Radiation Dose Escalation in Stage III Non-Small-Cell Lung Cancer

Clinical management of stage III non-small cell lung cancer in India: An expert consensus statement

Non-small cell lung cancer (NSCLC) is considered the most common type of lung cancer (>80% of all lung cancers); patients are often diagnosed at advanced stages of the disease. The management of NSCLC is considered challenging owing to variations in size, an extension of the tumors, involvement patterns, and classification. Although adequate literature and guidelines are available on the management of NSCLC in several countries, an Indian perspective on stage III NSCLC management is lacking. We used the modified Delphi approach to form consensus statements. A thorough literature search was done. The authors then convened and deliberated over published literature, available guidelines, and clinical judgment. Recommendation statements were formed for different clinical scenarios. These statements were sent as a form of survey to other oncologists, and their responses were recorded and mentioned. Evidence-based statements were formed for diagnosing and managing stage III NSCLC. These recommendation statements cover various aspects-surgical, radiation, and medical treatment in various clinical scenarios including adjuvant, neoadjuvant, and consolidation therapies.

PET/CT for Target Delineation of Lung Cancer Before Radiation Therapy

In clinical routine of patients suffering from lung cancer, radiotherapy/radiation oncology represents one of the therapeutic hallmarks in the multimodal treatment besides or in combination with other local treatments such as surgery, but also systemic treatments such as chemotherapy, tyrosine kinase, and immune check-point inhibitors. Conventional morphological imagings such as CT or MR are commonly used for staging, response assessment, but also for radiotherapy planning. However, advanced imaging techniques such as PET do continuously get increasing access to clinical routine overcoming limitations of standard imaging techniques by visualizing and quantifying molecular processes such as glucose metabolism, which is also of relevance for radiotherapy planning. This review article summarizes the current place of radiotherapy within the treatment regimens of patients with lung cancer and elucidates current concepts of standard morphological imaging for staging and radiotherapy planning. Moreover, the place of PET-based radiotherapy planning in a clinical context is presented and current methodological/technical advances that do comprise a potential role for radiotherapy planning in lung cancer patients are discussed.

Durvalumab after Chemoradiotherapy for PD-L1 Expressing Inoperable Stage III NSCLC Leads to Significant Improvement of Local-Regional Control and Overall Survival in the Real-World Setting

Concurrent chemoradiotherapy (CRT) followed by maintenance treatment with the PD-L1 inhibitor durvalumab is a new standard of care for inoperable stage III NSCLC. The present study compares the oncological outcome of patients treated with CRT to those treated with CRT and durvalumab (CRT-IO) in the real-world setting. The analysis was performed based on the retro- and prospectively collected data of 144 consecutive inoperable stage III NSCLC patients treated between 2011-2020. Local-regional-progression-free-survival (LRPFS-defined as progression in the mediastinum, hilum and/or supraclavicular region at both sites and the involved lung), progression-free survival (PFS), and overall survival (OS) were evaluated from the last day of thoracic radiotherapy (TRT). Median follow-up for the entire cohort was 33.1 months (range: 6.3-111.8) and median overall survival was 27.2 (95% CI: 19.5-34.9) months. In the CRT-IO cohort after a median follow-up of 20.9 (range: 6.3-27.4) months, median PFS was not reached, LRPFS (p = 0.002), PFS (p = 0.018), and OS (p = 0.005) were significantly improved vs. the historical cohort of conventional CRT patients. After propensity-score matching (PSM) analysis with age, gender, histology, tumor volume, and treatment mode, and exact matching for T-and N-stage, 22 CRT-IO patients were matched 1:2 to 44 CRT patients. Twelve-month LRPFS, PFS, and OS rates in the CRT-IO vs. CRT cohort were 78.9 vs. 45.5% (p = 0.002), 60.0 vs. 31.8% (p = 0.007), and 100 vs. 70.5% (p = 0.003), respectively. This real-world analysis demonstrated that durvalumab after CRT led to significant improvement of local-regional control, PFS, and OS in PD-L1 expressing inoperable stage III NSCLC patients compared to a historical cohort.

Patterns and correlates of treatment failure in relation to isodose distribution in non-small cell lung cancer: An analysis of 1522 patients in the modern era

BACKGROUND AND PURPOSE

To examine the relationship between radiation dose and tumor control in limited stage non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

We searched a database of 1552 patients who received radiation therapy for non-metastatic NSCLC between 2000 and 2016. The primary endpoint was freedom from in-field failure.

RESULTS

Increasing BED correlated with decreasing estimated gross tumor volume-planning target volume expansion, and on multivariable analysis increasing BED was associated with an increased chance of field-edge failures (hazard ratio [HR] 1.032, 95% confidence interval [CI] 1.004-1.062, P = 0.027). Increasing BED also correlated with improved freedom from in-field failure on multivariable analysis (HR 0.978, 95% CI 0.964-0.993, P = 0.003), with the dose-response curve showing a sigmoidal relationship between increasing BED and freedom from in-field failure.

CONCLUSION

In this large study of patients treated in the modern era with varying dose fractionation regimens, higher BED was associated with improved freedom from in-field failure, and that this relationship appeared to be consistent with the classically described sigmoid shape. We also found that increased BED was associated with higher field-edge failures, implying that margin size may need to be further studied in patients receiving ablative regimens of radiation.

The effect of radiotherapy dose on survival in stage III non-small-cell lung cancer patients undergoing definitive chemoradiotherapy

BACKGROUND

In this study, we examined trends in the radiotherapy dose prescribed and the effect of dose escalation on survival in patients with stage III lung cancer.

MATERIALS AND METHODS

Radiation dose prescription patterns were analyzed for 38,848 patients in the National Cancer Database with clinical stage III disease who underwent concurrent chemoradiation between 2004 and 2011 to a dose between 57 and 80 Gy. Survival information was available for patients diagnosed from 2004 to 2006 (n = 12,024). Overall survival (OS) was estimated using Kaplan-Meier methods. Cox proportional hazard regression was used to estimate hazard ratios (HRs).

RESULTS

The percentage of patients treated to ≥ 64 Gy increased from 50% in 2004 to 62% in 2011 (P < .001). The 5-year OS was 12% for patients treated between 57 and 59.3 Gy, 14% for patients treated at 59.4 to 62.9 Gy, 16% for patients treated at 63 to 66 Gy and 66.1 to 73.9 Gy, and 13% for patients treated at 74 to 80 Gy (P < .0001). In multivariate analysis, the estimated HR (95% confidence interval) was 1.3 (1.1-1.6) for 57 to 59.3 Gy, 1.0 (0.9-1.2) for 59.4 to 62.9 Gy, 0.9 (0.9-1.2) for 63 to 66 Gy, 0.9 (0.8-1.1) for 66.1 to 73.9 Gy, and 1.0 (referent) for the 74 to 80 Gy cohort. There was no significant difference in the HR for the dose groups > 59.4 Gy compared with the 74 to 80 Gy cohort.

CONCLUSION

There was no improvement in OS with radiotherapy dose escalation beyond 59.4 Gy for patients with unresectable clinical stage III lung cancer treated with chemoradiation.

Advantages of proton therapy in non-small cell lung cancers

The advantage of proton therapy over conventional radiotherapy is enormous, with many clinical advantages. In this review, we summarized the important literature in the advantages of Proton Therapy in Non-small Cell Lung Cancers.