Organizing pneumonia in ALK⁺ non-small cell lung cancer treated with ceritinib: a case report

INTRODUCTION: Anaplastic lymphoma kinase (ALK) inhibitors have been approved for non-small cell lung cancer (NSCLC) patients with ALK-rearrangement. Ceritinib, a clinically approved ALK inhibitor, is associated with some adverse reactions, including organizing pneumonia (OP). However, few cases of ceritinib-induced OP have been reported to date. PATIENT CONCERNS: A 59-year-old female patient with ALK + lung adenocarcinoma presented with paroxysmal cough lasting 3 months. Antibiotic therapy was not effective, and blood and sputum cultures were negative. DIAGNOSIS: A computed tomography (CT)-guided biopsy of the left upper lung was performed and hematoxylin–eosin staining was consistent with OP. The diagnosis of ceritinib-induced OP was considered based on these results. INTERVENTIONS: Ceritinib was then stopped, and the patient was treated with methylprednisolone (40 mg ivgtt qd) for one week. The dose was lowered to 32 mg po qd with regular follow-up. Later, the patient switched to another ALK inhibitor, ensartinib, for treatment, and the steroid was discontinued after two months. OUTCOMES: A Chest CT scan after one week of treatment showed progressive disappearance of lung lesions, and the patient was discharged on oral methylprednisolone (32 mg qd) for two weeks after which the dose was reduced gradually. CONCLUSION: OP should be considered when new lesions appear in the lungs of lung cancer patients, and distinguished from infectious pneumonia, metastasis, or cancer progression. In this respect, pathological biopsy plays an important role in diagnosis. In our case, discontinuation of ceritinib and regular steroid administration were effective.