Safety and effectiveness of stereotactic body radiotherapy for a clinically diagnosed primary stage I lung cancer without pathological confirmation

Comparison of long-term outcomes of stereotactic body radiotherapy (SBRT) via Helical tomotherapy for early-stage lung cancer with or without pathological proof

BACKGROUND

Stereotactic body radio therapy (SBRT) has emerged as a standard treatment option for nonsurgical candidates with early-stage non-small cell lung cancer (NSCLC). Pathological proof is sometimes difficult to obtain in patients with solitary pulmonary nodules (SPNs). We aimed to compare the clinical outcomes of stereotactic body radiotherapy via helical tomotherapy (HT-SBRT) for early-stage lung cancer patients with or without a pathological diagnosis.

METHODS

Between June 2011 and December 2016, we treated 119 lung cancer patients with HT-SBRT, including 55 with a clinical diagnosis and 64 with a pathological diagnosis. Survival outcomes, including local control (LC), progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS), were compared between two cohorts with and without a pathological diagnosis.

RESULTS

The median follow-up for the whole group was 69 months. Patients with a clinical diagnosis were significantly older (p = 0.002). No significant differences were observed between the clinical and pathological diagnosis cohorts in terms of the long-term outcome, with 5-year LC, PFS, CSS, and OS of 87% versus 83% (p = 0.58), 48% versus 45% (p = 0.82), 87% versus 84% (p = 0.65), and 60% versus 63% (p = 0.79), respectively. Recurrence patterns and toxicity were also similar.

CONCLUSIONS

Empiric SBRT appears to be a safe and effective treatment option in a multidisciplinary setting when patients with SPNs highly suggestive of malignancy are unable/refuse to obtain a definitive pathological diagnosis.

Stereotactic body radiation therapy for empirically treated hypermetabolic lung lesions: a single-institutional experience identifying the Charlson score as a key prognostic factor

Background

Though pathologic evidence for non-small cell lung cancer (NSCLC) is preferred, many patients do not receive a biopsy prior to treatment with stereotactic body radiation therapy (SBRT). This study seeks to analyze the overall survival (OS), local control, and toxicity rates for such patients.

Methods

This retrospective review included patients empirically treated with SBRT for presumed non-metastatic NSCLC at a single institution. Inclusion criteria included a hypermetabolic pulmonary lesion noted on positron emission tomography (PET) imaging but no pathological evidence of NSCLC. Patients with another known metastatic tumor were excluded. Statistical analysis was conducted with Cox proportional hazards analysis, univariate analysis, and the Kaplan-Meier method.

Results

Ninety-one treatments in 90 unique patients met inclusion criteria. Patients were a median 77.9 years at the start of treatment and had a median Charlson score of 7. Pre-treatment standardized uptake value (SUV) was a median 4.5 and 1.5 after treatment. At a median follow-up of 12.9 months, 36-month local control of 91.3% was achieved. Twenty-four-month OS and progression-free survival were 65.4% and 44.8%, respectively. On univariate analysis, biologically effective dose (BED) ≥120 Gy was predictive of improved OS (P=0.001), with 36-month OS of 50.5% for patients with BED ≥120 Gy and only 31.6% for patients with BED <120 Gy. On Kaplan-Meier analysis, Charlson score ≥9 was predictive of decreased OS (P=0.04), and BED ≥120 Gy trended towards improved OS (P=0.08). Thirty-two cases of grade <3 toxicity were reported, and only two cases of grade 3 morbidity (fatigue) were noted.

Conclusions

Local control rates for empiric SBRT treatment for hypermetabolic, non-metastatic NSCLC are similar to those for biopsied NSCLC. OS is primarily dependent on a patient’s overall health status, which can be accurately assessed with the Charlson score. BED ≥120 Gy may also contribute to improved OS.

Dose prescription in SBRT for early-stage non-small cell lung cancer: are we all speaking the same language?

INTRODUCTION

Stereotactic body radiation therapy is increasingly used in the treatment of early-stage lung cancers. Guidelines provide indications regarding the constraints to the organs at risk (OARs) and the minimum coverage of the planning target volume but do not suggest optimal dose distribution. Data on dose distribution from the different published series are not comparable due to different prescription modalities and reported dose parameters.

METHODS

We conducted a review of the published data on dose prescription, focusing on the role of homogeneity on local tumor control, and present suggestions on how to specify and report the prescriptions to permit comparisons between studies or between cases from different centers.

CONCLUSIONS

To identify the dose-prescription modality that better correlates with oncologic outcomes, future studies should guarantee a close uniformity of dose distribution between cases and complete dose parameters reporting for treatment volumes and OARs.

Empiric Radiotherapy for Lung Cancer Collaborative Group multi-institutional evidence-based guidelines for the use of empiric stereotactic body radiation therapy for non-small cell lung cancer without pathologic confirmation

The standard of care for managing early stage non-small cell lung cancer (NSCLC) is definitive surgical resection. Stereotactic body radiation therapy (SBRT) has become the standard treatment for patient who are medically inoperable, and it is increasingly being considered as an option in operable patients. With the growing use of screening thoracic CT scans for patients with a history of heavy smoking, as well as improved imaging capabilities, the discovery of small lung nodes has become a common dilemma. As a result, clinicians are increasingly faced with managing lung nodules in patients in whom diagnostic biopsy is not safe or feasible. Herein, we describe the scope of the problem, tools available for predicting the probability that a lung nodule is a malignancy, staging procedures, benefits of pathology-proven and empiric SBRT, considerations of safety based on location of the lesion of concern, and overall efficacy of SBRT.

Clinical outcomes of CyberKnife stereotactic radiosurgery for elderly patients with presumed primary stage I lung cancer

BACKGROUND

In certain situations, especially in the elderly patient population, a tissue diagnosis of a suspected pulmonary neoplasm is not feasible. Often, a definitive treatment such as stereotactic body radiosurgery is recommended, rather than active surveillance. The aim of this study is to evaluate the efficacy and tolerability of stereotactic body radiotherapy (SBRT) for elderly patients with presumed primary stage I lung cancer without pathological tissue confirmation.

METHODS

We performed a retrospective analysis of 25 elderly patients (≥75 years) with presumed primary stage I lung cancer treated with SBRT from 2009-2015. The primary end point was local control (LC); secondary end points were survival and toxicity.

RESULTS

The median follow-up (FU) was 36.0 months (range, 4 to 84 months). The 1-year LC rate was 100%, 3-year LC rate was 78.8%, and 5-year LC rate was 65.7%. The median progression-free survival (PFS) time was 48.0 months (95% CI: 31.2-64.8). The 1-, 3-, and 5-year overall survival (OS) rates were 96.0%, 70.2%, and 50.7%, respectively. The 1-, 3-, and 5-year cancer-specific survival (CSS) rates were 100%, 81.3%, and 67.0%, respectively. No grade 4 or higher toxicity was encountered.

CONCLUSIONS

SBRT is safe and effective treatment for patients with presumed primary stage I lung cancer where obtaining pathological confirmation of malignancy is challenging.

Absence of Pathological Proof of Cancer Associated with Improved Outcomes in Early-Stage Lung Cancer

OBJECTIVES

The purpose of this study was to assess the trends in use of clinical diagnosis and its impact on treatment outcomes in patients receiving radiation therapy for early-stage lung cancer.

METHODS

The Surveillance, Epidemiology, and End Results registry was queried from 2004 to 2012 for patients at least 18 years old in whom stage I (clinical stage T1a-T2a) lung cancer had been diagnosed and who underwent radiation therapy alone. Trends in diagnostic confirmation patterns were characterized. A Cox proportional hazards model was used to assess overall survival, and competing risk regression analysis was used to assess cancer-specific survival (CSS).

RESULTS

A total of 7050 patients were included; the disease of 6399 of them (90.8%) was pathologically diagnosed and that of 651 (9.2%) was clinically diagnosed. There was no significant change in the utilization of clinical versus pathologic diagnosis (p = 0.172) over time. Patients with T1 disease (p < 0.001), tumors 0 to 1.9 cm in size (p < 0.001), and upper lobe tumors (p = 0.004) were more likely to have been clinically diagnosed. On multivariable analysis, clinical diagnosis was associated with an improved CSS (hazard ratio [HR] = 0.82, 95% confidence interval [CI]: 0.71-0.96) but was not associated with an improved overall survival (HR = 1.01, 95% CI: 0.90-1.13). When stratified by T stage, patients whose disease had been clinically diagnosed as stage T1a had an improved CSS (HR = 0.75, 95% CI: 0.58-0.96, p = 0.022). There was a trend toward improved CSS in patients with clinical stage T1b tumors (HR = 0.74, 95% CI: 0.55-1.00, p = 0.052).

CONCLUSIONS

The improved CSS in patients with a clinical diagnosis suggests treatment of benign disease, particularly in smaller tumors. Prudent patient selection is needed to reduce the potential for overtreatment.