case_images: PMC11771589_01
case_images: (A and B) Histopathological images of lymph node biopsy samples from the patient; (C and D) ROS1 (1:400, GeneTech, Shanghai, Co., Ltd, China) immunohistochemistry staining.
case_images: medi-104-e41350-g001.jpg
case_images: PMC11771589_01_medi-104-e41350-g001.jpg
case_images: F1
case_images: The patient, a 37-year-old man with no history of smoking and no family history of cancers, was admitted to the hospital in March 2023 due to "cervical lymphadenopathy for 1 week." During hospitalization, a right cervical lymph node biopsy was obtained for postoperative pathology, which revealed metastatic adenocarcinoma of the lung (Fig. 1).
case_images: Timeline of clinical treatment course and radiologic feature.
case_images: medi-104-e41350-g002.jpg
case_images: PMC11771589_01_medi-104-e41350-g002.jpg
case_images: F2
case_images: The patient was diagnosed with right lower lung cancer (adenocarcinoma, T4N3M1c, stage IVB) (Fig. 2). After 1 month, the enlarged lymph nodes in the bilateral neck, mediastinal hilum, axilla, abdominal cavity, and retroperitoneal regions were significantly reduced, with no significant enlargement of the primary lesion in the right lower lung (Fig. 2). Trousseau syndrome (Fig. 2). This suggests widespread systemic progression of the tumor that signified the acquisition of crizotinib resistance.
case_images: Identification and verification of MYH9-ROS1 fusion. (A) DNA-NGS MYH9 (exon 37)-ROS1 (exon 35). (B) RNA-NGS MYH9-ROS1 (M36, R35) from the first biopsy in March, 2023. (C) RNA-NGS MYH9-ROS1 (M36, R35) from the second biopsy in August, 2023. (D) DNA-NGS TP53 co-mutation from the first biopsy in March, 2023. (E) Schematic of genomic rearrangement. (F) Fusion regions were visualized by the Integrative Genomic Viewer (IGV) software.
case_images: medi-104-e41350-g003.jpg
case_images: PMC11771589_01_medi-104-e41350-g003.jpg
case_images: F3
case_images: We compared the results of the 2 genetic tests and found that the results were consistent in the fusion patterns of MYH9 (exon 37)-ROS1 (exon 35) at the DNA level (Fig. 3), accompanied by a co-mutation of TP53 (Fig. 3). However, at the RNA level, the patient presented rare coexistence of short and long variants, MYH9 (exon 1-36)-ROS1 (exon 36-41) and MYH9 (exon 1-36)-ROS1 (exon 35-41), which were abbreviated as MYH9-ROS1 (M36, R36) and MYH9-ROS1 (M36, R35) (Fig. 3).