Provider decision regret-a useful method for analysis of palliative thoracic re-irradiation for lung cancer?

Prospective randomized clinical studies involving reirradiation: update of a systematic review

BACKGROUND

Reirradiation is a potentially useful option for many patients with recurrent cancer, aiming at cure or symptom palliation, depending on disease/recurrence type and stage. The purpose of this follow-up study to a previous review from 2016 was to summarize all recently published randomized trials. Points of interest again included identifcation of methodological strengths and weaknesses, practice-changing results, and open questions.

MATERIAL AND METHODS

Systematic review of trials published between 2015 and February 2023.

RESULTS

We reviewed 7 additional trials, most of which addressed reirradiation of head and neck or brain tumours. The median number of patients was 60. Mirroring the previous review, trial design, primary endpoints and statistical hypotheses varied widely. The updated results only impact on decision making for reirradiation of nasopharynx cancer and glioma. Patients with one of these diseases, as well as other head and neck cancers, may benefit from reirradiation-induced local control, e.g. in terms of progression-free survival. For the first time, hyperfractionated radiotherapy emerged as preferred option for recurrent, inoperable nasopharynx cancer. Despite better therapeutic ratio with hyperfractionation, serious toxicity remains a concern after high cumulative total doses. Randomized trials are still lacking for prostate cancer and other sites.

CONCLUSION

Multicentric randomized trials on reirradiation are feasible and continue to refine the current standard of care for recurrent disease after previous radiotherapy. Ongoing prospective studies such as the European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer (ESTRO-EORTC) observational cohort ReCare (NCT: NCT03818503) will further shape the clinical practice of reirradiation.

Re-Irradiation for Locally Recurrent Lung Cancer: A Single Center Retrospective Analysis

The treatment of locally recurrent lung cancer is a major challenge for radiation-oncologists, especially with data on high-dose reirradiation being limited to small retrospective studies. The aim of the present study is to assess overall survival (OS) for patients with locally recurrent lung cancer after high-dose thoracic reirradiation. Thirty-nine patients who were re-irradiated for lung cancer relapse between October 2013 and February 2019 were eligible for the current retrospective analysis. All patients were re-irradiated with curative intent for in-field tumor recurrence. The diagnostic work-up included a mandatory ¹⁸F-FDG-PET-CT scan and—if possible—histological verification. The ECOG was ≤2, and the interval between initial and second radiation was at least nine months. Thirty patients (77%) had non-small cell lung cancer (NSCLC), eight (20%) had small cell lung cancer (SCLC), and in one patient (3%) histological confirmation could not be obtained. More than half of the patients (20/39, 51%) received re-treatment with dose differentiated accelerated re-irradiation (DART) at a median interval of 20.5 months (range: 6–145.3 months) after the initial radiation course. A cumulative EQD₂ of 131 Gy (range: 77–211 Gy) in a median PTV of 46 mL (range: 4–541 mL) was delivered. Patients with SCLC had a 3 mL larger median re-irradiation volume (48 mL, range: 9–541) compared to NSCLC patients (45 mL, range: 4–239). The median cumulative EQD2 delivered in SCLC patients was 84 Gy (range: 77–193 Gy), while NSCLC patients received a median cumulative EQD2 of 135 Gy (range: 98–211 Gy). The median OS was 18.4 months (range: 0.6–64 months), with tumor volume being the only predictor (p < 0.000; HR 1.007; 95%-CI: 1.003–1.012). In terms of toxicity, 17.9% acute and 2.6% late side effects were observed, with a toxicity grade >3 occurring in only one patient. Thoracic high dose reirradiation plays a significant role in prolonging survival, especially in patients with small tumor volume at recurrence.

Impact of reirradiation, chemotherapy, and immunotherapy on survival of patients with recurrent lung cancer: A single-center retrospective analysis

Background

Given the limited curative treatment options for recurrent lung cancer patients, the aim of our retrospective study was to investigate whether these patients would benefit in terms of overall survival (OS) by adding immunotherapy to high‐dose reirradiation.

Materials and methods

Between 2013 and 2019, 47 consecutive patients with in‐field tumor recurrence underwent high‐dose thoracic reirradiation at our institute. Twenty patients (43%) received high‐dose reirradiation only, while 27/47 (57%) additionally had systemic therapy (immunotherapy and/or chemotherapy). With the exception of one patent, the interval between first and second radiation was at least 9 months. All patients had an Eastern cooperative oncology group ≤2. The diagnostic work‐up included a mandatory fluorodeoxyglucose‐positron emission tomography‐computed tomography scan and histological verification. The primary endpoint was OS after completion of the second course of irradiation.

Results

In the whole cohort of 47 patients, the median overall survival (mOS) after reirradiation was 18.9 months (95% confidence interval [CI] 16.5–21.3 months), while in the subgroup of 27 patients who received additional systemic treatment after reirradiation, mOS amounted to 21.8 months (95% CI 17.8–25.8 months). Within this group the comparison between reirradiation combined with either immunotherapy (n = 21) or chemotherapy (n = 6) revealed a difference in OS, which was in favor of the first (log‐rank p value = 0.063). Three patients (11%) experienced acute side effects and one (4%) showed a late hemorrhage grade 3.

Conclusion

Patients who received immunotherapy and reirradiation lived longer than those who did not receive immunotherapy.