Irreversible Electroporation for Inoperable Hepatic and Pancreatic Malignancy

Inclusion Criteria: * Inclusion criteria for hepatic malignancy: 1. Signed informed consent by patient 2. Age above 18 years 3. Child-Pugh A or B cirrhosis 4. Eastern Cooperative Oncology Group performance (ECOG) score 2 or below 5. No serious concurrent medical illness 6. Histologically or cytologically proven malignant liver tumor, or lesions of size 1 to 2 cm, with typical features of hepatocellular carcinoma (HCC) on two dynamic imaging techniques, or lesions larger than 2cm, with typical features on one dynamic imaging techniques, or lesions larger than 2cm with Apha Fetal Protein (AFP) level \> 200 ug/L 7. Inoperable HCC due to patient or tumor factors, without extra-hepatic involvement on Chest X-ray (CXR) and CT 8. Massive expansive tumor type of HCC with measurable lesion on CT 9. Recurrent intrahepatic HCC after surgical resection or local ablation 10. Metastatic liver tumor with well-defined margin 11. Tumor size \<= 3cm in largest dimension 12. Tumor number \<= 3 * Inclusion criteria for pancreatic malignancy: 1. Signed informed consent by patient 2. Age older than 18 years. 3. Any kind of histologically or radiologically diagnosed malignant pancreatic tumor. 4. Tumor size \<= 3cm in largest dimension 5. Surgical treatment is considered not an option because of patient factors or tumor factors, such as those with vascular encasement or regional lymph node metastasis 6. Locally recurrent pancreatic tumor after surgical resection 7. Karnofsky's performance status of 50% or greater. 8. Life expectancy greater than 3 months. 9. Normal coagulation profile (INR \<1.5; platelet count \>50 10\^9/L). 10. Willingness and ability to complete follow-up interviews and imaging investigations following the treatment. Exclusion Criteria: * Exclusion criteria for hepatic malignancy: 1. History of prior malignancy except on the condition that the patient has been disease free for ≥3 years 2. Concurrent ischemic heart disease or heart failure 3. Biliary obstruction not amenable to percutaneous drainage 4. Child-Pugh C cirrhosis 5. Intractable ascites not controllable by medical therapy 6. History of variceal bleeding within last 3 months; serum total bilirubin level \> 50 umol/L 7. Serum albumin level \< 25g/L 8. INR \> 1.5, platelet count \<50 10\^9/L 9. Infiltrative or diffuse tumor 10. Hepatic vein tumor thrombus 11. Pregnancy 12. Cardiac arrhythmia 13. Uncontrolled hypertension * Exclusion Criteria for pancreatic malignancy: 1. Patient has active infection. 2. Patient has bleeding tendency. 3. Presence of portal vein thrombus. 4. Tumour size of greatest dimension \>3cm. 5. Tumor with ill defined infiltrative margin. 6. The tumor has invaded the duodenal wall. 7. Presence of distant metastasis 8. Currently experiencing an episode of major mental illness (psychosis, major affective disorder, or schizophrenia). 9. Pregnancy 10. Cardiac arrhythmia 11. Uncontrolled hypertension