invasive MPM components all displayed p16 deletion. Moreover, the extent to which p16 was deleted in smears highly correlated with the extent of p16 deletion in tissues. The p16 deletion percentages were also similar among smears, tissue surface proliferations, and invasive components. In cases with clinical and radiologic evidence of a diffuse pleural tumor, detection of p16 deletion in cytologic smear samples may permit MPM diagnosis without additional tissue examination. However, the absence of p16 deletion in cytologic smear samples does not preclude MPM.

[STUDY OF DIRECT TB-LAMP USING NON-CENTRIFUGAL SPUTUMS ABOUT EFFICIENCY FOR RAPID DIAGNOSIS OF TUBERCULOSIS].

OBJECTIVE: To evaluate the efficiency of the direct tuberculosis-loop-mediated isothermal amplification (TB-LAMP) assay by using non-centrifuged sputum samples. STUDY PERIOD AND METHODS: The study was conducted between June 2013 and February 2014. We collected 111 sputum samples from patients who had been radiographically diagnosed with tuberculosis and had not received any treatments for longer than 5 days. In the direct TB-LAMP assay, a loop-mediated isothermal amplification kit and 60-µL sputum samples were used. A direct smear microscopy test was used as the smear test. Then, the same sputum samples were processed with a CCE pretreatment reagent, and 100 µL of the solution samples were cultured by using the mycobacterial growth indicator tube (MGIT) culture method. RESULTS: Forty-six of the 111 samples were positive in the smear microscopy tests. All the smear-positive samples were positive in both the MGIT and direct TB-LAMP assay (100%). The mean positive detection time with the direct TB-LAMP assay was 13 minutes 55 seconds. Of 56 smear-negative and MGIT positive samples, 44 (78.6%) were judged to be positive using the direct TB-LAMP assay, with a mean positive detection time of 15 minutes 59 seconds. DISCUSSION: The direct TB-LAMP assay using non-centrifuged sputum samples was demonstrated to have a high detection rate and thus may be considered useful for rapid and effective tuberculosis diagnosis.

Comparison of the clinical courses and chemotherapy outcomes in metastatic colorectal cancer patients with and without active Mycobacterium tuberculosis or Mycobacterium kansasii infection: a retrospective study.

BACKGROUND: Although active Mycobacterium tuberculosis (MTB) or Mycobacterium Kansasii (MK) infection could be present in patients with metastatic colorectal cancer (m-CRC), no study is available on the clinical courses and chemotherapy outcomes of these patients. The present study therefore aimed to retrospectively examine whether m-CRC patients with and without active MTB or MK infection could receive cancer chemotherapy similarly. METHODS: This study enrolled 30 m-CRC patients who received first-line chemotherapy between January 31, 2006 and January 31, 2013 at our institution, The clinical courses and tumor response of those with and without active MTB or MK infection were examined and compared. RESULTS: Of 30 m-CRC patients, 6 had active MTB infection, 1 with active MK and the other 23 had neither MTB nor MK. No significant demographic differences were observed between patients with MTB or MK and those without. Chemotherapy response rates of all patients, those with MTB or MK, and those without were 40.0%, 28.6% and 43.5%, respectively. Among patients with MTB or MK, 1 treated with bevacizumab experienced grade-3 hemoptysis while others did not report any severe toxicity. Median survival time of all studied patients, those with MTB or MK, and those without was 26.3, 36.7 and 22.6 months, respectively. No significant difference in overall survival was observed between patients with MTB or MK and those without. Multivariate analysis revealed that performance status and liver metastasis were significant prognostic factors of overall survival (P = 0.004 and 0.030, respectively), whereas other factors, including MTB or MK infection, were not. In our study, all 7 patients with MTB or MK did not experience infection relapse during or after cancer chemotherapy. CONCLUSIONS: Our results indicate that m-CRC patients with MTB or MK should be able to safely and effectively continue cancer chemotherapy to subsequently achieve comparable survival duration to those without the infection if they receive proper MTB or MK treatment.

Excimer laser coronary atherectomy with distal protection for neoatherosclerosis rupture: a case report.

Background: Neoatherosclerosis, a prominent contributor to in-stent restenosis (ISR), persists as a formidable challenge during percutaneous coronary intervention. Excimer laser coronary atherectomy (ELCA) and embolic protection devices may help reduce coronary flow disturbance from procedure-related distal embolization. Case summary: A 71-year-old man experienced in-stent neoatherosclerosis rupture-related non-ST segment elevation myocardial infarction. Multidisciplinary intracoronary imaging, including intravascular ultrasound and optical coherence tomography (OCT), suggested that the ISR was caused by a neoatherosclerosis rupture that can potentially lead to distal embolization. Excimer laser coronary atherectomy (fluence, 45 mJ/mm2 and frequency, 25 pulse/s) using a 1.7 mm concentric catheter was performed with distal protection using Filtrap (Nipro Corporation, Tokyo, Japan), which significantly reduced the volume of the neoatherosclerosis. However, subsequent ELCA on the highest setting (fluence, 60 mJ/mm2 and frequency, 40 pulse/s) led to a filter no-reflow phenomenon, although OCT revealed a further effective vaporization of the neoatherosclerosis and an apparent reduction of soft tissue compatible with the thrombus. After removing the embolic protection device, drug-coated balloon angioplasty provided optimal results without coronary flow disturbance. Discussion: Excimer laser coronary atherectomy reduces soft plaque and thrombus burden, which can reduce the occurrence of distal embolization in select cases. In the case of this patient, procedure-related distal embolization may have been induced by the heightened photomechanical effects resulting from the use of the highest setting in ELCA under increased intracoronary arterial pressure caused by continuous saline injection during ELCA. Concomitant distal protection during ELCA may be more feasible for preventing coronary flow disturbance in patients with a large amount of neoatherosclerosis.

Sarcomatoid mesothelioma diagnosed in a patient with mesothelioma in situ: a case report on morphologic differences after 9-month interval with details analysis of cytology in early-stage mesothelioma.

BACKGROUND: Overlapping morphological features of mesothelial cells have been rendered it difficult to distinguish between reactive and malignant conditions. The development of methods based on detecting genomic abnormalities using immunohistochemistry and fluorescence in situ hybridization have contributed markedly to solving this problem. It is important to identify bland mesothelioma cells on cytological screening, perform efficient genomic-based testing, and diagnose mesothelioma, because the first clinical manifestation of pleural mesothelioma is pleural effusion, which is the first sample available for pathological diagnosis. However, certain diagnostic aspects remain challenging even for experts. CASE PRESENTATION: This report describes a case of a 72-year-old man with a history of asbestos exposure who presented with pleural effusion as the first symptom and was eventually diagnosed as mesothelioma. Mesothelioma was suspected owing to prominent cell-in-cell engulfment in mesothelial cells on the first cytological sample, and the diagnosis of mesothelioma in situ was confirmed by histology. Unexpectedly, sarcomatoid morphology of mesothelioma was found in the second pathology samples 9 months after the first pathological examination. Both the mesothelioma in situ and invasive lesion showed immunohistochemical loss of methylthioadenosine phosphorylase (MTAP) and homozygous deletion of cyclin dependent kinase inhibitor 2A (CDKN2A) on fluorescence in situ hybridization. The patient received medication therapy but died of disease progression 12 months after the diagnosis of the sarcomatoid morphology of mesothelioma. CONCLUSION: Our case suggests that cell-in-cell engulfment can be conspicuous in early-stage mesothelioma with inconspicuous nuclear atypia and few multinucleated cells. In addition, the presence of MTAP loss and CDKN2A homozygous deletion are suspected to be involved in early formation to invasive lesions and/or sarcomatoid morphology. We believe that it is important to consider genetic abnormalities when deciding on individual patient management. Furthermore, cases of mesothelioma, even those of an in situ lesion, with MTAP loss and/or CDKN2A deletion should be carefully followed up or subjected to early treatment.

A quantitative evaluation method utilizing the homology concept to assess the state of chromatin within the nucleus of lung cancer.

Homology is a mathematical tool to quantify "the contact degree", which can be expressed in terms of Betti numbers. The Betti numbers used in this study consisted of two numbers, b0 (a zero-dimensional Betti number) and b1 (a one-dimensional Betti number). We developed a chromatin homology profile (CHP) method to quantify the chromatin contact degree based on this mathematical tool. Using the CHP method we analyzed the number of holes (surrounded areas = b1 value) formed by the chromatin contact and calculated the maximum value of b1 (b1MAX), the value of b1 exceeding 5 for the first time or Homology Value (HV), and the chromatin density (b1MAX/ns2). We attempted to detect differences in chromatin patterns and differentiate histological types of lung cancer from respiratory cytology using these three features. The HV of cancer cells was significantly lower than that of non-cancerous cells. Furthermore, b1MAX and b1MAX/ns2 showed significant differences between small cell and non-small cell carcinomas and between adenocarcinomas and squamous cell carcinomas, respectively. We quantitatively analyzed the chromatin patterns using homology and showed that the CHP method may be a useful tool for differentiating histological types of lung cancer in respiratory cytology.

Rapidly progressive infective endocarditis after MitraClip therapy: A rare complication of transcatheter edge-to-edge mitral valve repair.

Infective endocarditis (IE) is a rare, life-threatening complication of MitraClip (Abbott, Abbott Park, IL, USA) therapy. We report a case of an 84-year-old male who underwent transcatheter edge-to-edge mitral valve (MV) repair using MitraClip (Abbott, Abbott Park, IL, USA) 4 weeks prior for ventricular functional mitral regurgitation (MR) and returned with unstable hemodynamics and high-grade fever. Transthoracic echocardiography (TTE) on emergency admission showed thickening of the anterior mitral leaflet (AML) without apparent MR deterioration. TTE and transesophageal echocardiography (TEE) performed the next day showed severe MR due to rapidly progressing AML degeneration with aneurysmal formation. During the TEE examination, exacerbated heart failure due to severe MR caused cardiogenic shock and subsequent ventricular fibrillation, necessitating emergency extracorporeal cardiopulmonary resuscitation. Considering the positive findings of methicillin-resistant Staphylococcus aureus (MRSA) in blood cultures and degenerative MV findings, MitraClip-related IE was diagnosed; finally, MV replacement was performed. Retrospective consideration suggested that the potential causes of this MitraClip-related IE were valve injuries caused by multiple full-close procedures and insufficient prophylaxis for preoperatively detected MRSA. MitraClip-related IE has destructive characteristics that necessitate surgical intervention despite high risks; therefore, we should prevent procedure-related MV injuries and implement preoperative infection precautions to prevent catastrophic complications, particularly in patients with preoperative nasal MRSA-positive findings. Learning objectives: MitraClip-related infective endocarditis (IE) is a rare but fatal condition. IE caused by methicillin-resistant Staphylococcus aureus (MRSA), in particular, has an inferior prognosis with high mortality rates due to its destructive nature. Therefore, interventionalists should consider preventive strategies to avoid procedure-related valve injuries and adequately prepare for prophylaxis of patients who are carriers of MRSA to prevent MitraClip-related IE caused by MRSA.

Usefulness of NF2 hemizygous loss detected by fluorescence in situ hybridization in diagnosing pleural mesothelioma in tissue and cytology material: A multi-institutional study.

OBJECTIVES: BAP1, CDKN2A, and NF2 are the most frequently altered genes in pleural mesotheliomas (PM). Discriminating PM from benign mesothelial proliferation (BMP) is sometimes challenging; it is well established that BAP1 loss, determined by immunohistochemistry (IHC), and CDKN2A homozygous deletion (HD), determined by fluorescence in situ hybridization (FISH), are useful. However, data regarding the diagnostic utility of NF2 FISH in PM is limited. Thus, we performed a multi-institutional study examining the utility of NF2 alterations determined by FISH for diagnosing PM in combination with BAP1 loss and CDKN2A HD. MATERIALS AND METHODS: Multi-institutional PM cases, including 106 surgical and 107 cell block samples as well as 37 tissue cases of benign mesothelial proliferation (BMP) and 31 cell block cases with reactive mesothelial cells (RMC), were collected and analyzed using IHC for BAP1 and FISH for CDKN2A and NF2. RESULTS: In PM, NF2 FISH revealed hemizygous loss (HL) in 54.7% of tissue cases (TC) and 49.5% of cell block cases (CBC), with about 90% of HL being monosomy. CDKN2A HD or BAP1 loss were detected in 75.5%/65.4% TC or 63.6%/60% CBC, respectively. BMP or RMC showed no BAP1 loss, CDKN2A HD, or NF2 HL. For discriminating PM from BMP, a combination of BAP1 loss, CDKN2A HD, and NF2 HL yielded enhanced sensitivity of 98.1% TC/94.4% CBC. BAP1 loss, CDKN2A HD, or NF2 HL were observed in 69%, 70%, or 58% of epithelioid PM, but in 9%, 91%, or 27% of sarcomatoid PM, respectively. Histotype, histological gradings, and CDKN2A deletion status showed significant differences in overall survival, while BAP1 loss and NF2 HL did not. CONCLUSION: NF2 HL, consisting predominantly of monosomy, can be detected by FISH in both TC and CBC of PM, and is effective for distinguishing PM from BMP, especially when combined with BAP1 loss and CDKN2A HD.

Detection of lymph node metastasis in non-small cell lung cancer using the new system of one-step nucleic acid amplification assay.

INTRODUCTION: The prognosis of non-small cell lung cancer greatly depends on the presence of lymph node metastasis, which limits the need for surgery and adjuvant therapy for advanced cancer. One-step nucleic acid amplification of cytokeratin19 (CK19) mRNA was used to detect lymph node metastasis. Automated Gene Amplification Detector RD-200 and the LYNOAMP CK19 gene amplification reagent as components of the new one-step nucleic acid amplification system, which has increased gene amplification efficiency by improving the reagent composition, have shorter preprocessing and measurement times than conventional systems. We aimed to compare the clinical performance of the new system with that of histopathology and the conventional system. MATERIALS AND METHODS: 199 lymph nodes from 58 non-small cell lung cancer patients who underwent lymph node dissection were examined intraoperatively using the new system, conventional system, and histopathology. RESULTS: Lymph node metastasis was diagnosed in 32, 42, and 44 patients using histopathological analysis, the new system, and the conventional system, respectively. Compared with histopathological analysis, the concordance rate, sensitivity, specificity, positive predictive value, and negative predictive value of the new system were 92.0%, 90.6%, 92.2%, 69.0%, and 98.1%, respectively, and compared with the conventional system, the values were 95.0%, 86.4%, 97.4%, 90.5%, and 96.2%, respectively. CONCLUSION: The clinical performance of the new one-step nucleic acid amplification system in detecting lymph node metastasis of lung cancer is comparable to that of histopathology and the conventional system; its performance was sufficient for determining the appropriate clinical treatment. The new rapid system can be effectively utilized during lung cancer treatment intraoperatively and postoperatively.

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and the Japanese Society of Clinical Cytology: An Extensive Study Containing More Benign Lesions.

INTRODUCTION: The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the "neoplastic, benign neoplasm, and low-grade carcinoma" category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system. METHODS: We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system. RESULTS: The interobserver agreement was moderate in the JLCS-JSCC (k = 0.499) and PSC (k = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into "negative" or "atypical" by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as "suspicious" or "malignant" by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system. CONCLUSIONS: The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice.

Fluorescence in situ hybridization detection of chromosome 22 monosomy in pleural effusion cytology for the diagnosis of mesothelioma.

BACKGROUND: Malignant pleural mesothelioma (MPM) is characterized by mutations in several genes, including cyclin-dependent kinase-inhibitor 2A/p16 in the 9p21 locus, BRCA1-associated protein 1 (BAP1), and neurofibromatosis type 2 (NF2) in the 22q12 locus. Recent studies indicate that fluorescence in situ hybridization (FISH) detects hemizygous loss of NF2 in tissue specimens of MPM. The authors investigated whether NF2 FISH, either alone or in combination with other diagnostic assays (9p21 FISH, methylthioadenosine phosphorylase [MTAP] immunohistochemistry [IHC], and BAP1 IHC), effectively distinguishes MPM cells from reactive mesothelial cells (RMCs) in cell blocks prepared from pleural effusions. METHODS: FISH assays were used to examine the deletion status of NF2 and 9p21, and IHC was used to determine the expression of MTAP and BAP1 in cell blocks from 54 cases with MPM and 18 cases with RMCs. RESULTS: Hemizygous NF2 loss (chromosome 22 monosomy or hemizygous deletion) showed 51.9% sensitivity (48.1% for chromosome 22 monosomy and 3.7% for hemizygous deletion) and 100% specificity in differentiating MPM cells from RMCs. Combinations of NF2 FISH, 9p21 FISH, and BAP1 IHC assays yielded greater sensitivity (98.1%) than any assay alone (9p21 FISH, 61.1%; MTAP IHC, 52.8%; or BAP1 IHC, 60.4%). The level of hemizygous NF2 loss in cell blocks positively correlated with that in corresponding tissues. Furthermore, to overcome cytologic specimen-specific challenges, FISH combined with cytokeratin AE1/AE3 immunofluorescence was necessary in 25.9% of MPM cases for FISH assessment of predominantly scattered MPM cells. CONCLUSIONS: NF2 FISH alone or in combination with other diagnostic assays effectively differentiates MPM cells from RMCs in cell blocks prepared from pleural effusions.