Wednesday, April 13, 2011

More information on radiation than you should want to read.



Wow, it just keeps getting more scary in Japan.  So here's a whole range of resources for those of you who are busy watching it real time and hearing about it on the news. 

First, take a minute to check the EPA's up-to-date radiation readings for your area.  (When are they going to start adding this to the weather report?)

Then, take a few moments to read what the National Institutes of Health has to say about radiation exposure. 

If you're more of a visual person, here is a fun (in a gallows humor sort of way) way to visualize your relative exposures to radiation

As I've pointed out at alternative health answers and at my website, the ionizing radiation you receive from medical testing is likely to far outweigh your exposure from Japan. 

If we take that idea to the next level, there is a whole group that irradiates people for a living.  Radiation oncologists specialize in treating you with radiation.  They just celebrated a century of using radiation as a treatment for cancer.  If you look at the second abstract, in many cases radiation therapy is the only available treatment.  The doses being used to palliate suffering are astronomically higher than anything we see anywhere else. 

If you look at the third abstract, in cases of advanced head and neck cancer the application of radiation in huge doses directly to the area is often not sufficient to cause hypothyroidism.  We're talking about extraordinary exposure, and still the body keeps on ticking.  It's a wonderful thing. 


If you are still panting for more information on radiation,  I've attached links to three books on the subject.  Bring your medical dictionaries and dig in.  Or maybe take a walk outside and breathe easy. 

Nat Rev Cancer. 2004 Sep;4(9):737-47.



Radiation oncology: a century of achievements.

Bernier J, Hall EJ, Giaccia A.

Department of Radio-Oncology, Oncology Institute of Southern Switzerland, CH-6504 Bellinzona, Switzerland. jacques.bernier@hcuge.ch



Abstract

Over the twentieth century the discipline of radiation oncology has developed from an experimental application of X-rays to a highly sophisticated treatment of cancer. Experts from many disciplines - chiefly clinicians, physicists and biologists - have contributed to these advances. Whereas the emphasis in the past was on refining techniques to ensure the accurate delivery of radiation, the future of radiation oncology lies in exploiting the genetics or the microenvironment of the tumour to turn cancer from an acute disease to a chronic disease that can be treated effectively with radiation.

PMID: 15343280


Radiother Oncol. 2011 Mar;98(3):287-91.

Palliative radiotherapy for cervical carcinoma, a systematic review.

van Lonkhuijzen L, Thomas G.

Odette Cancer Centre, ON, Canada.

Abstract

Purpose: Worldwide, particularly in developing countries, many women present with advanced stage cervical cancer for which palliative radiotherapy is the treatment of choice or may be the only available treatment. The purpose of this study was to determine from the literature the optimal palliative radiation scheme for the treatment of advanced cervical cancer. Design: A systematic literature review up to January 2010 was performed in Medline, Embase, the Cochrane database, CinHL and Google Scholar using a combination of synonyms for: cervical cancer, palliative treatment and radiation therapy. No limitations were applied for language or study types. For included papers data were extracted and described. Results: Only eight papers were identified and none compared the results of different fractionation schemes. Most used observational retrospective study design with considerable sources of bias. No studies used validated endpoints for symptom relief nor did they include measures of the quality of life. Several papers described the experience with single or multiple monthly 10Gy doses or with a higher total dose delivered in 2-4 fractions within 48h to 1week. Studies report varying amounts of relief from bleeding. The effect on other symptoms such as pain and discharge is not evaluable. Acute and late toxicity is poorly documented. Conclusion: There is a dearth of information in the current literature to guide selection of an optimal palliative radiation schedule for treatment of patients with advanced cervical cancer. Based on this review and information from other solid tumors, there is no evidence to support the common belief that better and longer palliation is achieved with a high dose delivered in multiple smaller fractions. There is a clear need for comparative studies of different radiation fractionation schedules in order to identify an optimal palliative radiation scheme. These studies require the use of validated endpoints to measure specific symptom relief as well as accompanying quality of life.

Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

PMID: 21316785

Radiother Oncol. 2011 Apr 1. [Epub ahead of print]

Radiation-induced hypothyroidism in head and neck cancer patients: A systematic review.

Boomsma MJ, Bijl HP, Langendijk JA.

Department of Radiation Oncology, University Medical Center Groningen, The Netherlands.

Abstract

PURPOSE: To review literature on the relationship between the dose distribution in the thyroid gland and the incidence of radiation-induced hypothyroidism in adults.

MATERIAL AND METHODS: Articles were identified through a search in MEDLINE, EMBASE and the Cochrane Library. Approximately 2449 articles were screened and selected by inclusion- and exclusion criteria. Eventually, there were five papers that fulfilled the eligibility criteria to be included in this review.

RESULTS: The sample sizes of the reviewed studies vary from 57 to 390 patients. The incidence of hypothyroidism was much higher (23-53%) than would be expected in a non-irradiated cohort. There was a large heterogeneity between the studies regarding study design, estimation of the dose to the thyroid gland and definition of endpoints. In general, the relationship between thyroid gland volume absorbing 10-70Gy (V10-V70), mean dose (Dmean), minimal dose (Dmin), maximum dose (Dmax) and point doses with hypothyroidism were analysed. An association between dose-volume parameters and hypothyroidism was found in two studies.

CONCLUSIONS: Hypothyroidism is frequently observed after radiation. Although the results suggest that higher radiation doses to the thyroid gland are associated with hypothyroidism, it was not possible to define a clear threshold radiation dose for the thyroid gland.

Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

PMID: 21459468



 

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