Does routine clinical practice reproduce the outcome of large prospective trials? The analysis of institutional database on patients with limited-disease small-cell lung cancer

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.

Thoracic irradiation in 3weeks for limited-stage small cell lung cancer: Is twice a day fractionation really needed?

PURPOSE

Many Canadian institutions treat limited-disease small cell lung cancer with 40Gy in 15 fractions delivered once-a-day in 3weeks concomitantly with chemotherapy. This regimen is convenient and seems to be effective. Here, we report and compare with a literature review the outcomes of patients with limited-stage small cell lung cancer treated in our institution with this hypofractionated regimen.

PATIENTS AND METHODS

From January 2004 to December 2012, patients with limited-stage small cell lung cancer treated curatively with platinum-based chemotherapy and concurrent thoracic radiotherapy at a dose of 40Gy in 16 fractions once-a-day were eligible for this review.

RESULTS

Sixty-eight patients fit the analysis criteria, including ten patients with small pleural effusion. The median age was 66years old. After a median follow-up of 77months for those alive, the median survival was 28months. At 3 and 5years respectively, the locoregional control rates were 67 and 64%, while the overall survival rates were 40 and 35%. Prophylaxis cranial irradiation was delivered to 68% of the patients. Grade 2 and 3 acute esophagitis occurred in respectively 49 and 9% of the patients. There was no grade 4 radiation-induced toxicity. All patients, except for one, completed their thoracic irradiation course without interruption.

CONCLUSION

Once-a-day hypofractionated radiation with concurrent chemotherapy followed by prophylactic cranial irradiation is a practical regimen. Based on our experience and the published literature, it appears to be similarly effective as regimens using twice-daily fractionation in 3weeks, or once-daily in 6 to 7weeks with higher radiotherapy doses. Further prospective comparisons of hypofractionation with the current recommendations are needed.

Randomized phase II trial comparing twice daily hyperfractionated with once daily hypofractionated thoracic radiotherapy in limited disease small cell lung cancer

BACKGROUND

Concurrent chemotherapy and thoracic radiotherapy (TRT) is recommended for limited disease small cell lung cancer (LD SCLC). Twice daily TRT is well documented, but not universally implemented - probably mainly due to inconvenience and concerns about toxicity. A schedule of three-week hypofractionated TRT is a commonly used alternative. This is the first randomized trial comparing twice daily and hypofractionated TRT in LD SCLC.

MATERIAL AND METHODS

Patients received four courses of cisplatin/etoposide (PE) and were randomized to TRT of 42 Gy in 15 fractions (once daily, OD) or 45 Gy in 30 fractions (twice daily, BID) between the second and third PE course. Good responders received prophylactic cranial irradiation of 30 Gy in 15 fractions.

RESULTS

157 patients were enrolled between May 2005 and January 2011 (OD: n = 84, BID: n = 73). Median age was 63 years, 52% were men, 84% had performance status 0-1, 72% had stage III disease and 11% non-malignant pleural effusion. The treatment arms were well balanced. The response rates were similar (OD: 92%, BID: 88%; p = 0.41), but more BID patients achieved a complete response (OD: 13%, BID: 33%; p = 0.003). There was no difference in one-year progression-free survival (PFS) (OD: 45%, BID: 49%; p = 0.61) or median PFS (OD: 10.2 months, BID: 11.4 months; p = 0.93). The median overall survival in the BID arm was 6.3 months longer (OD: 18.8 months, BID: 25.1 months; p = 0.61). There were no differences in grade 3-4 esophagitis (OD: 31%, BID: 33%, p = 0.80) or pneumonitis (OD: 2%, BID: 3%, p = 1.0). Patients on the BID arm reported slightly more dysphagia at the end of the TRT.

CONCLUSION

There was no difference in severe toxicity between the two TRT schedules. The twice daily schedule resulted in significantly more complete responses and a numerically longer median overall survival, but no firm conclusions about efficacy could be drawn from this phase II trial.

Management of brain metastasis with magnetic resonance imaging and stereotactic irradiation attenuated benefits of prophylactic cranial irradiation in patients with limited-stage small cell lung cancer

Background

Magnetic resonance imaging (MRI) enables a more sensitive detection of brain metastasis and stereotactic irradiation (SRI) efficiently controls brain metastasis. In limited-stage small cell lung cancer (LS-SCLC), prophylactic cranial irradiation (PCI) in patients with good responses to initial treatment is recommended based on the survival benefit shown in previous clinical trials. However, none of these trials evaluated PCI effects using the management of brain metastasis with MRI or SRI. This study aimed to determine the effects of MRI and SRI on the benefits of PCI in patients with LS-SCLC.

Methods

The clinical records of pathologically proven SCLC from January 2006 to June 2013 in facilities equipped with or had access to SRI in Japan were retrospectively reviewed. Patients with LS-SCLC and complete or good partial responses after initial treatment were included in the study and analyzed by the Kaplan-Meier method.

Results

Of 418 patients with SCLC, 124 met criteria and were divided into patients receiving PCI (PCI group; n = 29) and those without PCI (non-PCI groups; n = 95). At baseline, ratios of patients with stage III were significantly advantageous for the non-PCI group, although younger age and high ratios of complete response and MRI confirmed absence of brain metastasis were advantageous for the PCI group. Neither median survival times (25 vs. 34 months; p = 0.256) nor cumulative incidence of brain metastasis during 2 years (45.5 vs. 30.8 %; p = 0.313) significantly differed between the two groups. Moreover, these factors did not significantly differ among patients with stage III disease (25 vs. 26 months; p = 0.680, 42.3 vs. 52.3 %; p = 0.458, respectively).

Conclusion

PCI may be less beneficial in patients with LS-SCLC if the management with MRI and SRI is available.

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.