Concurrent chemoradiotherapy (CCRT) has become the standard of care for patients with unresectable stage III non–small cell lung cancer (NSCLC). The comparative merits of two widely used regimens: carboplatin/paclitaxel (PC) and cisplatin/etoposide (PE), each with concurrent radiotherapy, remain largely undefined. Records for consecutive patients with stage III NSCLC treated with PC or PE and ≥60 Gy chest radiotherapy between 2000 and 2011 were reviewed for outcomes and toxicity. Survival was estimated using the Kaplan–Meier method and Cox modeling with the Wald test. Comparison across groups was done using the student's t and chi‐squared tests. Seventy‐five (PC: 44, PE: 31) patients were analyzed. PC patients were older (median 71 vs. 63 years; P = 0.0006). Other characteristics were comparable between groups. With PE, there was significantly increased grade ≥3 neutropenia (39% vs. 14%, P = 0.024) and thrombocytopenia (10% vs. 0%, P = 0.039). Radiation pneumonitis was more common with PC (66% vs. 38%, P = 0.033). Five treatment‐related deaths occurred (PC: 3 vs. PE: 2, P = 1.000). With a median follow‐up of 51.6 months, there were no significant differences in relapse‐free survival (median PC 12.0 vs. PE 11.5 months, P = 0.700) or overall survival (median PC 20.7 vs. PE 13.7 months; P = 0.989). In multivariate analyses, no factors predicted for improved survival for either regimen. PC was more likely to be used in elderly patients. Despite this, PC resulted in significantly less hematological toxicity but achieved similar survival outcomes as PE. PC is an acceptable CCRT regimen, especially in older patients with multiple comorbidities.

Differentiating between radiation necrosis and true tumour progression after radiotherapy is challenging due to overlapping imaging appearances. This review outlines useful techniques and imaging features for making this distinction, as well as potential pitfalls. Both radiation necrosis and true tumour progression commonly manifest as peripherally enhancing lesions on post‐contrast T1‐weighted imaging, but the enhancing rim should be thin in radiation necrosis, while more discrete nodular enhancement suggests active tumour. Other features on post‐contrast MRI that suggest radiation necrosis include enhancing lesions across anatomical boundaries, clustering of enhancing lesions and a change in lesion shape. Central diffusion restriction corresponding to the central necrotic area favours radiation necrosis, but there are potential pitfalls to be aware of, including hypercellular tumours, coagulative necrosis due to bevacizumab and intra‐lesional haemorrhage. Radiation necrosis typically results in small, clustered foci of magnetic susceptibility on susceptibility‐sensitive sequences, and the absence of such foci should raise concern for active tumour. When uncertainty remains, ancillary techniques such as MR perfusion and amino acid PET can improve confidence. Atypical appearances of radiation necrosis can occur, for example, cystic radiation necrosis or radiation necrosis occurring after radiotherapy to adjacent structures. It is also important for the radiologist to be aware of additional factors that may increase the likelihood of either radiation necrosis or tumour necrosis or influence patient management.

Purpose: Shorter hypofractionated radiation therapy (HF-RT) schedules may have radiobiological, patient convenience and healthcare resource advantages over conventionally fractionated radiation therapy (CF-RT) in glioblastoma (GBM). We report outcomes of young, fit GBM patients treated with HF-RT and CF-RT during the COVID-19 pandemic, and a meta-analysis of HF-RT literature in this patient subgroup. Methods: Hospital records of patients with IDH-wildtype GBM treated with HF-RT (50 Gy/20 fractions) and CF-RT (60 Gy/30 fractions) between January 2020 and September 2021 were reviewed. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Univariable analysis was performed using Cox regression analysis. A systematic search and meta-analysis of studies from January 2000 to January 2022 was performed. Results: 41 patients were treated (HF-RT:15, CF-RT:26). For both HF-RT and CF-RT groups, median age was 58 years and 80–90% were ECOG 0–1. There were more methylated tumours in the HF-RT group. All patients received concurrent/adjuvant temozolomide. At 19.2 months median follow-up, median OS was 19.8 months and not-reached for HF-RT and CF-RT (p = 0.5), and median PFS was 7.7 and 5.8 months, respectively (p = 0.8). HF-RT or CF-RT did not influence OS/PFS on univariable analysis. Grade 3 radionecrosis rate was 6.7% and 7.7%, respectively. 15 of 1135 studies screened from a systematic search were eligible for meta-analysis. For studies involving temozolomide, pooled median OS and PFS with HF-RT were 17.5 and 9.9 months (927 and 862 patients). Studies using shortened HF-RT schedules reported 0–2% Grade 3 radionecrosis rates. Conclusion: HF-RT may offer equivalent outcomes and reduce treatment burden compared to CF-RT in young, fit GBM patients.