Avoiding underdiagnosis, overdiagnosis, and misdiagnosis of lung carcinoma

Toluidine Blue Stain as a Rapid Onsite Tool for Preliminary Diagnosis in Imprint Smears of Bronchoscopic Biopsy: A Cytohistopathological Correlation

Introduction  Lung cancer is currently the most common cause of cancer-related mortality, with 11.4% of cancers and 18% of cancer-related deaths worldwide whereas Indian figures are 6.9 and 9.3%, respectively. Hence, the need for early diagnosis. Bronchial biopsy has the highest sensitivity among all the samples that can be obtained by bronchoscopic techniques in case of endobronchial lesions. Imprint cytology has emerged as an important cytological method. Toluidine blue has been studied for its use as rapid onsite stain for cytological evaluation on various samples of cytology in different anatomic sites. This has helped in quick and less expensive, preliminary reporting. Objectives  This article aims to assess the efficacy of onsite toluidine blue stain on imprint smears of bronchoscopic biopsies to diagnose malignancy in suspected cases of lung carcinoma. Study Type  Prospective study on accuracy of a diagnostic test. Materials and Methods  A total of 100 cases of bronchoscopy were included in the study. The patients were clinico-radiologically suspected to have brochogenic carcinoma and all of them were subjected to biopsy. Imprint smears were prepared from the bronchoscopy biopsy specimens. Smears were stained onsite with toluidine blue stain, and histopathology sections were stained with hematoxylin and eosin, also confirmed by immunohistochemistry. Results  Sensitivity and specificity of onsite toluidine blue stain for malignancy reporting were 97.9 and 80%, respectively, when compared to histopathology as standard. Conclusion  Toluidine blue can be used as an onsite staining method on imprint smears of bronchoscopic biopsy for preliminary detection of lung malignancy.

Epigenetic imprinting alterations as effective diagnostic biomarkers for early-stage lung cancer and small pulmonary nodules

Background

Early lung cancer detection remains a clinical challenge for standard diagnostic biopsies due to insufficient tumor morphological evidence. As epigenetic alterations precede morphological changes, expression alterations of certain imprinted genes could serve as actionable diagnostic biomarkers for malignant lung lesions.

Results

Using the previously established quantitative chromogenic imprinted gene in situ hybridization (QCIGISH) method, elevated aberrant allelic expression of imprinted genes GNAS, GRB10, SNRPN and HM13 was observed in lung cancers over benign lesions and normal controls, which were pathologically confirmed among histologically stained normal, paracancerous and malignant tissue sections. Based on the differential imprinting signatures, a diagnostic grading model was built on 246 formalin-fixed and paraffin-embedded (FFPE) surgically resected lung tissue specimens, tested against 30 lung cytology and small biopsy specimens, and blindly validated in an independent cohort of 155 patients. The QCIGISH diagnostic model demonstrated 99.1% sensitivity (95% CI 97.5–100.0%) and 92.1% specificity (95% CI 83.5–100.0%) in the blinded validation set. Of particular importance, QCIGISH achieved 97.1% sensitivity (95% CI 91.6–100.0%) for carcinoma in situ to stage IB cancers with 100% sensitivity and 91.7% specificity (95% CI 76.0–100.0%) noted for pulmonary nodules with diameters ≤ 2 cm.

Conclusions

Our findings demonstrated the diagnostic value of epigenetic imprinting alterations as highly accurate translational biomarkers for a more definitive diagnosis of suspicious lung lesions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01203-5.

Identification of transcriptional subtypes in lung adenocarcinoma and squamous cell carcinoma through integrative analysis of microarray and RNA sequencing data

Classification of tumors into subtypes can inform personalized approaches to treatment including the choice of targeted therapies. The two most common lung cancer histological subtypes, lung adenocarcinoma and lung squamous cell carcinoma, have been previously divided into transcriptional subtypes using microarray data, and corresponding signatures were subsequently used to classify RNA-seq data. Cross-platform unsupervised classification facilitates the identification of robust transcriptional subtypes by combining vast amounts of publicly available microarray and RNA-seq data. However, cross-platform classification is challenging because of intrinsic differences in data generated using the two gene expression profiling technologies. In this report, we show that robust gene expression subtypes can be identified in integrated data representing over 3500 normal and tumor lung samples profiled using two widely used platforms, Affymetrix HG-U133 Plus 2.0 Array and Illumina HiSeq RNA sequencing. We tested and analyzed consensus clustering for 384 combinations of data processing methods. The agreement between subtypes identified in single-platform and cross-platform normalized data was then evaluated using a variety of statistics. Results show that unsupervised learning can be achieved with combined microarray and RNA-seq data using selected preprocessing, cross-platform normalization, and unsupervised feature selection methods. Our analysis confirmed three lung adenocarcinoma transcriptional subtypes, but only two consistent subtypes in squamous cell carcinoma, as opposed to four subtypes previously identified. Further analysis showed that tumor subtypes were associated with distinct patterns of genomic alterations in genes coding for therapeutic targets. Importantly, by integrating quantitative proteomics data, we were able to identify tumor subtype biomarkers that effectively classify samples on the basis of both gene and protein expression. This study provides the basis for further integrative data analysis across gene and protein expression profiling platforms.

Pulmonary carcinomas arising in association with scar: Cytomorphologic features in histologically confirmed cases

BACKGROUND

Lung carcinoma arising in association with scar tissue is a well-reported but much debated phenomenon. Scar tissue complicates imaging and pathologic tumor measurement for cancer staging. To the best of our knowledge, the cytological findings in lung scar carcinoma (LSC) have not been described in the literature. Therefore, the aim of this study was to characterize the findings in fine-needle aspirations (FNA) from histologically confirmed LSCs.

METHODS

LSCs were identified on retrospective search. Cases with preoperative FNA material were reviewed, including non-scar cases that were used for comparison. The clinical and histopathology findings were recorded.

RESULTS

Twenty-seven cases associated with scar tissue had material for review and 35 cases not associated with scar tissue were used for comparison. The proportion of fibrosis in resection specimens ranged from 10% to 80%. Five (19%) FNA cases were hypocellular. There was no statistically significant difference between the scar and non-scar groups in terms of overall cellularity and diagnostic categories (P = .113 and P = .17, respectively). There was correlation between cytology and dominant pattern on histology in 19 (79%) adenocarcinoma cases. Spindle cells and fibrous or fibroelastotic fragments were present in 22 (81%) cases.

CONCLUSION

This is the first study describing the cytology associated with LSCs. The presence of fibrosis did not adversely impact cellularity, which is likely due to multiple excursions and selective microdissection of tumor cells by the FNA needle. The cytomorphological and histological patterns correlated in most cases. FNA is able to provide a preoperative diagnosis of carcinoma despite the presence of fibrosis.

Pulmonary Cystic Disease and Its Mimics

Cystic diseases of the lung encompass a fairly broad variety of different diseases with causes including genetic abnormalities, smoking-related problems, developmental disorders, malignant neoplasms, and inflammatory processes. In addition, there are several diagnoses that closely resemble cystic lung disease, including cavitary diseases, cystic bronchiectasis, emphysema, and cystic changes in fibrosing interstitial lung disease. This article provides a review of cystic lung disease and its gross and histologic mimics.

Evaluation of Imprint Smears of Bronchoscopic Biopsy in Lung Tumors: A Cytohistological Correlation

Background:

There are several methods for obtaining samples in patients of lung tumors, of which bronchoscopic biopsy is the most common. In most of Indian scenario, however, histopathology diagnosis is time taking.

Aims and Objectives:

To evaluate imprint cytology as a tool for rapid diagnosis of lung carcinoma and its histopathological correlation.

Study Type:

Prospective study on accuracy of a diagnostic test.

Materials and Methods:

A total of 175 cases were included in the study, and all of them were subjected to brochoscopic biopsy. Imprint smears were prepared from all the bronchoscopy specimens obtained from 175 cases. Imprint smears were stained with Leishman-Giemsa cocktail and Pap stain, and histopathology sections were stained with hematoxlin and eosin. Histopathological findings were confirmed by immunohistochemistry.

Results:

Sensitivity and specificity of imprint cytology was 84.9% and 72.4%, respectively when compared to histopathology as standard.

Conclusion:

Imprint cytology can be used as a preliminary tool for diagnosis in lung tumor bronchoscopic biopsies.

An investigation into false-negative transthoracic fine needle aspiration and core biopsy specimens

Transthoracic fine needle aspiration (TFNA)/core needle biopsy (CNB) under computed tomography (CT) guidance has proved useful in the assessment of pulmonary nodules. We sought to determine the TFNA false-negative (FN) rate at our institution and identify potential causes of FN diagnoses. Medical records were reviewed from 1,043 consecutive patients who underwent CT-guided TFNA with or without CNB of lung nodules over a 5-year time period (2003-2007). Thirty-seven FN cases of "negative" TFNA/CNB with malignant outcome were identified with 36 cases available for review, of which 35 had a corresponding CNB. Cases were reviewed independently (blinded to original diagnosis) by three pathologists with 15 age- and sex-matched positive and negative controls. Diagnosis (i.e., nondiagnostic, negative or positive for malignancy, atypical or suspicious) and qualitative assessments were recorded. Consensus diagnosis was suspicious or positive in 10 (28%) of 36 TFNA cases and suspicious in 1 (3%) of 35 CNB cases, indicating potential interpretive errors. Of the 11 interpretive errors (including both suspicious and positive cases), 8 were adenocarcinomas, 1 squamous cell carcinoma, 1 metastatic renal cell carcinoma, and 1 lymphoma. The remaining 25 FN cases (69.4%) were considered sampling errors and consisted of 7 adenocarcinomas, 3 nonsmall cell carcinomas, 3 lymphomas, 2 squamous cell carcinomas, and 2 renal cell carcinomas. Interpretive and sampling error cases were more likely to abut the pleura, while histopathologically, they tended to be necrotic and air-dried. The overall FN rate in this patient cohort is 3.5% (1.1% interpretive and 2.4% sampling errors).

Pre- and postoperative self-reported cognitive effectiveness and worry in patients with suspected lung malignancy

PURPOSE/OBJECTIVES

To examine perceived cognitive effectiveness and worry in individuals with suspected lung cancer before and after surgical resection and to determine any differences between individuals with and without a postoperative diagnosis of lung cancer.

DESIGN

A repeated measures longitudinal design.

SETTING

A comprehensive cancer center and a Veterans Administration medical center in the midwestern United States.

SAMPLE

15 men and 8 women aged 37-82 years (X = 61.4, SD = 10.7) with suspected lung cancer.

METHODS

Descriptive statistics were used to characterize data. Paired t tests and nonparametric correlation analysis were used to determine relationships among the main study variables.

MAIN RESEARCH VARIABLES

Perceived effectiveness in cognitive function as well as general and cancer-specific worry.

FINDINGS

Patients diagnosed with lung cancer were significantly older. Patients self-reported lowered perceived effectiveness in daily activities that require directed attention both pre- and postoperatively. Patients with nonmalignant postoperative reports had higher general worry at each time point, which was significant following surgery.

CONCLUSIONS

A diagnosis of suspected lung cancer may contribute to compromised perceived effectiveness in cognitive function. Nonmalignant pathology following a diagnosis of suspected lung cancer may be associated with continued worry.

IMPLICATIONS FOR NURSING

Nursing assessment and interventions aimed at supporting effective cognitive function and modifying worry for patients with suspected lung cancer are essential to optimize adjustment.

KNOWLEDGE TRANSLATION

Suspected lung cancer imposes high demands on cognitive and emotional function. Oncology nurses are in key positions to support patients during and following the diagnostic workup for lung cancer. Younger patients with nonmalignant postoperative reports may need continued follow-up.

Type I insulin-like growth factor receptor induces pulmonary tumorigenesis

Despite the type I insulin-like growth factor receptor (IGF-IR) being highly expressed in more than 80% of human lung tumors, a transgenic model of IGF-IR overexpression in the lung has not been created. We produced two novel transgenic mouse models in which IGF-IR is overexpressed in either lung type II alveolar cells (surfactant protein C [SPC]-IGFIR) or Clara cells (CCSP-IGFIR) in a doxycycline-inducible manner. Overexpression of IGF-IR in either cell type caused multifocal adenomatous alveolar hyperplasia with papillary and solid adenomas. These tumors expressed thyroid transcription factor 1 and Kruppel-like factor 5 in most tumor cells. Similar to our previous work with lung tumors that developed in the mouse mammary tumor virus-IGF-II transgenic mice, the lung tumors that develop in the SPC-IGFIR and CCSP-IGFIR transgenic mice expressed high levels of the cyclic adenosine monophosphate response element binding protein that was localized primarily to the nucleus. Although elevated IGF-IR expression can initiate lung tumor development, tumors can become independent of IGF-IR signaling as IGF-IR down-regulation in established tumors produced tumor regression in some, but not all, of the tumors. These findings implicate IGF-IR as an important initiator of lung tumorigenesis and suggest that the SPC-IGFIR and CCSP-IGFIR transgenic mice can be used to further our understanding of human lung cancer and the role IGF-IR plays in this disease.