Correlation of Tertiary Lymphoid Structures in Breast Ductal Carcinoma in Situ and Adverse Pathological Parameters

Abstract

Objective: To evaluate the tertiary lymphoid structures in ductal carcinoma in situ of breast their association with clinical outcomes, immune cell markers and pathological features.

Study Design: Prospective study

Place and Duration of Study: This study was conducted at the Pathology Department, Faisalabad Medical University, Faisalabad in one year duration from June 2022 to May 2023.

Materials and Methods: A total of 210 patients who were diagnosed with DCIS were enrolled in study.  Positive tumors were labeled when there was one or more TLS in the lesion area and it was negative when no TLS found. Classification of TLS-positive tumors was made as tumors with TLSs covering less than 5% of the lesional area was categorized as having a low TLSs area percentage, while tumors with TLSs covering 5% or more of the lesion area were categorized as having a high TLSs area percentage.

Results: There were 69.0% patients with TLSs negativity and 31.0% patients with TLSs positivity. It was noted that the presence of TLSs were associated with HER2 positivity (p=0.001), triple negativity (p=0.047), TILs (25% cut-off) (p<0.001) and FoxP3 (1% cut-off) (p<0.001). Further, high TLSs (≥5%) was associated with calcifications (p<0.001), HER2 positivity (p=0.012), triple negativity (p<0.001), TILs (25% cut-off) (p<0.001), FoxP3 (1% cut-off) (p<0.001), CD4/CD8 ratio (1% cut-off) (p=0.016) and PD-L1 in TILs (1% cut-off) (p=0.043).

Conclusion: Tertiary lymphoid structures are significantly associated with negative hormone receptors, triple negativity, HER2 positivity, necrosis in situ but significance was not appropriate with recurrence and invasive behavior.