Selective Internal Radiotherapy (SIRT) is a locally applied method to treat inoperable liver metastases or primary liver tumors. The liver as a vital organ is frequently an early site of metastatic spread and a life-limiting organ in late metastatic disease. The liver is a site, where multiple localized therapeutic interventions can be applied, and multiple possibilities offered by several medical disciplines are available for local therapy.
SIRT using resinous microspheres, is a reimbursable procedure in Switzerland. The text in the Swiss catalogue (KLV) listing such procedures states: in cases of inoperable liver tumors not amenable to chemotherapy, in which other locally ablative therapies are not possible or have not shown any effect”. This holds for all liver metastases or primary liver tumors at Zurich University Hospital mainly patients in late inoperable states and after multiple lines of chemotherapy are presented to the interdisciplinary tumor board. In such cases, first an all encompassing internal medical / oncological assessment of the patient is necessary. This assessment hinges on the performance status of the patient, the identification of the primary dominant localization of the tumor in the liver, the identification of the most recently applied chemotherapy and its potential interference with a SIR-Therapy. Important prerequisites to treat the patient with a SIR-Therapy are mainly a intact liver function, i. e. the absence of ascites as a sign of an advanced liver insufficiency, elevated bilirubin (1.5x above normal values), deranged coagulation status, elevated transaminases as well as thrombocytopenia. The indication for SIRT is summarized below.
After a discussion of the procedure with the patient, the preparatory procedures for a SIR-Therapy are done. This out-patient preparation concerns mainly the angiographic planning of the therapy. Only after this angiographic preparation is the patient ready for a SIR-Therapy, and the out-patient Y-90 based therapy itself can be planned and executed. Usually, the time lag between planning and therapy is around 2 weeks. After a 5 hour observation period at the hospital, the patient can normally be sent home. The follow-up occurs in close collaboration with the referring physician and mostly under his auspices.
A SIR-Therapy done by experienced physicians generally shows very few untoward reactions. Frequently, low grade fever is observed, capsular pain is noted,and the patient complains of some nausea and fatigue for a few days. Serious complications which have to be discussed with the patient prior to the procedure, concern the migration of the injected microspheres through gastric and duodenal artieries into the corresponding organs. This is very annoying for the patient and leads to local ulcerations. These rare but possible side effects have to be discussed with the patient in the first contact with the responsible physician.
The entire process from treatment request to the end of the therapy lasts around 1 month. The treatment is done in close collaboration between Nuclear Medicine, Medical Oncology and Interventional Radiology.Additional literatureNonsurgical precedures at regional metastases of colorectal carcinoma (PDF) / only in German
Responsible physicians Nuclear Medicine
Ivette Engel-Bicik MD
University Hospital Zurich
Responsible physician, Radiology
Prof. Thomas Pfammatter MD
University Hospital Zurich
Diagnostic and Interventional Radiology
Expiry of Therapy
Indication for a SIR-Therapy
Inoperable liver tumors, which are refractory to chemo-therapy and in which other locally ablative procedures are not possible or have not shown any benefits
Patient has already received an external radiation therapy oft h liver (not applicable for stereotactic RT)
Ascites of clinical liver failure
Abnormal synthetic or excretory liver function tests (ASAT, ALAT 5x above norm, Bilirubin > 35 mumol/l)
Hepato-pulmonic shunt of more than 20% as per Tc-99m MAA scintigraphy
gastric refulux, pancreas or gut in Tc-99m-MAA scintigraphy
Dominant extrahepatic disease