Although crizotinib shows marked antitumor activity in anaplastic lymphoma kinase (ALK) rearrangement-positive non-small-cell lung cancer (NSCLC) patients, all treated patients ultimately develop resistance to this drug. Isolated central nervous system failure without progression at extracranial sites is a common progression pattern in ALK rearrangement-positive NSCLC patients treated with crizotinib. Here, we report the success of crizotinib combined with whole-brain radiotherapy in an ALK rearrangement-positive NSCLC patient who developed leptomeningeal carcinomatosis and progression of multiple brain metastases. Additionally, we focused on the mechanism involved by examining the plasma and cerebrospinal fluid concentrations of crizotinib in the present case.

A 69-year-old man who had undergone chemoradiotherapy for advanced pulmonary adenocarcinoma had bilateral testicular and adrenal gland masses on a routine follow-up examination. We performed left orchiectomy, and the histopathological examination confirmed metastatic pulmonary adenocarcinoma involving the extracted testis. He was treated for disease progression with nivolumab after unsuccessful cytotoxic chemotherapy, which resulted in regression of recurrent adrenal and right testicular tumors. We reviewed the existing literature on metastatic testicular tumors and found that testicular metastasis from lung cancer is rare and poses a chemotherapeutic challenge. Based on our experience, immune checkpoint inhibitors seem to have good efficacy for treating testicular metastasis.

A 63-year-old man with pulmonary adenocarcinoma was treated with nivolumab. High fever developed within several hours after the first administration of nivolumab; subsequently, serum creatinine levels kept increasing daily. We diagnosed acute kidney injury (AKI) as an immune-related adverse event; the patient was initially treated with 50 mg prednisolone, and the dose was then tapered. Renal biopsy pathologically revealed tubulointerstitial inflammation with strong infiltration of only T cells that were CD3 + , CD4 + , and CD8 + . The infiltration of CD163 + M2 macrophage was also observed. AKI within 1 week after the administration of nivolumab seems to be rare; therefore, the present case provides important findings useful in daily clinical practice.