Associations between detectable circulating tumor DNA and tumor glucose uptake measured by 18F-FDG PET/CT in early-stage non-small cell lung cancer

BACKGROUND

The low level of circulating tumor DNA (ctDNA) in the blood is a well-known challenge for the application of liquid biopsies in early-stage non-small cell lung cancer (NSCLC) management. Studies of metastatic NSCLC indicate that ctDNA levels are associated with tumor metabolic activity as measured by ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET/CT). This study investigated this association in NSCLC patients considered for potentially curative treatment and explored whether the two methods provide independent prognostic information.

METHOD

Patients with stage I-III NSCLC who had routinely undergone an ¹⁸F-FDG PET/CT scan and exploratory ctDNA analyses were included. Tumor glucose uptake was measured by maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) from the ¹⁸F-FDG PET/CT scans. ctDNA detectability and quantity, using variant allele frequency, were estimated by tumor-informed ctDNA analyses.

RESULTS

In total, 63 patients (median age 70 years, 60% women, and 90% adenocarcinoma) were included. The tumor glucose uptake (SUVmax, MTV, and TLG) was significantly higher in patients with detectable ctDNA (n = 19, p < 0.001). The ctDNA quantity correlated with MTV (Spearman's ρ = 0.53, p = 0.021) and TLG (Spearman's ρ = 0.56, p = 0.013) but not with SUVmax (Spearman's ρ = 0.034, p = 0.15). ctDNA detection was associated with shorter OS independent of MTV (HR: 2.70, 95% CI: 1.07-6.82, p = 0.035) and TLG (HR: 2.63, 95% CI: 1.06-6.51, p = 0.036). Patients with high tumor glucose uptake and detectable ctDNA had shorter overall survival and progression-free survival than those without detectable ctDNA, though these associations were not statistically significant (p > 0.05).

CONCLUSION

There was a positive correlation between plasma ctDNA quantity and MTV and TLG in early-stage NSCLC patients. Despite the correlation, the results indicated that ctDNA detection was a negative prognostic factor independent of MTV and TLG.

Atezolizumab and stereotactic body radiotherapy in patients with advanced non-small cell lung cancer: safety, clinical activity and ctDNA responses-the ComIT-1 trial

The introduction of immune checkpoint inhibitors has transformed the treatment landscape of metastatic non-small cell lung cancer. However, challenges remain to increase the fraction of patients achieving durable clinical responses to these drugs and to help monitor the treatment effect. In this phase II trial, we investigated the toxicity, systemic responses and circulating tumour DNA responses in patients (n = 21) with advanced non-small-cell lung cancer treated with atezolizumab and stereotactic body radiotherapy in the second or later line. We found the combined treatment to be safe with grade 3 toxicity reported in three patients. As the best overall response, four patients had a partial response, eight had stable disease and five had progressive disease. Median overall survival time was still not reached after a median follow-up of 26.5 months and 10/15 patients with programmed death-ligand 1 negative tumours were alive >18 months after the start of the study treatment. ctDNA was detectable at baseline in 11 patients. A rapid decline in ctDNA to <30% of baseline levels was seen in three patients, two of which were radiographic responders and one was considered clinically benefiting from therapy for almost 1 year.

Treatment Outcomes of Older Participants in a Randomized Trial Comparing Two Schedules of Twice-Daily Thoracic Radiotherapy in Limited-Stage SCLC

INTRODUCTION

Half of the patients with limited-stage SCLC (LS SCLC) are above or equal to 70 years old, but they account for less than 20% of participants in most trials. Comorbidities and reduced organ and physical function might lead to more treatment toxicity, and population-based studies indicate that fewer older than younger patients with LS SCLC receive standard chemoradiotherapy, although there is limited evidence for such a policy.

METHODS

We compared baseline characteristics, comorbidity, survival, treatment completion, toxicity, health-related quality of life, and treatment outcomes between patients above or equal to 70 years old and those younger than 70 years old in an open-label, randomized phase II trial comparing twice-daily thoracic radiotherapy of 45 Gy in 30 fractions with 60 Gy in 40 fractions in LS SCLC. All patients received concurrent i.v. cisplatin (75mg/m²) or carboplatin (AUC 5-6 mg/ml x min) day 1 and i.v. etoposide (100 mg/m²) day 1-3 chemotherapy. This trial is registered at ClinicalTrials.gov (NCT02041845).

RESULTS

A total of 170 patients who were above or equal to 18 years old and had performance status of 0 to 2 were randomized. Of these, 53 patients (60 Gy: 25, 45 Gy: 28) were above or equal to 70 years old and 117 (60 Gy: 64, 45 Gy: 53) were younger. There were no differences in baseline characteristics, treatment completion rates, toxicity, or response rates across the age groups. Health-related quality of life mean scores were similar during year one, but older patients reported more decline on functional scales than younger patients during year two. Overall survival was shorter for older patients, whereas there was no difference in progression-free survival or time to progression.

CONCLUSIONS

Patients above or equal to 70 years old tolerated concurrent twice-daily chemoradiotherapy and achieved similar disease control as younger patients, indicating older patients should receive the same treatment as younger patients.

Thoracic Radiotherapy in Limited-Stage Small-Cell Lung Cancer – a Population-Based Study of Patterns of Care in Norway from 2000 until 2018

Introduction

Twice-daily (BID) thoracic radiotherapy (TRT) of 45 Gy per 30 fractions is recommended for limited-stage (LS) SCLC, but most patients are treated with once-daily (OD) schedules owing to toxicity concerns and logistic challenges. An alternative is hypofractionated OD TRT of 40 to 42 Gy per 15 fractions. A randomized trial by our group indicated that TRT of 45 Gy per 30 fractions is more effective than TRT of 42 Gy per 15 fractions, and because it was not more toxic, 45 BID replaced 42 OD as the recommended schedule in Norway. The aims of this study were to evaluate to what extent BID TRT has been implemented in Norway and whether this practice change has led to improved survival.

Methods

Data on all patients diagnosed with LS SCLC from 2000 until 2018 were collected from the Cancer Registry of Norway, containing nearly complete data on cancer diagnosis, radiotherapy, and survival.

Results

A total of 2222 patients were identified; median age was 69 years, 51.8% were women, and 87.1% had stage II to III disease. Overall, 64.6% received TRT. The use of BID TRT increased from 1.8% (2000–2004) to 83.2% (2015–2018). Median overall survival among patients receiving curative TRT improved significantly during the study period (2000–2004: 17.9 mo, 2015–2018: 25.0 mo, p = 0.0023), and patients receiving 45 BID had significantly longer median overall survival than patients receiving 42 OD (BID: 26.2 mo, OD: 19.6 mo, p = 0.0015).

Conclusions

BID TRT has replaced hypofractionated OD TRT as the standard treatment of LS SCLC in Norway which has led to a significant (p = 0.0023) and clinically relevant survival improvement.

Associations between tumor mutations in cfDNA and survival in non-small cell lung cancer

INTRODUCTION

Studies have indicated that detection of mutated KRAS or EGFR in circulating tumor DNA (ctDNA) from pre-treatment plasma samples is a negative prognostic factor for non-small cell lung cancer (NSCLC) patients. This study aims to investigate whether this is the case also for NSCLC patients with other tumor mutations.

METHODS

Tumor tissue DNA from 107 NSCLC patients was sequenced and corresponding pre-treatment plasma samples were analyzed using a limited target next-generation sequencing approach validated in this study. Patients without detected mutations in tumor samples were excluded from further analyses.

RESULTS

Mutations were detected in tumor samples from 71 patients. Median age was 68 years, 51% were female, and 88% were current/former smokers, 91% had adenocarcinoma, 4% had squamous cell carcinoma and 6% had other NSCLC. The distribution between stage I, II, III and IV was 33%, 8%, 30%, and 29%, respectively. Between one and three tumor mutation(s) were detected in ctDNA from corresponding plasma samples. Patients with detected ctDNA had shorter PFS (9.6 vs. 41.3 months, HR: 2.9, 95% CI: 1.6-5.2, p = 0.0003) and OS (13.6 vs. 115.0 months, HR: 4.0, 95% CI: 2.1-7.6, p = 0.00002) than patients without detected ctDNA. ctDNA remained a significant negative prognostic factor for OS (HR: 2.5, 95% CI: 1.1-5.7, p=0.0327), but not PFS, in the multivariable analyses adjusting for baseline patient and disease characteristics including stage of disease.

CONCLUSIONS

This study adds further evidence supporting that detectable tumor mutations in cfDNA is associated with a worse prognosis in NSCLC harboring a variety of tumor mutations.

The Prognostic Effect of KRAS Mutations in Non-Small Cell Lung Carcinoma Revisited: A Norwegian Multicentre Study

BACKGROUND

due to emerging therapeutics targeting KRAS G12C and previous reports with conflicting results regarding the prognostic impact of KRAS and KRAS G12C in non-small cell lung cancer (NSCLC), we aimed to investigate the frequency of KRAS mutations and their associations with clinical characteristics and outcome. Since mutation subtypes have different preferences for downstream pathways, we also aimed to investigate whether there were differences in outcome according to mutation preference for the Raf, PI3K/Akt, or RalGDS/Ral pathways.

METHODS

retrospectively, clinicopathological data from 1233 stage I-IV non-squamous NSCLC patients with known KRAS status were reviewed. KRAS' associations with clinical characteristics were analysed. Progression free survival (PFS) and overall survival (OS) were assessed for the following groups: KRAS wild type (wt) versus mutated, KRAS wt versus KRAS G12C versus KRAS non-G12C, among KRAS mutation subtypes and among mutation subtypes grouped according to preference for downstream pathways.

RESULTS

a total of 1117 patients were included; 38% had KRAS mutated tumours, 17% had G12C. Among KRAS mutated, G12C was the most frequent mutation in former/current smokers (45%) and G12D in never smokers (46%). There were no significant differences in survival according to KRAS status, G12C status, among KRAS mutation subtypes or mutation preference for downstream pathways.

CONCLUSION

KRAS status or KRAS mutation subtype did not have any significant influence on PFS or OS.

High-dose versus standard-dose twice-daily thoracic radiotherapy for patients with limited stage small-cell lung cancer: an open-label, randomised, phase 2 trial

BACKGROUND

Concurrent chemoradiotherapy is standard treatment for limited stage small-cell lung cancer (SCLC). Twice-daily thoracic radiotherapy of 45 Gy in 30 fractions is considered to be the most effective schedule. The aim of this study was to investigate whether high-dose, twice-daily thoracic radiotherapy of 60 Gy in 40 fractions improves survival.

METHODS

This open-label, randomised, phase 2 trial was done at 22 public hospitals in Norway, Denmark, and Sweden. Patients aged 18 years and older with treatment-naive confirmed limited stage SCLC, Eastern Cooperative Oncology Group (ECOG) performance status 0-2, and measurable disease according to the Response Evaluation Criteria in Solid Tumors version 1.1 were eligible. All participants received four courses of intravenous cisplatin 75 mg/m² or carboplatin (area under the curve 5-6 mg/mL × min, Calvert's formula) on day 1 and intravenous etoposide 100 mg/m² on days 1-3 every 3 weeks. Participants were randomly assigned (1:1) in permuted blocks (sized between 4 and 10) stratifying for ECOG performance status, disease stage, and presence of pleural effusion to receive thoracic radiotherapy of 45 Gy in 30 fractions or 60 Gy in 40 fractions to the primary lung tumour and PET-CT positive lymph node metastases starting 20-28 days after the first chemotherapy course. Patients in both groups received two fractions per day, ten fractions per week. Responders were offered prophylactic cranial irradiation of 25-30 Gy. The primary endpoint, 2-year overall survival, was assessed after all patients had been followed up for a minimum of 2 years. All randomly assigned patients were included in the efficacy analyses, patients commencing thoracic radiotherapy were included in the safety analyses. Follow-up is ongoing. This trial is registered at ClinicalTrials.gov, NCT02041845.

FINDINGS

Between July 8, 2014, and June 6, 2018, 176 patients were enrolled, 170 of whom were randomly assigned to 60 Gy (n=89) or 45 Gy (n=81). Median follow-up for the primary analysis was 49 months (IQR 38-56). At 2 years, 66 (74·2% [95% CI 63·8-82·9]) patients in the 60 Gy group were alive, compared with 39 (48·1% [36·9-59·5]) patients in the 45 Gy group (odds ratio 3·09 [95% CI 1·62-5·89]; p=0·0005). The most common grade 3-4 adverse events were neutropenia (72 [81%] of 89 patients in the 60 Gy group vs 62 [81%] of 77 patients in the 45 Gy group), neutropenic infections (24 [27%] vs 30 [39%]), thrombocytopenia (21 [24%] vs 19 [25%]), anaemia (14 [16%] vs 15 [20%]), and oesophagitis (19 [21%] vs 14 [18%]). There were 55 serious adverse events in 38 patients in the 60 Gy group and 56 serious adverse events in 44 patients in the 45 Gy group. There were three treatment-related deaths in each group (one neutropenic fever, one aortic dissection, and one pneumonitis in the 60 Gy group; one thrombocytic bleeding, one cerebral infarction, and one myocardial infarction in the 45 Gy group).

INTERPRETATION

The higher radiotherapy dose of 60 Gy resulted in a substantial survival improvement compared with 45 Gy, without increased toxicity, suggesting that twice-daily thoracic radiotherapy of 60 Gy is an alternative to existing schedules.

FUNDING

The Norwegian Cancer Society, The Liaison Committee for Education, Research and Innovation in Central Norway, the Nordic Cancer Union, and the Norwegian University of Science and Technology.

Associations between muscle measures, survival, and toxicity in patients with limited stage small cell lung cancer

BACKGROUND

Standard treatment for patients with limited stage small cell lung cancer (LS SCLC) is concurrent platinum-etoposide chemotherapy and thoracic radiotherapy (TRT). Up to 30% of patients are cured, but severe toxicity is common, and we are not able to identify those who are cured or those who experience severe toxicity before chemoradiotherapy commences. Studies of other cancer patients show that low muscle mass and muscle radiodensity are associated with inferior survival and that a high drug dose per kilogram lean body mass (LBM) is associated with more toxicity, but this has not been investigated in LS SCLC. We analysed patients from a randomized trial comparing two schedules of TRT (n = 157) to investigate the prognostic and predictive role of these muscle measures in LS SCLC.

METHODS

Patients from a trial comparing once daily hypofractionated with twice daily hyperfractionated TRT were analysed. The skeletal muscle index (SMI), skeletal muscle radiodensity (SMD), and LBM were assessed from baseline computed tomography scans at the L3 level using the SliceOMatic software.

RESULTS

Images at the L3 level were available for 122 patients (77.7%). Median age was 64 years, 18% had performance status 2, and 38% had stage III. Grade 3-4 toxicity was observed in 89%, and 5% died from treatment-related side effects. Overall, the median overall survival was 23 months, and the 5 year survival was 25%. Median LBM was 45.2 (range: 16-65) kg, the median SMI 44.8 (range: 29-77) cm² /m² , and the median SMD 39.3 (range 16-62) HU. There were no significant associations between survival and any of the muscle measures in the univariable analyses (SMI: P = 0.906, SMD: P = 0.829) or in multivariable analyses adjusting for baseline characteristics (SMI: P = 0.836, SMD: P = 0.260). A higher cisplatin dose per kilogram LBM in the first course significantly increased the risk of grade 3-4 haematological toxicity (P = 0.011) and neutropenic infections (P = 0.012).

CONCLUSIONS

Patients who received a high dose of cisplatin per kilogram LBM had more haematological toxicity and neutropenic infections than other patients. None of the muscle measures were independent prognostic factors for survival in our cohort of LS SCLC patients who underwent standard chemoradiotherapy.

Randomized phase II trial comparing the efficacy of standard-dose with high-dose twice-daily thoracic radiotherapy (TRT) in limited disease small-cell lung cancer (LD SCLC)

9007

Background: Concurrent chemoradiotherapy is the standard treatment of LD SCLC. Some patients are cured, but most relapse and better treatment is needed. 45 Gy in 30 fractions BID is the most recommended TRT-schedule. Studies suggest that a higher TRT-dose might prolong survival, but hitherto, this has not been confirmed in randomized trials. We aimed to investigate whether high-dose BID TRT of 60 Gy in 40 fractions was feasible, tolerated, and improved survival. Methods: Patients > 18 years, performance status (PS) 0-2 and confirmed LD SCLC were to receive 4 courses of platinum/etoposide and were randomized to BID TRT of 60 or 45 Gy. Responders were offered prophylactic cranial irradiation of 25-30 Gy. Primary endpoint was 2-year survival; secondary endpoints were toxicity, progression free survival (PFS), and overall survival (OS). To demonstrate a 25% improvement of 2-year survival from 53% to 66% with a one-sided α = .10 and β = .80, 75 patients were required on each arm. Results: Between 2014-2018, 176 patients were enrolled at 22 Scandinavian hospitals. 160 completed TRT per protocol and were eligible for the present analyses (60 Gy: n = 84, 45 Gy: n = 76). Median age was 65, 58% women, 90% PS 0-1. There were no significant differences in grade 3–4 esophagitis (60 Gy: 19%, 45 Gy: 18%, p = .92) or grade 3–4 pneumonitis (60 Gy: 4%, 45 Gy: 0%, p = .10). There was a trend towards more neutropenic infections on the 45 Gy arm (60 Gy: 21%, 45 Gy: 36%, p = .05). There were no significant differences in other grade 3-4 toxicity. Three patients died during the study treatment period (60 Gy: one neutropenic infection and one aortic dissection; 45 Gy: one thrombocytopenic bleeding). There were no statistically significant differences in response rates (60 Gy: 88% [95% CI 81-95], 45 Gy: 85% [95% CI 76-93], p = .52) or median PFS (60 Gy: 20 months [95% CI 11-29], 45 Gy: 14 months [95% CI 10-19], p = .31). Significantly more patients on the 60 Gy arm were alive after 2 years (60 Gy: 73% [95% CI 63-83], 45 Gy: 46% [95% CI 36-60], p = .001), and they had a significantly longer median overall survival (60 Gy: 42 months [95% CI 32-51], 45 Gy: 23 months [95% CI 17-28], HR .63 [95% CI .41-.96], p = .031). Conclusions: LD SCLC patients who received BID TRT of 60 Gy had a statistically significant and numerically substantial benefit in terms of 2-year survival (primary endpoint) and median overall survival compared with those who received BID TRT of 45 Gy. The higher TRT dose did not cause more toxicity than the standard dose. Clinical trial information: NCT02041845.

Survival in Limited Disease Small Cell Lung Cancer According to N3 Lymph Node Involvement

BACKGROUND/AIM

There are several definitions of limited disease (LD) in small cell lung cancer (SCLC), differing with respect to N3 disease accepted. We analyzed patients from a randomized trial comparing two schedules of thoracic radiotherapy (TRT) in LD SCLC to investigate whether there were survival differences between N3 subcategories (n=144).

PATIENTS AND METHODS

Patients with a baseline CT scan available were analysed. Patients received four courses of cisplatin/etoposide and TRT of 45 Gy/30 fractions (twice daily) or 42 Gy/15 fractions (once daily).

RESULTS

Median overall survival (OS) was 23.3 months in the whole cohort. N3-patients (n=37) had shorter survival than those with N0-2 (16.7 vs. 33.0 months; p<0.001). There were no significant OS-differences between the N3 subcategories, but patients with metastases to two or more N3 regions had shorter survival than other N3 patients (13.4 vs. 19.9 months; p=0.011).

CONCLUSION

There were no survival differences between the N3 subcategories, suggesting that all N3 disease should be considered as LD.

Comorbidity and outcomes of concurrent chemo- and radiotherapy in limited disease small cell lung cancer

BACKGROUND

Many patients with limited disease small cell lung cancer (LD SCLC) suffer from comorbidity. Not all patients with comorbidity are offered standard treatment, though there is little evidence for such a policy. The aim of this study was to investigate whether patients with comorbidity had inferior outcomes in a LD SCLC cohort.

MATERIAL AND METHODS

We analyzed patients from a randomized study comparing two three-week schedules of thoracic radiotherapy (TRT) plus standard chemotherapy in LD SCLC. Patients were to receive four courses of cisplatin/etoposide and TRT of 45 Gy/30 fractions (twice daily) or 42 Gy/15 fractions (once daily). Responders received prophylactic cranial irradiation (PCI). Comorbidity was assessed using the Charlson Comorbidity Index (CCI), which rates conditions with increased one-year mortality.

RESULTS

In total 157 patients were enrolled between May 2005 and January 2011. Median age was 63 years, 52% were men, 16% had performance status 2, and 72% stage III disease. Forty percent had no comorbidity; 34% had CCI-score 1; 15% CCI 2; and 11% CCI 3-5. There were no significant differences in completion rates of chemotherapy, TRT or PCI across CCI-scores; or any significant differences in the frequency of grade 3-5 toxicity (p = 0.49), treatment-related deaths (p = 0.36), response rates (p = 0.20), progression-free survival (p = 0.18) or overall survival (p = 0.09) between the CCI categories.

CONCLUSION

Patients with comorbidity completed and tolerated chemo-radiotherapy as well as other patients. There were no significant differences in response rates, progression-free survival or overall survival - suggesting that comorbidity alone is not a reason to withhold standard therapy in LD SCLC.