Increases in serum CYFRA21-1 concentration during successful treatment with crizotinib.
BACKGROUND
Increases in tumor marker concentrations usually suggest disease progression.


METHODS
We here describe on 3 patients with non-small cell lung cancer whose serum concentrations of CYFRA21-1 increased in spite of successful treatment with crizotinib. Discontinuation of crizotinib resulted in a rapid decrease in serum CYFRA21-1 concentrations in all cases. In 1 patient with progressive disease, in spite of increasing the dose of crizotinib, CYFRA21-1 concentrations decreased.


CONCLUSIONS
Crizotinib can induce increases in CYFRA21-1 concentration without disease progression. Pulmonologists and oncologists should be aware of this novel phenomenon, and focus on interpretation of CYFRA21-1 concentrations in monitoring tumor response to crizotinib treatment.
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Nobuhiro
N
Kanaji
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Akira
A
Tadokoro
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Naoki
N
Watanabe
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Takuya
T
Inoue
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Tomoya
T
Ishii
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Hiroaki
H
Dobashi
Department of Internal Medicine, Division of Hematology, Rheumatology and Respiratory Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Shuji
S
Bandoh
D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy*; D000077547:Crizotinib; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053539:Keratin-19 / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D011720:Pyrazoles / Q000627:therapeutic use*; D011725:Pyridines / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D053539:Keratin-19; D047428:Protein Kinase Inhibitors; D011720:Pyrazoles; D011725:Pyridines; C102012:antigen CYFRA21.1; D000077547:Crizotinib