Radiation Oncology at the Border: Dónde Estamos? Border Health Viscount Suites Hotel 10/28/05, Tucson AZ Lars Ewell, PhD Assistant Professor, Department of Radiation Oncology, University of Arizona College of Medicine firstname.lastname@example.org
2 Radiation Oncology at the Border: Dondé Estamos? • Introduction • Radiation Oncology • Radiation Oncology en Los Estados Unidos • Radiation Oncology en Mexico • Equipment Costs • Accidents • Future in Both Countries • Conclusion
3 Introduction • Goal of radiation therapy is to kill cancerous cells, while sparing normal tissue. • Radiation therapy can be either curative, or palliative. • In contrast to diagnostic procedures, therapeutic doses are high. 5000 cGy vs 10 cGy (CAT scan).
4 Radiation Oncology en Los Estados Unidos • In the US in 1995, 41% of the 1,252,050 newly diagnosed cases of cancer were treated with radiation. • These radiation treatments relieved suffering and extended the lives of the patients being treated. • Along with early diagnosis, radiation treatments contributed to a 1.1% decrease in annual cancer death rates from 1993 through 20021. 1) Edwards et al., Journal of the National Cancer Institute, Vol. 97, No. 19, 1407-1427, October 5, 2005
5 Radiation Oncology en Los Estados Unidos 2 2) Radiation in Medicine - A Need for Regulatory Reform, K. Gottfried and G Penn editors, National Academy Press, Washington DC, 1996.
6 Radiation Oncology en Los Estados Unidos 2
7 Radiation Oncology en la Universidad de Arizona Hospital • http://www.rad-onc.arizona.edu/ • ~ 60 Patients Cada Dia • 5 Attending Physicians, 5 Residents • 3 (4) Physicists (Físicos Médicos) • Dosimetrists, Therapists, Nurses, Administrators • 3 machines: Elekta SLi, Siemens S2 and Novalis Brainlab • Brachytherapy: Permanent Prostate Seed, Eye Plaque (ocular melanoma), High Dose Radiotherapy (HDR) • Pinnacle Treatment Planning System • Marconi 5,000 CAT Scan
8 Radiation Oncology en Los Estados Unidos: Agencies/Regulations • Nuclear Regulatory Commission (NRC): Regulates reactor produced radio-nuclides used in radiotherapy. • American Board of Radiology (ABR): Provides board certification for physicians and physicists. • Radiological Physics Center (RPC): Provides quality assurance for radiotherapy physics equipment.
9 Radiation Oncology en Mexico • Comisión Nacional de Seguridad Nuclear y Salvaguardias (CNSNS): Provides for regulation of radiotherapy in Mexico (see http://www.cnsns.gob.mx/index.htm ). • Currently, there are 83 facilities licensed by the CNSNS to perform radiotherapy. • Closest is perhaps in Hermosillo (none in Nogales).
10 Radiation Oncology en Mexico • United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report, Appendix D: Medical Radiation Exposure (year 2000). • Four different categories for countries depending on how many physicians per population. • Mexico – II: < Mexico <
11 Radiation Oncology en Mexico • Diagnostic Equipment: • 1996, US: 6,800 CAT scanners, 3,500 MRI scanners. • 1996, Mexico: 56 CAT scanners, 2 MRI scanners. • Radiotherapy Equipment: • 1996, US: 1,893 Linear Accelerators, 504 Co. • 1996, Mexico: 24 Linear Accelerators, 92 Co.
12 Radiation Oncology en Hospital Oncológico del Estado de Sonora en Hermosillo 2004 • 2 radio-oncológos, 3 físicos médicos, 6 técnicos en radioterapia, 1 ingeniero en electrónica • 2 machines: GE Saturno 41 y Cobalto 60 Theratronics • GE VERASIM II Simulator (diagnostic) • Braquiterapia: HDR with GammaMed plus
127 Tumor Maligno de la Mama 106 Tumor Maligno del Cuello del Útero 48 Tumor Maligno de Bronquios y Pulmón 30 Tumor Maligno del Sistema Nerviso Central y Medula Espinal 29 Tumor Maligno de Prostata 13 Radiation Oncology en Hospital Oncológico del Estado de Sonora en Hermosillo 2004: Treatment
New Varian Clinac 600C: Single 6MV photon energy, no electrons, no MLC - $USD 650,000 New Varian Trilogy: Two photon energies, electrons, MLC (IMRT), OBI - $USD 3,500,000 New MDS Nordion 60Co basic: 1MV photon energy, no MLC - $USD 400,000 New MDS Nordion 60Co Equinox: 1MV photon energy, MLC - $USD 900,000 14 Radiation Oncology: New Equipment Costs
Varian 600C: Single 6MV photon energy, no MLC - $USD 175,000 Varian 2100C: Two photon energies, electrons - $USD 250,000 CT Scanners: From $USD 75,000 to $500,000+ for multislice systems 15 Radiation Oncology: Used Equipment Costs
16 Radiation Oncology: Accidents • In April, 2005, it was discovered that 77 patients that had been treated for brain tumors at the H. Lee Moffitt Cancer & Research Institute in Tampa Florida had received ~50% overdose of radiation3. • A physicist had miscalibrated the machine and this resulted in the overdose. • Error was caught when the RPC conducted a routine calibration check of the Novalis Brainlab linear accelerator. 3) Hemingway-Johnson, ‘Patients Given Too Much Radiation’, Tampa Tribune, April 2, 2005 .
17 Radiation Oncology: Accidents • In early 2001, it was discovered that a number of patients treated in Panama had been given excessive radiation4. • The Treatment Planning System (TPS), RTP/2 Multidata System Version 2.11, used to calculate the amount of radiation to deliver had a bug in it. • Depending on the direction (clockwise or counterclockwise) of contour drawn, the TPS would either account for the block, or not. • Error discovered when radiation oncologists noticed an excessive number of cases of diarrhea. 4) ‘Investigation of an Accidental Exposure of Radiotherapy Patients in Panama’, IAEA, August 2001 .
18 Radiation Oncology: Future • Intensity Modulated Radiation Therapy (IMRT) • Image Guided Radiation Therapy (IGRT) • Adaptive Therapy • En Mexico, Mas CAT Scans, Mas MRI scans
19 Conclusion • By studying border health, there is much to be learned in the field of Radiation Oncology. • This will continue to be an important area of study in the years to come. • There are substantial benefits to be gained, both north and south of the border.
20 Acknowledgment • Dr. Jose Benjamin Arroyo Acosta • Angela Enciso, Drs. Tom Cetas, Chris Watchman • Carlos Caballero