Tuesday, March 3, 2009

History of Cervical Cancer Treatment

Dr. Montana presents on the history of cervical cancer treatment.

1895 Roentgen discovers x-rays
1896 Becquerel discovers natural radiation
1898 Polonium and Radium discovered by Marie and Pierre Curie
Polonium is named after Marie's native Poland.
1934 Discovery of artificial or induced radioactivity Irene and Frederic Joliot-Curie

1903 intracavitary brachytherapy was first used for treatment of a gynecologic cancer - Margaret Cleaves
1903 Alexander Graham Bell proposes interstitial brachytherapy as a treatment for neoplasm

Aspects of Cervical Cancer which make it ideal for brachytherapy : Accessibility, Radiosensitive, Tolerance of normal tissues, and an Orderly pattern of Spread.

Competing systems of Brachytherapy.
Paris  - tandem of rubber, colpostats fabricated of cork with paraffin coating.  tandem loading 6.66 13.33 13.33, colpostats 13.33 and 13.33.  120 hour insertion - dose was 7200 mg*hrs.

Stockholm - metal tandem and colpostats.  tandem as ~40mg, vaginal plaque was loaded at 70mg.  Applications of 20-30hrs of 3 applications over 3 weeks.  6844 - 7266 mg*hrs.

Manchester - rubber tandem and ovoids.  units of radium 1unit=5mg radium.  tandem was 2-2-1, ovoids 3-5 depending on size.  7200 r were prescibed to point A (2cm superior to the flange or top of the ovoids, along the axis of tandem, 2cm laterally to the axis of the tandem).  Packing was used to distance critical normal tissues. 

Significant cure rates began occuring in the late 1910s to mid 1920s.  By the 1940s 5 year OS was ~35%.

MD Anderson - Fletcher grew up in France - initially came to Memorial for practice, and gathered experience at Stockholm and Manchester system.  Developed the a preloaded applicator, which forms the basis of our current system.  Fletcher was a big proponent of the mg*hrs system, though point A began to dominate Rx points.   Loading was 1.2 to 1 ratio of uterine to vaginal cavity activity.  Introduced vaginal mucosa, bladder, and rectal dose tolerance.  Also tailored mg*hours in combination with EBRT to stage of disease.

Herman Suit - Introduced afterloaded applicator to reduce exposure to physicians. 

1963 - afterloading brachytherapy
1974 - HDR brachytherapy
1976 - afterloading transperineal
1977 - 3D treatment planning
1996 - IMRT 

Future Directions should be geared towards reducing cost of current state of the art treatments (vaccines - concurrent chemotherapy) so that these innovations can be disseminated to the developing world. 

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