title: Low-dose chemotherapy with leucovorin plus 5-fluorouracil for colorectal cancer can maintain host immunity.
abstract: BACKGROUND
  Anticancer drugs may frequently show host immunosuppression. Low-dose chemotherapy has been used for unresectable cancer as a tumor dormancy therapy, and it has been reported that the patients treated this way demonstrated favorable survival without toxicity. In this study, host immunity before and after a low-dose leucovorin plus 5-fluorouracil regimen (low-dose LV/5-FU) and S-1 plus irinotecan regimen (S-1/CPT-11) was compared to assess whether low-dose chemotherapy can maintain host immunity.
  
  
  METHODS
  Fourteen patients with recurrent or metastatic colorectal cancer underwent low-dose LV/5-FU, or S-1/CPT-11 treatment. The host immunity (cytokine production of the peripheral blood mono-nuclear cells (PBMC), serum soluble interleukin-2 receptor (sIL-2R) levels and phenotypic analyses of the PBMC) was measured before and after the first chemotherapy treatment.
  
  
  RESULTS
  An increase of sIL-2R and CD4+CD25+ T cells with S-1/CPT-11 treatment, and a decrease with low-dose LV/5-FU treatment were observed and these changes in the first course were significantly different (p =0.0722 for the slL-2R, p=0. 0187for the CD4+CD25+ T cells).
  
  
  CONCLUSIONS
  The current study indicated that there is no change or an improvement in host immunity with the low-dose LV/5-FU treatment as compared with the S-1/CPT-11 treatment. Low-dose LV/5-FU treatment should be considered for metastatic colorectal cancer in order to maintain a host immunity during chemotherapy.
authors.affiliation: Department of Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawaku, Tokyo 116-8567, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Kobayashi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yoshimatsu
authors.forename: Hajime
authors.initials: H
authors.lastname: Yokomizo
authors.forename: Takao
authors.initials: T
authors.lastname: Katsube
authors.forename: Kenji
authors.initials: K
authors.lastname: Ogawa
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D015704:CD4 Antigens / Q000097:blood; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015179:Colorectal Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D016207:Cytokines / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D005434:Flow Cytometry; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D053645:Interleukin-2 Receptor alpha Subunit / Q000097:blood; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010094:Oxonic Acid / Q000008:administration & dosage; D015375:Receptors, Interleukin-2 / Q000097:blood; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D005641:Tegafur / Q000008:administration & dosage; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015704:CD4 Antigens; D016207:Cytokines; D004338:Drug Combinations; D053645:Interleukin-2 Receptor alpha Subunit; D015375:Receptors, Interleukin-2; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D000077146:Irinotecan; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin