Volumetric-modulated arc therapy (VMAT) has emerged as a promising radiation treatment technique. One of the challenges in VMAT planning for lung carcinoma is the lack of consistency among different institutions with respect to what is considered an acceptable treatment plan in terms of target coverage and doses to the organs at risk (OAR). Additionally, the accuracy of dose calculations in the presence of heterogeneous medium (i.e. air) is another challenge in lung VMAT planning. Our objective is to develop an institutional criteria for non-stereotactic body radiotherapy (non-SBRT) lung treatment plans by evaluating the dosimetric impact of plan normalisation and dose calculation algorithms, including the Anisotropic Analytical Algorithm (AAA), AcurosXB (AXB) and Monte Carlo (MC) simulation, on VMAT plans for non-small cell lung cancer (NSCLC).

The CT dataset of 20 patients with NSCLC was randomly selected to ensure a spectrum of target sizes and locations. All treatment planning was accomplished with 2–3 VMAT arcs and a prescription of 60 Gy in 30 fractions. Two plan normalisation methods were employed: (i) planning target volume (PTV) V100% = 95% and (ii) PTV V95% = 95%.

All three dose calculation algorithms revealed heterogeneous and conformal plans irrespective of plan normalisations. The PTV and OARs dose–volume constraints were met using both normalisation methods. However, we observed that AAA overestimated the minimum PTV doses by 2–5% regardless of plan normalisation. The mean PTV-V100% was lower for AAA in comparison with AXB and MC algorithms.

VMAT is an effective radiotherapy technique for achieving greater target dose conformity, heterogeneity and dose fall-off from the PTV for the treatment of NSCLC. The results of this study can provide the basis for the development of local plan acceptability criteria for NSCLC VMAT plans, and the clinical implementation can be achieved with minimal or no imposition on resources and time constraints. Occasionally, plan normalisation of PTV-V95% = 95% may be required to ensure that the OAR dose tolerances are not exceeded.

Carcinomatous meningitis with metastases to the spinal cord [intramedullary spinal cord (IMSC)] is very rare, and a quick intervention to management of these patients is important in preventing neurological deterioration.

We report a case of IMSC metastases from a stage IV non-small cell lung carcinoma in a 57-year-old man who presented with Brown-Sequard syndrome along with multiple brain metastases with associated carcinomatous meningitis and managed with urgent palliative external beam radiation therapy.

A quick, short course of palliative radiation therapy for inoperable patients with IMSC metastases provides improvement in neurological function in the management of these oncologic emergencies in patients with short survival times.

To identify treatment outcome, dose uniformity, treatment time, toxicity among 3D conformal therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT) for non-small-cell lung cancer (NSCLC) based on literature review.

A literature search was conducted using PubMed/MEDLINE, BMC—part of Springer Nature, Google Scholar and iMEDPub Ltd with the following keywords for filtering: 3D-CRT, IMRT, VMAT, lung cancer, local control and radiobiology. A total of 14 publications were finally selected for the comparison of 3D-CRT, IMRT and VMAT to determine which technique is superior or inferior among these three.

Compared to 3D-CRT, IMRT delivers more precise treatment, has better conformal dose coverage to planning target volume (PTV) that covers gross tumour with microscopic extension, respiratory tumour motion and setup margin. 3D-CRT has large number of limitations: low overall survival (OS), large toxicity, secondary malignancies.

It is difficult to choose the best technique for treating NSCLC due to patient conditions and technique availability. A high-precision treatment may improve tumour control probability (TCP) and patient’s quality of life. VMAT, whether superior or not, needs more clinical trials to treat NSCLC and requires longer dose optimisation time with the greatest benefit of rapid treatment delivery, improved patient comfort, reduced intrafraction motion and increased patient throughput compared to IMRT and 3D-CRT.

Treatment of metachronous second primary non-small cell lung cancer (NSCLC) in patients already treated with definitive radiotherapy is a matter of debate, since most patients are excluded from surgical treatment, which remains a therapeutic standard for patients with isolated lung masses. Salvage chemotherapy or immunotherapy alone offers a low probability of disease control. The option of re-irradiation often remains the only viable, but the risks of severe acute or late toxicities affecting the surrounding normal tissues make this a real clinical challenge.

From January 2015 to April 2018, five patients (male/female: 4/1; age 54–81 years, median 68) with previously irradiated NSCLC presented with a second primary lung tumour.

A partial response was seen in four patients, one complete responses in the fifth. The toxicity was low: two patients experienced a grade 2 asymptomatic radiation pneumonitis after 6 and 12 months from the end of stereotactic body radiation therapy, resolved with cortisone therapy. No acute or late oesophageal or cardiac toxicity was found.

In this work, we present our initial experience about the use of stereotactic radiotherapy technique in already irradiated patients. We reported a local disease control in all cases with an acceptable toxicity.

This study aimed to compare intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) regarding plan quality and healthy lung sparing, in stage III non-small cell lung cancer (NSCLC) patients.

The plans of 60 patients were allocated either to the IMRT (n=30) or the VMAT (n=30) group. The dose prescribed to the planning target volume (PTV) was evaluated at the 95% level and the mean lung dose (MLD) and the healthy lung receiving 5, 10 and 20 Gy (V5, V10 and V20, respectively) were analysed. The normal tissue complication probability (NTCP) for radiation pneumonitis was calculated with the Lyman–Kutcher–Burman model.

Both techniques achieved comparable results for target coverage (V95%=97·87 versus 97·18%, p>0·05) and homogeneity. The MLD (15·57 versus 16·98 Gy, p>0·05), V5 (60·35 versus 67·25%, p>0·05) and V10 (45·22 versus 53·14%, p=0·011) were lower for IMRT, whereas VMAT reduced V20 (26·44 versus 25·90%, p>0·05). The NTCP for radiation pneumonitis was higher for VMAT, but no statistical significance was observed (11·07 versus 12·75, p>0·05).

Both techniques seemed suitable for NSCLC treatment, but IMRT presented better results regarding lung sparing thus being beneficial in reducing the risk of radiation-induced pneumonitis.