Stereotactic Body Radiation Therapy for Liver Metastases: Background and Clinical Evidence
Metastatic liver disease arises most commonly in colorectal, lung, and breast cancers [1]. Modern radiation techniques enable safe delivery of high dose radiation with ablative intent. The data is reviewed in this chapter.
- PDF / 236,347 Bytes
- 11 Pages / 504.567 x 720 pts Page_size
- 81 Downloads / 179 Views
17
Karyn A. Goodman and Arya Amini
17.1 Background and Epidemiology • • Metastatic liver disease arises most commonly in colorectal, lung, and breast cancers [1]. • In colorectal cancer patients up to 15–25 % present with synchronous metastases at diagnosis, and 50–70 % will develop metastases to the liver at some point during their clinical course [2]. • Cancers of the gastrointestinal tract commonly metastasize to the liver due to draining blood supply into the portal circulation. • Historically, metastatic disease to the liver was often treated with systemic therapy alone. • The term “oligometastases” [3, 4], referring to an intermediate stage of metastases where the number and site of metastatic disease is limited and potential local forms of treatment including surgery, radiation, and thermal ablation could be used for curative intent, has changed our approach to liver metastases and
•
•
•
•
K.A. Goodman, MD, MS (*) • A. Amini, MD Department of Radiation Oncology, University of Colorado Cancer Center, 1665 Aurora Court, Room 1032, Aurora, CO 80045, USA e-mail: [email protected]; [email protected]
•
now includes local and systemic treatment options. The rationale for adding local ablative therapies in certain metastatic patient who otherwise have well-controlled systemic disease is that many can progress at sites of increasing tumor burden including the liver. With better combination chemotherapy and targeted agents today, overall response rates have improved by 50 % and have doubled median survival from 10 to 20 months in patients with metastatic colorectal cancer [5]. For patients with well-controlled systemic disease, but liver-dominant metastases, death may result from local progression causing normal liver parenchymal loss and liver failure [6]. Up to 40 % of patients with metastatic colorectal cancer patients have been found to have disease confined to the liver, and 5-year survival for these patients with untreated liver metastases can be less than 3 % [7, 8]. Early surgical series demonstrated a benefit for local therapy in the management of metastatic colorectal cancer to the liver. Prior to the introduction of intensity- modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT), radiation oncologists were limited by the tolerance of the liver to radiation. Older techniques involving portal imaging and radiation to the entire liver have now been replaced with dose conformal IMRT,
© Springer International Publishing AG 2017 T. Hong, P. Das (eds.), Radiation Therapy for Gastrointestinal Cancers, DOI 10.1007/978-3-319-43115-4_17
217
218
image-guided radiation therapy (IGRT), and improved motion management to enable clinicians to deliver ablative SBRT. • SBRT local control rates are now exceeding 90 % in modern series.
17.2 Local Therapy Options 17.2.1 Surgical Resection • Initial reports in the 1980s and 1990s of surgically resected liver metastases demonstrated encouraging outcomes with 5-year overall survival rates ranging from 30–60 % [9–11
Data Loading...
