ESTRO 2024 Congress report
By the ESTRO lung focus group
This session was packed full of exciting papers across a range of thoracic malignancy scenarios. First was, incoming ESTRO president Matthias Guckenberger, who presented the final analysis of the European Thoracic Oncology Platform (ETOP) CHESS trial. The CHESS study examined the use of intensive immunotherapy, chemotherapy, radiotherapy and surgery for synchronous oligo-metastatic non-small-cell lung cancer (NSCLC) in patient with one to three metastases. Patients received induction chemoimmunotherapy and stereotactic ablative radiotherapy (SABR) to all metastatic sites. Patients who did not progress went on to receive definitive treatment at the primary tumour site (radiotherapy or surgery). The CHESS trial did not meet its primary endpoint; only 14 patients of 42 enrolled reached 12 months of progression-free survival (PFS) (the one-year PFS rate was 45%, and the one-year overall survival rate was 75%). Given a favourable safety toxicity finding, the ETOP investigators are taking the concept forward to a subsequent cohort study, which will add tremelimumab to the investigation regimen.
Next, Tobias Finazzi presented the findings regarding quality assurance (QA) and interim safety of the use of immune-modulatory radiotherapy in resectable stage III(N2) NSCLC from the Swiss Group for Clinical Cancer Research (SAKK) 16/18 trial. This study enrols patients to neo-adjuvant chemotherapy, then randomises patients to three different dose and fractionation regimens of radiotherapy alongside durvalumab, followed by surgery and adjuvant durvalumab. Good QA compliance by participating centres was reported with no early worrying safety signals.
Fabio Arcidiacono presented the five-year survival and safety outcomes of the study into the use of SABR in newly diagnosed and recurrent locally advanced NSCLC patients unfit for concurrent radio-chemotherapy (START-NEW-ERA). This study delivered a five-fraction SABR regimen equivalent to 60Gy in 30 fractions, with or without durvalumab, to patients with centrally located NSCLC who could not receive chemoradiotherapy. The overall five-year survival rate was impressive at 46%, with median survival at 53 months, and no patients experienced ≥ grade 3 toxicity.
Presenting the SYSTEMS-2 study of radiotherapy dose escalation (20Gy in five fractions versus 36Gy in six fractions) for pain control in patients with mesothelioma, Miranda Ashton reported that there was no difference in the primary endpoint of pain relief at five weeks. After this report, Marloes Duijm presented a toxicity analysis of high-dose re-irradiation of in-field recurrent lung cancer in a prospective trial. In summary, no ≥ grade 5 toxicity was observed and a median overall survival of 30 months was noted. The accumulated DMax dose constraints of 75Gy3 to the spine, 100Gy3 to the oesophagus and 110Gy3 to the tracheobronchial tree were considered feasible, and the accumulated Dmean and V20 of the lungs were associated with grade 2-3 radiation pneumonitis. These data provided useful dose constraint parameters of re-irradiation.
The final presentation in the session was delivered by Wenhan Huang, who spoke regarding a stage III trial of moderately hypofractionated (60Gy in 20 fractions) versus conventional radiotherapy (60Gy in 30 fractions) in stage III NSCLC. The radiation was delivered by helical tomotherapy and with concurrent platinum-based chemotherapy. Both arms were followed by two cycles of consolidation chemotherapy. The median survival rate was significantly higher in the hypofractionated arm than that of conventional radiotherapy (41 months versus 30 months, p=0.022). The authors reported no significant increase in toxicity in the hypofractionated arm. These results made this an exciting potential strategy in stage III NSCLC.
Professor Gerry Hanna
Marie Curie chair of radiation oncology
Trinity College Dublin
Ireland
ESTRO lung focus group