dr. alberto lachos davila · radioterapia 1895 ... (vmat/rapidarc/tomotherapy) robotic mounted...
TRANSCRIPT
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DR. ALBERTO LACHOS DAVILA Médico Asistente Departamento de Radioterapia
INSTITUTO NACIONAL DE ENFERMEDADES NEOPLASICAS
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TECNOLOGÍA EN LA MEDICINA
1895 W. C. Roenteng descubre los rayos X.
1921 por primera vez se utiliza un microscopio en una operación; actualmente en vez de microscopios, se utiliza la técnica “endoscopia” para realizar cualquier intervención quirúrgica demasiado pequeña para la vista humana.
1942 se utiliza por primera vez un riñón artificial para la diálisis; este sistema de órganos artificiales se ha desarrollado significativamente por todo el mundo.
1952 P.M. Zoll implanta el primer marcapasos; son dispositivos eléctricos que hacen latir el corazón descargando impulsos eléctricos, que reemplazan el propio sistema de control del corazón.
1953 se obtiene el modelo de la doble hélice del ADN; se puede señalar que este descubrimiento revolucionó tanto la medicina como nuestra manera de pensar. En el año de 1991 se inició un programa, Análisis del Genoma Humano, que tiene como principal objetivo descifrar el código genético humano. Hasta la fecha se han identificado cerca de 18,000 genes. En un futuro, gracias a las nuevas computadoras, cada vez más especializadas, se identificará un gen cada hora.
1967 primer trasplante de corazón entre humanos. Hoy en día, estos trasplantes, gracias a la aplicación de la tecnología, es una operación relativamente sencilla.
1980 Scanner TAC (Tomografía Axial Computarizada) :No hay duda que las técnicas desarrolladas alrededor de la TAC han revolucionado la forma de diagnóstico de muchas enfermedades y sobre todo de lesiones en tejidos blandos. No se podría imaginar tener en la actualidad un hospital sin éste tipo de equipos
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HISTORIA DE LA
RADIOTERAPIA
1895 Descubrimiento de los rayos X
1896 Descubrimiento de la Radioactividad
1898 Descubrimiento del Radium
1920’s mejoras en los tubos de RX (150-300Kv)
1950’s Cobaltos (1Mv or million volt)
1960’s Acelerador Lineal (4 - 25 million)
1970’s computadoras y TAC
1980’s Radioterapia 3D
1990’s Radioterapia conformada 3D
2002 IMRT
2002+ IGRT
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3 DCRT
Radiation Therapy
Teletherapy
Brachytherapy
IMRT
IGRT DART
Electronic Brachytherapy
Tomotherapy
Image Assisted Brachytherpy
Stereotactic radiotherapy
Gamma Knife
LINAC based
Cyberknife
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Use alternative radiation modalities
Electrons
Protons
Neutrons
π- Mesons
Heavy Charged Nuclei
Antiprotons
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NUEVA VISION EN MEDICINA
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bladder
Radiation zone
prostate
rectum
OBJETIVO = OCUPAR EL VOLUMEN
BLANCON CON PEQUEÑOS MARGENES
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Radioterapia conformada
en 3D
Estudio randomizado en el MD Anderson
conventional 53%
conformal 72%
Pollack IRJOBP 1996;34:555
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FDA Approval 4.29.10
median OS of 25.8 months compared to 21.7
months for patients who received the control
treatment There was no difference in time-to-
progression.
The total cost for three courses of treatment
with Sipuleucel-T is $93,297.60
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Recurrencia en Cáncer de Próstata y
dosis de radiación
< 72Gy
72 - 82Gy
82Gy
Kupelian. IJROBP 2008:71:16
años
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Existe movimiento significativo de la
próstata por el gas rectal
Planned
target
Rectal gas
No Rectal
gas
Planned target,
missed badly if
rectal gas pushes
the prostate
forward
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IGRT comparado a IMRT en cáncer de
próstata
riesgo intermedio alto riesgo
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Bajo riesgo de efectos secundarios con IGRT
comparado a IMRT
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Combine a CT scan and linear accelerator to ultimate in
targeting (IGRT) and ultimate in delivery (dynamic, helical
IMRT) ability to daily adjust the beam (ART or adaptive
radiotherapy)
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Cyberknife
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TASAS DE CURACION EN CANCER DE
PROSTATA CON CYBERKNIFE
N = 515, Alan Katz in New York
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SBRT EN CÁNCER DE PROSTATA / Naples-
Tampa
Feb 2005 – Apr 2008 (Naples, FL)
• 164 monotherapy, 35 Gy
• 168 monotherapy, 36.25 Gy
• 59 EBRT + CK boost
Jul 2008 – Dec 2011 (Tampa, FL)
• 121 monotherapy, 36.25 Gy
• 10 monotherapy, 38 GY
• 12 EBRT + CK boost
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IMRT Vs BRAQUITERAPIA
I M R T BRACHYTHERAPY
PTV
RECTUM
BLADDER
RECTUM
BLADDER
PTV
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1990 1995 2000 2005 0
500
1000
1500
2000
2500
Número de publicaciones en Google Scholar
3 DCRT IMRT IGRT
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Treatment Median Survival Local Failure
Whole brain external 8 – 15 w 52%
surgical resection 33 – 38 w 20%
rasdiosurgery 44 w 14%
METASTASIS
CEREBRAL
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METASTASIS CEREBRAL
RADIOTERAPIA EXTERNA
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METASTASIS
CEREBRAL
RADIOCIRUGIA
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RADIOCIRUGIA DE CUERPO
VERTEBRAL
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TUMORES DE CABEZA Y
CUELLO.
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Mejora de la sobrevida en Cáncer de
Cabeza y cuello con IMRT
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TUMORES DE CABEZA Y CUELLO.
Función salival y Xerostomia.
Prince of Wales Hospital; 2007 (Hong Kong)(2001-2003) -- "Prospective randomized study
of IMRT on salivary gland function in early-stage nasopharyngeal carcinoma patients."
(Kam MK, J Clin Oncol. 2007 Nov 1;25(31):4873-9.)
Randomized. 60 patients with T1-2bN0-1 nasopharynx.
Arm 1) IMRT 66 Gy (CTV=GTV + 1cm; at-risk anatomic sites; LN Levels IB-II, LN upper
Level V, LN retropharyngeal; PTV=CTV+3mm), lower neck LN+ 66 Gy anterior field, LN-
54-60 Gy + intracavitary BT boost VS Arm 2) 66 Gy 2D + intracavitary BT boost
Outcome: observer-related severe xerostomia IMRT 39% vs. 2D-RT 82%,
but no difference in patient-reported feeling of xerostomia
Conclusion: IMRT superior in preserving objective parotid function, but no
difference in patient-reported benefit
Editorial : Observer-rated scoring underestimates patient reports and has low agreement among
various observers. Suspect sparing of parotid alone not sufficient. Parotid gland produces saliva without
mucins (lubricants, bind water, and provide selective permeability barrier). Mucin-secreting glands (e.g.
minor salivary glands, submandibular glands) produce <10% saliva but >50% mucins. May need to
spare these glands as well for subjective feeling of benefit
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Grills, Mangona, et al William Beaumont Hospital, Detroit
JCO Feb 2010
First published direct comparison of SBRT to any form
of surgery for stage I NSCLC
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Irradiación localizada de
SBRT
Multiple non-coplanar fixed fields
Arcing IMRT (VMAT/RapidArc/Tomotherapy)
Robotic Mounted Linac (cyberknife)
High precision localised radiotherapy for NSCLC
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Optimización de la
radioterapia
Stage III NSCLC: ChemoChemo/RT (200 patients randomized)
2 yr LF 1yr OS 2 yr OS 3 yr OS
ENI 49 59.7 25.6 19.2
IFRT 41 67.2 38.7 27.3
P = 0.048
Tumor
50Gy
60-64Gy
Tumor
50Gy
68-74Gy
STDF IF
Yuan , ASCO 2006, Abstract # 7044
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5
7
9
11
13
15
17
19
21
23
25
27
29
31
1980's 1990's 2000's 2010's
me
dia
n s
urv
iva
l
CALBG
Finsih
IGR
NCCTG
WJLCG
GLOT
CZECH
LAMP
RTOG 9410
MUNICH
ECOG 2597
HDChemo/RT
HD Biological/RT
HD/Chemo/Biol/RT
MEJORAS EN LA SOBREVIDA EN CANCER EN CANCER DE PULMON 1980–2010
?
+PCI
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Delineación del blanco
34 pacientes
17 componente atelectásico
9 cambios en los campos
con FDG
6 disminuyó el campo
17 Sin atelectasias
(3 sufrieron cambios)
Nestle U et al. Int J Radiat Oncol Biol Phys 1999; 44:593-7
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Int. J. Radiation Oncology Biol. Phys., Vol. 69, No. 4, pp. 1282–1289, 2007
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ANTICUERPO MONOCLONAL RADIO-
ACTIVO
monoclonal antibody targets the CD20 antigen, which is found on the surface of B-cell tumors
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Radio-active Monoclonal
Antibodies
In February 2002, Zevalin was the first radioimmunotherapy to
receive FDA approval. Zevalin consists of a monoclonal antibody
linked to the radioactive isotope yttrium-90. After infusion into a
patient, the monoclonal antibody targets the CD20 antigen, which
is found on the surface of B-cell tumors. In this manner, cytotoxic
radiation is delivered directly to malignant cells.
On June 30, 2003 announced FDA approval of BEXXAR
(Tositumomab and Iodine I 131 Tositumomab)