Published online Oct 10, 2016. doi: 10.5306/wjco.v7.i5.387
Peer-review started: April 18, 2016
First decision: June 12, 2016
Revised: August 13, 2016
Accepted: September 21, 2016
Article in press: September 23, 2016
Published online: October 10, 2016
Processing time: 173 Days and 9.7 Hours
To determine influence of neoadjuvant-chemotherapy (NAC) over tumor-infiltrating-lymphocytes (TIL) in triple-negative-breast-cancer (TNBC).
TILs were evaluated in 98 TNBC cases who came to Instituto Nacional de Enfermedades Neoplasicas from 2005 to 2010. Immunohistochemistry staining for CD3, CD4, CD8 and FOXP3 was performed in tissue microarrays (TMA) sections. Evaluation of H/E in full-face and immunohistochemistry in TMA sections was performed in pre and post-NAC samples. STATA software was used and P value < 0.05 was considered statistically significant.
Higher TIL evaluated in full-face sections from pre-NAC tumors was associated to pathologic-complete-response (pCR) (P = 0.0251) and outcome (P = 0.0334). TIL evaluated in TMA sections showed low level of agreement with full-face sections (ICC = 0.017-0.20) and was not associated to pCR or outcome. TIL in post-NAC samples were not associated to response or outcome. Post-NAC lesions with pCR had similar TIL levels than those without pCR (P = 0.6331). NAC produced a TIL decrease in full-face sections (P < 0.0001). Percentage of TIL subpopulations was correlated with their absolute counts. Higher counts of CD3, CD4, CD8 and FOXP3 in pre-NAC samples had longer disease-free-survival (DFS). Higher counts of CD3 in pre-NAC samples had longer overall-survival. Higher ratio of CD8/CD4 counts in pre-NAC was associated with pCR. Higher ratio of CD4/FOXP3 counts in pre-NAC was associated with longer DFS. Higher counts of CD4 in post-NAC samples were associated with pCR.
TIL in pre-NAC full-face sections in TNBC are correlated to longer survival. TIL in full-face differ from TMA sections, absolute count and percentage analysis of TIL subpopulation closely related.
Core tip: We evaluated a series of 98 triple negative breast cancer cases who received neoadjuvant chemotherapy. Pre-neoadjuvant chemotherapy and post neoadjuvant chemotherapy samples were analyzed. We compared tumor-infiltrating lymphocytes evaluated in whole slides vs in tissue microarray slides. We also compared subsets of tumor-infiltrating-lymphocytes (TILs) evaluated through an absolute counting vs a percentage calculation. Our results confirm the predictive and prognostic role of tumor infiltrating lymphocytes, and evaluated the behavior of tumor infiltrating lymphocytes and lymphocyte subsets during chemotherapy in triple negative breast cancer. Our results increase the understanding of methodological issues for TIL evaluation as well as provide information about variation of the whole TIL population and TIL subpopulation during chemotherapy.