Safety of 32P BioSilicon in Patients With Hepatocellular Carcinoma

Inclusion Criteria: 1. Written informed consent. 2. Male or female patients equal to or greater than 18 years old. 3. Patients with diagnosis of hepatocellular carcinoma (HCC) meeting one of the criteria below: 1. Histology OR 2. Radiological evidence'\*' of HCC demonstrated by dynamic contrast enhanced computed tomography (CT) or dynamic contrast enhanced magnetic resonance imaging (MRI) \>/ 1cm AND serum AFP of at least 400 mcg/L OR 3. Radiological evidence'\*' of HCC demonstrated by dynamic contrast CT or dynamic contrast enhanced MRI \>/ 1cm AND serology positive for hepatitis B or C infection. '\*' Criteria for radiological evidence of HCC are: central enhancement on hepatic arterial phase AND wash out on portal venous or delayed phase. 4. Hepatic tumour mass not amenable to surgical resection or patient refuses surgery. 5. ECOG performance status 0 - 2. 6. Okuda stage I - II 7. Total volume of any single treatable tumour not more than 65 cc (not more than approximately 5 cm in longest dimension). 8. Total treatable volume of not more than 125 cc (Group 1), 111 cc (Group 2), 139 cc (Group 3) - as defined by maximum radioactivity level (MBq) for the respective groups. 9. Adequate haematological, renal and hepatic functions as defined by the following laboratory values obtained within 14 days prior to Visit 2 * Absolute granulocyte count (AGC) \>/1500 cells/mm3 * Serum creatinine \< 2 times upper limit of normal (ULN) * Serum bilirubin \< 3 times ULN * ALT (SGPT) \< 5 times ULN and/or AST (SGOT) \< 5 times ULN within 24 hours prior to implantation (Supportive care and correction permitted) Platelet count \>/ 60,000/mm3 (60 x 10\^9/L) * Prothrombin time \< 3 seconds prolonged 10. Women of childbearing potential must have a negative urine pregnancy test within three days of Visit 2. 11. Contraception must be used (both male and female) for six months after implantation and during the duration of the whole study. 12. Patients must be accessible for treatment and follow up. Exclusion Criteria: 1. Clinical encephalopathy 2. Patients younger than 18 years old. 3. No life threatening tumours in other sites (e.g. brain) 4. Less than four weeks after local therapy with radiofrequency ablation (RFA), or ethanol, and less than six weeks after local therapy with transarterial chemoembolization therapy (TACE), or since prior chemotherapy or biologic therapy (e.g. immunotherapy, systemic vaccine therapy). 5. Prior radiotherapy to liver, pancreas or gastrointestinal tract. 6. Total volume for each tumour is greater than 65 cc (greater than approximately 5 cm in longest dimension). 7. Amenable to surgery. 8. Pregnant or lactating females. 9. Other diagnosed malignancy within the last five years, which may impact on study outcome. 10. Life expectancy of less than 12 weeks. 11. Patients with a significant history of cardiac disease, that is, uncontrolled high blood pressure, unstable angina, congestive heart failure, myocardial infarction within the past three months and cardiac ventricular arrhythmias requiring medication. 12. Patients with serious active infection or other serious underlying medical conditions that would impair the ability of the patient to receive protocol treatment at implantation visits. 13. Patients with any condition (e.g. psychological) that does not permit compliance with the protocol. 14. Patients who are known to be HIV positive. Testing is not required in the absence of clinical signs and symptoms suggestive of HIV infection.