Hyperfractionated Accelerated Radiotherapy Versus Stereotactic Body Radiotherapy in the Treatment of Limited-Stage Small Cell Lung Cancer: A Matched-Pair Analysis

BACKGROUND

Concurrent chemoradiotherapy based on hyperfractionated accelerated radiotherapy (HART) is the first-line recommended regimen for the treatment of small-cell lung cancer (SCLC). However, Stereotactic Body Radiotherapy (SBRT) is also regarded as an effective treatment for limited-stage (LS) SCLC, and the efficacy and safety of HART versus SBRT stay controversial.

METHODS

In this study, 188 LS-SCLC patients were retrospectively divided into two groups receiving chemotherapy combined with either HART or SBRT. In HART group, patients received 4500 cGy in 30 fractions, administered twice daily for 3 weeks. Whereas in the SBRT group, a total radiation dose of 4000-4500 cGy was delivered in 10 fractions over 2 weeks. Thirty-three pairs of patients were finally included for next analysis.

RESULTS

The estimated objective response rates were 63.6 % (21/33) and 78.8 % (26/33) in HART group and SBRT group, respectively (P = 0.269). Furthermore, there was no significant difference between HART and SBRT groups in overall survival (26 months vs. 29 months, P = 0.362) and progression free survival (11 months vs. 15 months, P = 0.223). As for the adverse events, toxicity of both groups is similar and slight that no grade 4 event was observed. Grade 3 pneumonitis cases were all occurred in the HART group (9.1%, 3/33, P = 0.238), and grade 3 esophagitis cases were all occurred in the SBRT group (6.1%, 2/33, P = 0.492).

CONCLUSION

Compared with HART, SBRT could be another effective treatment with satisfactory safety for the concurrent chemoradiotherapy in patients with LS-SCLC.

A retrospective real-world experience of immunotherapy in patients with extensive stage small-cell lung cancer

BACKGROUND

The treatment of extensive stage small-cell lung cancer (ES-SCLC) has only made modest progress in the past decade, with two immune checkpoint inhibitors (ICIs), atezolizumab and durvalumab, approved for the treatment of SCLC by January 2022. However, currently, there is limited real-world data on ES-SCLC patients received immunotherapy.

METHODS

We retrospectively collected and analyzed the demographic and treatment data of ES-SCLC patients at the First Affiliated Hospital of Guangzhou Medical University from January 2017 to January 2022. Survival and prognosis information was obtained through follow-up.

RESULTS

A total of 353 ES-SCLC patients were included, of which 165 received immunotherapy combined with chemotherapy as the first-line (FL) treatment (chemo-immune group), and 188 received chemotherapy (chemotherapy group). The objective response rate (ORR) and disease control rate (DCR) of patients receiving immunotherapy as the FL treatment were better than the chemotherapy group (76.97% vs. 48.40%, p < 0.001, and 83.03% vs. 68.09%, p < 0.001). Moreover, the progression-free survival (PFS) and overall survival (OS) of ES-SCLC patients receiving immunotherapy as the FL treatment were better than the chemotherapy group (6.7 months vs. 5.1 months, p < 0.001, and 12.5 months vs. 11.2 months, p < 0.001). Furthermore, the OS of ES-SCLC patients who received immunotherapy as second-line treatment was better than that in the chemotherapy group (15.9 months vs. 12.9 months, p = 0.036).

CONCLUSION

ICIs combined with chemotherapy as the FL treatment could be beneficial to the ORR, DCR, PFS, and OS of ES-SCLC patients. Furthermore, ES-SCLC patients can benefit from ICIs in the second-line treatment, even if they had not received ICIs in the FL treatment.

Differentiation of brain metastases from small and non-small lung cancers using apparent diffusion coefficient (ADC) maps

BACKGROUND

Brain metastases are particularly common in patients with small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC showing a less  aggressive clinical course and lower chemo- and radio sensitivity compared to SCLC. Early adequate therapy is highly desirable and depends on a reliable classification of tumor type. The apparent diffusion coefficient is a noninvasive neuroimaging marker with the potential to differentiate between major histological subtypes. Here we determine the sensitivity and specificity of the apparent diffusion coefficient to distinguish between NSCLC and SCLC.

METHODS

We enrolled all NSCLC and SCLC patients diagnosed between 2008 and 2019 at the University Medical Center Göttingen. Cranial MR scans were visually inspected for brain metastases and the ratio of the apparent diffusion coefficient (ADC) was calculated by dividing the ADC measured within the solid part of a metastasis by a reference ADC extracted from an equivalent region in unaffected tissue on the contralateral hemisphere.

RESULTS

Out of 411 enrolled patients, we detected 129 patients (83 NSCLC, 46 SCLC) with sufficiently large brain metastases with histologically classified lung cancer and no hemorrhage. We analyzed 185 brain metastases, 84 of SCLC and 101 of NSCLC. SCLC brain metastases showed an ADC ratio of 0.68 ± 0.12 SD, and NSCLC brain metastases showed an ADC ratio of 1.47 ± 0.31 SD. Receiver operating curve statistics differentiated brain metastases of NSCLC from SCLC with an area under the curve of 0.99 and a 95% CI of 0.98 to 1, p < 0.001. Youden's J cut-point is 0.97 at a sensitivity of 0.989 and a specificity of 0.988.

CONCLUSIONS

In patients with lung cancer and brain metastases with solid tumor parts, ADC ratio enables an ad hoc differentiation of SCLC and NSCLC, easily achieved during routine neuroradiological examination. Non-invasive MR imaging enables an early-individualized management of brain metastases from lung cancer.

TRIAL REGISTRATION

The study was registered in the German Clinical Trials Register (DRKS00023016).

REPLATINUM Phase III randomized study: RRx-001 + platinum doublet versus platinum doublet in third-line small cell lung cancer

RRx-001 is a cysteine-directed anticancer alkylating agent with activity in a Phase II study in platinum refractory small cell lung cancer. Here, we describe the design of REPLATINUM, an open-label, Phase III trial. 120 patients with previously platinum-treated small cell lung cancer in third line will be randomized 1:1 to receive RRx-001 followed by four cycles of a platinum doublet, and then alternating cycles of RRx-001 and single agent platinum until progression versus four cycles of a platinum doublet. At radiologic progression on the platinum doublet, patients may cross over to the RRx-001 arm. Primary objective: to demonstrate superior progression-free survival in the RRx-001 population. Secondary objectives: to demonstrate superiority for overall survival and objective response rate. Clinical Trial registration: NCT03699956.

Impact of thoracic radiation therapy after chemotherapy on survival in extensive-stage small cell lung cancer: A propensity score-matched analysis

Background

The role of thoracic radiation therapy (TRT) after chemotherapy (CHT) in extensive‐stage small cell lung cancer (ES‐SCLC) has not been well defined. We investigated whether intensity‐modulated radiotherapy (IMRT) improves outcomes in ES‐SCLC after CHT compared to CHT alone.

Methods

A total of 292 patients who reached a complete response (CR), partial response (PR), or stable disease (SD) after CHT were assigned into groups: CHT + TRT and CHT alone. Propensity score matching was used to balance patient groups (n = 72 each).

Results

The five‐year overall survival (OS: 12.3% vs. 3.6%; P < 0.001) and progression‐free survival (PFS: 3.2% vs. 1.7%; P = 0.006) rates were significantly higher in the CHT + TRT group. This data was confirmed in the matched samples (5‐year OS: 10.5% vs. 1.6%, P < 0.001; PFS: 4.3% vs. 0.0%, P = 0.023). The overall (P = 0.002) and locoregional (P < 0.001) recurrence rates in the CHT + TRT group were significantly lower than in the CHT group. Univariate analysis showed that response evaluation after CHT and TRT were significant prognostic factors of OS. Multivariate analyses revealed that N Stage 0–1 (P = 0.02), > 6 cycles of CHT (P = 0.042), CR + PR after CHT (P < 0.001), and TRT (P < 0.001) were independently associated with longer OS compared to CHT alone.

Conclusion

TRT using IMRT is strongly correlated with improved OS and PFS in ES‐SCLC patients reaching CR, PR or SD after CHT. A multicenter, randomized phase III clinical trial is needed to confirm these findings.

The role of radiation therapy in the management of small cell lung cancer

Small cell lung cancer (SCLC) is a very aggressive form of lung cancer. SCLC treatment requires multidisciplinary management and timely treatment. Radiation therapy is an important part of management of all stages of SCLC, in the curative as well as in the palliative setting. The role of radiation therapy in all stages of SCLC has changed in recent years; this article describes these changes and highlights the role of radiation therapy in the management of SCLC.

What's New in SCLC? A Review

A few years ago the answer to the question in the title of this review would have been, "unfortunately not much" or even "nothing", likely eliciting knowing nods of agreement from oncologists. For the last 3 decades, SCLC has been notorious for its lack of progress, as drug after drug, over 60 of them, in fact, including inhibitors of VEGF, IGFR, mTOR, EGFR and HGF has failed and fallen by the wayside due to little or no impact on PFS or OS, while SCLC's cousin, NSCLC, has notched success after success with a spate of targeted treatment and immunotherapy regulatory approvals. However, a paradigm shift or, more appropriately, a 'paradigm nudge' is quietly underway in extensive stage SCLC with a series of agents that in early clinical trials have shown the potential to 'lift the curse' in SCLC, heretofore referred to as "a graveyard for drug development". These agents, constituting the "best of what's new" in SCLC, and discussed in this review following a brief overview of the classification, epidemiology, prognosis and current treatment of SCLC, include checkpoint inhibitors, antibody-drug conjugates, PARP inhibitors, epigenetic inhibitor/innate immune activator, and an inhibitor of RNA polymerase II. Compared to NSCLC, the therapeutic options are still limited but with one or more successes to build momentum and drive long-overdue R&D and clinical investment the hope is that the approval floodgates may finally open.

Timing of thoracic radiotherapy in the treatment of extensive-stage small-cell lung cancer: important or not?

Background

This study evaluated the prognosis of patients with extensive-stage small-cell lung cancer (ES-SCLC) that may be associated with timing of thoracic radiotherapy (TRT).

Methods

ES-SCLC patients (n = 232) without progression were retrospectively analyzed after first-line induction chemotherapy. Patients in the TRT group were stratified as early-TRT (ERT; ≤3 cycles of induction chemotherapy received prior to TRT, n = 65) or late-TRT (LRT; >3 cycles, n = 122). To avoid selection bias, we conducted Propensity Score Matching (PSM) for patients. Overall survival (OS), progression-free survival (PFS), and locoregional recurrence-free survival (LRRFS) were assessed and compared.

Results

Overall, the median survival time, PFS, and LRRFS were 13.2, 8.7, and 14.6 months, respectively. After matching by PSM, there were 45 patients total in the TRT/non-TRT groups, and 56 patients total in the ERT/LRT groups. OS, PFS, and LRRFS were significantly longer in the TRT group than the non-TRT group (P < 0.001, all). However, between the ERT and LRT groups these survival parameters were similar (P > 0.05, all).

Conclusion

For ES-SCLC patients without progression, the addition of TRT after first-line chemotherapy benefited survival greatly. Early TRT showed no significant benefit over late TRT.

Thoracic radiation therapy could give survival benefit to elderly patients with extensive-stage small-cell lung cancer

AIM

To evaluate the effect of thoracic radiation therapy (TRT) in elderly patients (aged ≥65 years) with extensive-stage small-cell lung cancer (ES-SCLC).

PATIENTS & METHODS

This study reviewed the records of 118 elderly patients with ES-SCLC (all with distant metastasis) through January 2006-December 2013. The patients were divided into either a chemotherapy (ChT)/TRT-combination group or a ChT-alone group.

RESULTS

The median survival time and 3-year overall survival rates in the ChT/TRT group were significantly higher than those in the ChT-alone group (17.0 vs 11.7 months; 18.1 vs 14.9%; p = 0.014). The 3-year overall survival rates in patients who received prophylactic cranial irradiation were also higher than the rates in patients who did not receive prophylactic cranial irradiation (18.1 vs 5.1%; p = 0.708).

CONCLUSION

TRT combined with ChT could provide a survival benefit to elderly patients with ES-SCLC.

Paclitaxel plus bevacizumab in patients with chemoresistant relapsed small cell lung cancer as salvage treatment: a phase II multicenter study of the Hellenic Oncology Research Group

INTRODUCTION

Therapeutic options for patients with relapsed, chemo-resistant small-cell lung cancer (SCLC) are limited. Since paclitaxel has demonstrated single-agent activity in the second-line setting of SCLC and angiogenesis seems to play an important role in the pathogenesis of the disease, a phase II trial was conducted in order to evaluate the efficacy and the tolerance of their combination in patients with relapsed, chemo-resistant SCLC.

PATIENTS AND METHODS

Patients with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 who experienced relapse within 3 months after completion of 1st line chemotherapy for SCLC were eligible. Patients were treated with paclitaxel (90 mg/m(2), days 1, 8 and 15) along with bevacizumab (10mg per kg of body weight, days 1 and 15) in cycles of 28 days.

RESULTS

Thirty patients (male/female: 27/3) with a median age of 64 years and ECOG performance status 0/1/2: 2/25/3 were enrolled. Nineteen patients (63.3%) had received at least two lines of prior treatment, 17 (56.7%) had undergone prior radiotherapy and nine (30%) had brain metastases at the time of study entry. The overall objective response rate was 20% (95% CI: 5.69-34.31%), including one complete remission, whereas the disease control rate was 36.7%. The median duration of response was 2.5 months (range, 1.5-5.7), the median progression-free survival 2.7 months (range, 0.5-9.2) and the median overall survival 6.3 months (range, 0.5-17.9). Grades 3 and 4 toxicities were limited in neutropenia, diarrhea and fatigue. There was one case of non-fatal pulmonary embolism.

CONCLUSIONS

The combination of paclitaxel with bevacizumab was feasible and active in this poor prognosis and heavily pretreated population of patients with advanced, chemoresistant SCLC, representing a valid therapeutic alternative which merits further evaluation.

Biomarker analysis in a phase III study of pemetrexed-carboplatin versus etoposide-carboplatin in chemonaive patients with extensive-stage small-cell lung cancer

BACKGROUND

Clinical results of a randomized phase III trial comparing pemetrexed-carboplatin (PC) with etoposide-carboplatin (EC) in chemonaive patients with extensive-stage disease small-cell lung cancer (ED-SCLC) resulted in trial closure for futility; biomarker analyses using immunohistochemistry (IHC) and single-nucleotide polymorphisms (SNPs) are described herein.

PATIENTS AND METHODS

Thymidylate synthase (TS), excision repair cross complementing-1 (ERCC1), glycinamide ribonucleotide formyltransferase (GARFT), and folylpolyglutamate synthetase (FPGS) were investigated using IHC (n=395). SNPs were genotyped for TS, FPGS, γ-glutamyl hydrolase (GGH), methylenetetrahydrofolate reductase (MTHFR), folate receptor-α FR-α, and solute carrier 19A1 (SLC19A1; n=611).

RESULTS

None of the IHC biomarkers (folate pathway or ERCC1) were found to be predictive or prognostic in this setting. rs2838952 (adjacent to SLC19A1) had significant treatment-independent association with overall survival (OS; hazard ratio 0.590, P=0.01). Nine GGH-associated SNPs interacted with rs3788205 (SLC19A1) for OS on the PC arm. rs12379987 (FPGS) interacted with treatment for OS (interaction P=0.036).

CONCLUSION

Potential ERCC1 and folate pathway IHC biomarkers failed to predict outcome in either study arm in ED-SCLC. SNPs in regions including FPGS and SLC19A1 and interacting SNPs in GGH and SLC19A1 were associated with differences in OS; however, none of these SNPs predicted for greater survival with PC over EC.

Thoracic radiation therapy improves the overall survival of patients with extensive-stage small cell lung cancer with distant metastasis

BACKGROUND

The authors conducted a retrospective study to evaluate the effects of thoracic radiation therapy (TRT) for patients with extensive-stage small cell lung cancer (ED-SCLC).

METHODS

Between January 2003 and December 2006, the records of 119 patients who were diagnosed with ED-SCLC (all with distant metastasis [M1]) were included in the study. Sixty patients received chemotherapy (ChT) and TRT (ChT/TRT), and 59 patients received ChT alone. The ChT regimens consisted of either carboplatin and etoposide (CE) or cisplatin and etoposide (PE). The total dose of TRT ranged from 40 to 60 grays (Gy) at 1.8 to 2.0 Gy per fraction.

RESULTS

For the entire group, the median survival was 13 months, and the 2-year and 5-year overall survival (OS) rates were 26.1% and 6.5%, respectively. The median survival and the 2-year and 5-year OS rates were 17 months, 35%, and 7.1%, respectively, in the ChT/TRT group and 9.3 months, 17%, and 5.1%, respectively, in the ChT group (P = .014). However, this improvement was achieved at the expense of low toxicity. Multivariate analysis revealed that receiving ≥4 cycles of ChT (P = .032) and TRT (P = .005) were favorable prognostic factors for OS. Of all toxicities, only high-grade leucopenia (grade >3) was more frequent in the ChT/TRT group.

CONCLUSIONS

The addition of TRT to ChT improved the OS of patients with ED-SCLC. Furthermore, receiving ≥4 cycles of ChT and TRT were independent, favorable prognostic factors for OS.

Identification of thymidylate synthase as a potential therapeutic target for lung cancer

Background:

Thymidylate synthase (TS), a key enzyme in the de novo synthesis of thymidine, is an important chemotherapeutic target for malignant tumours including lung cancer. Although inhibition of TS has an antiproliferative effect in cancer cells, the precise mechanism of this effect has remained unclear.

Methods:

We examined the effects of TS inhibition with an RNA interference-based approach. The effect of TS depletion on the growth of lung cancer cells was examined using colorimetric assay and flow cytometry.

Results:

Measurement of the enzymatic activity of TS in 30 human lung cancer cell lines revealed that such activity differs among tumour histotypes. Almost complete elimination of TS activity by RNA interference resulted in inhibition of cell proliferation in all tested cell lines, suggestive of a pivotal role for TS in cell proliferation independent of the original level of enzyme activity. The antiproliferative effect of TS depletion was accompanied by arrest of cells in S phase of the cell cycle and the induction of caspase-dependent apoptosis as well as by changes in the expression levels of cyclin E and c-Myc. Moreover, TS depletion induced downregulation of the antiapoptotic protein X-linked inhibitor of apoptosis (XIAP), and it seemed to activate the mitochondrial pathway of apoptosis.

Conclusion:

Our data provide insight into the biological relevance of TS as well as a basis for clinical development of TS-targeted therapy for lung cancer.

Small cell lung cancer: are we making progress?

Although the incidence of small cell lung cancer (SCLC) has declined during the past 30 years, it remains a significant cause of cancer mortality in the United States and across the world. With appropriate treatment, about 20% of patients who present with limited stage SCLC can be cured of their disease. Unfortunately, the outcome for the remainder of patients is extremely poor. The only significant advance in extensive stage SCLC in the past 2 decades is the recent discovery that prophylactic cranial irradiation improves survival in those patients whose disease has responded to initial chemotherapy. Numerous attempts to enhance the antitumor effects of traditional chemotherapy for SCLC have not been successful. As the understanding of the biology of SCLC increased, a number of rational molecular targets for therapy have been identified. Although initial attempts at "targeted therapy" in SCLC have been unsuccessful, several newly identified targets hold promise and give hope that significant improvements in therapy for this challenging disease are not far away.