Great Lecture Hall | Development and Trends in Cancer Therapy

Professor Wang Jiying is a famous radiation oncology expert and postgraduate tutor in China, and former director of the Radiotherapy Department of China-Japan Friendship Hospital.

Professor Wang has been engaged in intraoperative radiation therapy for pancreatic cancer since the 1980s. He has studied and discussed the dose standard of intraoperative single high-dose radiation, and published "Radiation Tolerance and Damage of intraoperative single high-dose radiation", which laid a solid theoretical foundation and practical experience for guiding the clinical work of intraoperative radiation therapy for cancer, and solved the clinical problems of energy selection for electron line radiation therapy. He is one of the earliest experts to carry out tumor suitable radiotherapy in China, and has accumulated rich clinical experience in the clinical research of tumor concurrent radiotherapy and chemotherapy, radiotherapy or chemotherapy combined with hyperthermia.

Professor Wang retired and came to Yizhou Cancer Hospital to further explore the application and practice of proton in cancer treatment, accumulating a large number of clinical cases and practical experience. His exquisite medical skills, noble thoughts and sentiments, and excellent medical ethics are well received by medical staff and patients.

In his spare time, Professor Wang did not stop thinking, feeling that the current level of domestic medical technology is uneven, the standard of treatment is lacking, and the treatment of patients is very different, and he will summarize his clinical experience for many years and summarize a series of authoritative words and diagnosis and treatment conclusions, and actively share them with colleagues in the industry and patients in need.

Here, Professor Wang's main views will be shared with the readers of the public account of Yizhou Cancer Hospital.

First of all, Professor Wang Jiying pointed out that the current situation of cancer is: 1. The incidence of cancer is high; 2. Tumor occurrence is younger; 3. More advanced patients; 4. More patients relapsed after treatment.

In view of the high incidence of tumors, with the improvement of people's living standards, the demand for health care is increasing, but the medical side has failed to keep up with the treatment needs of the people, and there are many problems inside and outside the medical field, which are mainly manifested in: 1. People's awareness of cancer treatment is insufficient, the requirements are not practical, and they constantly change hospitals and doctors to seek medical treatment, delaying the treatment opportunity; 2. The majority of patients are in advanced stage. 3. Tumor treatment is not standardized; 4. Lack of professional and technical strength in tumor treatment.

Professor Wang pointed out that in view of the current situation and the characteristics of the tumor itself, one problem must be recognized, that is, for the multi-faceted nature of the tumor, a single treatment is difficult to deal with multiple problems. Therefore, the purpose of tumor treatment is: 1. Set everyone's strengths to solve the various factors existing in tumor; 2. No single solution can solve the problem alone.

Based on this, cancer patients must choose the right tumor treatment means and solve the problem in a targeted way. Factors determining tumor treatment include: 1. Location of tumor; 2. Stage of tumor development (staging); 3. Pathological types, molecular typing and genetic detection of tumors; 4. Whether the tumor has metastasized.

Professor Wang summarized and summarized the treatment methods needed for tumors in different parts. The specific combinations are shown in the following figure:

Surgery + radiotherapy + chemotherapy are the three main means of tumor treatment. With the development of technology, the three major means have been greatly developed. Among them, radiotherapy has realized the leapfrog development from traditional photon radiation to proton radiation, with less side effects and less harm, bringing good news to tumor patients.

In terms of surgery, the surgical methods have been developed from major surgery to minor surgery or minimally invasive surgery, or the tumor can be removed with the cooperation of electronic scopes such as thoracoscope and laparoscope, and the surgical manipulator (Da Vinci surgical robot) can also be operated at a distance. These technological developments have taken cancer surgery to a new level.

However, the biggest problem of surgery is that it can not treat all tumors, it is only one of the means of tumor treatment, and only for limited parts and organs of early tumors, it is difficult to carry out surgery treatment:

1. The tumor of vital organs is too large, and it is difficult to completely remove the tumor in local operation, and the whole organ resection will affect the life of the patient;

2. The tumor is adhered to or infiltrated with vital organs, which is difficult to be removed by surgery. If the tumor is completely removed, the future quality of life of the patient will be affected;

3. Tumors with multiple metastases cannot be completely removed by surgery. Even if all tumors are removed at that time, tumors will reappear in other parts;

4. The patient has poor physique, poor cardiopulmonary function, and is difficult to withstand surgery.

As for chemotherapy, new drugs are emerging in endlessly on the market at present, but the efficacy is unsatisfactory, and the toxic reaction is still very large. Targeted drugs are advancing rapidly, but the cost is getting higher and higher, and the general population is unable to afford it.

In contrast, radiotherapy can be targeted in several stages of tumor I to IV, and the prognosis is relatively good.

Contribution and status of radiation therapy in cancer treatment: 70% of cancer patients require radiation therapy at various stages of treatment.

The development of tumor radiotherapy technology relies on the rapid development of diagnostic equipment and treatment equipment. From two-dimensional radiotherapy in the 1980s to three-dimensional radiotherapy in the 1990s, it has entered the stage of four-dimensional modulated intensity radiotherapy in the 20th century, and then in the 2020s, controlled rays such as protons have developed radiotherapy into a new era.

Technical issues related to radiation therapy have also made great progress, including: 1. Positioning systems (CT, MRI, PET-CT) can accurately locate tumors and clearly show the extent of tumor invasion. 2. The positioning and treatment of tumor patients are fixed, which can accurately locate the tumor target area; 3. Breath-gated radiation therapy and image-guided (IGRT) can effectively overcome the problem of tumor movement off-target (involuntary movement of the human body and organ movement with breathing) in precision radiation therapy; 4. Stereotactic modulated intensity modulated radiation therapy (multi-directional ray projection technology) can greatly solve the problem that tumor radiation dose is limited to the normal tissue around the tumor. With the advancement of technology, radiation therapy can effectively solve many problems existing in traditional tumor therapy.

The emergence and application of proton therapy has further brought radiotherapy into a new field. Due to the natural Bragg Peak property of protons, proton therapy has low damage to organs and tissues in the front of the tumor, and no damage in the rear, and can deliver high dose of radiation therapy to the tumor. It has been reported that it can increase the cure rate of tumor radiotherapy by 20-30%.

Professor Wang Jiying also used an image to easily reveal the effects of conventional X-rays and proton lines on cancer tissue and surrounding tissues. As follows:

When the X-ray irradiates the tumor tissue, the path through which the X-ray passes forms a "meter" shaped structure, which not only kills the tumor tissue, but also has a joint effect on the surrounding tissue, killing 1,000 enemies and self-damaging 800, and the toxic side effects are obvious. When proton line irradiates tumor tissue, there are only a few paths, and only a small amount of ray energy is released before reaching the tissue, and the energy release is 50% lower than that of X-ray. After arriving at the tumor tissue, it will be released in a concentrated manner, and then rapidly decline, and it is unable to release behind the tumor tissue, thus forming a minimal damage to the surrounding tumor tissue. This also makes it possible to release high doses against tumor tissue, enhancing the destruction of tumor tissue.

Professor Wang Jiying also took chordoma as an example, pointing out that the 5-year survival rate of intracranial chordoma treated with proton heavy ion has been reported in recent literature to be more than 90.9%.

Chordoma, a primary malignant bone tumor, mostly occurs in the intracranial and sacrum, and is difficult to be completely resected by surgery. Besides, the traditional chemoradiotherapy is not effective, and the treatment is very difficult. The 5-year survival rate is low, even for the surgically resected sacral chordoma, the 5-year survival rate is only 59.5%.

The American journal Cureus published a study evaluating proton therapy for skull base chordoma in 2021. The researchers believe that proton therapy for postoperative radiotherapy for chordoma can maximize the protection of organs at risk, such as the brain stem and visual organs.

The study included 10 patients with skull base chordoma who received proton therapy from 2017 to 2020. The results showed that both local control rate and overall survival rate were as high as 100%[1]. There were no grade 3 or higher complications in this study.

The Department of Radiation Oncology at the University of Florida College of Medicine published a 2021 study on proton therapy for chordoma in children. The study included 29 children with nonmetastatic chordoma receiving proton therapy with a median age of 14.8 years between 2008 and 2018. With a median follow-up of 4.3 years, the predicted 5-year local control rate was 85%, 5-year progression-free survival was 82%, and 5-year overall survival was 86%.

The actual results were better than predicted. Real results showed that the 5-year local control rate was 92%, the 5-year progression-free survival rate was 92%, and the 5-year overall survival rate was as high as 91%[2].

The advantage of proton therapy is the result of the progress of medical technology and the result of the unremitting efforts of the majority of medical staff. However, for specific patients how to choose treatment results, Professor Wang Jiying finally put forward two principles of tumor treatment:

1. Rational use of major tumor treatment methods. According to the organ where the tumor is located, and the relationship between the tumor and the surrounding organ tissue; According to the pathological classification of tumors, molecular typing, clinical stages and other factors, according to the recommendations of treatment guidelines and expert consensus, as well as the patient's specific physical conditions, personal will to determine the treatment process and treatment options, which is a scientific and reasonable decision.

2. Multidisciplinary collaborative comprehensive treatment. According to the clinical characteristics of the lesion, reasonable arrangement of treatment order, with different advantages of treatment technology, to solve the different problems encountered in the treatment, inhibit the development of the lesion, eliminate the tumor.

Finally, I hope that the world is cancer-free, and I hope that all cancer patients can get high-quality diagnosis and treatment.

reference

[1]Parzen J S, Li X, Zheng W, et al. Proton therapy for skull-base chordomas and chondrosarcomas: initial results from the beaumont proton therapy center[J]. Cureus, 2021, 13(5).

Wang Jiying, chief physician, radiation oncology expert, postgraduate tutor

Academic appointment

·2023 "Special Contribution Award" winner of Yizhou Cancer Hospital

· Former Director of Radiotherapy Department of China-Japan Friendship Hospital in Beijing

· Member of Beijing Branch of Tumor Radiotherapy Committee of Chinese Medical Association

· Standing Director of Radiation Therapy Specialist Technician Branch of Beijing Medical Doctor Association

· Member of tumor hyperthermia Committee, Chinese Medical Association

· Vice Chairman of the China-Japan Friendship Association Hyperthermia Committee

· Member of the Expert Committee of Beijing Cancer Radiotherapy Quality Control Center

Experience and honor

He has been engaged in tumor radiotherapy for 41 years, and began to engage in intraoperative radiotherapy for pancreatic cancer in the 1980s. He studied and discussed the dose standard of intraoperative single high-dose radiotherapy, and published Radiation Tolerance and damage of intraoperative single high-dose Radiotherapy, which laid a solid theoretical and practical experience for guiding the clinical work of intraoperative radiotherapy for cancer. In 1987, he was one of the first experts to carry out tumor suitable radiation therapy in China. He has accumulated rich clinical experience in the clinical research of tumor simultaneous chemoradiotherapy, radiotherapy or chemotherapy combined with hyperthermia. In 2002, he carried out the project of radio-iodine-125 particle tumor intertissue implantation and distance radiation therapy.