Ductal carcinoma in situ of the breast: immune cell composition according to subtype.

Agahozo, Marie Colombe;Van Bockstal, Mieke;Groenendijk, Floris H;van den Bosch, Thierry P P;van Deurzen, Carolien H M;et.al.
(2020) Modern Pathology — Vol. 33, n° 2, p. 196-205 (2020)

Files

2020_Agahozo_Mod_Pathol.pdf
  • Open Access
  • Adobe PDF
  • 2.29 MB

Details

Authors
  • Agahozo, Marie Colombe
    Author
  • Author
  • Groenendijk, Floris H
    Author
  • van den Bosch, Thierry P P
    Author
  • van Deurzen, Carolien H M
    Author
Show more
Abstract
Ductal carcinoma in situ of the breast includes several subtypes with a divergent biological behavior. Data regarding the composition of ductal carcinoma in situ-associated immune cells and their potential role in progression is limited. We studied ductal carcinoma in situ-associated immune response by characterizing immune cell subsets according to ductal carcinoma in situ subtypes. Ductal carcinoma in situ-associated tumor infiltrating lymphocyte (TIL) density was evaluated based on hematoxylin and eosin (H&E)-stained sections from 473 patients. Cases were subtyped based on ER, PR, and HER2. Patients were categorized as TIL-high or low. Ductal carcinoma in situ-associated immune cells of TIL-high cases were immunostained on whole slides with CD4, CD8, CD20, CD68, FOXP3, and PD-L1 (SP142 and SP263). In total, 131/473 patients (28.0%) were considered as TIL-high. The percentage of TIL-high cases was significantly higher in HER2+ and triple-negative ductal carcinoma in situ (P < 0.0001). Overall, no statistical difference in immune cell composition according to subtypes was found. However, individual subtype comparison showed that ER+ HER2+ cases had a significantly higher proportion of CD8+ T cells compared with triple-negative cases (P = 0.047). In TIL-high cases, PD-L1-SP142 expression on tumor cells was associated with subtype (P = 0.037); the lowest number of positive cases was observed in the HER2+ subtype (independent of ER). However, in TIL-high ductal carcinoma in situ, PD-L1 expression by both clones was limited. In conclusion, high numbers of TILs are predominantly observed in HER+ and triple negative ductal carcinoma in situ. The ER+ HER2+ subtype seems to attract a higher proportion of CD8+ T cells compared with the triple negative subtype. Among TIL-high cases, the HER2+ subgroup had the lowest PD-L1-SP142 expression on tumor cells. This suggests a more pronounced antitumor immunity in HER2+ ductal carcinoma in situ, which could play a role in its biological behavior.
Affiliations

Citations

Agahozo, M. C., Van Bockstal, M., Groenendijk, F. H., van den Bosch, T. P. P., Westenend, P. J., & van Deurzen, C. H. M. (2020). Ductal carcinoma in situ of the breast: immune cell composition according to subtype. Modern Pathology, 33(2), 196-205. https://doi.org/10.1038/s41379-019-0331-8 (Original work published 2020)