Involved-field radiotherapy with concurrent chemotherapy for limited-stage small-cell lung cancer: Disease control, patterns of failure and survival

Effect of FDG PET-CT for Staging and Radiotherapy Planning - A Comparison of Cohorts From Two Randomized Trials of Thoracic Radiotherapy in Limited-Stage SCLC

Introduction

18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) is recommended for staging and defining target volume in limited-stage SCLC, though the impact on outcomes compared with CT staging and elective nodal irradiation (ENI) is not well documented. We analyzed patients receiving 45 Gy/30 fractions in two randomized trials of thoracic radiotherapy (TRT) in limited-stage SCLC (HAST and THORA trials) to evaluate whether PET-CT for staging and radiotherapy planning reduces radiotoxicity and improves survival.

Methods

Patients in HAST were staged with CT of the thorax and upper abdomen and brain magnetic resonance imaging of the brain. Patients in THORA were staged with PET-CT in addition. All patients were to receive four courses of platinum/etoposide chemotherapy and concurrent TRT starting three to four weeks after the first chemotherapy course. In HAST, target volumes included pathological lesions on CT plus ENI of lymph node stations 4-7 (bilateral). In THORA, target volumes were limited to PET-CT-positive lesions (selective nodal irradiation [SNI]).

Results

A total of 149 patients were included (PET-CT/SNI: n = 76, CT/ENI: n=73); the median age was 64 years, 56% were women, 85% had PS 0 to 1, and 81% had stage III disease. The PET-CT/SNI group experienced less grade 3-4 esophagitis (18% versus 33%, p = 0.043), less grade >=1 pneumonitis (5% versus 16%, p = 0.028), and less dysphagia after TRT (mean scores on European Organisation for Research and Treatment of Cancer 13-item lung cancer module: 45 versus 72). There was no difference in median overall survival (24 versus 25 mo, p = 0.59) or progression-free survival (11 versus 11 mo, p = 0.23).

Conclusions

Using PET-CT for staging and target volume definition of TRT reduces acute radiotoxicity but does not improve overall or progression-free survival in limited-stage SCLC.

A systematic review of survival following anti-cancer treatment for small cell lung cancer

OBJECTIVES

We conducted a systematic review and meta-analysis of survival following treatment recommended by the European Society of Medical Oncology for SCLC in order to determine a benchmark for novel therapies to be compared with.

MATERIALS AND METHODS

Randomized controlled trials and observational studies reporting overall survival following chemotherapy for SCLC were included. We calculated survival at 30 and 90-days along with 1-year, 2-year and median.

RESULTS

We identified 160 for inclusion. There were minimal 30-day deaths. Survival was 99 % (95 %CI 98.0-99.0 %, I²33.9 %, n = 77) and 90 % (95 %CI 89.0-92.0 %, I²79.5 %, n = 73) at 90 days for limited (LD-SCLC) and extensive stage (ED-SCLC) respectively. The median survival for LD-SCLC was 18.1 months (95 %CI 17.0-19.1 %, I²77.3 %, n = 110) and early thoracic radiotherapy (thoracic radiotherapy 18.4 months (95 %CI 17.3-19.5, I²78.4 %, n = 100)) vs no radiotherapy 11.7 months (95 %CI 9.1-14.3, n = 10), prophylactic cranial irradiation (PCI 19.7 months vs No PCI 13.0 months (95 %CI 18.5-21.0, I²75.7 %, n = 78 and 95 %CI 10.5-16.6, I²81.1 %, n = 15 respectively)) and better performance status (PS0-1 22.5 months vs PS0-4 15.3 months (95 %CI 18.7-26.1, I²72.4 %, n = 11 and 95 %CI 11.5-19.1 I²77.9 %, n = 13)) augmented this. For ED-SCLC the median survival was 9.6 months (95 %CI 8.9-10.3 %, I²95.2 %, n = 103) and this improved when irinotecan + cisplatin was used, however studies that used this combination were mostly conducted in Asian populations where survival was better. Survival was not improved with the addition of thoracic radiotherapy or PCI. Survival for both stages of cancer was better in modern studies and Asian cohorts. It was poorer for studies administering carboplatin + etoposide but this regimen was used in studies that had fewer patient selection criteria.

CONCLUSION

Early thoracic radiotherapy and PCI should be offered to people with LD-SCLC in accordance with guideline recommendations. The benefit of the aforementioned therapies to treat ED-SCLC and the use of chemotherapy in people with poor PS is less clear.

Antitumor effect of kurarinone and underlying mechanism in small cell lung carcinoma cells

Background

Kurarinone, a prenylated flavonone isolated from the roots of Sophora flavescens, is known to be cytotoxic against many human cancer cells but not human small cell lung carcinoma (SCLC) yet. Also, the exact molecular mechanism of kurarinone for induction cytotoxicity remains unknown.

Material and methods

We investigated the effects of kurarinone on cell proliferation, apoptosis, and migration in H1688 SCLC cells. Cell viability was determined by the MTT assay. Apoptotic indices such as cell cycle, mitochondrial membrane potential, cytochrome c release, caspase activity, and death receptors were evaluated by flow cytometry. Transwell migration and invasion assays were also included.

Results

Our results indicated that kurarinone significantly decreased H1688 cell viability and induced the accumulation of sub-G1 fractions by activating caspase-3, -9, and PARP cleavage accompanied by the elevated release of cytochrome c and mitochondrial dysfunction in H1688 cells. Additionally, kurarinone promoted Fas and TRAIL receptor-1 and -2 expression via the caspase-8/Bid pathway, suggesting that kurarinone triggered apoptosis via the mitochondria-mediated and receptor-mediated apoptotic pathways. We also observed that kurarinone repressed migration and invasion capabilities of SCLC cells by suppressing the expression of epithelial-mesenchymal transition-related proteins and matrix metalloproteinases.

Conclusion

Our findings provided evidence that kurarinone can induce apoptosis in SCLC cells via multiple mechanisms and delayed the cell migration and invasion of SCLC cells.

Determination of Risk Factors Related to Supraclavicular Recurrence for Limited-Stage Small Cell Lung Cancer (SCLC) Patients

BACKGROUND This research aimed to determine high-risk factors of supraclavicular recurrence for limited-stage small cell lung cancer (LS-SCLC) patients to discover a potential subpopulation that can benefit from prophylactic supraclavicular irradiation (PSCI). MATERIAL AND METHODS Between July 2006 and July 2011, LS-SCLC patients without supraclavicular lymph node (SCLN) involvement consecutively treated with concurrent chemo-radiation but without PSCI in the Radiotherapy Department of the Cancer Institute and Hospital of Tianjin Medical University, were retrospectively analyzed. SCLN recurrence rate, overall survival (OS), and distant metastasis-free survival (DMFS) were assessed. Binary logistic regression analysis was conducted to discover the high-risk factors related to the SCLN recurrence. The receiver operating characteristic (ROC) curves were drawn to evaluate logistic regression model prediction performance. RESULTS Eighty-eight LS-SCLC patients were analyzed in this study. During 99 months (ranging from 72 months to 124 months) for survivors, 28 (31.8%) had SCLN recurrence. There were significant differences for median DMFS and OS between LS-SCLC patients with and without SCLN recurrence. The logistic regression model revealed that lymphadenopathy at mediastinal level 2 and level 3 prior to chemotherapy were significantly associated with SCLN recurrence, which was validated by ROC. CONCLUSIONS Lymphadenopathy at mediastinal level 2 and level 3 prior to chemotherapy were the high-risk factors associated with SCLN recurrence for patients with LS-SCLC. Further work is needed to determine whether patients with these factors can benefit from PSCI.

Sites of recurrent disease and prognostic factors in SCLC patients treated with radiochemotherapy

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Most recurrences occurred within the primary tumor or initially affected lymph nodes.

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All sites of loco-regional recurrence had received 92–106% of the prescribed dose.

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No isolated nodal failure occurred, supporting the use of selective nodal irradiation.

Objectives

Concurrent radiochemotherapy (RCHT) is standard treatment in locally advanced small cell lung cancer (SCLC) patients. Due to conflicting results on elective nodal irradiation (ENI) or selective node irradiation (SNI) there is no clear evidence on optimal target volumes. Therefore, the purposes of this study were to assess the sites of recurrent disease in SCLC and to evaluate the feasibility of SNI versus ENI.

Methods

A retrospective single-institution study of 43 consecutive patients treated with RCHT was performed. After state-of-the-art staging including FDG-PET/CT, all patients underwent three-dimensional conformal radiotherapy to a total dose of 45 Gy in twice-daily fractions of 1.5 Gy starting concurrently with the first or second chemotherapy cycle. All sites of loco-regional recurrences were correlated to the initial tumor and dose delivered. The impact of potential prognostic variables on outcome was evaluated using the Cox-regression model.

Results

13 patients (30%) relapsed locally or regionally: six within the initial primary tumor volume, five within the initially affected lymph nodes, one metachronously within primary tumor and initially affected lymph nodes, and one both inside and outside of the initial nodal disease. All sites of loco-regional recurrence had received 92–106% of the prescribed dose.

Conclusion

In our study most recurrences occurred within the primary tumor or initially affected lymph nodes, or distantly. We did not register any case of isolated nodal failure, supporting the use of selective nodal irradiation, possibly with the addition of supraclavicular irradiation in patients with nodal disease in the upper mediastinum.

Evaluation of factors associated with loco-regional failure and survival in limited disease small cell lung cancer patients treated with chemoradiotherapy

BACKGROUND

Loco-regional failure (LRF) remains a significant problem in limited disease small cell lung cancer (LD-SCLC) patients treated with definitive chemoradiotherapy. Dose-escalation may be a way forward to reduce the failure rate. However, the risk of toxicity rises with increasing doses. Knowledge on factors associated with LRF could aid the selection of patients for more aggressive treatment. Therefore, the aim of this study is to evaluate factors correlated with LRF in a cohort of LD-SCLC patients treated with definitive chemoradiotherapy. Moreover, factors associated with improved survival were investigated.

MATERIAL AND METHODS

We included 147 consecutive LD-SCLC patients treated from 2007 to 2013. Radiotherapy was delivered as either 45 Gy in 1.5-Gy fractions twice daily or 46-50 Gy in 2-Gy fractions once daily. Chemotherapy was etoposide combined with either carboplatin or cisplatin given mainly concomitantly with radiotherapy. Pattern of first failure and survival were evaluated retrospectively. Cumulative LRF (CLRF) and overall survival (OS) were calculated by the Kaplan-Meier method. The impact of covariates on LRF and OS was evaluated by using Cox proportional hazards model.

RESULTS

With a median follow-up time of 42.2 months, 37 patients experienced LRF as first failure. Isolated LRF was seen in 16 patients, but no isolated regional failure was seen. The CLRF rate was 22% at 1-year and 43% at 3-years. N3-stage was an independent prognostic factor correlated with LRF development (p = 0.043). Median OS was 24.1 months (95% CI 19-29 months) and a three-year survival of 34%. Prognostic factors associated with improved OS were staging including a positron emission tomography (PET) scan (p = 0.004) and receiving prophylactic cranial irradiation (PCI) (p = 0.006).

CONCLUSION

N3-stage was an independent prognostic factor for LRF. Receiving a pretreatment PET scan and receiving PCI were prognostic factors for improved OS. Reduction in LRF may be achieved with dose-escalation in patients with N3-stage. This can be evaluated in prospective dose-escalation trials.

Timing of Failure in Limited Disease (Stage I-III) Small-Cell Lung Cancer Patients Treated with Chemoradiotherapy: A Retrospective Analysis

Aims and background

Follow-up in limited disease (stage I-III) small cell lung cancer could be further optimized by assessment of the temporal and locational distribution of treatment failure after completion of chemoradiotherapy.

Methods and study design

Follow-up was retrospectively analyzed in 125 limited disease (stage I-III) small cell lung cancer patients with initial performance status WHO <3 who had successfully completed chemoradiotherapy. Thoracic irradiation was applied in the concurrent or sequential mode. Time from initial pathological diagnosis and treatment end to local, distant and brain recurrence was documented.

Results

One- and two-year progression-free survival rates were 50% and 27.2% in patients treated with concurrent and 45.2% and 14.2% in those treated with sequential chemoradiotherapy, respectively. Local relapse was documented in 14% patients treated with concurrent and 16% with sequential chemoradiotherapy. The distant failure rate was 43% in both subgroups. Up to the end of the follow-up period, more patients treated with concurrent chemoradiotherapy had developed brain metastases than those treated sequentially (37% vs 20%, P = 0.049). Median time (in days) to local relapse was 376 and 401 from the initial diagnosis, 200 and 309 from the end of chemotherapy, and 316 and 196 from the end of thoracic irradiation; to distant failure was 275 and 298 from the initial diagnosis, 151 and 157 from the end of chemotherapy and 180 and 84 from the end of thoracic irradiation; to brain relapse was 330 and 273 from the initial diagnosis, 123 and 151 from the end of chemotherapy and 213 and 73 from the end of thoracic irradiation in patients treated with concurrent and sequential chemoradiotherapy, respectively. There was no significant difference in the temporal distribution of treatment failure in either subgroup.

Conclusions

In more than half of the patients who developed a distant recurrence, including brain metastases, treatment failure occurred in the first year after the initial diagnosis. Intensified follow-up can be recommended at least in the first year, because no sufficient eradication of the systemic small cell lung cancer with the applied chemoradiotherapy protocol could be achieved.

Locoregional failures following thoracic irradiation in patients with limited-stage small cell lung carcinoma

PURPOSE

To determine the patterns of loco-regional (LR) and distant failure in patients with limited-stage small cell lung carcinoma (LS-SCLC) treated with curative intent.

METHODS

From 1997 to 2008, 253 LS-SCLC patients were treated with curative intent chemo-radiation at our institution. A retrospective review identified sites of failure. The cumulative LR failure (LRF) rate was calculated. Distant failure-free survival (FFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Volumetric images of LR failures were delineated and registered with the original radiation treatment plans if available. Dosimetric parameters for the delineated failure volumes were calculated from the original treatment information.

RESULTS

The median follow-up was 19 months. The site of first failure was LR in 34, distant in 80 and simultaneous LR and distant in 31 patients. The cumulative LRF rate was 29% and 38% at 2 and 5 years. OS was 44% at 2 years. Seventy patients had electronically archived treatment plans of which there were 16 LR failures (7 local and 39 regional failure volumes). Of the local and regional failure volumes 29% and 31% were in-field, respectively.

CONCLUSIONS

The predominant pattern of LR failure was marginal or out-of-field. LR failures may be preventable with improved radiotherapy target definition.

[Radiotherapy of lung cancer: Any room left for elective mediastinal irradiation in 2011?]

Traditionally, the target volumes of curative-intent radiotherapy for non-small cell lung cancer include all uninvolved mediastinal nodes. However, an improvement in tumour control requires an increase of the total dose to the macroscopic target volume. This is only achievable if the irradiation of the organs at risk is reduced, i.e. elective irradiation of the mediastinum is omitted. The available data suggest that elective mediastinal irradiation may be safely omitted, provided that an adequate staging procedure, including FDG PET-CT, has been performed.