title: A prospective study on the efficacy of two-dose influenza vaccinations in cancer patients receiving chemotherapy.
abstract: OBJECTIVE
  Cancer patients receiving chemotherapy are at risk of acquiring influenza infections. Two-dose vaccination is a proposed strategy for increasing vaccination efficacy; however, this has yet to be confirmed in this population. The purpose of this study was to clarify the efficacy and safety of this strategy.
  
  
  METHODS
  We conducted a multicentre prospective study on a two-dose vaccination regimen in cancer patients receiving chemotherapy. Second vaccinations were performed in patients who did not respond to all three viral strains after the first vaccination. Serum haemagglutination inhibition titres were measured to determine the patients' immunological response, 2 weeks prior to the first vaccination, 3-5 weeks after each vaccination, and at the end of the influenza season.
  
  
  RESULTS
  We enrolled 109 patients, including 70 with solid tumours, 36 with haematological malignancies, and 3 with both cancer types. Among the total patients, the proportion of patients with protective titres against the three viral strains increased significantly from 3 to 27% (P < 0.01) following vaccination. Among the 79 patients who received a second vaccination, the proportion of those with protective titres against the individual strains increased by 10% (H1N1), 8% (H3N2), and 3% (B) compared with after the first vaccination. Serious adverse events were not observed.
  
  
  CONCLUSIONS
  We recommend influenza vaccinations for cancer patients, including those receiving chemotherapy. Also, the additional benefit of the second vaccination may be limited.
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Yukinari
authors.initials: Y
authors.lastname: Sanada
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture kyakushi@med.kobe-u.ac.jp.
authors.forename: Kimikazu
authors.initials: K
authors.lastname: Yakushijin
authors.affiliation: Hyogo Prefectural AWAJI Medical Center, Sumoto City, Hyogo Prefecture.
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Nomura
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Naoko
authors.initials: N
authors.lastname: Chayahara
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Masanori
authors.initials: M
authors.lastname: Toyoda
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Minami
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Naomi
authors.initials: N
authors.lastname: Kiyota
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Toru
authors.initials: T
authors.lastname: Mukohara
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Kawamoto
authors.affiliation: Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, Kobe City, Hyogo Prefecture, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Ito
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuoka
authors.affiliation: Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe City, Hyogo Prefecture.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Minami
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy*; D011446:Prospective Studies; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D000069283:Rituximab / Q000627:therapeutic use; D014611:Vaccination; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D000970:Antineoplastic Agents; D007166:Immunosuppressive Agents; D007252:Influenza Vaccines; D047428:Protein Kinase Inhibitors; D000069283:Rituximab
keywords: cancer patients; chemotherapy; haemagglutination inhibition titre; influenza vaccination; prospective study; two-dose vaccination