Abstract 5645
Background
Radiation induced CT changes may be apparent following completion of TRT. We sought to quantify differences in radiation-associated densities on serial CT scans of patients with ES-SCLC treated with TRT alone versus TRT followed by combined IPI and NIVO.
Methods
Between 2016 and 2018, patients at a single institution with ES-SCLC who achieved stable disease or better following initial treatment with platinum doublet chemotherapy were offered TRT and prescribed a total dose of 30Gy in 10 fractions targeting initially involved thoracic tumor sites. Combined IPI 3mg/kg and NIVO 1mg/kg was administered every 3 weeks for up to 4 doses. We evaluated an irradiated region of interest (ROI) within the lungs and a volume of lung (outside the Planning Target Volume) receiving > 20 Gy. Within the ROI, we calculated the Hounsfield unit (HU) mean for each patient prior to therapy and at subsequent follow-up CT thorax at least 60 days and closest to 120 days after commencing TRT. To quantify CT density change, we measured the difference in HU mean within the irradiated ROI before and after treatment.
Results
Seventeen patients enrolled on NCT03043599 received TRT followed by combined IPI/NIVO. Two additional patients received the same treatment off protocol. Eleven patients received TRT alone (no IPI/NIVO). The average increase in HU mean within 20Gy irradiated ROI before and after treatment was 9% (max 59%, min -19%) across the study cohort (n = 30). CTCAE grade 3 or higher pulmonary toxicity (N = 8 of 30) was significantly associated with increased CT density change within the ROI (mean 28% vs 2%, p = 0.001). Treatment with TRT and IPI/NIVO (N = 19 of 30) demonstrated a trend towards increased mean CT density change within the ROI compared to patients treated with TRT alone (mean 13% vs. 0%, p = 0.1).
Conclusions
Quantifying CT density change within irradiated lung parenchyma may offer a novel approach to predict radiation associated pulmonary toxicities. Measuring density changes across patient cohorts receiving TRT with novel systemic therapies may help to identify combined treatment strategies likely to be associated with diminished risk of toxicity.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Bristol-Myers Squibb.
Disclosure
S. Kim: Research grant / Funding (institution): Bristol-Myers Squibb. S.A. Rosenberg: Advisory / Consultancy: Novocure. J.E. Gray: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): AstraZeneca; Honoraria (self), Advisory / Consultancy: Celgene; Honoraria (self), Advisory / Consultancy: Takeda; Honoraria (self), Advisory / Consultancy: Janssen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Genentech; Honoraria (self), Advisory / Consultancy: Eli Lilly; Honoraria (self), Advisory / Consultancy: Triptych Health Partners. S.J. Antonia: Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy, Research grant / Funding (institution): Novartis; Advisory / Consultancy: Merck; Advisory / Consultancy: CBMG; Advisory / Consultancy: Boehringer Ingelheim; Advisory / Consultancy: AstraZeneca/MedImmune; Advisory / Consultancy: Memgen; Advisory / Consultancy: FLX Bio; Advisory / Consultancy: Nektar; Advisory / Consultancy: Venn. B. Perez: Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy: AstraZeneca. All other authors have declared no conflicts of interest.
Resources from the same session
4822 - Efficiacy of different nutritional intervention on nutritional status and quality of life for local advanced nasopharyngeal carcinoma patients: a prospective clinical trial
Presenter: Yuan-yuan Chen
Session: Poster Display session 3
Resources:
Abstract
2628 - Apatinib in treating patients with platinum-resistant or platinum-refractory recurrent or metastatic nasopharyngeal carcinoma
Presenter: Changjuan Tao
Session: Poster Display session 3
Resources:
Abstract
4887 - Impact of tumor site and adjuvant radiotherapy on survival of adenoid cystic carcinoma: a SEER database analysis
Presenter: Jason Tasoulas
Session: Poster Display session 3
Resources:
Abstract
2634 - Efficacy and safety of anlotinib for patients with recurrent and/or metastatic salivary gland carcinomas
Presenter: Wen Jiang
Session: Poster Display session 3
Resources:
Abstract
3568 - ACCURACY a phase (P) 2 trial of AL101, a pan-Notch inhibitor, in recurrent/metastatic (R/M) adenoid cystic carcinoma (ACC) patients (pts) with Notch activating mutations (Notch act mut): preliminary safety and efficacy data.
Presenter: Renata Ferrarotto
Session: Poster Display session 3
Resources:
Abstract
683 - Pathologic Staging Changes in Oral Cavity Squamous Cell Carcinoma—Stage Migration and Implications for Adjuvant Treatment
Presenter: Zain Husain
Session: Poster Display session 3
Resources:
Abstract
563 - Expression of immune response biomarkers in head and neck squamous cell carcinoma (HNSCC) in irradiated area
Presenter: Carole Pflumio
Session: Poster Display session 3
Resources:
Abstract
4030 - HLA-Ligandome analysis reveals target antigens of oropharyngeal squamous cell carcinoma
Presenter: Simon Laban
Session: Poster Display session 3
Resources:
Abstract
2979 - Topographical distribution of sentinel lymph nodes in early tongue squamous cell carcinomas
Presenter: Hiroyuki Goda
Session: Poster Display session 3
Resources:
Abstract
3517 - Role of follow-up (FU) FDG-PET/CT (FU-FDG-PET/CT) in patients with locoregionally advanced squamous cell carcinoma of the head and neck (LA-HNSCC) treated with chemotherapy and radiotherapy (RT), either concurrent (CRT) or sequential (ST).
Presenter: Bert Van Den Heuvel
Session: Poster Display session 3
Resources:
Abstract