ABSTRACT
Purpose or Objective To evaluate the influence of Charlson comorbidity index (CCI) in survival outcomes in patients (pts) with lung cancer (LC) treated with concomitant radiochemotherapy (RCT) or radiotherapy (RT) alone with radical intention during SARS-2-COVID19 pandemic. Materials and Methods Retrospective study of 50 pts with LC treated with radical intention from November 2019 to December 2020 in University Hospital of Badajoz and University Hospital Virgen Macarena in Seville. All pts were treated with radical intention and hypofractionated scheme of radiotherapy (total dose 55 Gy in 20 fractions of 2.75 Gy/daily) to decrease the duration of thoracic radiotherapy in pandemic era. 40% of pts were treated with concomitant RCT, 38% with RT alone and 22% with chemotherapy and sequential RT. CCI was used to identify associated diseases in all pts, after the evaluation of 19 items that influence in the life expectancy of them. In general, it is considered low comorbidity ≤ 3 points in CCI and high comorbidity > 3 points. Kaplan-Meier curves have been used for the statistical analysis of overall survival (OS) and cancer specific survival (CSS) and log-rank test to compare them. Results In the study, 24 pts had ≤ 3 points in CCI (48%) and 26 pts had > 3 points (52%). Mean CCS in pts with CCI≤ 3 points was 18.5 months and in pts with CCI > 3 points was 13 months. 15-months CSS was 83.3% in pts with CCI ≤ 3 points and 40.9% in pts with CCI > 3 points without statistically significant differences (p 0.755). Mean OS in pts with CCI≤ 3 points was 16.8 months and in pts with CCI > 3 points was 11.5 months.15-months OS was 74.3% in pts with CCI ≤ 3 points and 32% in pts with CCI > 3 points (p 0.620). Toxicity in both groups was similar without differences between pts with CCI ≤ 3 points and CCI > 3 points. Only one grade 3 oesophagitis was registered in CCI ≤ 3 points group. Conclusion The Charlson comorbidity index is a system that evaluates 10 years life expectancy. According to our results and despite the short follow-up, pts with CCI ≤ 3 points have better OS and CSS than pts with CCI > 3 points. In both groups, hypofractionated radiotherapy was well-tolerated regardless the CCI. Although more studies are needed, CCI can be an important factor to evaluate in patients with lung cancer because it identifies pts with a high probability of mortality. For this reason, this score can be an useful tool to assess the most suitable treatment option, especially in patients with several comorbidities.
ABSTRACT
Purpose or Objective: Moderate hypofractionation has been more popular in the last years, however no standard dosimetric parameters has been stablished. The majority of the dose-volume-constraints (DVCs) published refer to conventional 2 Gy/ fraction. In this study, we analyse different dosimetric parameters in patients (pts) with non-small cell lung cancer (NSCLC) treated with concomitant radiochemotherapy (RCT) or radiotherapy (RT) alone with radical intention and hypofractionated scheme in pandemic era. Due to the lack of consensus on this aspect, we analyse the relationship between tolerance to treatment and dosimetric parameters to aid its use in the clinic. Materials and Methods: Retrospective and multicentric study of 49 pts with locally advanced NSCLC treated from November 2019 to December 2020. During SARS-CoV-2 pandemic, hypofractionated schedules have allowed to decrease the duration of thoracic radiotherapy. The hypofractionated scheme used was 20 fractions of 2.75 Gy/daily (total dose 55 Gy, BED10=70 Gy). 3-dimensional conformal radiation therapy (3DCRT), intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) were allowed. We report gross tumour volume (GTV), planning tumour volume (PTV) and D98% and D95% PTV. Organ-at-risk (OARs) examined included lungs- GTV (V20<35% and mean-dose<20Gy), heart (V25<10%) and oesophagus (V50<40% and mean-dose<34 Gy). To evaluate toxicity during the treatment, we use CTCAE v.5 scale. Results: Mean GTV was 85.6 cc (3.3cc-581.3cc) and mean PTV was 268.8 cc (13cc-1047.4cc). Mean D98% PTV was 53 Gy and mean D95% PTV was 53.8 Gy. Most pts had G1-G2 cardiac toxicity like pericarditis, oesophagitis and pneumonitis. Only two pts (4%) had G3 oesophagitis and G3 pneumonitis (2%). No grade 4-5 toxicity was reported. In the analysis of DVCs, lungs-GTV V20<35% and lungs-GTV mean-dose < 20 Gy were associated with more pneumonitis regardless of grade (p 0.018 and p 0.027). In terms of oesophagitis, V50<40%, was associated with more oesophagitis regardless of grade (p 0.037). Mean dose < 34 Gy in oesophagus and heart DVCs were no associated with more toxicity in our study. There were not differences between T stage (<T3 vs ≥ T3) and N stage (<N2 vs ≥ N2) and mean PTV (p 0.55 and p 0.178). There were not differences in terms of cancer-specific survival and PTV (p 0.195). Conclusion: In moderately hypofractionation, it is important to consider that dosimetric parameters cannot be the same as in standard fractionation (2 Gy/fraction). Due to changing radiotherapy technique, DVCs may need to be adjusted based on different dose distribution. According to our results, hypofractionated radiotherapy in NSCLC is well-tolerated with low rates of grade 3-4- 5 toxicity but lungs-GTV V20<35%, lungs-GTV mean-dose < 20 Gy and oesophagus V50<40% were associated with more toxicity regardless of grade. Because of that, we consider it worth investigating the relationship between dosimetric parameters and toxicity in order to reach a consensus in daily clinical practice.