Correlation between immune microenvironment and clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites

Objectives

To explore the correlation between tumor-associated macrophages (TAMs), tumor-infiltrating lymphocytes (TILs), and tumor-associated angiogenesis (TAA) in the tumor microenvironment with the clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites (LBCL-IP).

Methods

A total of 46 cases of LBCL-IP from the Department of Pathology, the Third Affiliated Hospital of Xinjiang Medical University, from January 2010 to February 2024, were collected, along with clinical and follow-up data of LBCL-IP patients. Immunohistochemistry and triple immunofluorescence were used to detect related proteins of TAMs, TILs, and TAA, and to analyze the correlation between TAMs, TILs, TAA, and the polarization of TAMs with the clinical and prognostic factors of LBCL-IP patients.

Results

There are 30 cases (65.2 %) showed high expression of CD68 proteins, 32 cases (69.6 %) showed high expression of CD163 proteins, 19 cases (41.3 %) showed high expression of CD4 proteins, 34 cases (73.9 %) showed high expression of CD8 proteins, and 25 cases (54.3 %) showed high expression of CD34 proteins. A total of 28 cases (60.9 %) showed CD68⁺CD163⁺/CD68⁺CD86⁺≥1. The chi-square tests showed that high expression of CD163 proteins was positively correlated with elevated LDH and BMG values, and the count of CD68⁺CD163⁺/CD68⁺CD86⁺≥1 was positively correlated with ECOG scores ≥2, Ann Arbor staging III-IV, and increased BMG value. High expression of CD8 proteins was positively correlated with a Ki-67 proliferation index ≥70 %, and high MVD values were positively correlated with Ann Arbor staging III-IV. The Kaplan-Meier estimator analysis showed that LBCL-IP patients with low expression of CD68 proteins, high expression of CD163 proteins, CD68⁺CD163⁺/CD68⁺CD86⁺≥1, low expression of CD8 proteins, high MVD values, ECOG scores ≥2, Ann Arbor staging III-IV, LDH ≥250 U/L, BMG ≥2.2 mg/L, and IPI scores ≥2 had shorter survival times. Multivariate Cox regression analysis showed that low expression of CD8 proteins, CD68⁺CD163⁺/CD68⁺CD86⁺≥1, LDH ≥250 U/L, and ECOG scores ≥2 are independent risk factors affecting the survival of LBCL-IP patients.

Conclusion

M2-polarized TAMs and low infiltration of CD8⁺ TILs were more strongly correlated with poor clinical pathological indicators and worse prognosis, and MVD values may serve as an aiding means for the diagnosis and prognostic prediction of LBCL-IP disease.