Reactive type II pneumocytes in bronchoalveolar lavage fluid from adult respiratory distress syndrome can be mistaken for cells of adenocarcinoma

Scrape cytology and radiological solid size correlation can be used in the intraoperative management of subsolid lung nodules

BACKGROUND

The term radiologic subsolid lung nodule (SLN) represents a heterogeneous group of non-neoplastic and neoplastic lesions. Intraoperative evaluation (IO) is often required to differentiate and diagnose. The current study aims to investigate the feasibility and reliability of scrape cytology (SC) and radiologic solid size correlation for the IO diagnosis of SLNs.

METHODS

Sixty-eight patients with SLN signs were eligible to take part in the study due to intraoperatively prepared SC slides. We managed to complete the blind radiologic solid size measurement and cytologic evaluation retrospectively. Cases were grouped into three categories based on their cytological features: Group-0 (Benign), Group-1 (mild atypical features), and Group-2 (severe atypical features/unequivocally carcinoma). IO diagnoses were given by combining the radiologic solid size and cytological findings.

RESULTS

Cytological features of Group-1 were observed in 100%, 93%, 32.5%, and 17% of the AIS, MIA, IA, and benign lesions, respectively. Cytological features of Group-2 were observed in 67.5%, and 7% of the IA and MIA, respectively. By combining cytology with radiologic solid size, 100%, 85%, 71%, and 83% of the AIS, IA, MIA, and benign lesions respectively were diagnosed correctly. Fifteen (15%) percent of the IA cases were underdiagnosed as MIA since their radiological solid sizes were less than 0.5 cm with cytological features of Group-1. Conversely, 29% of the MIA cases were overdiagnosed as IA since their radiological solid sizes were greater than 0.5 cm.

CONCLUSION

SLNs should be handled with caution in terms of IO management. SC and radiologic solid size correlation both provide a practical and tissue-protecting approach for the IO evaluation of SLNs, ensuring a high consistency between IO and definitive diagnosis.

"Napoleon Hat" Sign: A Distinctive Cytologic Clue to Reactive Pneumocytes

Various types of acute and subacute lung injury can cause severe reactive pneumocyte atypia, which may mimic malignant proliferations and present a major diagnostic pitfall. This particularly applies to cytologic preparations and frozen sections, where background inflammatory injury may be subtle or not apparent. Although several distinguishing morphologic features of reactive pneumocytes have been suggested, there is significant overlap with neoplastic proliferations. In this article, a highly distinctive but underrecognized feature of reactive pneumocytes is highlighted that can serve as a useful diagnostic clue. The feature refers to the distinctive pinched shape of reactive pneumocytes, for which the author has coined the term "Napoleon hat" sign to draw the analogy with the iconic headwear. The analogy vividly captures the distinctive shape of reactive pneumocytes, and can serve as a useful diagnostic and teaching tool in the interpretation of pulmonary specimens.

The relevance of bronchoalveolar lavage fluid analysis for lung cancer patients

Introduction: Lung cancer is a serious malignant disease with poor prognosis. The methods for improving early recognition and markers of predictive value are widely investigated. Bronchoalveolar lavage (BAL) is a valuable method of respiratory tract investigation. Currently, BAL is rarely used for tumor diagnosis, but for ruling out differential diagnosis, due to its poor sensitivity. The new indication for BAL fluid analysis is evaluation of local immune reaction in lung cancer patients and description of tumor microenvironment (TME). A literature search was performed in bibliography bases from the time of the introduction of BAL in the diagnosis of lung diseases. We analyzed our prior original studies with the bibliography.Area covered: The usefulness of BAL in the diagnosis of peripheral spread of malignant diseases and in the evaluation of TME in lung cancer, as well as a role of BAL in the diagnosis of checkpoint inhibitor pneumonitis is presented. Commentary concerning methodology of BALF analysis in lung cancer is included.Expert opinion: It seems that in the near future BAL will find an important place in the evaluation of lung cancer TME in two aspects. The first could be characteristic of immune reaction by analysis of immune cells and mediators and the second cancer molecular characteristic by free DNA and exosomes analysis.

The value of cell block based on fine needle aspiration for lung cancer diagnosis

BACKGROUND

Computed tomography (CT)-guided percutaneous lung fine needle aspiration (FNA) is a convenient method to obtain samples from pulmonary lesions. FNA has a lower rate of complications than the use of a core needle biopsy, but is more difficult for the diagnosis of cytological samples. We use cell block (CB) and immunocytochemistry (ICC) to improve the accuracy of cytological diagnoses based on CT-guided percutaneous lung FNA.

METHODS

We collected 526 cytological samples obtained using CT-guided percutaneous lung FNA at Shanghai Pulmonary Hospital from May 2015 to October 2015. CBs were created from these samples, and ICC was performed to help the further histological classification and confirmation of tumor as primary or metastatic. An automated Ventana ALK with clone D5F3 was used to identify ALK fusion protein.

RESULTS

After assessment of the CBs, 32 (6.08%) diagnoses of suspected malignancy were reduced to 10 (1.90%) such diagnoses (P<0.05), and 161 (30.61%) cases of non-small-cell lung carcinoma (NSCLC) were reduced to 33 (6.27%) cases (P<0.05) after their division into specific subtypes. We also diagnosed eight (1.52%, P<0.05) cases of metastatic carcinoma of the lung that were difficult to diagnose by cytological smear alone. Six (3.73%) of 161 NSCLC cases exhibited ALK rearrangement.

CONCLUSIONS

CB and ICC are useful for accurate cytological diagnosis using CT-guided percutaneous lung FNA. These approaches are valuable for providing individualized treatment and prognostic evaluations with minor complications.

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.

Bronchoalveolar lavage in idiopathic pulmonary fibrosis: what does it tell us?

Bronchoalveolar lavage (BAL) has only a limited role in diagnosis of idiopathic pulmonary fibrosis (IPF). A finding of raised neutrophils (>5%) and eosinophils (>2%) is characteristic but not diagnostic of IPF. BAL cell count does not clearly differentiate between fibrotic non-specific interstitial pneumonia and IPF either diagnostically or prognostically. BAL in IPF should be considered in all patients with suspected infection, malignancy or acute exacerbations. In such cases, it may be diagnostic. Because of few and conflicting results BAL fluid analysis has very little clinical relevance determining prognosis and response to treatment in IPF.

The use of genetic markers to identify lung cancer in fine needle aspiration samples

PURPOSE

We seek to establish a genetic test to identify lung cancer using cells obtained through computed tomography-guided fine needle aspiration (FNA).

EXPERIMENTAL DESIGN

We selected regions of frequent copy number gains in chromosomes 1q32, 3q26, 5p15, and 8q24 in non-small cell lung cancer and tested their ability to determine the neoplastic state of cells obtained by FNA using fluorescent in situ hybridization. Two sets of samples were included. The pilot set included six paraffin-embedded, noncancerous lung tissues and 33 formalin-fixed FNA specimens. These 39 samples were used to establish the optimal fixation and single scoring criteria for the samples. The test set included 40 FNA samples. The results of the genetic test were compared with the cytology, pathology, and clinical follow-up for each case to assess the sensitivity and specificity of the genetic test.

RESULTS

Nontumor lung tissues had < or= 4 signals per nucleus for all tested markers, whereas tumor samples had > or = 5 signals per nucleus in five or more cells for at least one marker. Among the 40 testing cases, 36 of 40 (90%) FNA samples were analyzable. Genetic analysis identified 15 cases as tumor and 21 cases as nontumor. Clinical and pathologic diagnoses confirmed the genetic test in 15 of 16 lung cancer cases regardless of tumor subtype, stage, or size and in 20 of 20 cases diagnosed as benign lung diseases.

CONCLUSIONS

A set of only four genetic markers can distinguish the neoplastic state of lung lesion using small samples obtained through computed tomography-guided FNA.

Effectiveness of sputum cytology using ThinPrep method for evaluation of lung cancer

Sputum cytology is a non-invasive test for evaluating lung cancer. But, its sensitivity is yet lower than other tests. ThinPrep (TP) is an automated cytopreparatory method that has mucolytic and hemolysing effects. We compared 955 sputum specimens that were prepared by both TP and conventional preparation (CP). The nuclear details were more preserved on the TP slides, while the obscuring materials were more eliminated on the TP slides as compared with the CP. The cytologic rates of TP were 2.7% unsatisfactory, 4.7% normal, 81.0% benign, 2.4% suspicious, and 9.1% malignancy. The rates of CP were 7.9% unsatisfactory, 1.6% normal, 84.8% benign, 1.8% suspicious, and 4.0% malignancy. The false negative rates, relative to the histologic data for 352 cases which the tissue diagnosis was available, were 49.6% (TP) and 69.4% (CP). Sputum cytology using the TP method improves the diagnostic accuracy for evaluating lung cancer by reducing the unsatisfactory and false-negative rates.

Exuberant type 2 pneumocyte hyperplasia associated with spontaneous pneumothorax: secondary reactive change mimicking adenocarcinoma

A wide variety of pulmonary and pleural histological changes is recognized in the setting of spontaneous pneumothorax. In this study, we describe a previously unreported lesion that was encountered in four males, 24-41 years of age. In addition to reactive eosinophilic pleuritis, subpleural emphysematous blebs, prominent eosinophilic exudate and lung atelectasis, the histology comprised exuberant type 2 pneumocyte hyperplasia, which was atypical enough to consider a diagnosis of adenocarcinoma in all four cases. Lung atelectasis and localized acute lung injury are factors likely responsible for this unusual histology, and along with the clinical history are important in recognizing the benign nature of this lesion. Awareness of this severe pneumocyte reaction in the setting of pneumothorax can help to prevent misdiagnosis as malignancy.

Multitarget Fluorescence In Situ Hybridization Elucidates Equivocal Lung Cytology

The category of equivocal respiratory cytology is a common diagnostic dilemma to both cytopathologists and clinicians. Chromosomal alterations are a hallmark of cancer but are rare or absent in benign conditions. The goal of this study was to test the ability of multitarget fluorescence in situ hybridization (FISH) for dissecting equivocal respiratory cytology into reactive and malignant categories. A consecutive series of 54 Papanicolaou-stained cytologic specimens of the lung was analyzed. The Papanicolaou-stained atypical cell groups were photographed, and the exact locations on the specimens were saved using automated stage and relocation software. The specimens were hybridized with a multitarget FISH probe that contains a mixture of fluorescent probes to the centromeric region of chromosome 6 and to the 5p15, 8q24 (site of the MYC gene) and 7p12 (site of the EGFR gene) loci. The hybridized atypical cells were selectively scored after relocation. A final diagnosis was available in 45 patients, revealing lung carcinoma in 55.5% (n = 25), no evidence of malignancy in 37.8% (n = 17), and pulmonary metastasis of another primary carcinoma in 6.7% (n = 3). FISH results were negative in all 17 patients with benign pulmonary disease and positive in 20 of the 25 patients (80%) with lung carcinoma (p < 0.0001). The sensitivity, specificity, and positive and negative predictive values for detection of malignancy were 79%, 100%, 100%, and 74%, respectively. These data suggest that multitarget FISH in conjunction with automated relocation is a powerful approach for the elucidation of equivocal lung cytology.

Diagnostic dilemmas in pulmonary cytology

BACKGROUND

Diagnostic difficulties in pulmonary cytology may be compounded by other medical problems, lack of pertinent information, and the presence of rare tumors. In the current study, the authors describe six cases of lower respiratory tract cytology that presented particular diagnostic challenges or pitfalls.

METHODS

Three lung fine-needle aspiration biopsies (FNAB) from three patients, four bronchoalveolar lavages from two patients, and one bronchial washing from one patient, each with histologic confirmation, were reviewed. Cytologic material included direct smears, ThinPrep slides, and cell blocks. Cytologic findings were compared with established cytologic criteria for each final diagnosis.

RESULTS

Two cases with Aspergillus infection that demonstrated reactive atypical cells were misinterpreted as squamous cell carcinoma and nonsmall cell carcinoma. Two cases diagnosed as significant atypia and negative, respectively, subsequently were found to show bronchioloalveolar carcinoma (as well as lymphangioleiomyomatosis, which was suspected clinically) and bronchogenic adenocarcinoma, respectively. One lung FNAB from a patient subsequently confirmed to have bronchiolitis obliterans-organizing pneumonia (BOOP) showed reactive pneumocytes that initially were misinterpreted as being suspicious for carcinoid. These reactive pneumocytes were identified histologically in the area of BOOP. The last case was an FNAB of a well differentiated fetal-type adenocarcinoma, an unusual variant of adenocarcinoma that to the authors' knowledge rarely is described in the cytology literature.

CONCLUSIONS

Cytomorphologic features of lower respiratory tract pathology combined with appropriate clinical information and diagnostic discretion usually allow accurate diagnoses and should decrease both false-positive and false-negative result rates. Clinical information and radiologic findings may be invaluable, but may not always parallel the cytologic diagnosis.

Detection of non-infectious conditions mimicking pneumonia in the intensive care setting: usefulness of bronchoalveolar fluid cytology

The present study investigated the usefulness of bronchoalveolar (BAL) fluid cytology in the identification of non-infectious pulmonary conditions in patients hospitalized in the intensive care unit (ICU) and suspected of pneumonia. A total of 182 BAL fluid samples obtained during a 27-month period from 130 ICU patients with suspected pneumonia were quantitatively cultured and investigated for opportunistic pathogens. Cytocentrifuged preparations stained with the May-Grünwald Giemsa and Perls's methods were reviewed. A non-infectious aetiology was considered when cultures yielded micro-organisms in quantities < 10(3) colony-forming units (CFU) per ml, in the absence of any other pathogen and in conjunction with one or more of the following cytological findings: > 20% haemosiderin macrophages, > 10% lymphocytes, the presence of activated lymphocytes, plasma cells, > 5% eosinophils, a preponderance of foamy macrophages, reactive type II pneumocytes or malignant cells. Patients' clinical records were reviewed to identify a clinical diagnosis for these episodes. In thirty-five (19.2%) BAL fluid samples from 26 patients, the cytological findings pointed to a non-infectious origin. An alternative diagnosis was ascertained in 20 of 26 patients. Diagnoses included: drug-induced pneumonitis (n = 7), aspiration of gastric contents (n = 2), pulmonary emboli (n = 3), adult respiratory distress syndrome (n = 4), lung contusion (n = 1), cardiogenic pulmonary oedema (n = 1), and carcinomatous lymphangitis (n = 2). The BAL fluid cytological findings were readily discernable and proved to be useful in the diagnostic work-up of samples obtained from ICU patients with suspected pneumonia.

BAL fluid cytology in the assessment of infectious lung disease

The need for rapid laboratory results has marked the application of bronchoalveolar lavage (BAL) fluid cytology as a valuable tool in the assessment of infectious lung conditions. The techniques of BAL fluid processing presented here can be performed in a microbiological laboratory. The diagnostic value of BAL fluid cytology for the prediction of ventilator-associated pneumonia is discussed.

Cytologic distinction between bronchioalveolar carcinoma and reactive/reparative respiratory epithelium: a cytomorphometric analysis

Cytologically, the distinction between bronchioalveolar carcinoma and reactive/reparative processes of respiratory epithelium can be difficult. Retrospectively, we have identified 11 consecutive cases of bronchioalveolar carcinoma from the cytology files of University Missouri-Kansas City/Truman Medical Center. On average, a combined 5.71 cytologic/histologic procedures were performed before reaching a definitive diagnosis for this group. An additional seven random cases of reactive/reparative respiratory cases of adult respiratory distress syndrome patients were used as a control. Cytomorphometric analysis was performed. The mean average nuclear diameter for the carcinoma group was 13.76 microns and for the reactive/reparative group was 13.29 microns. There was no statistical difference between the two groups (paired student t test, P > .05). It appears from our data that mean nuclear diameter is not a discriminator for the cytologic distinction between bronchioalveolar carcinoma and reactive/reparative respiratory epithelium and that the accepted cytologic parameters of for bronchioalveolar carcinoma are more valid.

Respiratory cytology: a review of non-neoplastic mimics of malignancy

Respiratory cytology has its share of pitfalls. Some, such as vegetable cell contaminants, pose problems for only inexperienced observers, while others, such as reactive bronchoalveolar cells from pneumonia, can lead even experienced cytopathologists to make a misdiagnosis of malignancy. This review illustrates and analyzes those benign conditions or entities known to mimic malignancy in exfoliative respiratory cytology and fine-needle aspiration biopsy of the lung. Entities are grouped by the type of malignancy they mimic, and guidelines are presented for avoiding specific pitfalls.

Pulmonary aspergillosis: an unusual cytologic presentation

Cytologic identification of Aspergillus is usually based on recognition of hyphal elements; conidia are rarely seen. We report a case of autopsy-proven pulmonary Aspergillosis which was studied antemortem by bronchoalveolar lavage. This mass arose in the clinical setting of chronic necrotizing pulmonary aspergillosis. The specimen contained numerous conidia, some of which exhibited germination. No hyphae were seen. This unusual cytologic expression of clinically significant fungal disease could be easily overlooked. Distinction of Aspergillus conidia from contaminating pollen is discussed.