Pancreatic cancer and radiotherapy
Invasive pancreatic ductal carcinoma, about 90% of pancreatic tumors, contains many hypoxic cells and is often resistant to X-ray therapy. It is also surrounded by radiation-sensitive digestive organs such as the stomach and intestines, making it difficult to give a dose sufficient to control the tumor. Carbon ion beams concentrate the dose on the tumor and have strong cell-killing power, so they are considered under these conditions.
Insurance coverage in Japan
Locally advanced pancreatic cancer that is difficult to cure surgically is covered by insurance. This includes cases where surgery is impossible or not desired, primary pancreatic cancer without distant metastasis, and local recurrence after surgery. Clinical trials to develop new treatments are also under way.
Cases that are difficult to treat
Metastasis; inability to irradiate while avoiding the bowel; metal stents in the bile duct or digestive tract (tube stents in the bile duct are acceptable); ascites in the upper abdomen; general condition such as serious complications interfering with treatment; or the physician judging treatment difficult.
Procedure and schedule
The physician confirms eligibility, obtains written consent after explanation, and the case is approved by the hospital’s multidisciplinary cancer board. Making the immobilization device and taking CT for treatment planning takes about 1 week. Irradiation is 12 fractions over 3 weeks. Depending on the condition, chemotherapy is combined or carbon ion therapy is given alone, and maintenance chemotherapy following guidelines is recommended after treatment.
Side effects
Side effects may occur in normal tissue within the irradiated area and near the tumor. Major ones include digestive tract ulcers, bleeding, and vertebral compression fractures. Combining chemotherapy may increase blood-related side effects such as decreased white blood cells and platelets.