CD3+, CD4+ & CD8+ tumour infiltrating lymphocytes (TILs) are predictors of favourable survival outcome in infiltrating ductal carcinoma of breast.

BACKGROUND & OBJECTIVES: Tumour infiltrating lymphocytes (TILs) represent the host immune response against cancer cells associated with good or bad prognosis in different tumour types. This study was undertaken to evaluate the significance of CD3+, CD4+ and CD8+ TILs in breast cancer tissues in relation to clinico-pathological variables and survival outcome. METHODS: Immunohistochemistry (IHC) was performed with antibodies against CD3, CD4 and CD8 antigens on formalin-fixed paraffin-embedded tissue sections of 150 breast cancer patients. Intratumoural and stromal TIL counting was performed semiquantitatively. RESULTS: The higher CD3+, CD4+ and CD8+ intratumoural and stromal counts showed independent and direct association with good prognosis. The prognostic predictor value of intratumoural counts was higher than stromal counts. The independent associations of intratumoural and stromal counts became more prominent when adjusted with stage and grade, respectively. Among intratumoural counts, the high (++/+++) CD4+ count (OR=3.85, 95% CI=3.28-16.71, P<0.001) showed the highest survival followed by CD3+ (OR=2.70, 95% CI=1.76-8.30, P=0.001) and CD8+ (OR=2.58, 95% CI=1.55-5.86, p0 =0.001) the least when compared to respective low (+) counts. In contrast, among stromal counts, the high CD8+ count (OR=3.13, 95% CI=2.20-9.57, p0 <0.001) showed the highest survival followed by CD4+ (OR=3.02, 95% CI=2.07-8.89, p0 <0.001) and CD3+ (OR=2.45, 95% CI=1.53-6.73, p0 =0.002) the least. INTERPRETATION & CONCLUSIONS: Our results suggest that intratumoural CD4+ and stromal CD8+ counts by immunohistochemistry may serve as an independent prognosticator for favourable outcome in breast cancer.

Is the tumor infiltrating natural killer cell (NK-TILs) count in infiltrating ductal carcinoma of breast prognostically significant?

PURPOSE: The aim of this study was to investigate the prognostic significance of the CD56+NK-TIL count in infiltrating ductal carcinoma (IDC) of breast. MATERIAL AND METHODS: Immunohistochemistry (IHC) was performed using antibodies specific for CD56 on formalin-fixed and paraffin-embedded tissue sections of 175 infiltrating ductal carcinomas (IDC) of breast. Distribution of intratumoral and stromal CD56+NK-TILs was assessed semi-quantitatively. RESULTS: A low intratumoral CD56+count showed significant and inverse associations with tumor grade, stage, and lymph node status, whereas it had significant and direct association with response to treatment indicating good prognosis. These patients had better survival (χ2=4.80, p<0.05) and 0.52 fold lower death rate (HR=0.52, 95% CI=0.28-0.93) as compared to patients with high CD56+ intratumoral count. The association of survival was insignificant with low CD56 stromal count as compared to high CD56 stromal count (χ2=1.60, p>0.05). CONCLUSION: To conclude, although NK-TIL count appeared as a significant predictor of prognosis, it alone may not be sufficient for predicting the outcome considering the fact that there exists a crosstalk between NK-TILs and the other immune infiltrating TILs.