Radiation Therapy for Metastatic Disease

Abstract

Bone metastases occur in up to 40% of NSCLC patients. If associated with pathological fractures or metastatic spinal cord compression (MSCC), they are considered “complicated” lesions. Otherwise, they are considered “uncomplicated”. 1x8 Gy of radiation therapy (RT) can be considered the standard treatment of most uncomplicated painful bone metastases. Single-fraction RT requires re-RT more often than multi-fraction RT regimens. However, re-RT after 1x8 Gy is safe and effective. If re-RT is required after longer-course RT with 10x3 Gy or 20x2 Gy, the second RT course should be delivered using high-precision techniques. For a pathological fracture, surgical stabilisation followed by RT should be performed. Remineralization of the osteolytic bone is better after multi-fraction RT. For MSCC, short-course RT is as effective as longer RT programs regarding motor function. Local control of MSCC is better after longer-course RT. Patients with MSCC from NSCLC and a favorable survival prognosis may be considered candidates for decompressive surgery followed by longer-course RT. Decompressive surgery would also be the first choice for a local recurrence of MSCC after longercourse RT. A recurrence after short-course RT can be safely treated with another short-course of RT. Brain metastases occur in 20–40% of cancer patients. NSCLC is the most common primary tumor and which accounts for at least 40% or more of these patients. Most patients have multiple (4) lesions and usually receive whole-brain radiotherapy (WBRT) alone. Patients with a poor survival prognosis should receive 5x4 Gy in one week, whereas patients with a more favourable prognosis are candidates for longer-course WBRT. Patients with 1–3 brain metastases have a considerably better survival prognosis and may benefit from more intensive treatments including radiosurgery or surgery. WBRT in addition to radiosurgery or surgery leads to improved local control. The non-invasive regimen radiosurgery + WBRT is at least as effective as surgery + WBRT, and, therefore, preferable. Most data of SBRT of liver metastases have been obtained from colorectal cancer patients bur can be “extrapolated” to liver metastases from NSCLC. SBRT if used for a limited number of liver metastases can lead to high local control rates and considered a reasonable alternative to other local treatments. If SBRT is used for the treatment of lung metastases, lung tissue density correction during treatment planning is very important. In the treatment of a limited number of lung metastases, SBRT can result in excellent local control rates and median survival times of more than three years. In summery, radiation therapy if appropriately tailored to the individual patient with metastasis from NSCLC can provide valuable results in terms of relief of symptoms and improvement of the patient’s prognosis.KeywordsBrain MetastasisStereotactic Body Radiation TherapyLocal Control RateBiologically Effective DoseSurvival PrognosisThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.