Basic characteristics of patients with MA
Overall, we recruited 68 patients with a mean age of 60 years old. Of these, 38 (55.88%) were female whereas 30 (44.12%) were male. There were 18 cases (46.1%) of gastric cancer, 7 cases (17.9%) of colorectal cancer, 3 cases (7.7%) of biliary tract cancer, 4 cases (10.3%) of ovarian cancer, 4 cases (10.3%) of fallopian tube cancer, and 3 cases (7.7%) of pancreatic cancer. The pathological type of 39 patients was adenocarcinoma, with 22 cases (56.4%) poorly differentiated, 9 cases (23.1%) moderately differentiated, and 8 cases (20.5%) well differentiated. The median ASS of 39 patients was 6 months, including 5 months for gastrointestinal cancer, 5 months for biliary tract cancer, 20 months for gynecological cancer, and 2 months for pancreatic cancer.
In addition to 5 patients who did not receive anti-tumor therapy due to advanced age and poor general condition, the remaining 33 patients received comprehensive anti-tumor therapy, including 18 patients who received radical surgery, 33 patients who received chemotherapy, 10 patients who received immunotherapy, 8 patients who received radiotherapy, 12 patients had been treated with antiangiogenic agents such as bevacizumab and apatinib, and 15 patients had been treated with intraperitoneal infusion. Among them, 12 gastric cancer patients received intraperitoneal infusion of paclitaxel, and the ascites was relieved. 3 patients with gastric cancer received intraperitoneal infusion of bevacizumab. 1 patient with colon cancer received intraperitoneal infusion of fluorouracil, and 2 patients with pancreatic cancer received intraperitoneal infusion of cisplatin. These clinicopathological characteristics were summarized in Table 1.
Table 1
Clinicopathological characteristics of patients
Variables | No(%) |
Gender | |
Female | 16(41%) |
Male | 23(59%) |
Age | |
< 65 | 23(59%) |
≥ 65 | 16(41%) |
Primary site | |
Stomach | 18(46.1%) |
Colorectum | 7(17.9%) |
Biliary duct | 3(7.7%) |
Ovary | 4(10.3%) |
Fallopian tube | 4(10.3%) |
Pancreas | 3(7.7%) |
Degree of differentiation | |
High | 8(20.5%) |
Medium | 9(23.1%) |
Low | 22(56.4%) |
Treatment | |
Surgery | 18(46.2%) |
Chemotherapy | First-line 12(30.8%) |
Second-line 14(35.9%) |
Third-line and above 7(17.9%) |
Immunotherapy | 10(25.6%) |
Radiotherapy | 8(20.5%) |
Antiangiogenic therapy | 12(30.8%) |
Peritoneal perfusion | 15(38.5%) |
Infiltrating density of immune cells
The median percentages of CD4, CD8, CD11b, CD11c, CD16, CD19, CD163 and FOXP3 positive cells were 13.22% (interquartile range, IR 2.30%-24.80%), 8.26% (IR 3.19%-11.76%) and 51.41% (IR 37.38%), 56.87% (IR 34.37%-81.06%), 47.86% (IR 21.49%-68.22%), 13.31% (IR 2.38%-26.10%), 54.43% (IR 41.60%-66.98%), 2.52% (IR 1.10%-4.47%), respectively (Fig. 1). The proportions of positive immune cells of 39 patients were demonstrated in Fig. 2.
Factors related to prognosis
According to rank-sum test, age (P = 0.017), primary site (P = 0.039) and the infiltration level of CD4 (P = 0.047), CD163 (P = 0.02) and FOXP3 (P = 0.022) were significant for prognosis. However, gender (P = 0.071), differentiation degree (P = 0.083) and the infiltration level of CD8 (P = 0.172), CD11b (P = 0.325), CD11c (P = 0.112), CD16 (P = 0.112), CD19 (P = 0.123) were not statistically different.
Factors related to infiltrating density
The percentages of CD4 (P = 0.582), CD8 (P = 0.291), CD11b (P = 0.194), CD11c (P = 0.587), CD16 (P = 0.08), CD19 (P = 0.085), CD163 (P = 0.17) and FOXP3 (P = 0.487) positive cells have no statistical difference between subgroups with diverse differentiation degree (Fig. 3A). Meanwhile, there were no significant differences in the percentages of CD4 (P = 0.93), CD11b (P = 0.294), CD11c (P = 0.609), CD16 (P = 0.13), CD19 (P = 0.187), CD163 (P = 0.431) and FOXP3 (P = 0.394) positive cells in subgroups with different primary sites. The proportion of CD8 positive cells in patients with different tumor sites was significantly different (P = 0.014), with that in biliary tract tumors significantly higher than that in digestive tract tumors (P = 0.032) (Fig. 3B).
Univariate and multivariate analysis of prognostic factors
According to univariate analysis of clinicopathological factors, infiltrating density of positive immune cells, ICIS1 and ICIS2 revealed that gender (female vs male, HR, 0.448, 95%CI (0.221–0.908), P = 0.026), age (≥ 65vs < 65, HR, 2.436, 95%CI (1.213–4.892), P = 0.012), primary site (biliary vs digestive tract, HR, 1.812, 95% CI (0.526–6.246), gynecological system vs digestive tract, HR, 0.163, 95% CI (0.047–0.565), pancreas vs digestive tract, HR, 1.953, 95% CI (0.574–6.653), P = 0.014), CD4 (high vs low, HR, 0.409, 95% CI (0.199–0.841), P = 0.015), CD8 (high vs low, HR, 0.405, 95% CI (0.183–0.898), P = 0.026), CD163 (high vs low, HR, 2.757, 95% CI (1.111–6.845), P = 0.029), FOXP3 (high vs low, HR, 0.357, 95% CI (0.159–0.806), P = 0.013), whether to receive treatment (treated vs untreated, HR, 0.196, 95% CI (0.065–0.584), P = 0.003) and chemotherapy (treated vs untreated, HR, 0.159, 95% CI (0.055–0.462), P = 0.001), ICIS1 (high vs low, HR, 0.388, 95% CI (0.185–0.811), P = 0.012) and ICIS2 (high vs low, HR, 0.32, 95% CI (0.154–0.661), P = 0.002) were significant prognostic factors. The degree of differentiation, the proportion of CD11c, CD11b, CD16, CD19 positive cells, whether to receive surgery, radiotherapy, anti-vascular therapy, immunotherapy, intraperitoneal perfusion therapy, etc., had no statistical significance for ASS.
As such only gender, age, primary site, CD4, CD8, CD163, FOXP3, whether to receive treatment and chemotherapy, ICIS1 and ICIS2 were included in multivariate cox analysis. Except whether to receive chemotherapy (treated vs untreated, HR, 0.025, 95% CI (0.001–0.058), P = 0.016), none of the other factors indicated independent predictive value for ASS (Table 2).
Table 2
Univariate and multivariate cox analysis
| Univariate Cox | Multivariate Cox |
HR | (95%CI) | P | HR | (95%CI) | P |
Gender | | | | | | |
Female vs Male | 0.448 | 0.221–0.908 | 0.026 | 0.834 | 0.3-2.321 | 0.728 |
Age | | | | | | |
≥ 65vs < 65 | 2.436 | 1.213–4.892 | 0.012 | 1.087 | 0.393–3.008 | 0.873 |
Primary site | | | | | | |
Biliary tube vs GI tract | 1.812 | 0.526–6.246 | 0.014 | 2.704 | 0.313–23.39 | 0.165 |
Gynecology vs GI tract | 0.163 | 0.047–0.565 | 0.282 | 0.026–2.223 |
Pancreas vs GI tract | 1.953 | 0.574–6.653 | 3.458 | 0.602–19.866 |
Differentiation degree | | | | | | |
Medium vs High | 2.716 | 0.871–8.466 | 0.062 | | | |
Low vs High | 3.365 | 1.227–9.227 | | |
CD4 | | | | | | |
High vs Low | 0.409 | 0.199–0.841 | 0.015 | 0.612 | 0.083–4.501 | 0.63 |
CD8 | | | | | | |
High vs Low | 0.405 | 0.183–0.898 | 0.026 | 0.951 | 0.144–6.293 | 0.959 |
CD11b | | | | | | |
High vs Low | 1.311 | 0.651–2.64 | 0.449 | | | |
CD11c | | | | | | |
High vs Low | 0.537 | 0.263–1.096 | 0.087 | | | |
CD16 | | | | | | |
High vs Low | 1.918 | 0.955–3.856 | 0.067 | | | |
CD19 | | | | | | |
High vs Low | 2.266 | 0.91–5.642 | 0.079 | | | |
CD163 | | | | | | |
High vs Low | 2.757 | 1.111–6.845 | 0.029 | 3.268 | 0.52-20.599 | 0.207 |
FOXP3 | | | | | | |
High vs Low | 0.357 | 0.159–0.806 | 0.013 | 0.413 | 0.107–11.602 | 0.201 |
Treatment | | | | | | |
Treated vs Untreated | 0.196 | 0.065–0.584 | 0.003 | 3.95 | 0.29652.689 | 0.299 |
Surgery | | | | | | |
Treated vs Untreated | 0.539 | 0.265–1.095 | 0.087 | | | |
Chemotherapy | | | | | | |
Treated vs Untreated | 0.159 | 0.055–0.462 | 0.001 | 0.025 | 0.001–0.058 | 0.016 |
First-line vs Untreated | 0.068 | 0.018–0.256 | 0.001 | 1.245 | 0.279–5.555 | 0.781 |
Second-line vs Untreated | 0.252 | 0.084–0.757 | 1.576 | 0.434–5.727 |
Third-line and above vs Untreated | 0.123 | 0.034–0.453 | 1.487 | 0.688–3.499 |
Immunotherapy | | | | | | |
Treated vs Untreated | 1.169 | 0.556–2.455 | 0.68 | | | |
Anti-angiogenic agent | | | | | | |
Treated vs Untreated | 1.122 | 0.546–2.305 | 0.754 | | | |
Radiotherapy | | | | | | |
Treated vs Untreated | 1.589 | 0.708–3.566 | 0.261 | | | |
Peritoneal infusion | | | | | | |
Treated vs Untreated | 1.567 | 0.78–3.148 | 0.207 | | | |
ICIS1 | | | | | | |
High vs Low | 0.388 | 0.185–0.811 | 0.012 | 1.692 | 0.178-16. 088 | 0.647 |
ICIS2 | | | | | | |
High vs Low | 0.32 | 0.154–0.661 | 0.002 | 0.942 | 0.261–3.399 | 0.927 |
Kaplan-Meier analysis
Kaplan-Meier survival curves were shown according to ICIS1 and ICIS2 (Fig. 4). In ICIS1, the median ASS of the high expression group and the low expression group were 10 months and 4.5 months, respectively. In ICIS2, the median ASS of the high expression group and the low expression group is 10 months and 3 months, respectively. ICIS1 and ICIS2 both predicted the survival time of patients well (ICISl 1: high vs low, HR,0.43, 95%CI(0.22–0.84),P = 0.0065; ICIS2: high vs low, HR,0.36, 95%CI(0.16–0.79),P = 0.0007).