An online quiz uncovers limitations of morphology in equivocal lung cytology

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and Japanese Society of Clinical Cytology: An Interobserver Reproducibility Study and Risk of Malignancy Evaluation on Cytology Specimens

INTRODUCTION

The classification of lung carcinoma is based on small biopsies and/or cytology in 80% of patients with non-small cell carcinoma. However, there is no widely accepted classification system for respiratory cytology. The Japan Lung Cancer Society (JLCS) and Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma with the following categories: (1) "negative for malignancy," (2) "atypical cells," (3) "suspicious for malignancy," and (4) "malignancy."

OBJECTIVE

The aim of this work was to perform an interobserver reproducibility study to confirm the utility of the four-tiered reporting system on respiratory cytological samples.

METHODS

We analyzed 90 cytological samples obtained with bronchoscopy. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the three-, four-, and five-tiered reporting systems.

RESULTS

The interobserver agreement was fair in the three- (κ = 0.50), four- (κ = 0.45), and five-tiered (κ = 0.45) reporting systems. However, the four-tiered reporting system provided more precise information than the three-tiered reporting system in patient management. The risk of malignancy in the four-tiered reporting system was also stratified well: 19.3% for "negative for malignancy," 45.6% for "atypical cells," 74.7% for "suspicious for malignancy," and 88.1% for "malignancy."

CONCLUSIONS

The reporting system proposed by the JLCS and JSCC was designed to enhance the communication between clinicians and pathologists and among different institutions. It is simple and applicable to cytological diagnosis of any respiratory diseases. We propose establishing an international classification for respiratory cytology, harmonizing the reporting systems proposed by different countries.

Respiratory Tract and Mediastinum

Normal cytology, abnormal and atypical cells, non-cellular components, and infectious cell changes are largely described together with benign, malignant, and neuroendocrine lesions regarding exfoliative and aspiration cytology of the lung. A separate section broadly addresses diagnostic findings and differential diagnoses in bronchoalveolar washings.

The section ‘Fine needle aspiration biopsy of mediastinal disorders’ covers in particular biopsy techniques, accuracy of liquid-based cytology, and the complex lesions of the thymus gland. Cytodiagnostic algorithms of the major benign and malignant pulmonary and mediastinal lesions and their respective differential diagnoses are additionally presented in synoptic setups.

International Internet-based assessment of observer variability for diagnostically challenging endometrial biopsies

CONTEXT

Endometrial carcinoma of endometrioid histology is frequently preceded by endometrial hyperplasia, from which localized, premalignant lesions called endometrial intraepithelial neoplasia (EIN) emerge. Diagnostic criteria for EIN have been developed by histopathologic correlation with clinical outcome, molecular changes, and objective computerized histomorphometry. However, several benign mimics of EIN continue to cause diagnostic confusion.

OBJECTIVE

To better understand the diagnostic pitfalls of EIN.

DESIGN

An online quiz of 18 endometrial biopsies considered difficult by a gynecologic pathologist was constructed. Each case contained clinical history and at least 2 microscopic images. Answer choices included the following: (1) EIN, (2) polyp, (3) benign endometrium (proliferative, secretory, disordered, tubal metaplasia, and lower uterine segment), and (4) adenocarcinoma. Online tutorials were offered at the start, and the authors' diagnosis and clinical follow-up were provided at the end.

RESULTS

The quiz was completed by 78 participants from 13 countries. Agreement with the authors ranged from 17% to 100% (mean, 55%). For analysis, polyp and benign responses were grouped. The mean percentage of agreement was highest in cases of polyp with no special features (88%), tubal metaplasia (87%), and secretory change (75%). Poorer agreement was seen with cases containing mucinous metaplasia (38%), extensive morular metaplasia (28%), and EIN arising in a polyp (53%). The mean percentage of agreement for EIN without these features was 63%.

CONCLUSIONS

Although the reproducibility of EIN criteria was good, a subset of biopsies with morular metaplasia and EIN in polyps was problematic and likely required consensus review.

Equivocal cytology in lung cancer diagnosis: improvement of diagnostic accuracy using adjuvant multicolor FISH, DNA-image cytometry, and quantitative promoter hypermethylation analysis

BACKGROUND

Sometimes, cytological lung cancer diagnosis is challenging because equivocal diagnoses are common. To enhance diagnostic accuracy, fluorescent in situ hybridization (FISH), DNA-image cytometry, and quantitative promoter hypermethylation analysis have been proposed as adjuncts.

METHODS

Bronchial washings and/or brushings or transbronchial fine-needle aspiration biopsies were prospectively collected from patients who were clinically suspected of having lung carcinoma. After routine cytological diagnosis, 70 consecutive specimens, each cytologically diagnosed as negative, equivocal, or positive for cancer cells, were investigated with adjuvant methods. Suspicious areas on the smears were restained with the LAVysion multicolor FISH probe set (Abbott Molecular, Des Plaines, Illinois) or according to the Feulgen Staining Method for DNA-image cytometry analysis. DNA was extracted from residual liquid material, and frequencies of aberrant methylation of APC, p16(INK4A) , and RASSF1A gene promoters were determined with quantitative methylation-specific polymerase chain reaction (QMSP) after bisulfite conversion. Clinical and histological follow-up according to a reference standard, defined in advance, were available for 198 of 210 patients.

RESULTS

In the whole cohort, cytology, FISH, DNA-image cytometry, and QMSP achieved sensitivities of 83.7%, 78%, 79%, and 49.6%, respectively (specificities of 69.8%, 98.2%, 98.2%, and 98.4%, respectively). Subsequent to cytologically equivocal diagnoses, FISH, DNA-image cytometry, and QMSP definitely identified malignancy in 79%, 83%, and 49%, respectively. With QMSP, 4 of 22 cancer patients with cytologically negative diagnoses were correctly identified.

CONCLUSIONS

Thus, adjuvant FISH or DNA-image cytometry in cytologically equivocal diagnoses improves diagnostic accuracy at comparable rates. Adjuvant QMSP in cytologically negative cases with persistent suspicion of lung cancer would enhance sensitivity.

Zytologie im Internet

Computer-based learning (E-learning) is of increasing importance for the education of students and professionals. Various publicly accessible online courses for cytologists now exist and some of these are presented in this paper. For the learning platform Patho-Basiliensis (http://www.unibas.ch/patho/) we have developed several learning materials: a database of 726 cytology images, a cytopathology course to teach the basics of cytopathology, and a game testing histologic-cytologic correlation. Tests on lung and urinary cytology were attended by 383 international participants. The virtual microscopy technology will revolutionize telecytology and cytology education.