Aseptic inflammatory abscesses induced by crizotinib in a case report of ALK rearrangement lung adenocarcinoma.

Background: Adverse events induced by crizotinib treatment for lung adenocarcinoma are increasingly reported, with nephritic inflammatory abscesses accounting for only 4% of documented cases. To date, no reports exist regarding aseptic inflammatory abscesses of the back. Consequently, these conditions are often misdiagnosed clinically as cancer metastases or other infections, leading to delays in patient treatment. We report a case of a 34-year-old female patient who developed aseptic inflammatory abscesses in the back and nephritic inflammatory abscesses induced by crizotinib treatment for ALK-rearranged lung adenocarcinoma. The inflammatory abscesses improved after discontinuation of crizotinib. Subsequently, the patient received reduced-dose crizotinib therapy, with follow-up showing reduced complications and satisfactory tumor control. This report aims to fill gaps in the understanding of crizotinib-related adverse events, thereby enhancing the accuracy of diagnosis and management of these adverse events. Case report: A 34-year-old female patient with stage IVB right lung adenocarcinoma, accompanied by lymph node, liver, and bone metastases, received crizotinib therapy. After two years of crizotinib treatment, imaging studies revealed an aseptic inflammatory abscess in the back and left kidney. The lesions in the back and left kidney continued to enlarge despite incision and drainage, and the back abscess underwent surgical excision one month later. Pathology revealed aseptic inflammatory reaction without cancer cells. However, the postoperative back incision healed poorly with persistent purulent discharge, and the nephritic abscess continued to enlarge. Subsequently, based on radiographic and pathological findings suggestive of crizotinib-related adverse effects, the dosage of crizotinib was discontinued. The aseptic inflammatory abscess on the back rapidly improved after crizotinib discontinuation. The nephritic abscess, however, developed infection post-discontinuation and significantly reduced in size following antimicrobial therapy and drainage. Subsequently, crizotinib dosage reduction was implemented based on genetic testing. During follow-up, the inflammatory abscess continued to shrink without compromising tumor control efficacy. Conclusion: Early identification and diagnosis of crizotinib-associated aseptic inflammatory abscesses are critical. During treatment, reducing crizotinib dosage does not lead to recurrence of lung cancer while minimizing complications. The case underscores the necessity of integrating imaging and pathological features in the diagnostic process, alongside the need for personalized adjustments and development of treatment plans tailored to each patient.