The role of the surgeon in the management of oligometastatic non-small cell lung cancer: a literature review

Abstract

In this review, we aim to summarize the most recent data on the surgical management of oligometastatic non-small cell lung cancer (NSCLC).Background: Approximately 60-70% of all patients with NSCLC initially present with advanced stages of cancer at time of diagnosis. These patients are generally treated with chemotherapy, radiation therapy, or a combination of these modalities. Patients with late-stage disease are usually not considered to be amenable for curative-intent treatments due to poor prognoses. Despite advances in systemic therapies, 5-year overall survival rates in these patients remain poor. However, technological advances in imaging modalities and new imaging strategies have substantially increased tumor detection rates and have resulted in a shift towards earlier diagnosis of NSCLC, possibly in stages in which metastatic disease is limited and still treatable.Studies in recent years have shown that there is a distinct group of patients with metastatic lesions at one or a few sites, often referred to as oligometastatic disease, that may have better survival outcomes compared to patients with more disseminated diseases. Furthermore, it is suggested that these patients may benefit from a combination of systemic treatment and local treatment aimed at the metastatic site(s). However, the role of surgery in this setting remains a controversial subject, with many unanswered questions.Methods: The PubMed/MEDLINE database and the Cochrane database were searched to find relevant articles regarding oligometastatic NSCLC. Specifically, articles regarding definitions of oligometastatic disease, oligometastatic tumor biology, diagnosis, and the treatment of oligometastatic disease were identified.Conclusions: Oligometastatic NSCLC represents a wide spectrum of diseases and encompasses a heterogeneous patient population. Current data suggests that local ablative treatment of oligometastatic lesions with surgery or stereotactic body radiation therapy may result in improved overall survival and progression-free survival rates. However, more data from multi-center prospective trials are necessary to shed light on which therapeutic modalities are most suitable for the treatment of oligometastatic NSCLC.Integration of clinical and molecular staging data is necessary to allow for more personalized treatment approaches.

Patient Selection for Local Aggressive Treatment in Oligometastatic Non-Small Cell Lung Cancer

“…Currently, there is no clear consensus on the number of metastatic lesions and number of involved organs that define an oligometastatic state [ 10 ]. The majority of published phase II–IV clinical trials on the treatment of oligometastatic NSCLC have used five or fewer metastases in two or fewer organs as a threshold for oligometastasis [ 11 ].…”

“…The majority of published phase II–IV clinical trials on the treatment of oligometastatic NSCLC have used five or fewer metastases in two or fewer organs as a threshold for oligometastasis [ 11 ]. Current evidence on LAT in oligometastatic disease is, therefore, limited by the heterogeneous definition and varying inclusion criteria of prospective trials [ 10 ]. Due to these controversies, the European Organization of Research and Treatment of Cancer (EORTC) formed a multidisciplinary, pan-European consensus group in 2019 to determine the definition of synchronous oligometastatic NSCLC in a multistep consensus process [ 12 ].…”

“…Patients with diffuse serosal metastases (meningeal, pericardial, pleural, or peritoneal) or bone marrow involvement are as well excluded from the definition of oligometastatic NSCLC, for they cannot be treated with radical intent [ 12 ]. In general, most (oligo) metastases of NSCLC are found in the brain (35.5%), followed by the contralateral lung (33.6%), the adrenal glands (10%), bones (8.5%), and the liver (2.4%) [ 10 , 13 ]. In addition to the definition of the oligometastatic stage, the EORTC consortium formulated recommendation for the staging work-up.…”

“…Berzenji et al recently summarized the two most common treatment approaches: The first approach ( Figure 1 B) includes an initial aggressive resection of the primary tumor, followed by the resection or SBRT of metastatic lesions. Systemic treatment (preferably targeted treatment in NSCLC with targetable oncogenic drivers or immunotherapy in NSCLC without targetable oncogenic drivers but PD-L1 expression >1%) is subsequently used for the control of micrometastatic disease [ 10 ]. A second option for addressing oligometastatic NSCLC is a neoadjuvant systemic treatment as described above, followed by a PET-CT-based re-staging and subsequent resection ( Figure 1 A).…”

“…In this stage, a metastatic disease might be amenable to local aggressive therapy (LAT), which may include surgical resection of the primary tumor and metastatic lesions and/or a stereotactic body radiation therapy (SBRT). This new concept resulted in a paradigm shift where metastatic NSCLC would not per definition be incurable but require a multi-disciplinary treatment approach to address both the localized primary and metastatic tumor lesions, as well as disseminated, circulating tumor cells [ 10 ]. With this approach, the course of the disease may be modified and long-term cancer control may be achieved.…”