An Overview of the Role of Radiotherapy in the Treatment of Small Cell Lung Cancer - A Mainstay of Treatment or a Modality in Decline?

Real-World Analysis of Treatment Patterns in Limited-Stage Small Cell Lung Cancer: Implications for Clinical Practice

BACKGROUND

Unresolved issues complicate treating limited-stage small-cell lung cancer (LS-SCLC). We conducted a real-world study analyzing LS-SCLC treatment patterns to address clinical needs.

METHODS

We retrospectively enrolled patients with LS-SCLC treated at Peking Union Medical College Hospital between May 2008 and December 2023. Information was collected on clinicopathological features, cancer-related treatments, laboratory test results, and clinical and prognostic data. Kaplan-Meier survival analysis was performed to evaluate progression-free (PFS) and overall survival (OS). Cox regression models were used to assess the factors influencing survival.

RESULTS

Among the 203 patients with LS-SCLC, the median OS (mOS) was 28.8 months. Log-rank testing revealed significant mOS differences among radiotherapy timing groups (p = 0.031): concurrent chemoradiotherapy (cCRT) 30.1 months, sequential therapy 27.5 months, and no radiotherapy 21.7 months. Early cCRT showed a non-significant mOS trend advantage over late cCRT (38.3 vs. 29.5 months, p = 0.058). Prophylactic cranial irradiation (PCI) demonstrated comparable mOS (36.9 vs. 29.6 months, p = 0.27). Peripheral blood biomarkers (PBBs) lacked prognostic significance. Multivariate analysis identified Eastern Cooperative Oncology Group (ECOG) performance status (PS) > 1 (HR = 3.652, 95% CI 1.579-8.448; p = 0.002) and N2/N3 metastasis (N2: HR = 2.872, 95% CI 1.312-6.286, p = 0.008; N3: HR = 2.645, 95% CI 1.195-5.856, p = 0.016) as survival predictors. Sequential radiotherapy increased mortality risk versus early cCRT (HR = 1.701, 95% CI 1.125-2.573; p = 0.012).

CONCLUSIONS

Performance status and lymph node metastasis are prognostic factors for patients with LS-SCLC. cCRT improves the prognosis of LS-SCLC, with early cCRT providing a significant survival benefit and late cCRT being an acceptable option.

Developing a predictive model and uncovering immune influences on prognosis for brain metastasis from lung carcinomas

Objective

Primary lung carcinomas (LCs) often metastasize to the brain, resulting in a grim prognosis for affected individuals. This population-based study aimed to investigate their survival period and immune status, while also establishing a predictive model.

Methods

The records of 86,763 primary LCs from the Surveillance, Epidemiology, and End Results (SEER) database were extracted, including 15,180 cases with brain metastasis (BM) and 71,583 without BM. Univariate and multivariate Cox regression were employed to construct a prediction model. Multiple machine learning methods were applied to validate the model. Flow cytometry and ELISA were used to explore the immune status in a real-world cohort.

Results

The research findings revealed a 17.49% prevalence of BM from LCs, with a median survival of 8 months, compared with 16 months for their counterparts (p <0.001). A nomogram was developed to predict survival at 1, 3, and 5 years on the basis of these variables, with the time-dependent area under the curve (AUC) of 0.857, 0.814, and 0.786, respectively. Moreover, several machine learning approaches have further verified the reliability of this model's performance. Flow cytometry and ELISA analysis suggested the prediction model was related the immune status.

Conclusions

BM from LCs have an inferior prognosis. Considering the substantial impact of these factors, the nomogram model is a valuable tool for guiding clinical decision-making in managing patients with this condition.

Prophylactic cranial irradiation for small cell lung cancer in the era of immunotherapy and molecular subtypes

PURPOSE OF REVIEW

Small cell lung cancer (SCLC) is an aggressive disease with a poor prognosis, whereas its metastatic capacity carries a predilection for the brain. Although prophylactic cranial irradiation (PCI) has been used to address this problem, upcoming alternatives might necessitate reflection of its application in SCLC treatment.

RECENT FINDINGS

The addition of immunotherapy to treatment guidelines has provided a new strategy for the management of brain metastases. Complementation of immunotherapy with active MRI surveillance could potentially replace PCI and avoid irradiation-related cognitive side effects. SCLC's molecular profile is heterogeneous, with differential response to treatment modalities between subgroups. Investigation of these variances might be essential to improve therapeutic outcomes in SCLC patients.

SUMMARY

The role of PCI in SCLC treatment must be examined in light of immunotherapy. We summarize recent results, bearing SCLC subtypes and therapeutic vulnerabilities in mind, to derive tailored treatment strategies for SCLC patients in future settings.

Mathematical Modeling Support for Lung Cancer Therapy-A Short Review

The paper presents a review of models that can be used to describe dynamics of lung cancer growth and its response to treatment at both cell population and intracellular processes levels. To address the latter, models of signaling pathways associated with cellular responses to treatment are overviewed. First, treatment options for lung cancer are discussed, and main signaling pathways and regulatory networks are briefly reviewed. Then, approaches used to model specific therapies are discussed. Following that, models of intracellular processes that are crucial in responses to therapies are presented. The paper is concluded with a discussion of the applicability of the presented approaches in the context of lung cancer.

Volumetric-Modulated Arc-Based Re-radiosurgery With Simultaneous Reduced-Dose Whole-Brain Irradiation for Local Failures Following Prior Radiosurgery of Brain Oligometastases From Small Cell Lung Cancer

First-line and possibly repeated stereotactic radiosurgery (SRS) with preserving whole-brain radiotherapy (WBRT) is an attractive and promising option for synchronous or metachronous limited brain metastases (BMs) from small cell lung cancer (SCLC), for which a modest prescription dose is generally preferred, such as a biological effective dose of ≤60 Gy, based on the linear-quadratic formula with an alpha/beta ratio of 10 (BED10). In addition, the optimal planning scheme for re-SRS for local progression after SRS of BMs from SCLC remains unclear. Herein, we describe a case of limited BMs developing after a partial response to standard chemoradiotherapy (CRT) for limited-stage SCLC. The BMs, including local failures following prior single-fraction (fr) SRS, were re-treated with volumetric-modulated arc-based SRS combined with simultaneous reduced-dose WBRT. The first SRS with 36.3 Gy/3 fr (BED10 80 Gy) for a small BM resulted in a local control of 17.2 months. However, the second SRS with 20 Gy/1 fr (BED10 60 Gy) to the 60% or 85% isodose surface (IDS) covering the gross tumor volume (GTV) of three new BMs with a paradoxical T1/T2 mismatch, that is, a visible mass on T2 larger than an enhancing area, resulted in partial symptomatic local progression of all lesions within 5.2 months, along with the development of two new lesions, despite continued amrubicin monotherapy. In contrast, the third SRS with 53 Gy/10 fr (BED10 81 Gy) to ≤74% IDSs encompassing the GTV boundary resulted in complete responses of all the lesions during six months. However, despite a combined use of WBRT of 25 Gy in the third SRS, symptomatic spinal cerebrospinal fluid dissemination and new BMs developed, the former leading to patient mortality. A BED10 of ≥80 Gy to the GTV margin and a steep dose increase inside the GTV boundary are suitable to ensure excellent local control in SRS for SCLC BMs. Re-SRS with the aforementioned scheme can be an efficacious option for local failures following prior SRS with a BED10 of ≤60 Gy. Modest dose escalation with a simultaneous integrated boost to bulky lesions in the initial CRT may reduce the development of new BM through improved control of the potential source.

Twenty-Month Regression Following Concurrent Conventional Whole-Brain Irradiation and Chemoimmunotherapy for ≥3.8 cm Cerebellar Metastasis From Small Cell Lung Cancer

Standard whole-brain radiotherapy (WBRT) alone for large brain metastases (BMs) from small cell lung cancer (SCLC) has limited efficacy and durability, and stereotactic radiosurgery (SRS) alone for symptomatic posterior fossa BMs >3 cm with satellite lesions is challenging. Herein, we describe the case of a 73-year-old female presenting with treatment-naïve SCLC and 15 symptomatic multiple BMs, including a ≥3.8-cm cerebellar mass (≥17.7 cm3) and two adjacent lesions; otherwise, the SCLC was confined to the thorax. The patient was initially treated concurrently with conventional WBRT (30 Gy in 10 fractions) without boost and chemoimmunotherapy (CIT) consisting of carboplatin, etoposide, and atezolizumab. Atezolizumab was excluded during irradiation. Five months after WBRT, the large cerebellar lesion had remarkably regressed, and the smaller lesions (≤17 mm) showed complete responses (CRs) without local progression at 20 months. However, six and 16 months after WBRT, the thoracic lesions had progressed, and although amrubicin was administered, four new BMs, including pons involvement, had developed, respectively. Despite the CRs of the four BMs following SRS (49.6 Gy in eight fractions) and the sustained regression of the thoracic lesions, meningeal dissemination and multiple new BMs were evident 3.5 months post-SRS. The small remnant of the large BM and/or newly developed BMs abutting the cerebrospinal fluid (CSF) space could have led to CSF dissemination, the presumed cause of the patient's death. Taken together, concurrent chemo-WBRT and subsequent CIT can provide excellent and durable tumor responses for SCLC BMs, but may not be fully sufficient for BMs ≥3.8 cm. Therefore, in cases with large lesions, focal dose escalation of the large lesions, consolidative thoracic radiotherapy, and dose de-escalation in the macroscopically unaffected brain region may prevent or attenuate CSF dissemination, new BM development, and adverse effects and thus should be considered.

Combined radiotherapy and immune checkpoint inhibition for the treatment of advanced hepatocellular carcinoma

Hepatocellular Carcinoma (HCC) is one of the most common cancers and a leading cause of cancer related death worldwide. Until recently, systemic therapy for advanced HCC, defined as Barcelona Clinic Liver Cancer (BCLC) stage B or C, was limited and ineffective in terms of long-term survival. However, over the past decade, immune check point inhibitors (ICI) combinations have emerged as a potential therapeutic option for patients with nonresectable disease. ICI modulate the tumor microenvironment to prevent progression of the tumor. Radiotherapy is a crucial tool in treating unresectable HCC and may enhance the efficacy of ICI by manipulating the tumor microenvironment and decreasing tumor resistance to certain therapies. We herein review developments in the field of ICI combined with radiotherapy for the treatment of HCC, as well as look at challenges associated with these treatment modalities, and review future directions of combination therapy.