case_images: PMC11828711_01
case_images: Axial and sagittal computed tomography images at the time of presentation of the large anterior mediastinal mass with complete left lung atelectasis and associated large left-sided pleural effusion
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case_images: PMC11828711_01_cureus-0017-00000077507-i01.jpg
case_images: FIG1
case_images: A computed tomography (CT) of the chest and neck revealed a conglomerate of anterior mediastinal and left lower cervical lymph nodes measuring up to 18x8.7 cm, along with complete left lung collapse with invasion from the mass and large left pleural effusion (Figure 1).
case_images: Diffuse large B-cell lymphoma mediastinal tissue membrane staining for BCL-2 (BCL-2/peroxidase immunostaining)
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case_images: PMC11828711_01_cureus-0017-00000077507-i02.jpg
case_images: FIG2
case_images: A CT-guided fine needle biopsy of the mediastinal mass was diagnostic of PMBCL with immunohistochemistry being positive for CD20, PAX5, BCL2, BCL6, MUM1, and C-MYC (Figure 2).
case_images: Anteroposterior and lateral chest X-ray images of the chest following drainage of the pleural effusion with persistent left lung atelectasis and large ex vacuo pneumothorax
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case_images: PMC11828711_01_cureus-0017-00000077507-i03.jpg
case_images: FIG3
case_images: Following drainage of the pleural effusion, a chest x-ray revealed a significant ex vacuo pneumothorax and sustained entire left lung atelectasis (Figure 3).
case_images: Anteroposterior and lateral chest X-ray four months after initiating treatment with improved aeration of the left lower lobe and lingula. Persistent atelectasis of the left upper lobe is noted.
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case_images: PMC11828711_01_cureus-0017-00000077507-i04.jpg
case_images: FIG4
case_images: Four months after chemotherapy, imaging revealed a reduction in the mass's size with improved aeration of the left lung (Figure 4).
case_images: Axial computed tomography of the chest after completion of treatment with re-expansion of the left upper lobe
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case_images: PMC11828711_01_cureus-0017-00000077507-i05.jpg
case_images: FIG5
case_images: The patient responded favorably to the six cycles of chemotherapy and achieved complete remission as evidenced by CT scans showing ongoing improvement in the size of the mass and expansion of the left lung (Figure 5).