Proton Beam Therapy

Proton Beam Therapy is an advanced high-precision form of radiation therapy that is only available at our hospital in Kanagawa Prefecture. Since 2022, we have been proud to offer this cutting-edge treatment, which leverages the unique properties of proton beams. These beams deliver a powerful dose of radiation precisely at the tumor site, sparing surrounding healthy tissue by stopping at a specific depth. The precision minimizes side effects, while maximizing the therapeutic impact, ensuring the best possible care for our patients.

Our Strength

By using the PET/CT at our facility, we are able to create highly accurate and personalized treatment plans.
Taking advantage of our function as a general hospital, we provide safe and optimal proton beam therapy even for patients with underlying diseases.

IMPT

Our Proton Beam Therapy equipment is capable of performing intensity modulated proton beam therapy (IMPT).

The benefit of IMPT is that it can reduce the dose to normal tissues surrounding the tumor compared to conventional methods, while increasing dose concentration to the tumor. We perform IMPT on body areas with minimal respiratory motion, such as the head and neck.

The figure shows the dose distribution of IMPT (left) and conventional method (center), as well as their difference image (right). Comparing the two, it can be seen that the dose outside the tumor (in pink) is reduced in IMPT.

Our experiences

Proton beam therapy has been used to treat a variety of cancers, including childhood cancer, head and neck cancer, lung cancer, esophageal cancer, hepatocellular carcinoma, intrahepatic cholangiocarcinoma, locally advanced pancreatic cancer, prostate cancer, and local recurrence after surgery for colorectal cancer.

Proton beam therapy (2024) Number of new patients by primary tumor
Prostate cancer	59
Liver, biliary, and pancreatic cancer	29
Lung cancer	26
Head and neck tumors	9
Esophageal cancer	5
Childhood cancer	4
Brain and spinal tumors	3
Colon and rectal cancer	1
Others	4
Total	140

Q&A

What is a proton beam?

A proton beam is created by accelerating the protons, which are the nuclei of hydrogen atoms.

What is the difference between proton beam therapy and conventional radiotherapy?

Proton beam therapy is a type of radiotherapy. While conventional radiotherapy uses photon beams such as X-rays and gamma rays, proton beam therapy uses proton beams.

Process from Consultation to Proton beam Therapy?

Initial consultation at Radiation Oncology to confirm eligibility.
Multidisciplinary committee reviews and decides on proton therapy suitability.
Second visit: Detailed explanation of therapy dates, dose, and sessions.
Treatment planning with CT, MRI, and other necessary imaging.
Verification and commencement of proton beam therapy.
Treatment starts approximately 1-2 weeks after planning CT.

What is proton therapy like in practice?

A. Proton therapy is conducted five days a week (usually weekdays, with Saturday sessions if there’s a public holiday). The process is painless and comfortable, requiring you to lie on the treatment table for about 20 minutes. It’s a minimally burdensome treatment, typically done on an outpatient basis. The number of sessions varies by condition; for prostate cancer, it’s usually 20-21 sessions.

IAEA Anchor Center

Shonan Kamakura General Hospital has been designated as an IAEA Anchor Center to enhance cancer treatment quality in developing countries.