• Age between 18 and 70 years old (including boundary value), both male and female.

• The first stage requires patients with malignant tumors of the digestive system (including advanced gastric cancer, advanced colorectal cancer, advanced pancreatic cancer, advanced liver cancer) who have failed previous standard treatments and have no other feasible effective treatment methods. The documents for the diagnosis of advanced digestive system malignancies include imaging reports (CT/MRI) or pathological examination results. The second stage requires patients with liver metastases of advanced digestive system malignancies (including gastric cancer liver metastasis, colorectal cancer liver metastasis, and pancreatic cancer liver metastasis) who have previously failed standard treatment and have no other feasible effective treatment methods. The investigator can judge it. Perform radiofrequency/microwave ablation therapy. Documents for diagnosing liver metastases from advanced digestive system malignancies include imaging reports (CT/MRI) or pathological examination results.

• The subject's expected survival period is ≥12 weeks.

• According to the RECIST V.1.1 standard, subjects participating in the first phase of dose escalation must have at least one target lesion that can be evaluated stably. Participants participating in the second phase of EpCAM CAR-T infusion therapy combined with local radiofrequency/microwave ablation therapy must have at least one non-target disease in the liver that is suitable for radiofrequency/microwave ablation therapy.

• The histological staining of EpCAM in the biopsy tumor tissue sample is positive.

• Subjects in the second stage require Child-Pugh classification of liver function as A or B (score ≤ 7 points).

• ECOG stamina score 0～1.

• The subject has sufficient organ and bone marrow function. Laboratory screening must meet the following standards (refer to NCI CTCAE 5.0). All laboratory test results should be within the following stable range and there is no continuous supportive treatment.

∙ Blood test: white blood cell WBC≥1.5×10\^9/L; platelet count PLT ≥60×10\^9/L; hemoglobin content Hb ≥8.0g/dL; lymphocyte LYM≥0.4×10\^9/L;

‣ Blood biochemistry: serum creatinine≤1.5×ULN, if serum creatinine\>1.5×ULN, creatinine clearance rate\>50mL/min (calculated according to Cockcroft-Gault formula); serum total bilirubin≤1.5×ULN, alanine Aminotransferase (ALT)≤2×ULN, aspartate aminotransferase (AST)≤2×ULN (ALT≤5×ULN in patients with liver metastasis or liver cancer, AST≤5×ULN).

‣ Amylase and lipase ≤ 1.5 × ULN;

‣ Routine urine examination: urine protein \<2+

• The left ventricular ejection fraction (LVEF)\>45% in cardiac color Doppler ultrasound examination within one month.

⁃ Fertility status: female patients of childbearing age or male patients whose sexual partners are females of childbearing age are willing to take effective contraceptive measures from the signing of the informed consent form to 6 months after the last cell infusion (females of childbearing age include premenopausal women and premenopausal women). Women within 2 years after menopause).

⁃ The subject must sign and date a written informed consent form.

⁃ The subject must be willing and able to comply with the predetermined treatment plan, laboratory examination, follow-up and other research requirements.