Abstract

Background: Ovarian metastasis from non-small cell lung cancer (NSCLC) is an extremely rare clinical presentation, particularly in cases harboring ALK rearrangements. To date, most reports have been limited to isolated case studies. Differentiating ovarian metastasis from primary ovarian cancer remains diagnostically challenging. Accurate diagnosis and appropriate treatment in such cases provide valuable insights and contribute meaningfully to clinical practice.

Case report: A 32-year-old previously healthy female presented with lower abdominal pain. Clinical examination and imaging revealed bilateral ovarian masses, a right supraclavicular lymph node, and atypical pulmonary lesions. The initial diagnosis was suspected primary ovarian cancer with metastases to cervical lymph nodes and lungs. Biopsy of the cervical lymph node demonstrated adenocarcinoma of pulmonary origin, confirmed by positive immunohistochemical staining for TTF-1 and Napsin A. Next-generation sequencing (NGS) identified an ALK gene rearrangement. The final diagnosis was primary lung adenocarcinoma (right lung) TxN3M1 with metastases to the brain, liver, and pancreas, bone, follow up for ovarian metastases; however, concurrent primary ovarian cancer could not be entirely excluded. The patient was treated with Alectinib and showed a partial response, with near-complete resolution of lesions after 9 months. At 18 months, disease progression was noted in the brain, which was subsequently well controlled with Lorlatinib.

Conclusions: This case represents one of the few documented instances of ovarian metastasis from ALK-rearranged non-small cell lung cancer. Despite an aggressive initial clinical presentation, the patient demonstrated a remarkable response to targeted therapy. This case highlights the critical importance of accurate diagnosis and underscores the efficacy of ALK inhibitors, even in rare metastatic patterns.