Stereotactic body radiation therapy for early-stage non-small-cell lung cancer in octogenarians and older: an alternative treatment

Is SBRT the optimal first-line treatment for operable early-stage NSCLC in elderly patients?

The introduction of screening programs and the increase in life expectancy in developed countries have significantly raised the incidence of early-stage non-small cell lung cancer (ES-NSCLC). Surgery remains the standard of care for ES-NSCLC; however, stereotactic body radiotherapy (SBRT) has become the treatment of choice for patients with inoperable ES-NSCLC. Despite its growing use, there is a lack of robust data from randomized phase III trials comparing SBRT to surgery, mostly due to challenges in recruitment. This gap is particularly pronounced in the elderly, who are often excluded from clinical studies. With the rising incidence of ES-NSCLC and an aging population, non-invasive therapies like SBRT may offer significant advantages by minimizing treatment-related morbidity while effectively controlling the disease. This review critically evaluates the current literature on managing ES-NSCLC in elderly patients and assesses the potential benefits and limitations of SBRT as a standard of care in this complex population.

Stereotactic body radiation therapy for clinically diagnosed early-stage non-small cell lung cancer: Importance of accurate CT interpretation by experts

Introduction

This study evaluated the clinical outcomes of stereotactic body radiotherapy (SBRT) for both pathologically diagnosed (PD) and clinically diagnosed (CD) early-stage non-small cell lung cancer (NSCLC) and explored the significance of accurate expert computed tomography (CT) interpretation.

Methods

We retrospectively analyzed 95 patients with early-stage NSCLC who received SBRT at our institution. Patients were classified into CD and PD groups. Two chest radiologists retrospectively interpreted the pre-SBRT CT images to determine the tumor subtype and probability of malignancy (PM). Clinical findings, CT features, and treatment outcomes were compared between the two groups. The survival rate of the CD group was analyzed separately according to the PM grade.

Results

Median overall survival for the CD and PD groups was 6.0 and 5.4 years (P = 0.57), respectively. Median cause-specific survival was 10.2 years in the CD group and not reached in the PD group (P = 0.76). In the CD group, lung cancer mortality was lower in the low PM group (25% [1 of 4]) than in the high PM group (47.4% [9 of 19]).

Conclusion

It may be desirable to evaluate the PM of the nodule using expert CT interpretation to decide whether SBRT is indicated in CD early-stage NSCLC.

Treatment and mortality risk of older adults with non-small cell cancer in Taiwan: A population-based cohort study

BACKGROUND

Older patients tend to have decreased physical functions and more comorbidities than younger patients. At present, the best management for very elderly patients with lung cancer is not known. In this study, we aimed to investigate treatment and mortality risk of older adults with non-small cell cancer (NSCLC) in Taiwan.

METHODS

This study analyzed data from the Taiwan Cancer Registry database. Patients aged ≥80 years with newly diagnosed NSCLC between 2010 and 2017 were included. Treatment options were categorized as curative, palliative, and no treatment. Patients were followed up until death or December 31, 2020. Univariable and multivariable Cox proportional hazards models were used to estimate mortality risk, and Kaplan-Meier survival curves were drawn.

RESULTS

A total of 11 941 patients, aged ≥80 years, with newly diagnosed NSCLC between 2010 and 2017 were identified from the Taiwan Cancer Registry and followed up until 2020. The mean age was 84.4 ± 3.7 years old, and 7468 (62.54%) were men. The Kaplan-Meier survival curves showed significant differences across the three treatment options (log-rank p < 0.001). Results from multivariate Cox regression demonstrated that patients on palliative treatment (adjusted HR: 0.52, 95% CI: 0.48-0.56, p < 0.001) and curative treatment (adjusted HR: 0.45, 95% CI: 0.42-0.48, p < 0.001) had a significantly lower mortality risk than those with no treatment. The subgroup analyses stratified by cancer stages also showed consistent findings.

CONCLUSION

Elderly patients with NSCLC had significantly decreased mortality risk when receiving curative or palliative treatment compared with those without treatment. In the future, further studies are warranted to investigate complications and quality of life of elderly patients with NSCLC during palliative or curative treatment.

Translational study for stereotactic body radiotherapy against non-small cell lung cancer, including oligometastases, considering cancer stem-like cells enable predicting clinical outcome from in vitro data

BACKGROUND

Curative effects of stereotactic body radiotherapy (SBRT) for non-small cell lung cancer (NSCLC) have been evaluated using various biophysical models. Because such model parameters are empirically determined based on clinical experience, there is a large gap between in vitro and clinical studies. In this study, considering the heterogeneous cell population, we performed a translational study to realize the possible linkage based on a modeling approach.

METHODS

We modeled cell-killing and tumor control probability (TCP) considering two populations: progeny and cancer stem-like cells. The model parameters were determined from in vitro survival data of A549 and EBC-1 cells. Based on the cellular parameters, we predicted TCP and compared it with the corresponding clinical data from 553 patients collected at Hirosaki University Hospital.

RESULTS

Using an all-in-one developed model, the so-called integrated microdosimetric-kinetic (IMK) model, we successfully reproduced both in vitro survival after acute irradiation and the 3-year TCP with various fractionation schemes (6-10 Gy per fraction). From the conventional prediction without considering cancer stem cells (CSCs), this study revealed that radioresistant CSCs play a key role in the linkage between in vitro and clinical outcomes.

CONCLUSIONS

This modeling study provides a possible generalized biophysical model that enables precise estimation of SBRT worldwide.

Surgery versus radiotherapy in octogenarians with stage Ia non‑small cell lung cancer: propensity score matching analysis of the SEER database

Objectives

To compare overall survival (OS) and cancer-specific survival (CSS) outcomes of surgery with radiotherapy in octogenarians with stage Ia non-small cell lung cancer (NSCLC).

Materials and methods

Patients aged ≥ 80 years with clinical stage Ia (T1N0M0) NSCLC between 2012 and 2017 were identified from the population-based Surveillance, Epidemiology, and End Results (SEER) database. Patients were assigned into surgery and radiotherapy groups. Multivariate Cox regression analysis was used to identify survival-associated factors. Treatment groups were adjusted by propensity score matching (PSM) analysis while OS and CSS outcomes were compared among groups by Kaplan–Meier analysis.

Results

A total of 1641 patients were identified, with 46.0% in the surgical group and 54.0% in the radiotherapy group. Compared to surgery, radiotherapy-treated patients were older, later diagnosed, had more often unmarried, more squamous cell carcinoma, more unknown grade and increased tumor sizes. Radiotherapy was associated with a significantly worse OS, compared to surgery (hazard ratio 2.426; 95% CI 2.003–2.939; P < .001). After PSM, OS (P < 0.001) and CSS (P < 0.001) were higher in the surgery group. The 1-, 3-, and 5-year OS rates of surgical and radiotherapy group were 90.0%, 76.9%, 59.9%, and 86.0%, 54.3%, 28.0%, respectively. The 1-, 3-, and 5-year CSS rates of surgical and radiotherapy group were 94.5%, 86.1%, 78.0% and 90.7%, 74.5%, 61.0%, respectively. There were no survival differences between the matched surgery without lymph node examination (LNE) and radiotherapy group, as well as between the matched surgery and radiotherapy who were recommended but refused surgery group.

Conclusions

In octogenarians with stage Ia NSCLC, surgery with lymph node dissection offers better OS and CSS outcomes than radiotherapy.

Stereotactic Ablative Radiotherapy in the Treatment of Early-Stage Lung Cancer - A Done Deal?

Stereotactic ablative radiotherapy (SABR) is an important curative-intent treatment option for early-stage non-small cell lung cancer. It offers good cancer control without invasive surgery and has become the standard of care for medically inoperable patients. The literature on SABR for early-stage non-small cell lung cancer is substantial and continues to grow. However, there remain areas of controversy where data are limited - notably the use of SABR in medically operable patients. Other areas of some debate include the treatment of central/ultra-central and large (>5 cm) lesions, as well as treatment with co-existing interstitial lung disease. This review article provides an overview of the current literature together with a discussion of future directions.

Dosimetric comparison of Synchrony® real-time motion tracking treatment plans between CyberKnife robotic radiosurgery and Radixact system for stereotactic body radiation therapy of lung and prostate cancer

The aim of this study was to assess which machine, Radixact or CyberKnife, can deliver better treatment for lung and prostate stereotactic body radiation therapy (SBRT) with the use of Synchrony® real-time motion tracking system. Ten and eight patients treated with lung and prostate SBRT, respectively, using the CyberKnife system were selected for the assessment. For each patient, a retrospective Radixact plan was created and compared with the original CyberKnife plan. There was no statistically significant difference in the new conformity index of the Radixact plans and that of the Cyberknife plans in both lung and prostate SBRT. The average homogeneity index in the Radixact plans was better in both lung and prostate SBRT with statistical significance (p = 0·04 for lung and p = 0·02 for prostate). In lung SBRT, the dose to lungs was lower in Cyberknife plans (p = 0·002). In prostate SBRT, there was no statistically significant difference in organs at risk sparing between Cyberknife plans and Radixact plans. In conclusion, CyberKnife was better in lung SBRT while Radixact was better in prostate SBRT.

Identification of novel prognostic factors focusing on clinical outcomes in patients with non-small cell lung cancer after stereotactic body radiotherapy

Stereotactic body radiotherapy (SBRT) has attracted extensive attention as an effective treatment for patients with early-stage non-small cell lung cancer. However, the factors affecting prognosis after SBRT have not been fully elucidated. The aim of the present study was to investigate the prognostic factors associated with overall survival (OS) and local control (LC) after SBRT. Between March 2003 and March 2020, 497 patients with primary or oligo-metastatic lung cancer who underwent SBRT treatment were retrospectively reviewed. Univariate analysis was performed against various factors related to patient and tumor characteristics using Kaplan-Meier method. Furthermore, the factors with statistically significant differences identified via univariate analysis underwent a stratified Cox proportional hazard regression analysis. The median follow-up period for all patients was 26.17 months (range, 0.36-194.37), and the 5-year OS and LC rates were 66.3 and 86.0%, respectively. Multivariate analysis showed that surfactant protein-D (SP-D), tumor CT values (TCTV) and iodine density values (IDV) were independent prognostic factors for OS, and histology, TCTV and IDV were for LC. Although histology was not selected as a prognostic factor related to OS, it was indicated that patients with squamous cell carcinoma were associated with the SP-D high group compared with the SP-D normal group. In addition, TCTV was correlated to water density values, which tended to decrease with increasing IDV. From these findings, SP-D and TCTV were identified as potential new candidate prognostic factors after SBRT, and it is possible that combining SP-D and histology, and TCTV and IDV may improve the accuracy of prognostic prediction.

Stereotactic body radiation therapy for an octogenarian with pulmonary carcinosarcoma

Pulmonary carcinosarcoma is a rare lung tumor accounting for <1% of primary lung cancers, characterized by biphasic components with both carcinomatous and sarcomatous mesenchymal features. This report describes a case of pulmonary carcinosarcoma in an octogenarian who was treated with stereotactic body radiation therapy (SBRT) and whose therapeutic response was sustained for 2 years. Along with other treatment modalities, SBRT might be considered for the treatment of medically inoperable localized stage pulmonary carcinosarcoma.

Lung stereotactic body radiation therapy for elderly patients aged ≥ 80 years with pathologically proven early-stage non-small cell lung cancer: a retrospective cohort study

Background

Stereotactic body radiation therapy (SBRT) is an established therapy for medically inoperable early-stage non-small cell lung cancer (NSCLC). Many elderly patients are medically inoperable owing to comorbidities. Therefore, SBRT may be a useful therapy for elderly patients. However, the application of SBRT for patients aged ≥ 80 years has not been completely elucidated. Therefore, this study aimed to assess the clinical utility of SBRT for elderly patients aged ≥ 80 years with pathologically proven early-stage NSCLC.

Methods

We retrospectively evaluated the data of patients aged ≥ 80 years with pathologically proven primary NSCLC who underwent SBRT at our institution between January 2009 and March 2020. Treatment outcomes and toxicities were analyzed. We used the Kaplan–Meier method to estimate survival curves and the log-rank test to compare the survival curves. We performed univariate and multivariate Cox regression analyses. p-values < 0.05 were regarded significant.

Results

Sixty-four patients (65 lesions) were included, and the median follow-up period was 38.7 (range 3.5–95.7) months. The median age was 82.9 (range 80.0–94.8) years. Sixteen patients were medically operable, and 48 patients were medically inoperable. The prescribed dose of SBRT was either 48 Gy in four fractions or 60 Gy in 10 fractions. The median survival time was 60.0 months (95% confidence interval, 43.5–71.1). The 1-, 3-, and 5-year local control, cancer-specific survival, progression-free survival, and overall survival rates were 98.4%, 98.4%, 81.0%, and 88.9%; 90.1%, 93.7%, 58.9%, and 68.3%; and 87.4%, 83.5%, 38.2%, and 47.5%, respectively. Multivariate analysis revealed that inoperability and solid nodules were the predictors of poor overall survival after SBRT in elderly patients. Two patients (3.1%) had grade 3 radiation pneumonitis, and one patient (1.6%) had grade 5 radiation pneumonitis.

Conclusions

SBRT was feasible in patients aged ≥ 80 years with NSCLC. It achieved good local control with minimal toxicity. SBRT may be beneficial in elderly patients with early-stage NSCLC.