Clinical implication of microscopic anthracotic pigment in mediastinal staging of non-small cell lung cancer by endobronchial ultrasound-guided transbronchial needle aspiration

The Curious Case of the Black Buboes

Anthracosis is an environmental lung disease caused by carbon deposition and pigmentation in the airways. However, in rare instances, it can also have systemic involvement. We present a patient with B-symptoms and diffuse lymphadenopathy who was diagnosed with the infrequently described nodal anthracosis. A 64-year-old Vietnamese gentleman with a 50-pack-year smoking history who was recently diagnosed with prostate cancer post-radical prostatectomy and awaiting radiation therapy presented with generalized weakness, low-grade fever, night sweats, and unquantifiable weight loss for a month. He was hemodynamically stable, and examination revealed bilateral inguinal and axillary lymphadenopathy. Computed tomography (CT) showed diffuse lymphadenopathy involving the mediastinum, hilar, axillary, mesenteric, retroperitoneal, and bilateral iliac chains with multiple diffuse pulmonary nodules. Laboratories disclosed anemia, thrombocytopenia, elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), albumin-globulin (A-G) reversal, and sterile blood cultures. The disseminated intravascular coagulation panel was negative with normal fibrinogen and mildly elevated D-dimer. Autoimmune workup, including antinuclear antibody (ANA), was negative. Infectious workup included Babesia, Ehrlichia, Anaplasma, Lyme serology, QuantiFERON-TB Gold, HIV, and hepatitis panel, and all were negative. He was managed with broad-spectrum antibiotics, which were discontinued after a negative infectious workup. He also complained of a new-onset holocranial headache with no features of meningitis; an MRI with contrast revealed focal occipital leptomeningeal involvement and cerebral edema with occipital lymphadenopathy. A lumbar puncture was planned but deferred at the patient's request. An excisional lymph node biopsy of the left axillary lymph node revealed reactive follicular hyperplasia with no evidence of malignancy, with flow cytometry negative for any evidence of B- or T-cell malignancies. He continued to have persistent low-grade fevers. A bone marrow biopsy showed 70% cellularity with paratrabecular interstitial lymphoid aggregates composed of both T and B cells, which was nonspecific, and flow cytometry could not be done due to dry tap. An F-18-fluorodeoxyglucose positron emission tomography (FDG PET) scan showed extensive hypermetabolic disease both above and below the diaphragm with bulky mediastinal adenopathy and splenomegaly. Subsequently, he underwent a mediastinoscopy and biopsy of the mediastinal lymph nodes, which demonstrated reactive hyperplasia and abundant anthracitic pigment on microscopic examination, consistent with the diagnosis of nodal anthracosis. He was managed conservatively, discharged, and found to have spontaneously resolved symptoms at a six-week follow-up. Nodal anthracosis with PET-positive mediastinal and hilar lymphadenopathy is a rare presentation of anthracosis that mimics infectious conditions, granulomatous diseases, and malignancies. The pigment deposition can cause persistent inflammatory activity and should be considered an infrequent but important explanation of lymphadenopathy in patients without known biomass exposure.

The Differentiation of Metastatic Mediastinal Lymph Nodes From Benign Hypermetabolic Lesions

Background

Anthracosis may cause a positron emission tomography/computed tomography (PET/CT) false positivity in mediastinal and hilar lymph nodes. We aimed to evaluate the radiological features and the maximum standardized uptake values (SUVmax) of the mediastinal lymph nodes with anthracosis or squamous cell lung cancer metastasized.

Methodology

Patients diagnosed with anthracosis or squamous cell lung cancer with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) between January 1, 2015, and November 15, 2020, in a tertiary hospital were enrolled. The squamous cell subtype of lung cancer was selected due to its association with tobacco use, biomass, and air pollution. Anthracosis may occur due to the same etiologic reasons.

Results

A total of 190 patients met the study enrollment criteria, of which 86 were diagnosed with anthracosis and 33 with squamous cell lung cancer lymph metastasis. Median values for short axis, long axis, SUVmax, shape features, and presence of calcification were found significantly different between the groups. In receiver operating characteristic (ROC) analysis, the SUVmax cut-off value was calculated as 6.61. With this cutoff value, the negative predictive value (NPV) was 92.5% and the positive predictive value (PPV) was 54% for differentiating anthracosis and malignant lymph nodes metastasis.

Conclusions

We conclude that the evaluation of the shape and metabolic activities of the anthracotic lymph nodes detected by PET/CT together with EBUS-TBNA granted a more accurate staging of the patients and more cancer patients will benefit from surgical treatment.

A retrospective observational study of benign anthracotic lymphadenitis and its association with PET avid lymph nodes in patients undergoing cancer evaluation

Background

Accurate staging of newly diagnosed or recurrent malignancy is essential for effective treatment. An important first step in staging involves the use of PET/CT to identify areas of FDG avidity. PET/CT however has limitations, including false positive FDG uptake from benign causes. In this paper we characterize an uncommon yet clinically important cause of false positive PET/CTs, that of benign anthracotic lymphadenitis (BAL). We examine the clinical, radiographic and histologic characteristics of BAL in patients referred for endobronchial ultrasound (EBUS) guided biopsies and discuss its context in relation to existing literature.

Methods

We performed a retrospective observational case series of 20 patients who were referred for EBUS guided biopsies of PET positive mediastinal and hilar lymph nodes during the work-up or treatment of suspected malignancy.

Results

To be included, all patients received PET imaging as well as an EBUS guided biopsy of FDG avid lymph nodes which demonstrated anthracotic pigment as the only histologic abnormality. The key findings were that 90% of patients in this cohort were born outside of the US, 90% had bilateral FDG avid lymph nodes with an average standardized uptake value (SUV) of 7.9±2.2. Most patients, based on their history, had a likely exposure to biomass fuel or urban pollution.

Conclusions

BAL may be an underrecognized cause for PET positive lymph nodes in patients undergoing work-up for malignancy. These findings support the importance of sampling mediastinal and hilar lymph nodes even when SUVs are highly suggestive of malignancy.

The value of endobronchial ultrasound-guided transbronchial needle aspiration, 18-fluorodeoxyglucose positron emission tomography/computed tomography, and ultrasonography imaging techniques in the diagnosis of mediastinal and/or hilar malignant, anthracotic, and other benign lymph nodes

INTRODUCTION

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a simple, reliable, minimally invasive and effective procedure. However, a surgical technique may be required, if the results are negative. Therefore, there is a need for new studies to increase the diagnostic value of EBUS-TBNA and provide additional information to guide the biopsy in performing the procedure. Here, we aimed to investigate the diagnostic value of EBUS-TBNA and 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosis of hilar and/or mediastinal lymph nodes (LNs). It was also aimed to determine the contributions of real-time ultrasonography (USG) images of LNs to distinguishing between the malignant and benign LNs during EBUS-TBNA, and in the diagnosis of anthracotic LNs.

MATERIAL AND METHOD

In the retrospective study including 545 patients, 1068 LNs were sampled by EBUS-TBNA between January 2015 and February 2020. EBUS-TBNA, 18-FDG PET/CT and images of USG were investigated in the diagnosis of mediastinal and/or hilar malignant, anthracotic and other benign LNs.

RESULTS

The sensitivity, specificity, positive predictive value and negative predictive value of EBUS-TBNA were found as 79.5, 98.1, 89.5, and 91.7%, respectively. Mean maximum standardized uptake value (SUVmax) values of 18F-FDG PET/CT were 6.31±4.3 in anthracotic LNs and 5.07 ± 2.53 in reactive LNs. Also, mean SUVmax of malignant LNs was 11.02 ± 7.30 and significantly higher than that of benign LNs. In differentiation of malignant-benign tumors, considering the cut off value of 18F-FDG PET/CT SUVmax as 2.72, the sensitivity and specificity was 99.3 and 11.7%, but given the cut off value as 6.48, the sensitivity, specificity, positive predictive value and negative predictive value was found as 76.5, 64, 20.49, and 78.38% for benign LNs, respectively. Compared LNs as to internal structure and contour features, malignant LNs had most often irregular contours and heterogeneous density. Anthracotic, reactive and other benign LNs were most frequently observed as regular contours and homogeneous density. The difference between malignant and benign LNs was significant.

CONCLUSION

EBUS can contribute to the differential diagnosis of malignant, anthracotic and other benign LNs. Such contributions can guide clinician bronchoscopists during EBUS-TBNA. The triple modality of EBUS-TBNA, 18FDG PET/CT, and USG may increase the diagnostic value in hilar and mediastinal lymphadenopathies.

Scary black nodes

Anthracosis is associated with smoking, air pollution, tuberculosis infection, and exposure to biomass. Anthracosis commonly involves bronchial trees and rarely lymph nodes. We report an unusual case of a 44-year-old female presented with painless supraclavicular swelling for 1 month. A fine-needle aspiration cytology examination was done from the swelling. The smears were markedly cellular and showed the presence of sheets, clusters, and singly scattered round to oval cells with mild anisonucleosis, fine to coarse chromatin, few with tiny nucleoli, and cytoplasm containing abundant black coarse pigment. At many places, the fibroblasts and lymphocytes were admixed with histiocytes containing pigment. The cell block made showed cell morphology similar to that described above for fine-needle aspiration smears. The immunohistochemistry on the cell block and special stains helped to ascertain the nature of pigment and cell type. The final diagnosis of the anthracofibrosis lymph node was made. Due to its rarity, its awareness is a must; otherwise, it can be mistaken for metastatic deposits from malignant melanoma and can result in unnecessary surgical intervention and morbidity. However, it shall be considered one of the differential diagnoses of neck nodes in nonsmoker females with a history of domestic wood smoke exposure.

Concordance Between Rapid On-Site Evaluation and Final Cytologic Diagnosis in Patients Undergoing Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for Non-Small Cell Lung Cancer Staging

OBJECTIVES

In patients with lung cancer undergoing mediastinal staging through endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), decisions are based on rapid on-site evaluation (ROSE) findings. We aimed to analyze the concordance rate between ROSE diagnosis and final diagnosis.

METHODS

A prospective study was carried out in patients undergoing EBUS-TBNA for lung cancer staging. Diagnosis concordance was defined as cases where lymph nodes (LNs) presented the same diagnosis in ROSE and final diagnosis. Determinants of concordance were analyzed.

RESULTS

Sixty-four patients were included and 637 LNs sampled. ROSE diagnosis was concordant with final diagnosis in 612 (96.1%) LNs and nonconcordant in 25 (3.9%). Differences in the concordance rate were found between pathologists, ROSE diagnoses, presence of cell block, number of passes, and number of slides. The staging status was changed between ROSE and the final diagnosis in three (4.6%) patients.

CONCLUSIONS

ROSE diagnosis has a high concordance with the final diagnosis.

Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for Diagnosis and Staging of Lung Cancer

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS TBNA) is fundamental to the diagnosis of lung cancer, as many patients present with more advanced stages of lung cancer, with enlarged hilar and mediastinal lymph nodes. It also represents a way to sample pulmonary masses directly to make the diagnosis, whereby no other accessible tissue is present and the mass sits adjacent to a large central airway. Very importantly also, EBUS TBNA is the widely accepted first procedure in lung cancer staging. A combined procedure of EUS TBNA can be performed to improve diagnostic accuracy.

Needle-based Optical Coherence Tomography to Guide Transbronchial Lymph Node Biopsy

BACKGROUND

Transbronchial needle aspiration (TBNA), often used to sample lymph nodes for lung cancer staging, is subject to sampling error even when performed with endobronchial ultrasound. Optical coherence tomography (OCT) is a high-resolution imaging modality that rapidly generates helical cross-sectional images. We aim to determine if needle-based OCT can provide microstructural information in lymph nodes that may be used to guide TBNA, and improve sampling error.

METHODS

We performed ex vivo needle-based OCT on thoracic lymph nodes from patients with and without known lung cancer. OCT imaging features were compared against matched histology.

RESULTS

OCT imaging was performed in 26 thoracic lymph nodes, including 6 lymph nodes containing metastatic carcinoma. OCT visualized lymphoid follicles, adipose tissue, pigment-laden histiocytes, and blood vessels. OCT features of metastatic carcinoma were distinct from benign lymph nodes, with microarchitectural features that reflected the morphology of the carcinoma subtype. OCT was also able to distinguish lymph node from adjacent airway wall.

CONCLUSIONS

Our results demonstrate that OCT provides critical microstructural information that may be useful to guide TBNA lymph node sampling, as a complement to endobronchial ultrasound. In vivo studies are needed to further evaluate the clinical utility of OCT in thoracic lymph node assessment.

CT differentiation of enlarged mediastinal lymph node due to anthracosis from metastatic lymphadenopathy: a comparative study proven by endobronchial US-guided transbronchial needle aspiration

PURPOSE

Anthracosis often results in mediastinal nodal enlargement. The aim of this comparative study was to evaluate if it is possible to differentiate endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) proven anthracotic lymph nodes from malignant lymph node enlargement by means of multislice computed tomography (MSCT).

METHODS

We compared the MSCT findings of 89 enlarged lymph nodes due to anthracosis with 54 malignant lymph nodes (non-small cell lung cancer 75.9%, small cell lung cancer 18.5%, and non-Hodgkin lymphoma 5.6%). The lymph nodes were assessed for density (calcification, fat, and necrosis), shape (oval, round), contrast enhancement, and contour (sharp, ill-defined).

RESULTS

Malignant lymph nodes showed significantly greater axis diameters (P < 0.001). Both anthracotic and malignant nodes were most often oval (86.5% of all malignant nodes vs. 81.5% of all anthracotic nodes, P = 0.420) and showed confluence in a remarkable percentage (28.1% vs. 42.6%, P = 0.075). Anthracotic nodes showed calcifications more often (18% vs. 0%, P < 0.001). Malignant lymph nodes showed a significantly greater short and long axis diameter (P < 0.001), and they had a higher frequency of ill-defined contours (27.8% vs. 2.2%, P < 0.001) and contrast enhancement (27.8% vs. 5.6%, P < 0.001). Nodal necrosis, which appeared in one third of the malignant nodes, was not observed in anthracosis (35.2% vs. 0%, P < 0.001). Confluence of enlarged lymph nodes was seen in malignant lymph nodes (42.6%), as well as in lymph node enlargement due to anthracosis (28.1%, P = 0.075).

CONCLUSION

Our results show that there are significant differences in MSCT findings of malignant enlarged lymph nodes and benign lymph node enlargement due to anthracosis.

Black Endobronchial Ultrasound

The infrequent bronchoscopic finding of black airway pigmentation due to a variety of causes has been labeled as "Black Bronchoscopy." Black bronchioalveolar lavage has been sometimes described in tobacco, marijuana, and crack cocaine smokers. To add to this interesting panorama of bronchoscopic findings, we describe cases of black endobronchial ultrasound-guided transbronchial needle aspirates due to metastatic melanoma and anthracotic lymph nodes.

Adequacy Criteria of Rapid On-Site Evaluation for Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: A Simple Algorithm to Assess the Adequacy of ROSE

BACKGROUND

Rapid on-site evaluation (ROSE) for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been advocated to qualitatively diagnose biopsy samples. However, adequate ROSE criteria during EBUS-TBNA are unclear. The aim of this study was to determine adequacy criteria of ROSE in EBUS-TBNA samples and suggest an appropriate algorithm.

METHODS

Patients who underwent EBUS-TBNA for nodal evaluation between March and July 2013 at Seoul National University Hospital were included prospectively. The ROSE slides were reviewed independently by two pathologists, and the results were compared to the final pathologic results. Diagnostic yields, sensitivity, specificity, and accuracy were calculated in order to make nodal evaluations.

RESULTS

EBUS-TBNA was performed on 300 lymph nodes in 133 patients. Samples were nondiagnostic in 7.7%, 6.3%, and 1.7% of the cytologic, histologic, and overall pathologic results, respectively. On the ROSE slides, a large tissue core size (≥2 cm), microscopic anthracotic pigment (MAP), and increased lymphocyte density (LD; ≥40 cells/field [40×, mean of 10 fields]) were significantly associated with adequate final cytologic or histologic results. Malignant cells were not statistically associated with adequacy but were considered a parameter indicating an adequate diagnosis. Using four sequential criteria, tissue core size, the presence of malignant cell, MAP, and LD ≥40 cells/field, the sensitivity and accuracy rates of ROSE increased from 64.4% to 98.6% and from 64.7% to 97.3%, respectively.

CONCLUSIONS

A high adequacy rate of ROSE in EBUS-TBNA can be achieved by sequentially applying four criteria: tissue core size, malignant cells, MAP, and increased LD.

Diagnostic concordance rate between histologic and cytologic specimens of endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer: A single institution experience

BACKGROUND

The aspirates from endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) were examined using the tissue core and cytology. We assessed that the tissue core was a more reliable specimen and attempted to analyze how many discrepancies were found between the two specimens. We investigated diagnostic concordance rate between histology and cytology.

METHODS

From January 2011 to December 2011, a total of 267 consecutive patients with lung cancer, who underwent EBUS-TBNA, were included in this retrospective study.

RESULTS

Of the 267 lung cancer patients, 207 (77.5%) were men. The median age was 65 years old. The most common pathologic type was adenocarcinoma (120, 44.9%), followed by squamous cell carcinoma (79, 29.6%). Among the 267 patients, 579 mediastinal and hilar lymph nodes were punctured. The right lower paratracheal (204, 35.2%) and subcarinal (172, 29.7%) lymph nodes were the most common nodal stations. Among the 579 lymph nodes, malignant cells were observed in 267 (46.1%) nodes, in either the histologic, cytologic or both slides: 209 in both histology and cytology, 37 in histology only, and 21 in cytology only slides. The diagnostic concordance rate between the tissue core and cytology was 90.0% (95% confidence interval CI, 87.1-92.2) (κ = 0.79).

CONCLUSIONS

The diagnostic concordance rate between the histology and cytology of EBUS-TBNA in lung cancer was 90.0% (95% CI, 87.1-92.2) (κ = 0.79).