title: Effect of neoadjuvant chemoradiation on tumor-infiltrating/associated lymphocytes in locally advanced rectal cancers.
abstract: BACKGROUND
  Lymphocytes and natural killer cells (NK) appear to be important in colorectal cancer. Their role in chemoradiotherapy for rectal cancers is unclear. We evaluated T-lymphocytes (CD3), sub-groups CD4 and CD8, and NK cells (CD56+CD57) in normal and rectal tumor tissues pre- and post-chemoradiotherapy, and investigated their relationship to tumor regression grade, disease-free survival and pathological stage.
  
  
  METHODS
  Tissue microarrays from colonoscopic biopsies, resection specimens and normal tissues, from 52 patients, were immunostained.
  
  
  RESULTS
  NK cell counts were significantly lower in tumor samples compared to normal tissues (p=0.007). T-lymphocyte counts were higher in post-treatment compared to pre-treatment samples (p=0.025), specifically in the CD8 subgroup after long-course treatment. The results suggested an association between post-treatment CD8 and NK cell counts with higher tumor regression. No associations were found with regard to stage or disease-free survival.
  
  
  CONCLUSIONS
  NK cell counts were significantly reduced in rectal cancers compared to normal tissues, while total T-lymphocyte counts increased post-chemoradiotherapy. Both appeared important in tumor regression.
authors.affiliation: Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia Ingham Institute for Applied Medical Research, Liverpool, Australia University of New South Wales, Kensington, Australia stephanie.lim@sswahs.nsw.gov.au.
authors.forename: Stephanie H
authors.initials: SH
authors.lastname: Lim
authors.affiliation: Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia Ingham Institute for Applied Medical Research, Liverpool, Australia.
authors.forename: Wei
authors.initials: W
authors.lastname: Chua
authors.affiliation: Molecular Medicine Research Group, University of Western Sydney, Liverpool, Australia.
authors.forename: Christina
authors.initials: C
authors.lastname: Cheng
authors.affiliation: Ingham Institute for Applied Medical Research, Liverpool, Australia University of New South Wales, Kensington, Australia.
authors.forename: Joseph
authors.initials: J
authors.lastname: Descallar
authors.affiliation: Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia Ingham Institute for Applied Medical Research, Liverpool, Australia.
authors.forename: Weng
authors.initials: W
authors.lastname: Ng
authors.affiliation: Department of Colorectal Surgery, Royal Prince Alfred Hospital, Camperdown, Australia University of Sydney, Camperdown, Australia Surgical Outcomes Research Centre, Sydney, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Solomon
authors.affiliation: Ingham Institute for Applied Medical Research, Liverpool, Australia University of Western Sydney, Campbelltown, Australia Department of Colorectal Surgery, Liverpool Hospital, Liverpool, Australia.
authors.forename: Les
authors.initials: L
authors.lastname: Bokey
authors.affiliation: Ingham Institute for Applied Medical Research, Liverpool, Australia University of New South Wales, Kensington, Australia Department of Radiation Oncology, Liverpool Hospital, Liverpool, Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Wong
authors.affiliation: University of New South Wales, Kensington, Australia Department of Radiation Oncology, Liverpool Hospital, Liverpool, Australia.
authors.forename: Mark T
authors.initials: MT
authors.lastname: Lee
authors.affiliation: Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia Ingham Institute for Applied Medical Research, Liverpool, Australia University of New South Wales, Kensington, Australia Molecular Medicine Research Group, University of Western Sydney, Liverpool, Australia University of Western Sydney, Campbelltown, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: de  Souza
authors.affiliation: Ingham Institute for Applied Medical Research, Liverpool, Australia Molecular Medicine Research Group, University of Western Sydney, Liverpool, Australia University of Western Sydney, Campbelltown, Australia Department of Anatomical Pathology, Liverpool Hospital, Liverpool, Australia.
authors.forename: Joo-Shik
authors.initials: JS
authors.lastname: Shin
authors.affiliation: Ingham Institute for Applied Medical Research, Liverpool, Australia University of New South Wales, Kensington, Australia Molecular Medicine Research Group, University of Western Sydney, Liverpool, Australia University of Sydney, Camperdown, Australia University of Western Sydney, Campbelltown, Australia Department of Anatomical Pathology, Liverpool Hospital, Liverpool, Australia.
authors.forename: Cheok Soon
authors.initials: CS
authors.lastname: Lee
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D016022:Case-Control Studies; D059248:Chemoradiotherapy; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects / Q000528:radiation effects; D016246:Lymphocytes, Tumor-Infiltrating / Q000187:drug effects* / Q000528:radiation effects*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D015996:Survival Rate; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000528:radiation effects; D046888:Tissue Array Analysis
chemical_list: D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil
keywords: CD3/CD4/CD8 lymphocytes; NK cells; colorectal cancer; radiation; tumour microenvironment