Source: proton China

American time on March 18, 2017, 2017, multidisciplinary symposium on thoracic oncology in San Francisco, United States, concluded. At the meeting, proton treatment again gained widespread attention with its excellent treatment in patients with recurrent lung cancer.
All the treatment of recurrent lung cancer is a challenge for doctors and patients, because of recurrence of lung cancer patients are usually not suitable for surgery, and radiation accumulation of important tissues surrounding the tumor (such as heart, lung and esophageal health effects) also limits the application of received radical radiotherapy in patients with lung cancer recurrence in radiotherapy in the past, it has become a common palliative treatment for patients with lung cancer recurrence, the main purpose is to relieve pain, relieve symptoms.
Previous studies have confirmed that proton therapy, with its Bragg peak advantage, can be used in recurrent radiotherapy for recurrent tumors. This multidisciplinary symposium in thoracic oncology professor Zhang Yujiao as Senior Author, Jennifer Ho as the first author of the "doctor of chest tumor conformal proton radiotherapy and radiotherapy" for the first time that intensity-modulated proton therapy (IMPT) can be a safe and effective treatment for patients with lung cancer recurrence and prolong survival time of patients, significant reduce treatment-related toxicity, this is the first and so far into the study of chest tumor IMPT samples the maximum number of reradiotheraphy.
"Patients who have previously received thoracic radiation therapy is a condition in which clinicians often encountered, how to make the patients received doses large enough to eliminate new tumors, but not in healthy tissue of patients with serious injury is a difficult problem faced by clinicians." The study's first author, MD Anderson cancer center, radiation oncology resident Jennifer Ho said, "our study first confirmed that IMPT can be a safe and effective treatment for these patients, and can improve the local control rate of patients without severe toxicity under the."
"In the past, 20%-30% patients experienced moderate to severe or even fatal toxic reactions after undergoing radiotherapy. We know that the use of IMPT technology allows for more accurate treatment plans and better protection of health organizations, but we are not sure whether this advantage of IMPT technology can translate into better clinical outcomes." Professor Senior Author Zhang Yujiao of the MD Anderson cancer center and professor of radiation oncology research, said, "our results confirm that compared with other types of radiation therapy, the use of IMPT Technology (the implementation of reirradiation for recurrent lung cancer patients) can obtain better local control rate and survival rate, and little toxicity, showed that IMPT is an ideal treatment method for patients with chest tumor recurrence."
Key Points
In this study, the median survival time was 18 months after IMPT radiotherapy
At 1 years of follow-up, the irradiation dose is higher than or equal to the median dose of IMPT re radiotherapy patients with local recurrence free survival for patients with low dose IMPT and radiotherapy 2 times (100% vs 49%); local treatment failure rate is almost IMPT and then received low doses of radiotherapy in patients with 4 times (84% vs 23%); 1 year progression free survival rate than the low dose IMPT Reradiotheraphy were nearly 5 times higher (76% vs 14%)
IMPT Reradiotheraphy is well tolerated, only 2 patients (7%) had moderate to severe long-term pulmonary toxicity small part of the edited translation please preview:
Materials and methods
The study included 27 patients with recurrent lung cancer who underwent IMPT re radiotherapy at the MD Anderson Cancer Center for 2011-2016 years. Each patient underwent 4D-CT modeling and tumor motion analysis, and individualized tumor motion dose uncertainty analysis was performed for each patient. All patients included in the previous trial had received radiotherapy for lung cancer recurrence, 93% received IMPT Reradiotheraphy, another 7% had received radiotherapy for stereotactic radiotherapy, dose 66Gy patients (43.2-84Gy).
experimental result
22 of the patients (81%) for non-small cell lung cancer patients, the median follow-up time was 11.2 months (still alive after treatment were followed up for 25.9 months), the median overall survival (overall, survival, OS) for 18 months, more than half (54%) of total survival of patients after treatment for 1 years. 1 years and 2 years, no local treatment failure rate (local failure, LF) were 78%; 1 years without local recurrence rate (local-regional relapse, LRR) and 1 year progression free survival (progression-free survival, PFS) were 61% and 51%. Patients without 66Gy or above radiation exposure for 1 years had no local recurrence rate significantly higher than those with radiation doses below 66Gy. The patients with high grade of T, large squamous cell carcinoma and recurrent tumor were related to the poor overall survival rate. All patients were well tolerated by radiotherapy, and only 2 patients (7%) developed grade 3 pulmonary toxicity. No grade 3 or more esophagitis occurred, and no grade 4-5 toxicity occurred in 3 patients.
Test conclusion
The results show that IMPT can improve the local control rate in patients with recurrent lung cancer and prolong the survival time. The treatment toxicity is very low and the patients are well tolerated. The results also show that high dose radiation can improve the clinical efficacy, and IMPT can be a safe and effective option for patients with chest tumor undergoing radiotherapy. (proton China compilation report)
Reference
J.C.Ho, Q.N. Nguyen, H. Li, P.K. Allen, X. Zhang, X.R. Zhu, D.R. Gomez, S.H. Lin, 1M.T. Gillin, R.U. Komaki, Z. Liao, S.M. Hahn, and J.Y. Chang Reirradiation of Thoracic Cancers with; Intensity Modulated ProtonTherapy