Outcome Study of Cobalt Based Stereotactic Body Radiation Therapy for Patients with Inoperable Stage III Non-small Cell Lung Cancer

Abstract

Aim of this paper is to retrospectively evaluate the efficacy and toxicity of specialized Body Cobalt based system (BCBS) treatment in the senior patients group (.65 years) with Stage III non-small cell lung carcinoma (NSCLC). A total of 49 patients (41 males and 8 females) with Stage III NSCLC according to UICC TNM classification (6(th) edition) were treated using OUR-QGD™ BCBS which was designed and manufactured in China. Post treatment evaluation with follow-up information was collected from April 2001 to December 2006 in our department. Median age of enrolled patients was 71 years old (65-85). Among those patients, 36 patients were pathologically identified with squamous cell carcinoma, and the other 13 patients were confirmed as adenocarcinoma. All patients were immobilized by vacuum based immobilization mold and then performed slow CT scan without any respiration gating devices. The daily radiation prescription dose was defined at 50% isodose line covering primary lesions and metastatic lymph nodes with doses from 2.5 to 6 Gy in 5 fractions per week according to the tumor stage and internally approved treatment protocols by the Institutional Review Board (IRB). Median daily dose and total delivery dose of 50% isodose line were 4 Gy and 41 Gy, respectively. In this study group, total of 3 patients received neoadjuvant cisplatin-based chemotherapy. Tumor response evaluated 12 weeks after radiation has demonstrated 13 complete responses (26.5%), 21 partial responses (42.9%). The overall survival (OS) rate of 1-year, 2-year and 3-year was 63.3%, 40.8% and 20.4%, respectively. The median and mean survival time was 22 and 24 months. All 49 patients tolerated the treatment well and have completed the planned therapy regiment. Body Cobalt based system treatment of those over 65 years old patients with Stage III NSCLC had reasonable and superior curative effect as well as local control, and at the same time without severe radiation side effects.

A treatment planning comparison between a novel rotating gamma system and robotic linear accelerator based intracranial stereotactic radiosurgery/radiotherapy

“…The physical characteristics of RGS including radiation absorbed dose rates and profiles measured are well comparable to those measured for the commonly used Leksell Model U Gamma Knife ® unit (Goetsch et al 1999). The efficacy of gamma ray systems has been shown for both early stage and inoperable locally advanced lung cancer and in treating metastatic liver lesions (Kishan et al 2015, Wang et al 2015, Merna et al 2016. The preliminary results, done with Monte Carlo simulations, showed great potential for a novel-design RGS when compared to the well-established CyberKnife system (Eldib et al 2016a).…”

“…The main design is to focus multiple Cobalt-60 sources on target by cone shaped style rotation of the system. These sources rotate along the same axis so that the lesion at a constant focal point receives continued irradiation, whereas, surrounding normal tissue has instantaneous low dose irradiation during delivery of treatment (Wang et al 2015). Although in our results the estimated treatment time from the RGS system was comparatively less than that from CyberKnife, it could be argued that one of the drawbacks of using Cobalt-60 is the dose rate change due to the course of its useful lifespan.…”

“…Wrapping a radiation dose around normal structures using an inverse planning algorithm by non-isocentric beam delivery is the cardinal feature of RGS. Although the complete clinical scope and limitations of this system are yet to be explored fully, excellent dosimetry using Monte Carlo calculations to the head and neck, brain, thorax, abdomen, pelvis and spine treatment sites have been demonstrated (Kishan et al 2015, Wang et al 2015, Merna et al 2016. Lower beam energy and penetration associated with Cobalt-60 was not encountered as a problem.…”

Simultaneous integrated boost of intensity‐modulated radiation therapy to Stage II‐III non‐small cell lung cancer with metastatic lymph nodes

“…22 Through changing the fractionated radiotherapy dose of 2.5-6 Gy with concurrent chemoradiotherapy for locally advanced NSCLC, the CR, PR, 1, 2, 3 years OS rates, and MST were 26.5%, 42.9%, 63.3%, 40.8%, 20.4%, and 22 months, respectively. 23 A fraction dose of 3 Gy and total dose of 65-68 Gy were given after initially 50 Gy/20 fractions, the 3-years OS and progression-free survival (PFS) rates were 32.1% and 29.8%, respectively, and the 1-, 2-, and 3-years LRPFS rates were 69.6%, 60.9%, and 60.9%, respectively. 24 Based on the characteristics of IMRT, the dose of the PTV was kept at 60 Gy and the dose of GTV was 72-78 Gy synchronously, the result showed that MST was 25.3 months.…”

Simultaneous Integrated Boost of intensity modulated radiation therapy to Stage II-III Non-Small Cell Lung Cancer with metastatic lymph nodes

“…Through changing the fractionated radiotherapy dose of 2.5-6Gy with concurrent chemoradiotherapy for locally advanced NSCLC ,the CR ,PR,1, 2, 3 years OS rates and mean suivival time(MST) were 26.5%, 42.9%,63.3%, 40.8%, 20.4% and 22 months, respectively [20] . A fraction dose of 3 Gy and total dose of 65-68Gy were given after initially 50 Gy/20 fractions the 3-years OS and PFS rates were 32.1% and 29.8% respectively and the 1 -, 2-and 3-years LRPFS rates were 69.6%, 60.9% and 60.9%, respectively [21] .…”