#343 – The evolving role of radiation: advancements in cancer treatment, emerging low-dose treatments for arthritis, tendonitis, and injuries, and addressing misconceptions | Sanjay Mehta, M.D.
Dr. Sanjay Mehta, a radiation oncologist, discusses the evolution of radiation oncology, addressing common misconceptions about radiation exposure. He delves into modern cancer treatments for breast, prostate, and brain cancers, highlighting advancements that minimize side effects. Dr. Mehta also explores the promising, yet underutilized, application of low-dose radiation for chronic inflammatory conditions and athletic injuries.
Deep Dive Analysis
14 Topic Outline
Evolution of Radiation Oncology as a Specialty
Defining Radiation: Ionizing vs. Non-Ionizing
Quantifying Radiation Doses: Gray and Sievert
Radiation Exposure from Diagnostic Imaging and Safety
Therapeutic Radiation for Breast Cancer: Evolution and Techniques
Modern Breast Cancer Radiation: Side Effects and Implants
Prostate Cancer Radiation: Patient Selection and ADT Use
Evaluating a Radiation Oncologist for Cancer Treatment
Brain Cancer Radiation: Whole Brain vs. Targeted Approaches
Historical Context and Origins of Radiophobia
Low-Dose Radiation for Inflammatory Conditions
Low-Dose Radiation for Fibrosis and Keloids
Barriers to Low-Dose Radiation Adoption in the US
Durability and Efficacy of Low-Dose Radiation Therapy
9 Key Concepts
Non-Ionizing Radiation
This refers to low-energy electromagnetic radiation, such as radio waves, microwaves, and visible light, which does not possess enough energy to eject electrons from atoms and therefore cannot damage tissue or DNA.
Ionizing Radiation
This describes high-energy electromagnetic radiation, including x-rays and ultraviolet light, which has enough energy to eject electrons from atoms, creating ions and potentially causing damage to cellular DNA.
Gray (Gy)
Gray is the SI unit for absorbed radiation dose, quantifying the amount of energy deposited per kilogram of tissue. It is primarily used in therapeutic radiation oncology to measure the dose delivered to a tumor.
Sievert (Sv)
Sievert is a unit used to measure the biological effect of radiation exposure, often in air. While technically distinct, for most practical purposes in medicine, a Sievert is considered equivalent to a Gray, though it can incorporate a quality factor for different radiation types.
Linear No Threshold (LNT) Model
The LNT model is a radiation safety principle that postulates any amount of radiation exposure, no matter how small, carries a proportional risk of causing harm. However, this model has been largely disproven for very low doses, where biological damage is negligible or even potentially beneficial.
Hormesis Effect (Radiation)
Hormesis, in the context of radiation, is a controversial concept suggesting that very low doses of radiation can stimulate beneficial biological responses, such as enhanced repair mechanisms, leading to increased resilience or even improved health outcomes.
Intensity Modulated Radiation Therapy (IMRT)
IMRT is an advanced radiation technique that uses computer-controlled linear accelerators to deliver precise radiation doses. It shapes the radiation beams with multiple small 'pixels' to conform tightly to the tumor's shape, minimizing exposure to surrounding healthy tissues.
Image Guided Radiation Therapy (IGRT)
IGRT is a technique that integrates daily imaging (like cone-beam CT or X-rays) directly into the treatment process. This allows radiation oncologists to verify and adjust the patient's position and the tumor's location daily, ensuring highly accurate and reproducible radiation delivery.
Bragg Peak
The Bragg Peak is a physical characteristic of proton therapy where the radiation dose deposition peaks sharply at a specific depth within the tissue and then rapidly drops to near zero. This allows for highly precise targeting of tumors with minimal exit dose, sparing healthy tissue beyond the tumor.
9 Questions Answered
Non-ionizing radiation, like radio waves and microwaves, has low energy and cannot damage tissue. Ionizing radiation, such as x-rays and ultraviolet light, has higher energy and can damage DNA by ejecting electrons.
Therapeutic radiation dose absorbed by tissue is measured in Gray (Gy), representing joules of energy per kilogram. General radiation exposure in the air is measured in Sieverts (Sv) or millisieverts (mSv), which are largely equivalent to Gray in terms of biological effect.
No, the radiation dose from these tests is very low (fractions of a millisievert) and the benefits of accurate diagnosis far outweigh the negligible risks. The body is more resilient to low doses than often perceived.
Modern techniques use linear accelerators and Intensity Modulated Radiation Therapy (IMRT) to precisely target the breast tissue, minimizing dose to the heart and lungs. This results in less severe skin reactions and comparable survival rates to mastectomy.
Radiation therapy for prostate cancer typically results in a lower risk of incontinence and impotence compared to surgery. Modern techniques allow for precise targeting, minimizing side effects to the bladder and rectum.
Historical radiophobia (stemming from nuclear accidents and early misuse of radiation) and turf wars with other medical specialties have hindered its adoption in the US, despite strong evidence of efficacy from European studies.
Low-dose radiation therapy can effectively treat conditions like tendinitis (e.g., Achilles, hamstring, tennis elbow), osteoarthritis, bursitis, and plantar fasciitis by providing an anti-inflammatory effect similar to cortisone but with longer-lasting results.
European studies show 60-80% success rates in reducing pain after a two-week course of treatment, with up to 90%+ success after a retreatment. Relief can be immediate for some conditions like plantar fasciitis, while others like Achilles tendinitis may take a couple of months.
Yes, low-dose radiation is effective for fibrosis, such as Dupuytren's contracture and keloids. For keloids, it must be administered adjuvantly immediately after surgical resection to prevent recurrence.
17 Actionable Insights
1. Low-Dose Radiation for Inflammatory Pain
Consider low-dose radiation (0.5 gray, three times a week for two weeks, totaling 3 gray) for chronic inflammatory conditions like tendinitis, osteoarthritis, bursitis, or plantar fasciitis, as it offers a long-lasting anti-inflammatory effect with 60-80% success and potential for retreatment after 12 weeks.
2. Radiation for Fibrotic Conditions
For Dupuytren’s contracture or Ledderhose disease, consider radiation (3 gray per fraction for five fractions, repeated after a few weeks for a total of 30 gray). For keloids, pursue adjuvant radiation (4 gray per fraction for three treatments, totaling 12 gray) immediately after surgical resection to prevent recurrence.
3. Long-Term Relief from Low-Dose Radiation
For inflammatory conditions, low-dose radiation may provide relief lasting for months to years, with some anecdotal cases reporting over a decade of relief without retreatment.
4. Advocate for Low-Dose Radiation
If suffering from chronic inflammatory or fibrotic conditions, be your own advocate and seek out radiation oncologists who offer low-dose radiation therapy, as public awareness and physician adoption are still growing.
5. Prostate Cancer Treatment Choice
When choosing prostate cancer treatment, consider radiation therapy as it offers cure rates essentially equivalent to surgery, with significant quality of life advantages such as reduced risk of incontinence and impotence.
6. Targeted Brain Metastasis Radiation
For brain metastases, advocate for stereotactic radiosurgery (SRS) to treat only the metastatic lesions, or if whole-brain radiation is necessary, inquire about Intensity Modulated Radiation Therapy (IMRT) to spare critical areas like the hippocampus and preserve cognitive function.
7. Breast Conservation Therapy
For early-stage breast cancer, consider a lumpectomy followed by radiation therapy (approximately 40 gray in 15 fractions over three weeks) as it offers comparable survival outcomes to a mastectomy with minimized heart and lung exposure.
8. Tailor Prostate ADT with Biomarkers
For Gleason 3+4 prostate cancer, utilize Decipher or Artera AI tests to stratify risk, as favorable intermediate-risk patients may potentially avoid androgen deprivation therapy (ADT) when undergoing radiation.
9. Optimize Prostate Radiation Outcomes
To minimize side effects during prostate radiation, consistently arrive with a full bladder and empty bowel, as this separates the bladder and rectum from the prostate, allowing for more precise radiation delivery.
10. Reframe Radiation Risk Perception
Understand that the Linear No Threshold (LNT) model for radiation risk has been largely disproven; at very low doses (below 50 millisieverts), there’s almost no incidence of biological damage, and a hormesis effect may even occur.
11. Prioritize Diagnostic Scans
Do not avoid necessary diagnostic procedures like dental x-rays, mammograms, or cardiac CTs, as their benefits in detecting health issues far outweigh the minimal radiation risk.
12. Leverage Hormesis for Resilience
Engage in activities that cause a small amount of cellular damage, such as low-dose radiation, cold plunges, or saunas, as the body’s repair mechanisms can make it stronger than before the exposure.
13. Select an Experienced Radiation Oncologist
When choosing a radiation oncologist, prioritize experience in your specific cancer type, interview them thoroughly, and seek a doctor who transparently discusses all potential outcomes and side effects.
14. Localized Radiation Boost for Breast Cancer
After whole breast radiation, a localized boost of an additional 10 gray (2 gray over five days) to the lumpectomy cavity can improve local control for breast cancer patients.
15. Manage Breast Radiation Skin Reaction
Expect mild redness or sunburn-like skin reactions from modern breast radiation; use normal skincare products like Aquaphor or aloe vera, as severe dermatitis is rare compared to older treatments.
16. Prophylactic Brain Radiation for Small Cell
If diagnosed with small cell lung cancer and achieving a complete response to primary treatment, discuss prophylactic cranial irradiation (PCI) (20 gray in five fractions) to significantly reduce CNS failures and improve quality of life.
17. Localized Pain Relief for Inflammatory Arthritis
For systemic inflammatory conditions like rheumatoid or gouty arthritis, low-dose radiation can effectively reduce pain in specific affected joints, though it won’t cure the underlying systemic disease.
9 Key Quotes
The higher you go in the energy and the energetics of the particles, the more likely exposure to these packets of energy are going to cause damage to your DNA.
Sanjay Mehta
The Linear No Threshold, which is Linear No Threshold, has actually been proven to be actually erroneous. And so at very low doses, it's actually been shown that there's almost no incidence of any sort of biological damage.
Sanjay Mehta
The risk-benefit ratio is so heavily in favor of doing these studies that I don't even think twice about them.
Sanjay Mehta
It's not so much the total dose, it's the dose per fraction.
Sanjay Mehta
The biggest difference between what we're doing now versus the old days wasn't so much the total dose, it was the actual homogeneity that you touched on.
Sanjay Mehta
Cure rate is key. But quality of life is equally important, if not more important for most people.
Sanjay Mehta
Radiophobia is largely a US-based phenomenon because the first cases, first of all, x-rays were discovered in 1895 by Rankin. In 1898, there was the first case described of actually radiating both arthritis-type things... and also tumors.
Sanjay Mehta
America just has to catch up.
Sanjay Mehta
I love treating cancer patients. It's really personally very rewarding to tell someone that they're NED, there's no evidence of cancer in their body anymore... But the amount of immediate relief we're seeing from all these inflammatory conditions, right away, it's a night and day.
Sanjay Mehta
3 Protocols
Breast Cancer Radiation Therapy (Modern Standard)
Sanjay Mehta- Consultation with a radiation oncologist, often prior to surgery.
- Planning procedure (simulation) 2-3 weeks post-surgery: patient is positioned (e.g., prone with arm behind head), a rigid mold (vac lock) is created, and a CT scan is performed in this position.
- Computer planning (approx. 1 week): A 3D model of the patient is used to design tangential radiation beams, precisely shaping the beam to match the chest wall curvature and minimize dose to the heart and lungs.
- Daily treatment (approx. 3 weeks): Each session takes about 15 minutes, including 5 minutes for precise patient positioning using reference marks and daily imaging (cone beam CT or PA/lateral film) overlaid with planning images, followed by 5-10 minutes for beam delivery.
- Total dose: Approximately 40 Gray (Gy) delivered in 15 fractions (around 2.5-2.6 Gy per day) to the whole breast.
- Optional boost: An additional 10 Gray (Gy) over 5 days (2 Gy per day) is given specifically to the lumpectomy cavity for improved local control, based on patient pathology.
Low-Dose Radiation for Inflammatory Conditions (German Protocol)
Sanjay Mehta- Administer 0.5 Gray (Gy) of radiation to the affected joint or area.
- Repeat treatment three times a week (e.g., Monday, Wednesday, Friday) for two consecutive weeks.
- Complete a total of 6 treatments.
- Wait 12 weeks to assess the efficacy and pain reduction.
- If needed, a retreatment course following the same protocol can be administered.
Low-Dose Radiation for Keloids (Adjuvant to Surgery)
Sanjay Mehta- Undergo surgical resection of the keloid by a dermatologist.
- Receive the first radiation treatment (4 Gy) on the *same day* as the surgery to prevent immediate fibroblast regrowth.
- Administer a total of 12 Gray (Gy) over 3 treatments (4 Gy per day).