Prognostic value of CD45RO(+) tumor-infiltrating lymphocytes for locally advanced rectal cancer following 30 Gy/10f neoadjuvant radiotherapy.
OBJECTIVE
This study aims to evaluate the prognostic value of CD45RO(+) tumor-infiltrating lymphocytes (TILs) in locally advanced rectal cancer treated with 30 Gy/10 fraction (10 f) neoadjuvant radiotherapy.


METHODS
This retrospective study involved 185 patients with locally advanced rectal cancer who underwent 30 Gy/10 f nRT (biologic equivalent dose, 30 Gy) followed by total mesorectal excision (TME) between August 2003 and October 2009. The density of CD45RO(+) TILs was assessed by immunohistochemistry using an image-analysis system and tissue microarray and was evaluated for its association with histopathologic features along with disease-free survival (DFS).


RESULTS
Following neoadjuvant radiotherapy, the median density of CD45RO(+) TILs is 654/mm(2). High density of CD45RO(+) TILs was significantly associated with increased T and N downstaging effect (p = 0.006; p = 0.014), lesser-advanced T stage (p = 0.003) and TNM stage (p = 0.022). Prolonged DFS (89.0 vs. 68.1%) was also observed in CD45RO(+Hi) cases. On multivariate regression model, CD45RO(+) TILs (p = 0.026; odds ratio (OR), 0.436 (95% confidence interval (CI), 0.209-0.907)), tumor differentiation (p = 0.057; OR, 1.878 (95% CI, 0.982-3.593)), ypT stage (p = 0.066; OR, 2.383 (95% CI, 0.943-6.025)), and ypN stage (p = 0.009; OR, 2.612 (95% CI, 1.266-5.388)) were independent factors for DFS.


CONCLUSIONS
The density of CD45RO(+) TILs cannot only predict tumor downstaging and ypTNM stage for rectal cancer following 30 Gy/10 f nRT but also promisingly predict long-term outcomes. These findings may be used to stratify patients and make alternative strategy of adjuvant treatment.
Department of Colorectal Surgery, Peking University Cancer Hospital and Institute, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), 52 Fu Cheng Lu, Haidian district, Beijing, 100142, People's Republic of China.
Lin
L
Wang
Zhi-Wei
ZW
Zhai
Deng-Bo
DB
Ji
Zhong-Wu
ZW
Li
Jin
J
Gu
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017493:Leukocyte Common Antigens / Q000276:immunology; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000276:immunology / Q000473:pathology* / Q000532:radiotherapy* / Q000601:surgery; D012189:Retrospective Studies; D046888:Tissue Array Analysis; D055815:Young Adult
D017493:Leukocyte Common Antigens