28 Primary and secondary liver malignancies

Primary and secondary liver malignancies

4

THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 15/07/2022

Figure 1: Couinaud classification of liver anatomy divides the liver into eight functionally independent segments

TABLE 1 ANATOMIC STRUCTURES AND POTENTIAL RISK ASSESSMENT FROM CATHETER PLACEMENT AND BRACHYTHERAPY TREATMENT Anatomic structure Potential risk of A) catheter placement Costodiaphragmatic recess Pneumothorax, Hemothorax, Compartment barrier disruption Arteries (intercostal, epigas-tric, mammarian, liver) Hemorrhage, arterio-portal Fistulas, arterio-biliary Fistulas, Sepsis Portal vein Hemorrhage, Fistulas Liver veins Air embolism, minor Hemorrhage, Fistulas Biliary tracts Biliary leakage, Abscess, Fistulas (to vessels, to abdominal cavity, to skin) Stomach, bowel, colon Perforation (Chilaiditi syndrome) Intercostal nerves Nerve damage

B) radiation Duodenum

Ulcer, Perforation, Abscess Ulcer, Perforation, Abscess

Stomach

Leakage, Biliary leakage, Duct scaring and pre-stenotic Dilatations, Abscess (increased when papillary Insufficiency)

Biliary tract

Adrenal glands

Radiation induced hypofunctionality Radiation induced hypofunctionality

Kidney

Lung

Radiation pneumonitis

such as accessory lobes, accessory fissures or vessels, as well as acquired changes such as cirrhosis, post-operative and radiogenic alterations. During the catheter planning process, information on target location, distance to radiation sensitive surrounding OARs, anatomic structures in the path of ideal catheter position (e.g. costodiaphragmatic recess, epigastric, intercostal and mammary arteries as well as hepatic arteries, portal-veins and biliary tracts) are evaluated to plan a safe but comprehensive procedure. During the catheter placement, fluoroscopic CT (step ii) is used to account for dynamic changes that might affect liver position or morphometry such as inspiration depth. Furthermore, anticipation of pain,

even under conscious sedation, can lead to subconscious evasion movements or unilateral muscle contractions, which in turn can result inmovement of the liver. Recognition of vascular structures on CT (see figure 2) during catheter placement facilitates the avoidance of arteries and biliary structures as well as the associated risk of bleeding, biliary leakage or fistulas. The radiotherapy simulation CT (step iii) is used to assess distances between the placed catheters, the target lesion andOARs, including duodenum, bowel, stomach, kidneys, adrenal glands, coronary arteries, ribs, spleen and lung (see table 1).