ALK+ NSCLC Presents as Rare Mediastinal Mass in Case Study

By: Lisa Astor
Posted: Friday, June 13, 2025

Intrathoracic malignancies should be considered for lung cancer diagnoses, the authors of a case report published in JCO Precision Oncology concluded. The report illustrated a case of a young, non-smoking woman who presented with a large mediastinal mass that was discovered to be ALK-rearranged non–small cell lung cancer (NSCLC).  

NSCLC rarely presents as a mediastinal mass, so when the patient presented with a cough and the tumor was found, she was initially diagnosed with embryonal carcinoma and treated with chemotherapy. The tumor continued to grow and so the patient was referred for additional testing, upon which the EML4-ALK fusion was identified, and the diagnosis was changed to poorly differentiated adenocarcinoma of the lung. The patient was then treated with alectinib 600 mg twice daily. After approximately 3.5 years of continuous alectinib treatment, a lesion was found in the right occipital lobe of the brain. The patient was treated with stereotactic radiosurgery and then was able to continue on alectinib. The patient is still alive 6 years after her diagnosis.  

Corresponding author Urs M. Weber, MD, of the University of Colorado Anschutz Medical Campus, and the other authors, noted that, “This case...also illustrates the importance of early molecular testing, which not only has treatment implications but can also help to make a diagnosis, particularly when histologic assessment and IHC are not conclusive.” 

Disclosure: For full disclosures of the study authors, visit ascopubs.org.  

JCO Precision Oncology

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