ASTRO Radiation Therapy Summary of the ASCO Guideline on Management of Stage III Non-Small Cell Lung Cancer

Anti-PD1 based precision induction therapy in unresectable stage III non-small cell lung cancer: a phase II umbrella clinical trial

The efficacy and safety of induction-immunotherapy followed by surgery for unresectable Stage III non-small cell lung cancer (NSCLC) remain challenging. In this open-label, single-center, phase II clinical umbrella trial (ChiCTR2000035367), 100 unresectable Stage III NSCLC patients are enrolled. Patients with PD-L1 expression ≥ 50% but contraindications to anti-angiogenic therapy receive immuno-monotherapy. Patients with PD-L1 expression ≥ 1% and no contraindications to anti-angiogenic therapy receive immunotherapy plus anti-angiogenesis therapy. Patients with PD-L1 expression between 1% and 49%, contraindications to anti-angiogenic therapy, or negative/unknown PD-L1 expression receive chemoimmunotherapy. The primary endpoint is the major pathological response (MPR) rate. Among 47 surgically-treated patients, the MPR rate is 61.7% (95% confidence interval [CI]: 46.4%-75.5%), achieving the prespecified endpoint. For secondary endpoints, the objective response rate for all patients is 54.0% (95% CI: 43.7-64.0). The median event-free survival is 29.9 months (95% CI: 17.0-42.7). Most common adverse event is anemia (49.0%). Exploratory transcriptomic analyses reveal Bone Marrow Stromal Cell Antigen 1 (BST1) as a promising biomarker for response to chemoimmunotherapy. Generally, for unresectable stage III NSCLC patients, anti-PD1 based induction-therapy according to PD-L1 expression and contraindication to antiangiogenic therapy followed by surgery is a feasible option.

Network meta-analysis on the efficacy and safety of management for resectable stage IIIA-N2 non-small cell lung cancer

BACKGROUND

There is controversy regarding the optimal treatment for stage IIIA-N2 non-small cell lung cancer (NSCLC). We aimed to address this crucial issue through a frequentist network meta-analysis.

METHODS

We conducted a literature database search for randomized controlled trials comparing the following treatment modalities before March 1st, 2023: surgery, radiotherapy, chemotherapy, targeted therapy, immunotherapy, and various combinations of these treatments. Summary data on overall survival (OS) and treatment-related deaths (trDeath) were analyzed using frequentist methods.

RESULTS

Twenty-two randomized controlled trials (RCTs) with 3269 participants were included, covering 17 treatment regimens. In terms of overall survival, surgery followed by adjuvant targeted therapy (S-T), neoadjuvant targeted therapy followed by surgery and adjuvant targeted therapy (T-S-T), and neoadjuvant chemotherapy followed by surgery and adjuvant chemotherapy (C-S-C) were relatively more advantageous than other treatment regimens. Overall, S-T is the most likely treatment option to prolong OS, with a 59.8% likelihood, while immunotherapy plus chemotherapy followed by surgery and adjuvant chemotherapy (IC-S-C) demonstrates good safety.

CONCLUSION

S-T and T-S-T treatments have the greatest potential to be the optimal overall survival treatments for stage IIIA-N2 NSCLC patients with positive driver genes, demonstrating significant clinical application prospects. While for patients with negative driver genes, C-S-C treatments benefit the most. The protocol was registered in the Prospective Register of Systematic Reviews, PROSPERO (CRD42022372711).

Development of brain metastases in patients managed with non-curative thoracic radiotherapy for stage II/III non-small cell lung cancer

BACKGROUND

This retrospective study analyzed the incidence of subsequent brain metastases after palliative radiotherapy or chemoradiation in patients with stage II/III non-small cell lung cancer (NSCLC). Risk factors for brain metastases development and survival after diagnosis were evaluated.

METHODS

Different baseline parameters including but not limited to age, stage and target volume size were assessed. Outcomes were abstracted from electronic health records. Uni- and multivariate tests were performed.

RESULTS

The study included 102 patients and found an actuarial risk of brain metastases of 15% (standard error ± 4) at one year and 20% (± 5) at two years. The maximum time interval was 15 months from start of radiation treatment. A non-significant survival difference was observed (median 12 months without versus 8.3 months with brain metastases, p = 0.21). Incidence was higher in patients with N2/3 stage, larger planning target volume size, and younger age (univariately significant factors). Trends were seen for stage III and adenocarcinoma histology. The multivariate analysis confirmed age as the most important risk factor.

CONCLUSION

The risk of brain metastases development was comparable to that reported in studies of curative chemoradiation. All events occurred within 15 months of follow-up, suggesting that long-term surveillance imaging may not be warranted. Patients younger than 60 years had a very high risk of brain metastases development.

Surgically resectable nonsmall cell lung cancer: a contemporary approach

New treatment paradigms for resectable nonsmall cell lung cancer (NSCLC), with an emphasis on personalised care and a multidisciplinary approach, have significantly improved patient outcomes. The incorporation of immune checkpoint inhibitors into neoadjuvant, perioperative and adjuvant treatment algorithms is reshaping the standard of care for resectable NSCLC. Adjuvant targeted therapy trials have also paved the way for a much-needed personalised approach for patients with actionable genomic alterations. Innovative surgical techniques and judicious use of postoperative radiotherapy may mitigate the toxicity associated with a multimodality approach. Amid the many new treatment options, questions remain about the best approach to consider for each patient. Measurement of minimal residual disease and achievement of pathological complete response are emerging biomarkers of interest to help further refine treatment selection. This review summarises the current management of resectable NSCLC, focusing on ongoing and recent advances in surgical approaches, the role of postoperative radiotherapy and the rapidly changing field of systemic therapies.

Dosimetric comparison of nodal clinical target volume for locally advanced non‑small cell lung cancer: Options for geometric expansion vs. lymph node stations

The purpose of the present retrospective study was to evaluate whether dosimetric differences existed in nodal clinical target volume (CTV) using options for geometric expansion and lymph node (LN) stations based on the European Society for Radiotherapy and Oncology guideline for locally advanced non-small cell lung cancer (NSCLC). In the treatment planning computed tomographic images of 17 patients with cT4N2M0 NSCLC, nodal CTVs were contoured based on the guideline options of: i) Geometric expansion, with CTV including the nodal gross tumor volume plus 5 mm margin; and ii) LN stations, with CTV including the affected LN stations. Treatment planning of 60 Gy in 30 fractions was performed using volumetric modulated arc therapy; Dmean was the mean irradiated dose to the structure; and VnGy was the volume of the structure receiving ≥n Gy. Dose-volume parameters were compared between the two options. Consequently, the option of geometric expansion was associated with a significantly lower V60Gy and Dmean of the esophagus, V20Gy, V5Gy and Dmean of the lungs, and Dmean of the heart than the option of LN stations in all patients (P=0.017, P<0.001, P<0.001, P<0.001, P<0.001 and P=0.029, respectively). For the V20Gy of the lungs, the 8 patients (47%) with LN metastases in stations 2 or 3 had significantly larger differences in the values between the two options than the 9 patients (53%) without those metastases; the median values of the difference of V20Gy of the lungs between the two options were 2.8% (range, 0.2 to 9.6%) with LN metastases in stations 2 or 3 and 0.5% (range, -0.2 to 5.0%) without these metastases (P=0.027). In conclusion, using the option for geometric expansion might help reduce the V60Gy and Dmean of the esophagus, V20Gy, V5Gy and Dmean of the lungs, and Dmean of the heart in all patients, and the V20Gy of the lungs in patients with LN metastases in stations 2 or 3.

Contemporary Strategies: Incorporating Immunotherapy into Stage 3 Non-small Cell Lung Cancer Treatment

Stage 3 non-small cell lung cancer (NSCLC) exhibits significant diversity, making it challenging to define an optimal treatment. A collaborative multidisciplinary approach is essential in crafting individualized treatments. Previously, targeted therapies and immunotherapies were commonly used to treat patients with advanced and metastatic lung cancer. Such treatments are now being extended to individuals considered surgery, as well as patients once considered unsuitable for surgery. These changes have increased surgical success and substantially reduced postoperative recurrence. However, the possibility of severe adverse effects from immunotherapy can deter some patients from performing surgery. It is essential to carefully explore the clinical traits and biomarkers of patients who may benefit the most from immunotherapy, and patients for whom immunotherapy should not be prescribed. In summary, it's crucial to effectively integrate the latest immunotherapy in treating stage 3 NSCLC patients, thereby increasing their opportunities for surgical intervention, and ensuring they receive the best possible care.

Systematic endoscopic staging of mediastinum to guide radiotherapy planning in patients with locally advanced non-small-cell lung cancer (SEISMIC): an international, multicentre, single-arm, clinical trial

BACKGROUND

Systematic mediastinal lymph node staging by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) improves accuracy of staging in patients with early-stage non-small-cell lung cancer (NSCLC). However, patients with locally advanced NSCLC commonly undergo only selective lymph node sampling. This study aimed to determine the proportion of patients with locally advanced NSCLC in whom systematic endoscopic mediastinal staging identified PET-occult lymph node metastases, and to describe the consequences of PET-occult disease on radiotherapy planning.

METHODS

This prospective, international, multicentre, single-arm, international study was conducted at seven tertiary lung cancer centres in four countries (Australia, Canada, the Netherlands, and the USA). Patients aged 18 years or older with suspected or known locally advanced NSCLC underwent systematic endoscopic mediastinal lymph node staging before combination chemoradiotherapy or high-dose palliative radiotherapy. The primary endpoint was the proportion of participants with PET-occult mediastinal lymph node metastases shown following systematic endoscopic staging. The study was prospectively registered with Australian New Zealand Clinical Trials Registry, ACTRN12617000333314.

FINDINGS

From Jan 30, 2018, to March 23, 2022, 155 patients underwent systematic endoscopic mediastinal lymph node staging and were eligible for analysis. 58 (37%) of patients were female and 97 (63%) were male. Discrepancy in extent of mediastinal disease identified by PET and EBUS-TBNA was observed in 57 (37% [95% CI 29-44]) patients. PET-occult lymph node metastases were identified in 18 (12% [7-17]) participants, including 16 (13% [7-19]) of 123 participants with clinical stage IIIA or cN2 NSCLC. Contralateral PET-occult N3 disease was identified in nine (7% [2-12]) of 128 participants staged cN0, cN1, or cN2. Identification of PET-occult disease resulted in clinically significant changes to treatment in all 18 patients. In silico dosimetry studies showed the median volume of PET-occult lymph nodes receiving the prescription dose of 60 Gy was only 10·1% (IQR 0·1-52·3). No serious adverse events following endoscopic staging were reported.

INTERPRETATION

Our findings suggests that systematic endoscopic mediastinal staging in patients with locally advanced or unresectable NSCLC is more accurate than PET alone in defining extent of mediastinal involvement. Standard guideline-recommended PET-based radiotherapy planning results in suboptimal tumour coverage. Our findings indicate that systematic endoscopic staging should be routinely performed in patients with locally advanced NSCLC being considered for radiotherapy to accurately inform radiation planning and treatment decision making in patients with locally advanced NSCLC.

FUNDING

None.

Evidence-based clinical recommendations for hypofractionated radiotherapy: exploring efficacy and safety - Part 2. Lung (non-small cell lung cancer)

Several recent studies have investigated the use of hypofractionated radiotherapy (HFRT) for various cancers. However, HFRT for non-small cell lung cancer (NSCLC) with or without concurrent chemotherapy is not yet widely used because of concerns about serious side effects and the lack of evidence for improved treatment results. Investigations of HFRT with concurrent chemotherapy in NSCLC have usually been performed in single-arm studies and with a small number of patients, so there are not yet sufficient data. Therefore, the Korean Society for Radiation Oncology Practice Guidelines Committee planned this review article to summarize the evidence on HFRT so far and provide it to radiation oncology clinicians. In summary, HFRT has demonstrated promising results, and the reviewed data support its feasibility and comparable efficacy for the treatment of locally advanced NSCLC. The incidence and severity of esophageal toxicity have been identified as major concerns, particularly when treating large fraction sizes. Strategies, such as esophagus-sparing techniques, image guidance, and dose constraints, may help mitigate this problem and improve treatment tolerability. Continued research and clinical trials are essential to refine treatment strategies, identify optimal patient selection criteria, and enhance therapeutic outcomes.

Comparative assessment of radiation therapy-induced vasculitis using [18F]FDG-PET/CT in patients with non-small cell lung cancer treated with proton versus photon radiotherapy

PURPOSE

To assess radiation therapy (RT)-induced vasculitis in patients with non-small cell lung cancer (NSCLC) by examining changes in the uptake of 18F-fluoro-D-deoxyglucose ([18F]FDG) by positron emission tomography/computed tomography (PET/CT) images of the ascending aorta (AA), descending aorta (DA), and aortic arch (AoA) before and after proton and photon RT.

METHOD

Thirty-five consecutive locally advanced NSCLC patients were definitively treated with proton (n = 27) or photon (n = 8) RT and concurrent chemotherapy. The patients were prospectively enrolled to undergo [18F]FDG-PET/CT imaging before and 3 months after RT. An adaptive contrast-oriented thresholding algorithm was applied to generate mean standardized uptake values (SUVmean) for regions of interest (ROIs) 3 mm outside and 3 mm inside the outer perimeter of the AA, DA, and AoA. These ROIs were employed to exclusively select the aortic wall and remove the influence of blood pool activity. SUVmeans before and after RT were compared using two-tailed paired t-tests.

RESULTS

RT treatments were associated with increased SUVmeans in the AA, DA, and AoA-1.9%, 0.3%, and 1.3% for proton and 15.8%, 9.5%, and 15.5% for photon, respectively. There was a statistically significant difference in the ∆SUVmean (post-RT SUVmean - pre-RT SUVmean) in patients treated with photon RT when compared to ∆SUVmean in patients treated with proton RT in the AA (p = 0.043) and AoA (p = 0.015). There was an average increase in SUVmean that was related to dose for photon patients (across structures), but that was not seen for proton patients, although the increase was not statistically significant.

CONCLUSION

Our results suggest that patients treated with photon RT for NSCLC may exhibit significantly more RT-induced inflammation (measured as ∆SUVmean) in the AA and AoA when compared to patients who received proton RT. Knowledge gained from further analyses in larger cohorts could aid in treatment planning and help prevent the significant morbidity and mortality associated with RT-induced vascular complications.

TRIAL REGISTRATION

NCT02135679.

Exploring the past, present, and future of postoperative radiotherapy for N2 stage non-small cell lung cancer

Despite conventionally applied postoperative radiotherapy (PORT) in pathological N2 (pN2) stage non-small cell lung cancer (NSCLC) considering high locoregional recurrence, its survival benefit has been a continuous topic of debate. Although several randomized clinical trials have been conducted, many of them have been withdrawn or analyzed without statistical significance due to slow accrual, making it difficult to determine the efficacy of PORT. Recently, the results of large-scale randomized clinical trials have been published, which showed some improvement in disease-free survival with PORT, but finally had no impact on overall survival. Based on these results, it was expected that the debate over PORT in pN2 patients with NSCLC would come to an end. However, since pN2 patients have different clinicopathologic features, it has become more important to carefully select the patient population who will benefit from PORT. In addition, given the development of systemic treatments such as molecular-targeted therapy and immunotherapy, it is crucial to evaluate whether there is any benefit to PORT in the midst of these recent changes. Therefore, determining the optimal treatment approach for NSCLC pN2 patients remains a complex issue that requires further research and evaluation.