Supplemental Figure 1:Representative pictures of inflammatory cells in biliary tract cancers.

Intraepithelial, tumorinfiltrating CD8+ T-lymphocytes in an ICC (200x)(A). Tumorinfiltrating CD8+ T-lymphocytes in ECC showing perineural invasion (150x)(B). CD8+ T-lymphocytes infiltrating the desmoplastic stroma of an ECC (200x)(C).

Supplemental Figure 2:Distribution of inflammatory cell infiltrate (none vs any) in non-invasive precursors (BilIN III), tumor margin, tumor center, and metastatic lesions of biliary tract cancers.

Percentage of cases showing any intraepithelial inflammatory cell(CD4+, CD8+ T-lymphocytes, CD20+ B-lymphocytes, CD68+ macrophages, CD117+ mast cells,Foxp3+ regulatory T-lymphocytes) or any total Perforin+ NK-cell in non-invasive precursors (BilIN III), tumor margin, tumor center, and metastatic lesions of biliary tract cancers.

Supplemental Figure 3: Distribution of inflammatory cell infiltrates in biliary tract cancers stratified for tumor grade.

Total number of CD4+T-lymphocytes (A), CD8+ T-lymphocytes (B), CD20+ B-lymphocytes (C), Foxp3+ regulatory T-lymphocytes (D), CD68+ macrophages (E), and CD117+ mast cells (F)stratified for tumor grade (G1-G3).

Supplemental Figure 4:Overall survival probability in biliary tract cancer patients stratified for CD4+ T-lymphocytes and BTC subgroups.

Kaplan-Meier curves depict overall survival probability stratified for intraepithelial (A, C, E) and total (B, D, F)CD4+ T-lymphocytecontent in ICC (A, B), ECC (C, D), and GBAC (E, F). P-values were calculated with a log-rank test.

Supplemental Figure 5:Overall survival probability in biliary tract cancer patients stratified for CD8+ T lymphocytes and BTC subgroups.

Kaplan-Meier curves depict overall survival probability stratified for intraepithelial (A, C, E) and total (B, D, F)CD8+ T-lymphocytecontent in ICC (A, B), ECC (C, D), and GBAC (E, F). P-values were calculated with a log-rank test.

Supplemental Figure 6:Overall survival probability in biliary tract cancer patients stratified for FoxP3+ T lymphocytes and BTC subgroups.

Kaplan-Meier curves depict overall survival probability stratified for intraepithelial (A, C, E) and total (B, D, F) Foxp3+ T-lymphocyte content in ICC (A, B), ECC (C, D), and GBAC (E, F). P-values were calculated with a log-rank test.

Supplemental Figure 7:Overall survival probability in biliary tract cancer patients stratified for CD20+ B-lymphocytes and BTC subgroups.

Kaplan-Meier curves depict overall survival probability stratified for total CD20+ B-lymphocyte content in ICC (A), ECC (B), and GBAC (C). P-values were calculated with a log-rank test.

Table Legends:

Table 1: Overall survival in dependence of clinicopathological parameters and inflammatory cell infiltrate. Patients without adequate follow-up data were not included. P-values were calculated with a log-rank test.

Supplemental Table 1:Median numbers of total CD4+ T-lymphocytes, Foxp3+ regulatory T-lymphocytes, CD8+ cytotoxic T-lymphocytes, CD20+ B-lymphocytes, CD68+ macrophages, and CD117+ mast cells in BTC stratified for clinicopathological parameters.

Supplemental Table 2: Presence/absence of intraepithelial CD4+ T-lymphocytes,Foxp3+ regulatory T-lymphocytes, CD8+ T-lymphocytes, CD20+ B-lymphocytes, CD68+ macrophages, and CD117+ mast cells as well as presence/absence of total Perforin+ NK-cell infiltrates and CD20+ B-lymphocyte aggregates in BTC stratified for clinicopathological parameters.

Supplemental Table 3: Multivariate survival analysis under inclusion of CD4+ T-lymphocyteinfiltrate, UICC-stage and tumor grade.

Supplemental Table 4: Multivariate survival analysis under inclusion of Foxp3+ regulatory T-lymphocyte infiltrate, UICC-stage and tumor grade.

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