Simultaneous Use of Endobronchial and Endoscopic Ultrasound Guidance as Primary Tools in the Diagnosis of Malignant Pleural Mesothelioma

Abstract

Malignant pleural mesothelioma (MPM) is related to exposure to asbestos. It is insidious in nature and is generally diagnosed at an advanced stage. MPM is aggressive and portends a poor prognosis. Definitive diagnosis is usually established by obtaining pathological samples of the pleura by medical or surgical thoracoscopy. However, these procedures are invasive and carry a risk of seeding of biopsy sites with tumors. We herein report an infrequently encountered case of simultaneous use of endobronchial ultrasound and endoscopic ultrasound-guided biopsy of malignant pleural mesothelioma in a 48-year-old female patient.

Keywords: endobronchial ultrasound; endoscopic ultrasound; malignant pleural mesothelioma; pleural biopsy; pleural effusion.

Figure 1. Computed tomography of the chest showing the right internal thoracic lymph node (indicated by blue arrow). The lymph node measured 1.8 x 1.3 cm

Figure 2. Computed tomography of the chest showing a 1.3 cm-large right internal mammary lymph node (indicated by arrow).

Figure 3. Computed tomography of the chest with intravenous contrast showing a hypoattenuating mass encasing the superior vena cava. The mass is indicated by the arrow.

Figure 4. Positron emission tomography/ computed tomography of the chest showing a hypermetabolic mediastinal lymph node indicated by the blue arrow. It also showed moderate volume right pleural effusion.

Figure 5. Positron emission tomography/ computed tomography of the abdomen showing a hyper-metabolic para-esophageal lymph node indicated by the arrow.

Figure 6. Endoscopic ultrasound image showing an enlarged para-esophageal lymph node.

Figure 7. Endoscopic ultrasound image showing needle biopsy of the para-esophageal lymph node (indicated by the arrow).

Figure 8. Metastatic malignant mesothelioma illustrated by fine needle aspiration (FNA) and biopsy of the paraesophageal lymph node.

FNA smears (A, Diff Quik stain, 400X; B, Papanicolaou stain, 400X) show cohesive clusters of epithelioid cells with monotonous round/ovoid nuclei, fine granular chromatin, small nucleoli, and a moderate amount of cytoplasm. The tumor cells have a hobnailing appearance. The concurrent biopsy (C, hematoxylin, and eosin stain, 200X) displays fibrous tissue and detached clusters of tumor cells with distinct cell borders and hobnailing arrangement. Immunohistochemical stain for calretinin (D, 400X) demonstrates both nuclear and cytoplasmic staining in the tumor cells.