False Positive F-18 FDG PET/CT in Neck and Mediastinum Lymph Nodes Due to Anthracosis in a Buccal Cancer Patient

Comparison of the 68 Ga-FAPI Versus 18 F-FDG in Gastric Adenocarcinoma and Anthracosis-Associated Lymph Nodes: FAPI Unmasking False-Negatives and False-Positives

ABSTRACT

A 73-year-old woman with poorly differentiated gastric adenocarcinoma was referred to 18 F-FDG PET/CT for evaluation of the disease. FDG PET/CT showed intense uptake in the disseminated lymph nodes. However, there was no uptake in the primary tumoral lesion. Subsequently, 68 Ga-FAPI-04 PET/CT was performed with the decision of the tumor board and demonstrated intense uptake in the tumoral lesion. However, there was low or no uptake in disseminated lymph nodes. Tru-cut biopsy results revealed that all the lymph nodes were associated with anthracosis.

Silicosis as an unusual cause of symptomatic cervical adenopathy

A case of symptomatic cervical adenopathy is reported as a presentation of silicosis. Silicosis is one of the most important occupational health diseases worldwide caused by the inhalation of airborne silica particles. The presence of thoracic adenopathies is a common clinical feature of silicosis, cervical silicotic adenopathies on the other hand are rare and unknown to most clinicians and can therefore lead to a differential diagnostic problem. Awareness of the clinical, radiological, and histological features is key for the diagnosis.

How I treat refractory/relapsed diffuse large B-cell lymphomas with CD19-directed chimeric antigen receptor T cells

Chimeric antigen receptor (CAR) T cells targeting CD19 represent a promising salvage immunotherapy for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL), offering ~40% of long-term responses. In everyday clinical practice, haematologists involved in CAR T cell treatment of patients with R/R DLBCL have to deal with diagnostically complex cases and difficult therapeutic choices. The availability of novel immunotherapeutic agents for R/R DLBCL and recent advances in understanding CAR T-cell failure mechanisms demand a rational approach to identify the best choice for bridging therapy and managing post-CAR T-cell therapy relapses. Moreover, positron emission tomography/computerised tomography may result in false-positive interpretation, highlighting the importance of post-treatment biopsy. In this review, we discuss all above issues, presenting four instructive cases, with the aim to provide criteria and new perspectives for CAR T-cell treatment of DLBCL.

Cytologic Evaluation of Positron Emission Tomography-Computed Tomography-Positive Lymph Nodes Sampled by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: Experience at a Large Cancer Center

CONTEXT.—

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is routinely used to evaluate mediastinal lymph nodes (LNs), especially for cancer staging. There are limited large studies evaluating the cytologic, radiologic, and clinical features of ¹⁸F-fluorodeoxy glucose positron emission tomography-computed tomography-positive (PET-CT+) LNs.

OBJECTIVE.—

To compare cytologic, radiologic, and clinical features of PET-CT+, cytology-malignant (PET-CT+/Cyto+) and PET-CT+, cytology-benign (PET-CT+/Cyto-) LNs.

DESIGN.—

The pathology database was searched for cases of mediastinal LNs obtained by EBUS-TBNA from January 1, 2015 to December 31, 2015. The cytologic, radiologic, and clinical features were collected for all PET-CT+ LNs.

RESULTS.—

Of 2267 mediastinal LNs obtained by EBUS-TBNA during this period, 577 LNs met the criteria. Of the latter, 263 (46%) were PET-CT+/Cyto+ and 314 (54%) were PET-CT+/Cyto-. All of the patients with PET-CT+/Cyto+ results had a prior or concurrent diagnosis of malignancy as compared to 89% of patients with PET-CT+/Cyto- results. Of the 224 patients with PET-CT+/Cyto+ LNs, 177 (79%) had metastases from lung primary, 43 (19%) had metastases from nonlung primaries, and 7 (3%) had lymphoma. Average LN size was larger in the PET-CT+/Cyto+ group than in the PET-CT+/Cyto- group (14.6 mm versus 9.58 mm), and mean standardized uptake value in PET-CT+/Cyto+ LNs was higher than that of PET-CT+/Cyto- LNs (10.05 versus 5.99). Significant cytologic findings in PET-CT+/Cyto- cases were necrosis and granulomatous inflammation, including 3 cases with fungal organisms.

CONCLUSIONS.—

PET-CT positivity alone was nonspecific for malignancy and insufficient to guide management of patients with mediastinal adenopathy, but specificity could be improved when combined with LN size and standardized uptake value.

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.

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

Microscopic anthracotic pigment (MAP) is frequently observed in endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) specimen in non-small cell lung cancer, but its clinical interpretation is not well-known. The aim of this study was to evaluate the clinical implication of MAP in mediastinal staging of non-small cell lung cancer. From May 2010 to July 2011, consecutive potentially operable non-small cell lung cancer patients who underwent EBUS-TBNA for mediastinal staging were recruited. Of the total 133 patients, 102 (76.7%) were male patients. Median age was 68 yr. Total 279 mediastinal lymph nodes were sampled by EBUS-TBNA; station 4R (100, 35.8%) and station 7 (86, 30.8%) were the most common sites. Malignant lymph nodes were 100 (35.8%). MAP was observed in 61 (21.7%) lymph nodes, and among them only 3 were malignant lymph nodes (P < 0.001). The lymph nodes with MAP were smaller (9.0 vs 10.8 mm, P = 0.001) and showed low standard uptake values on FDG-PET (4.4 vs 4.7, P = 0.256). In multivariate analysis, MAP was negatively associated with malignant lymph node (adjusted OR, 0.12; 95% CI, 0.03-0.42; P < 0.001). In potentially operable non-small cell lung cancer patients, MAP in endobronchial ultrasound-guided transbronchial needle aspiration specimens is strongly associated with benign mediastinal and hilar lymph nodes.

Primary nodal anthracosis identified by EBUS-TBNA as a cause of FDG PET/CT positive mediastinal lymphadenopathy

Isolated mediastinal lymphadenopathy can result from a number of potentially serious aetiologies. Traditionally those presenting with mediastinal lymphadenopathy would undergo mediastinoscopy to elucidate a final diagnosis or receive empirical treatment. There is now increased utilization of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), in this setting.

Five cases of mediastinal lymphadenopathy are presented here in which lymph node anthracosis was identified as the primary diagnosis using EBUS-TBNA. They were female, non-smokers presenting with non-specific symptoms, who retrospectively reported cooking over wood fires. Four were from South Asia. Three were investigated by F-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scanning and increased signal was identified in the anthracotic nodes sampled.

With expansion of PET/CT and EBUS-TBNA services it is likely that primary nodal anthracosis will be encountered more frequently and should be considered in the differential diagnosis of those with PET/CT positive lymphadenopathy. It may mimic pathologies including tuberculosis and malignancy, thus accurate sampling and follow-up are essential.