Stereotactic body radiotherapy versus conventional radiotherapy for early-stage small cell lung cancer

New perspectives in the management of small cell lung cancer

The treatment of small cell lung cancer (SCLC) is a challenge for all specialists involved. New treatments have been added to the therapeutic armamentarium in recent months, but efforts must continue to improve both survival and quality of life. Advances in surgery and radiotherapy have resulted in prolonged survival times and fewer complications, while more careful patient selection has led to increased staging accuracy. Developments in the field of systemic therapy have resulted in changes to clinical guidelines and the management of patients with advanced disease, mainly with the introduction of immunotherapy. In this article, we describe recent improvements in the management of patients with SCLC, review current treatments, and discuss future lines of research.

Radiation and Systemic Therapy for Limited-Stage Small-Cell Lung Cancer

Progress in the overall treatment of small-cell lung cancer (SCLC) has moved at a slower pace than non-small-cell lung cancer. In fact, the standard treatment regimen for limited stage SCLC has not appreciably shifted in more than 20 years, consisting of four to six cycles of cisplatin and etoposide chemotherapy concurrent with thoracic radiotherapy (TRT) followed by prophylactic cranial irradiation (PCI) for responsive disease. Nevertheless, long-term outcomes have improved with median survival approaching 25-30 months, and approximately one third of patients now survive 5 years. This is likely attributable in part to improvements in staging, including use of brain magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography imaging, advances in radiation treatment planning, and supportive care. The CONVERT and CALGB 30610 phase III trials failed to demonstrate a survival advantage for high-dose, once-daily TRT compared with standard 45 Gy twice-daily TRT, although high-dose, once-daily TRT remains common in practice. A phase III comparison of high-dose 60 Gy twice-daily TRT versus 45 Gy twice-daily TRT aims to confirm the provocative outcomes reported with 60 Gy twice daily in the phase II setting. Efforts over time have shifted from intensifying PCI, to attempting to reduce treatment-related neurotoxicity, to more recently questioning whether careful magnetic resonance imaging surveillance may obviate the routine need for PCI. The addition of immunotherapy has resulted in mixed success in extensive-stage SCLC with modest benefit observed with programmed death-ligand 1 inhibitors, and several ongoing trials assess programmed death-ligand 1 inhibition concurrent or adjuvant to chemoradiotherapy in limited-stage SCLC. Major advances in future treatment will likely depend on a better understanding and exploiting of molecular characteristics of SCLC with increasing personalization of therapy.

First-Line Anlotinib Combined with Stereotactic Body Radiation Therapy for an Octogenarian with Pulmonary Carcinosarcoma

Pulmonary carcinosarcoma (PC) is a rare and highly malignant type of non-small cell lung cancer (NSCLC) that is insensitive to radiotherapy and chemotherapy and has a poor prognosis. Here, we report a case of an 88-year-old patient with inoperable PC and a history of cerebral infarction who was treated with first-line anlotinib combined with stereotactic body radiation therapy (SBRT). The therapeutic response has sustained for 10 months. Our work suggests that SBRT combined with anlotinib may be a safe and effective treatment strategy for octogenarians with PC.

Stereotactic ablative radiotherapy in T1-2N0M0 small cell lung cancer: A systematic review and meta-analysis

OBJECTIVES

Stereotactic ablative radiotherapy (SABR) is used to treat inoperable early-stage, node-negative small cell lung cancer (SCLC). We performed a systematic review and meta-analysis of the literature on SABR for T1-2N0M0 SCLC to summarize outcomes including local control (LC), overall survival (OS), recurrence rates, and toxicity.

MATERIALS AND METHODS

This study was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) and MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines. A systematic review of PubMed and EMBASE (inception to April 2021) was conducted. Two authors independently reviewed articles for inclusion and extracted study-level data. Random-effects meta-analysis was conducted using R (version 3.6.2) at a significance threshold of 0.05.

RESULTS

Eleven studies were identified in the systematic review and seven (399 patients) were selected for meta-analysis. Inoperability was noted as the indication for SABR in 94% (75-100%) of patients. Median follow-up and tumor size were 19.5 months (11.9-32) and 24 mm (19-29), respectively. Chemotherapy and PCI use rates were 44.1% (95% confidence interval [CI], 27.0-61.9%) and 13.8% (95% CI, 0.4-41.2%), respectively. Local control was 97.3% (95% CI, 92.3-99.8%) at 1 year and 95.7% (95% CI, 74.2-100.0%) at 2 years. Overall survival was 86.3% (95% CI, 74.4-94.9%) at 1 year and 63.7% (95% CI, 45.7-79.9%) at 2 years. Nodal and distant recurrence rates were 17.8% (95% CI, 7.5-31.2%) and 26.9% (95% CI, 7.4-53.0%), respectively. The rates of grade 1, grade 2, and grade 3 toxicity (CTCAE) were 12.6% (95% CI, 6.7-19.9%), 6.7% (95% CI, 3.3-11.2%), and 1.4% (95% CI, 0.0-5.3%), respectively. No grade 4 or 5 events were observed across the studies.

CONCLUSION

SABR for inoperable early-stage, node-negative SCLC is locally effective with limited toxicity. Prospective studies are required to further evaluate the role of SABR for patients at higher risk of toxicity with surgery or combined chemoradiation.

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.

The current role of surgery and SBRT in early stage of small cell lung cancer

BACKGROUND

Early stage small cell lung cancer (T1-2N0M0SCLC) represents 7% of all SCLC. The standard treatment in patients with intrathoracic SCLC disease is the use of concurrent chemoradiotherapy (CRT). Nowadays, the recommended management of this highly selected group is surgical resection due to favorable survival outcomes. For medically inoperable patients or those who refuse surgery, there is an increasing interest in evaluating the role of Stereotactic Body Radiotherapy (SBRT) for T1-2N0SCLC, transferring the favorable experience obtained on inoperable NSCLC (Non-Small-cell Lung Cancer). In the era of multimodality treatment, adjuvant systemic therapy plays an important role even in the management of early SCLC, increasing the disease-free survival (DFS) and Overall Survival (OS). The benefit of Prophylactic Cranial Irradiation (PCI), that currently has a Category I recommendation for localized stage SLCL, remains controversial in this selected subgroup of patients due to the lower risk of brain metastasis.

AIM

This review summarizes the most relevant data on the local management of T1-2N0M0SCLC (surgery and radiotherapy), and evaluates the relevance of adjuvant treatment.

RELEVANCE FOR PATIENTS

Provides a critical evaluation of best current clinical management options for T1-2N0M0 SCLC.