case_images: PMC11249445_01
case_images: a CT scan of main lung lesion at time of diagnosis measuring 3.3 x 2.5 cm. b CT scan of main lung lesion after 3 cycles of treatment demonstrating stable disease. c CT scan of main lung lesion at the end of chemo-immunotherapy treatment demonstrating decrease in tumor size (2.2 x 1.8 cm).
case_images: cro-2024-0017-0001-539650_F01.jpg
case_images: PMC11249445_05_cro-2024-0017-0001-539650_F01.jpg
case_images: F1
case_images: After completion of three cycles, interval imaging showed the left upper lobe lesion to be stable with no new concerning areas of disease (shown in Fig. 1b). Repeat imaging 5 months after starting treatment showed decrease in size of the left upper lobe lesion (2.2 x 1.8 cm) and stable size in the other mass, indicating a partial response (shown in Fig. 1c).
case_images: Poorly differentiated adenocarcinoma. On lower power (a), this area of the biopsy demonstrates solid and glandular architecture. On higher power (b), the tumor is composed of large eosinophilic cells high nuclear to cytoplasm ratio. The cytoplasm is solid and eosinophilic, while the nuclei are large, hyperchromatic, and some contain prominent nucleoli. Moderate nuclear pleomorphism and scattered apoptotic and mitotic activity can be noted. A representative high-power field of a different biopsy area (c) demonstrates a more solid morphology. By IHC, lesional cells are positive for a cytokeratin cocktail AE1/3 and CAM5.2 (d), glypican-3 (e), SALL-4 (f), and HepPar-1 (g) and focally positive for glutamine synthetase (h) and arginase-1 (i). Unabsorbed CEA (j) and CD10 (k) show equivocal canalicular staining patterns.
case_images: cro-2024-0017-0001-539650_F02.jpg
case_images: PMC11249445_01_cro-2024-0017-0001-539650_F02.jpg
case_images: F2
case_images: To establish the diagnosis, an endobronchial ultrasound-guided biopsy of the larger left upper lobe mass was performed, which proved a metastatic poorly differentiated adenocarcinoma IHC positive for cytokeratin markers (AE1/3 and CAM5.2), glypican-3, SALL-4, and HepPar-1 and focal positivity for glutamine synthetase and arginase-1 (Fig. 2). The tumor was negative for OCT3/4, napsin, TTF-1, cytokeratin-7 and 20, p40, GATA3, CDX2, RCC, PSA, and NKX3.1.
case_images: PMC11249445_02
case_images: PMC11249445_03
case_images: PMC11249445_04
case_images: PMC11249445_05
case_images: a CT scan of main lung lesion at time of diagnosis measuring 3.3 x 2.5 cm. b CT scan of main lung lesion after 3 cycles of treatment demonstrating stable disease. c CT scan of main lung lesion at the end of chemo-immunotherapy treatment demonstrating decrease in tumor size (2.2 x 1.8 cm).
case_images: cro-2024-0017-0001-539650_F01.jpg
case_images: PMC11249445_05_cro-2024-0017-0001-539650_F01.jpg
case_images: F1
case_images: After completion of three cycles, interval imaging showed the left upper lobe lesion to be stable with no new concerning areas of disease (shown in Fig. 1b). Repeat imaging 5 months after starting treatment showed decrease in size of the left upper lobe lesion (2.2 x 1.8 cm) and stable size in the other mass, indicating a partial response (shown in Fig. 1c).