Impact of subsequent chemotherapy on the survival of elderly patients with extensive stage small cell lung cancer

Advanced age is not the decisive factor in chemotherapy of small cell lung cancer: a population-based study

OBJECTIVE

There is limited research on the impact of chemotherapy on the prognosis of different age group patients with small cell lung cancer (SCLC). The aim of this study was to explore the impact of chemotherapy on survival prognosis of elderly patients with SCLC.

METHODS

Based on the Surveillance, Epidemiology and End Results (SEER) database, 57,460 SCLC patients between 2004 and 2015 were identified and divided into a ≤ 80 years group (n = 50,941) and a >80 years group (n = 6,519). Confounding factors were controlled by propensity score matching (PSM) analysis. Kaplan Meier (KM) analysis was performed to determine the impact of chemotherapy on overall survival (OS) and lung-cancer specific survival (LCSS) of the patients. Other variables that could affect survival of SCLC patients were also examined by COX analysis.

RESULTS

KM analysis showed that both OS and LCSS were improved in chemotherapy group compared to those in non-chemotherapy group (log rank P < 0.001) in both age groups after PSM. Cox analysis demonstrated the survival benefit of chemotherapy in both ≤ 80 years group (OS: HR 0.435; 95% CI 0.424-0.447; LCSS: HR 0.436; 95% CI 0.424-0.448) and >80 years group (OS: HR 0.424; 95% CI 0.397-0.451; LCSS: HR 0.415; 95% CI 0.389-0.444). Additionally, the following parameters had a negative impact on survival of elderly patients: male sex, tumor location in main bronchus, increased stage, bilateral tumor, no surgery or radiation, and lower median household income.

CONCLUSIONS

Elderly patients with SCLC should be encouraged to receive chemotherapy provided their general conditions permit.

Inhibiting nonhomologous end-joining repair would promote the antitumor activity of gemcitabine in nonsmall cell lung cancer cell lines

Nonsmall cell lung cancer (NSCLC) is a major type of lung cancer. In current study, we aim to evaluate whether the combination of Ku70/80 heterodimer protein inhibitor STL127705 and gemcitabine would be more favorable approach for the treatment of NSCLC compared with monotreatment with gemcitabine. Clongenic survival assay was used to determine the survival and sensitivity to irradiation. H1299 was stained with fluorescein isothiocyanate-Annexin V, and cell apoptosis was measured by flow cytometry. H1299 cells were transfected with nonhomologous end-joining (NHEJ) repair reporter, and stable cell line was selected by puromycin. NHEJ activity was determined based on the intensity of green fluorescent protein. DNA double-strand breaks (DSBs) were determined by the fluorescence intensity of γH2AX using flow cytometry. The mRNA expressions of Ku70 and Ku80 were determined using quantitative real-time PCR. Combination of STL127705 enhanced sensitivity of NSCLC cell lines to irradiation when compared with treatment with gemcitabine alone. However, small cell lung cancer cell line was not affected. H1299 cells treated with STL127705 in combination with gemcitabine showed a significantly increased apoptosis compared with H1299 cells treated with gemcitabine alone. Moreover, STL127705 treatment dramatically reduced NHEJ activity in H1299 cells when compared with gemcitabine single treatment. Increased DSBs were consistently observed in H1299 when treated with the combination of STL127705 and gemcitabine. However, the mRNA levels of Ku70 and Ku80 were upregulated by the combination treatment. It demonstrated that STL127705 enhanced antitumor activity of gemcitabine. Mechanistically, treatment with STL127705 enhanced DNA damage via inhibiting NHEJ pathway, blocking DNA-PK, and forming Ku70/80 heterodimer, eventually leading to tumor cells apoptosis.

Veliparib in Combination with Carboplatin and Etoposide in Patients with Treatment-Naïve Extensive-Stage Small Cell Lung Cancer: A Phase 2 Randomized Study

PURPOSE

This study investigated the efficacy and safety of oral PARP inhibitor veliparib, plus carboplatin and etoposide in patients with treatment-naïve, extensive-stage small cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

Patients were randomized 1:1:1 to veliparib [240 mg twice daily (BID) for 14 days] plus chemotherapy followed by veliparib maintenance (400 mg BID; veliparib throughout), veliparib plus chemotherapy followed by placebo (veliparib combination only), or placebo plus chemotherapy followed by placebo (control). Patients received 4-6 cycles of combination therapy, then maintenance until unacceptable toxicity/progression. The primary endpoint was progression-free survival (PFS) with veliparib throughout versus control.

RESULTS

Overall (N = 181), PFS was improved with veliparib throughout versus control [hazard ratio (HR), 0.67; 80% confidence interval (CI), 0.50-0.88; P = 0.059]; median PFS was 5.8 and 5.6 months, respectively. There was a trend toward improved PFS with veliparib throughout versus control in SLFN11-positive patients (HR, 0.6; 80% CI, 0.36-0.97). Median overall survival (OS) was 10.1 versus 12.4 months in the veliparib throughout and control arms, respectively (HR, 1.43; 80% CI, 1.09-1.88). Grade 3/4 adverse events were experienced by 82%, 88%, and 68% of patients in the veliparib throughout, veliparib combination-only and control arms, most commonly hematologic.

CONCLUSIONS

Veliparib plus platinum chemotherapy followed by veliparib maintenance demonstrated improved PFS as first-line treatment for ED-SCLC with an acceptable safety profile, but there was no corresponding benefit in OS. Further investigation is warranted to define the role of biomarkers in this setting.