Unveiled Findings Reveal Underacknowledged and Unwelcomed Aspects of Cancer Therapy
A groundbreaking report published by the National Council on Radiation Protection and Measurements (NCRP) has shed light on the long-term health effects of radiation therapy in cancer treatment. The report, led by Lois B. Travis, M.D., Sc.D., from the University of Rochester Medical Center, highlights several important issues based on extensive research and clinical follow-up of cancer survivors.
The report focuses on the consequences of radiation therapy, a cornerstone of cancer treatment used in approximately 50 percent of all cancer cases. Key long-term effects discussed include:
- Secondary Cancers: Radiation therapy can increase the risk of developing secondary malignancies in tissues within or near the treated area. These secondary cancers may occur years or even decades after the initial treatment.
- Cardiovascular Disease: Exposure of the heart and surrounding vessels to radiation can lead to long-term cardiovascular complications such as coronary artery disease, valvular heart disease, and pericarditis, contributing to increased morbidity and mortality in survivors.
- Pulmonary and Respiratory Effects: Radiation to the chest area can cause chronic lung damage, including fibrosis and reduced lung function, leading to long-term respiratory symptoms and decreased exercise tolerance.
- Endocrine Dysfunction: Radiation involving the brain, neck, or abdomen can affect hormone-producing glands like the thyroid, pituitary, and pancreas, resulting in hormonal imbalances and associated health problems.
- Musculoskeletal Effects: Radiation can cause fibrosis, reduced bone growth, or fractures in irradiated areas, affecting mobility and quality of life.
- Cognitive and Neurological Effects: Cranial radiation, especially in pediatric patients, may lead to cognitive impairment, memory deficits, and other neurological issues.
- Quality of Life and Psychological Health: Chronic pain, fatigue, lymphedema, and psychological distress such as anxiety or depression may persist long after treatment.
The report emphasizes the importance of long-term follow-up and monitoring of cancer survivors to manage these late effects proactively. It also highlights ongoing research to optimize radiation doses and techniques to minimize such impacts while maintaining treatment efficacy.
Newer radiotherapy treatment methods and techniques result in a different distribution of radiation to organs and tissues than older treatment regimens. Establishing a research infrastructure for the care of cancer survivors is important, focusing on modern radiotherapy methods such as tomotherapy and cyberknife, and at reduced field sizes and lower dosages.
Long-term, large-scale studies are needed to follow cancer survivors of all ages, particularly adolescents and young adults, and characterize their risks as they age. Louis S. Constine, M.D., a professor and vice-chair of the Department of Radiation Oncology at the University of Rochester Medical Center, was a member of the NCRP scientific committee and is working with others to develop a program that will provide patients with a comprehensive plan for their post-cancer care.
The report, a comprehensive, 425-page document, was published online by the Journal of the National Cancer Institute on March 6, 2012, and in hard copy on March 13. More studies are needed to analyze all aspects of the relationship between radiation dose and the risk of second malignancies and heart disease, including the development of newer risk-prediction models based on the dose absorbed by the organ and the type of radiation prescribed. Few studies have described survival after the diagnosis of second malignancies in patients who have already developed a second primary cancer.
In conclusion, the NCRP report underscores the need for continued research and monitoring to improve the quality of life and long-term health outcomes for cancer survivors.
- The NCRP report, based on extensive research and clinical follow-ups, reveals that radiation therapy, a common treatment method for over half of all cancer cases, could potentially increase the risk of developing secondary medical-conditions, like secondary cancers, years or even decades following the initial treatment.
- The report emphasizes the significance of long-term follow-up and monitoring for cancer survivors to actively manage the late effects associated with health-and-wellness issues such as cardiovascular disease, cognitive impairment, and endocrine dysfunction, among others, that result from radiation therapy.
