Intensity-modulated Radiotherapy (IMRT) With Simultaneous Integrated Boost (SIB) for Inoperable Non-small-cell Lung Cancer

Intensity-modulated Radiotherapy (IMRT) With Simultaneous Integrated Boost (SIB) for Inoperable Non-small-cell Lung Cancer

Intensity-modulated Radiotherapy (IMRT) With Simultaneous Integrated Boost (SIB) Dose Escalation to the Gross Tumor Volume (GTV) With Concurrent Chemotherapy for Stage II/III Non-small Cell Lung Cancer (NSCLC)

Lung cancer is one of the most common cancer and the leading causes of cancer death in worldwide. Approximately 80% of NSCLC were inoperable. The prognosis of patients with LA-NSCLC remains disappointing. Investigators hypothesized that use of simultaneous integrated boost intensity modulated radiotherapy (SIB-IMRT) technology can safety increasing the radiation dose and benefit for inoperable NSCLC patients.

Lung cancer is one of the most common cancer and the leading causes of cancer death in patients worldwide. Approximately 80% of NSCLC were inoperable. Concurrent chemo-radiation therapy (CCRT) is a standard treatment for locally advanced NSCLC who are not candidates for surgery. Nevertheless, the prognosis of patients with locally advanced NSCLC (LA-NSCLC) is still poor. Local control (LC) after CCRT is one of the most important prognostic factors. Local failure is common after standard-dose chemoradiation for NSCLC. Studies of stereotactic body radiation therapy (SBRT) have shown a steep dose response in treating early-stage lung cancer. Improving the total dose and shortening the overall treatment time may be effective for improving the LC rates. However, problems remain due to the toxicity to adjacent critical structures (e.g,lung,heart, esophagus), the target volumes usually limits the doses escalated that cannot be safely delivered by conventional radiotherapy techniques. In order to avoid the acute and late radiation toxicity of normal tissues, different dose prescriptions can be delivered to different target volumes in the same fraction, which deliver a higher dose to the Gross Tumor Volume (GTV) and a relatively lower dose to the subclinical disease. The technique is called simultaneous integrated boost intensity modulated radiotherapy (SIB-IMRT). Investigators hypothesized that use of SIB-IMRT technology can safety increasing the radiation dose and benefit for inoperable NSCLC patients.

For all patients, the dose to the PTV will be kept constant at 60 Gy in 30 fractions at 2.0 Gy per fraction, SIBV will be kept constant at 72 Gy in 30 fractions at 2.4 Gy per fraction. Fractions given once a day, 5 times a week for six weeks. All patients will receive standard concurrent chemotherapy.

For all patients, the dose to the PTV will be kept constant at 60 Gy in 30 fractions at 2.0 Gy per fraction , SIBV will be kept constant at 72 Gy in 30 fractions at 2.4 Gy per fraction. Fractions given once a day, 5 times a week for six weeks. All patients will receive standard concurrent chemotherapy.

Progression free survival is defined as the time (in months) from the date of admission to the date of progression or last follow-up

To assess the pulmonary, oesophageal and cardiac grade 3 or 4 toxicity occurring up to 3 and 6 months after radiotherapy, according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0.

ORR is defined as the proportion of participants with an overall response of complete response (CR) of any duration, partial response (PR) of any duration for a minimum of 3 months from start of treatment. Per RECIST, CR: disappearance of all target lesions, all non-target lesions, and no new lesion; PR: a >=30% decrease in the sum of the longest dimensions of the target lesions (TLs) taking as a reference the baseline sum, no unequivocal progression of non-TLs, and no new lesions; progressive disease (PD), a >=20% increase in TLs, clearly worsening of non-TLs, or emergence of new lesions; stable disease (SD): no change or small changes that do not meet previously given criteria for CR, PR or PD.

Overall survival is defined as the time (in months) from the date of admission to the date of death from any cause or last follow-up

Inclusion Criteria: Histologically confirmed NSCLC, inoperable stages IIA-IIIB, according to American Joint Committee on Cancer （AJCC）Cancer Stage 7th Performance status 0 to 2, ≤5% weight loss within the past 6 months A forced expiratory volume at 1 second of ≥ 1 L Life expectancy > 3 months No invasion of large vessels, heart, esophagus, spinal cord. Based on conformal treatment planning, the volume of lung at or exceeding 20 Gy (V20) must have been≤30%, the mean esophagus dose≤34 Gy, and the volume of esophagus exceeding 55 Gy (V55)≤30% Tolerable and agree for Intensity-Modulated Radiation Therapy（IMRT） and concurrent chemoradiotherapy Without severe other diseases Informed consent Exclusion Criteria: Had received prior thoracic radiotherapy Supraclavicular lymph node metastasis, pleural or pericardial effusions, and superior vena cava syndrome Pregnant and lactating women Serious complications Other primary malignancies

Yang W, Zeng B, Qiu Y, Tan J, Xu S, Cai Y, Zhou Y, Liu Z, Luo J, Wang H. A Dosimetric Comparison of Dose Escalation with Simultaneous Integrated Boost for Locally Advanced Non-Small-Cell Lung Cancer. Biomed Res Int. 2017;2017:9736362. doi: 10.1155/2017/9736362. Epub 2017 May 28.