Palliative thoracic radiation

Introduction

Patients with advanced lung cancer may experience a variety of symptoms that can cause suffering, including (but not limited to) anxiety, dyspnea, fatigue, nausea, and pain. Palliative radiation to the thorax can ameliorate these symptoms in an attempt to improve quality of life in patients with advanced disease.

The benefits of early palliative care, however, extend beyond mere symptom management. In fact, early palliative care may offer patients meaningful improvements in overall survival. A 2010 study in the New England Journal of Medicine by Temel et al. randomized 151 patients with newly diagnosed, metastatic non–small cell lung cancer to early palliative care incorporated into standard oncologic care versus standard oncologic care alone. Patients who received early palliative care had a longer median survival (11.6 vs. 8.9 months) and higher quality of life. Additionally, they were less likely to experience depressive symptoms (16% vs. 38%) and receive aggressive end-of-life care (33% vs. 54%). Numerous mechanisms have been postulated to explain the increase in survival seen in patients who receive early palliative care. Irwin et al., for example, noted that “[early palliative care] may impact survival by improving [patients’] well-being, comprehensively targeting [quality of life], symptom burden, and depression, by assisting with treatment decision making, and by increasing support.” All patients with advanced lung cancer should receive early, integrated palliative care.

In addition to integrated palliative medical care, patients with advanced cancer may also be candidates for palliative chemotherapy, radiotherapy (RT), and surgery. Palliative RT has been used since the late 19th century to alleviate symptoms in patients with advanced malignancies and is considered to be effective and safe. Palliative RT may prove especially useful in patients with lung cancer, a significant proportion of whom present with locally advanced and metastatic disease. It may help alleviate a number of debilitating symptoms in these patients, including chest pain, cough, and dyspnea.

In this chapter, we will briefly discuss the use of use of palliative radiation therapy in patients with advanced cancers of the thorax. Specifically, we will discuss its use and efficacy in alleviating symptoms in patients with symptomatic thoracic tumors, superior vena cava syndrome, esophageal compression, malignant airway obstruction, and recurrent laryngeal nerve paralysis. We will also discuss the new role of palliative radiation therapy in the treatment of oligometastatic disease which may improve patients’ outcomes.

Thoracic radiation

Thoracic tumors, especially large tumors, can cause symptoms of hemoptysis, pneumonia, bronchial obstruction, cough, dyspnea, and pain. Palliative radiation, given either through external beam radiation therapy or brachytherapy, can help with these symptoms. Radiation is typically delivered to the gross disease in the thorax ( Fig. 13.1 ). The goal of radiation therapy in this situation is to significantly decrease the size of the tumor for as prolonged a period of time as possible.

Various dose-fractionation schedules have been utilized, ranging from 10 Gray (Gy) in 1 fraction to 60 Gy in 30 fractions. A Cochrane meta-analysis did not demonstrate improved survival with the higher dose regimens. However, other studies suggest that higher dose treatments may be associated with improved survival at the cost of increased esophagitis. ^, In general, short course, high dose per fraction regimens are appropriate for patients with poor performance status.

A prospective trial treated 23 symptomatic patients with 17 Gy in two 8.5 Gy fractions delivered 1 week apart. The regimen produced improvements in all symptoms, especially pain, hemoptysis, and dysphagia with minimal toxicity. This very short course of treatment maximizes the amount of time patients with a short, expected life expectancy spend away from medical care.

Moderate doses, such as 30 Gy, might provide the best balance between efficacy and toxicity. Higher dose regimens should only be given to patients who can tolerate the treatment and who have a prolonged expected survival. Other factors such as the inability for the patient to receive chemotherapy or immunotherapy might affect the decision-making process in favor of a more aggressive palliative approach. Special care should be taken to avoid toxicity such as radiation myelitis by limiting the dose to the spinal cord through advanced treatment planning techniques such as three-dimensional conformal radiation therapy (3D-CRT) or intensity modulated radiation therapy (IMRT).

Concurrent chemoRT has also been examined in the setting of palliative thoracic radiation. Three randomized trials have yielded conflicting results. As in definitive treatment, the use of concurrent chemotherapy results in significantly higher rates of esophagitis, neutropenia, and other toxicities. Therefore this treatment regimen can be considered in patients receiving palliative care without distant metastases if their performance status is adequate.

There is likely no role for “prophylactic palliation” of large thoracic tumors. Given the recent encouraging data from the use of immunotherapy and other systemic therapies, these approaches should be utilized initially instead of potentially delaying treatment for many weeks for a course of palliative thoracic RT. Treatment with radiation should be reserved for when a patient becomes symptomatic or the potential benefit of consolidative radiation is considered clinically significant.