What should you take away from this presentation?

Transcription

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2 What should you take away from this presentation? A better understanding of how treatment machines can affect: Cancer Care Facility Radiation Therapists Radiation Oncologists Medical Physicists Dosimetrists Patient Satisfaction

3 Wilhelm Conrad Roentgen German Physicist HISTORICAL MILESTONES

4 Discovery of X-rays in 1895

5 The Advent of Radiation Therapy Machines

6 Legacy Hospital Portland, Oregon Cobalt 60

7 OHSU s 1st Radiation Therapy Machine Commissioned in 1953

8 VanDe Graff Machine

9 Peacock System on Linac 6100

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11 OHSU s Latest Treatment Modalities Varian Trilogy Tomotherapy Varian/Novalis Brain Lab Exactrac Calypso Philips CT SIM Brachytherapy HDR Eye plaques Intrabeam Hyperthermia 11

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13 Photon Energies 6 MV 23 MV Electron Energies 6 MeV 9 MeV 12 MeV 16 MeV 20 MeV

14 CBCT (Cone Beam Computed Tomography)

15 Imaging kv/kv

16 Imaging MV

17 Common Treatments Used For This Machine Prostate Breast Lung Heterotopic Ossification Whole Brain Sarcoma Multiple Myeloma Total Body Irradiation Bone Marrow Transplant Total Skin Irradiation Mycosis Fungoides Anal Rectal Lymphoma Head & Neck Cranial Spinal

18 Table and Field Limits Table Limit: 440 lbs Field Limit: 40cm x 40cm 120 MLC leafs 80 leafs are 0.5 cm 40 leafs are 1 cm

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20 TomoTherapy Energy 6 MV No electron capabilities

21 TomoTherapy Imaging - MVCT

22 Table Limits: 440 lbs

23 Field Limits Longitudinal: Controlled by Jaws 5cm, 2.5cm, and 1cm Maximum Longitudinal treatment field 145 cm Ant/Post and Left/Right Limited by the Field Of View FOV is 40 cm across

24 Leaf Thickness Leaf Thickness 10 cm Leaf Width cm Number of Leafs 64 cm

25 Tomo MLC Shapes

26 Tomo Beam

27 Common Treatments H&N Cancers Pancreas Liver Esophagus Rectal CranioSpinal H-N Pancreas Craniospinal Re-Irradiation

28 NovaLis ExacTrac

29 Energies Novalis 6 MV 10 MV Electron Capable Weight Limit 315 lbs

30 MLC Field Limits ¼ cm leafs ½ cm leafs Field dimensions 22 wide by 32 long 30

31 ExacTrac Imaging

32 Common Treatments SBRT Lung Liver/Pancreas/Gallbladder SRS/SRT Pediatric Tumors GBM 32

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34 Varian Trilogy Tomo Therapy

35 Case Description 4 year old male PNET (Primitive Neuro Ectodermal Tumour) Underwent gross total resection Dose 36 Gy to the craniospinal axis Posterior Fossa Boost 55.8 Gy

36 Set Up Considerations Tomo: Patient Supine on VacLoc. VacLoc pushed up to U-Frame with A headrest Varian: Patient Supine on VacLoc VacLoc pushed up to U-Frame with A headrest

37 Tomo (MVCT) Comparing Tomo vs. Varian IMAGING PROCEDURES Time: 15 to 25 min Scan 4cm at L-Spine Make shifts to patient, not table Write down table corrections Scan 4cm at T-Spine Write down table corrections Scan 4cm at C-Spine Write down table corrections Scan from mid-skull to mid C-spine Compare table corrections

38 Comparing Tomo vs. Varian IMAGING PROCEDURES Varian Day 1 9 to 12 images- one for each field 3 Right Lateral MV Portals 3 Left Lateral MV Portals 3 Posterior/Anterior MV Portals» 3 more if the spine field is long Time 25 to 35 min Once a week Lat and AP MV Portal Time 4 to 7 min

39 Treatment Considerations Tomo After imaging and shifts Watch patient for movement Varian After imaging and shifts Watch patient for movement Table kicks (Yaw) Field matching Feathering

40 TomoTherapy Plan Energy 6MV Duration 9 min 1.3 sec Gantry Rotations 19 Couch Travel (Y-axis) 61.5 cm

41 Varian Trilogy Plan Energy 6MV PA Spine Field SSD: 100 Y2: 18, 17.5, 17 cm Rt Lat Brain Field Gantry: 270 Collimator: 10 Couch Rotation: 8 Y1: 12.6, 13.1, 13.6 cm Lt Lat Brain Field Gantry: 90 Collimator: 350 Couch: 352 Y1: 12.6,13.1, 13.6

42 What Modality Was Selected And Why The homogeneity of the dose was improved with the TomoTherapy plan The Tomo plan was able to decrease Dose to the Brain Stem Spinal Cord Heart Right and Left Cochlea Pituitary Exit doses of all other organs All vertebral bodies received a dose of 15 Gy Will allow consistent growth across the volume of the patient s vertebral body

43 Dose Volume Histogram Brain Stem Tomo Max Dose 38.5 Gy Varian Max Dose 39.4 Gy

44 Dose Volume Histogram Spinal Cord Tomo Max Dose 37.9 Gy Varian Max Dose 42.2 Gy

45 Dose Volume Histogram Rt Cochlea Tomo Mean Dose 23.7 Gy Varian Mean Dose 38.2 Gy Lt Cochlea Tomo Mean Dose 24.6 Gy Varian Mean Dose 38.3 Gy

46 Dose Volume Histogram Heart Tomo Mean Dose 2 Gy Varian Mean Dose 25.2 Gy

47 Dose Volume Histogram Pituitary Tomo Mean Dose 37.6 Gy Varian Mean Dose 37.9 Gy

48 Side Effects Acute Fatigue Skin erythema Taste changes Hair loss Nausea Vomiting Loss of appetite Weight loss Low blood counts Chronic Brain injury Patient had learning disabilities from birth and after resection surgery Hearing loss Possible radiation necrosis in cerebellar peduncle

49 Patient Outcome 6 months after Radiation treatment Increased Appetite Improved memory Improved muscle strength Truncal weakness Tumor enhancement found on MRI 7 months after treatment

50 Patient Satisfaction Patient, though young, was not afraid of the TomoTherapy Unit Patient s parents were concerned and intimidated at first They felt comfortable after explanation of TomoTherapy

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52 Case Description 78 year old woman Unresectable adenocarcinoma of the pancreatic head 2.3 x 2.2 cm with involvement of the hepatic arteries and SMA T4N1 RT w/ concurrent Xeloda Dose: 45Gy Gy Boost to 59.4 Gy (33 fractions) Fiducial marker placement to assist in imaging Followed up by Gemcitabine

53 Set Up Considerations TomoTherapy Supine VacLoc Wing Board Knee Sponge Bilateral Levelers and SCI Varian Trilogy Supine VacLoc Wing Board Knee Sponge Bilateral Levelers and SCI

54 Comparing Tomo vs. Varian IMAGING PROCEDURES Tomo (MVCT) Scan 15 to 25 slices 6 mm each slice Time 2 to 3 minutes

55 Comparing Tomo vs. Varian IMAGING PROCEDURES Varian Cone Beam Time ExacTrac 2 ½ to 3 ½ min 1 min

56 TomoTherapy Plan Energy 6MV Duration 2 min 40 sec Gantry Rotations 14 Couch Travel (Y-axis) 8.19 cm

57 Varian Trilogy Plan Energy 10 MV ARC Field 1 Clockwise Gantry: deg Collimator: 10 deg MU: 179 ARC Field 2 Counter Clockwise Gantry: deg Collimator: 350 deg MU:224

58 What Modality Was Selected And Why Both plans were nearly the same Tomo gave less dose to the spinal cord The implanted gold markers were not visualized well on the TomoTherapy unit Moved to the Varian Trilogy after 540 cgy

59 Dose Volume Histogram Spinal Cord Tomo Max Dose 73.6 Gy Varian Max Dose 76.3 Gy

60 Dose Volume Histogram Liver Tomo Max Dose 45.4Gy Varian Max Dose 45.3 Gy

61 Dose Volume Histogram Rt Kidney Tomo Max Dose 37.2 Gy Varian Max Dose 37.3 Gy

62 Dose Volume Histogram Lt Kidney Tomo Max Dose 20.5 Gy Varian Max Dose 14.1 Gy

63 Tomo vs. Varian IMAGING COMPARISONS MVCT (Tomo) CBCT (Varian)

66 Fatigue Abdominal pain Slight weight loss Slight Appetite loss Back Pain Nausea Was under control by end of treatment Dry mouth Side effects

67 Patient Recovery Fatigue began to decrease a week or two after treatment finished Appetite increased Back pain did not subside Patient was found to have systemic disease 2 months after treatment

68 Patient Satisfaction Patient felt intimidated by the machine Overly complicated treatment Fear of the unknown was a factor at first

69 Varian Trilogy TomoTherapy

70 Case Description 60 year old Male T3N2bM0 squamous cell carcinoma of the right tonsil P16 positive tumor treated with chemoradiotherapy Cisplatin (3 Cycles) Dose 70 Gy (35 fractions)

71 Tomo Set Up Considerations Aquaplast mask with B headrest on Halycon board Varian Aquaplast mask with B headrest on Halycon board

72 Comparing Tomo vs. Varian IMAGING PROCEDURES Tomo (MVCT) Scan 20 to 30 slices 4 mm each slice Time 3 to 4 minutes

73 Comparing Tomo vs. Varian IMAGING PROCEDURES Varian CBCT (Cone Beam) Time 2 to 3 minutes

74 Tomo vs. Varian IMAGING QUALITY MVCT (Tomo) CBCT (Varian)

77 Treatment Considerations Tomo After imaging and shifts Watch patient for movement Varian After Imaging and shifts Watch patient for movement during Arcs Some treatments involve table kicks (Yaw adjustments)

78 TomoTherapy Plan Energy 6MV Duration 5 min 44 sec Gantry Rotations 28.6 Couch Travel (Y-axis) 20.5 cm

79 Varian Trilogy Plan ARC Field 1 Counter Clockwise Gantry: deg Collimator: 10 deg MU: 258 Energy 6MV ARC Field 2 Clockwise Gantry: deg Collimator: 350 deg MU: 252 ARC Field 3 Counter Clockwise Gantry: deg Collimator: 5 deg MU:103

80 What Modality Was Selected And Why Varian decreased dose to: Spinal Cord Left Parotid Right & Left Cochlea Tomo decreased dose to: Mandible Hyoid Right Parotid

81 Dose Volume Histogram Rt Cochlea Tomo Mean Dose 6.2 Gy Varian Mean Dose 4.8 Gy Lt Cochlea Tomo Mean Dose 6.6 Gy Varian Mean Dose 3.9 Gy

82 Dose Volume Histogram Spinal Cord Tomo Max Dose Gy Varian Max Dose Gy

83 Dose Volume Histogram Rt Parotid Tomo Mean Dose 30.3 Gy Varian Mean Dose 31.7 Gy Lt Parotid Tomo Mean Dose 28.4 Gy Varian Mean Dose 28.1 Gy

84 Dose Volume Histogram Mandible Tomo Max Dose 73.6 Gy Varian Max Dose 76.3 Gy

85 Dose Volume Histogram Hyoid Tomo Max Dose 72.5 Gy Varian Max Dose 76.3 Gy

86 Side Effects Last week of treatment: Mucositis Weight loss Brisk Erythema Extremely tired Sore throat Not eating much Drinking a bit

87 Side Effects/Recovery 3 months after treatment Sore tongue Small amount of bone exposure on the left lingual surface of mandible No thrush, No mucositis Tonsils looked good Edema of the epiglottis and the arytenoids True cords looked good and moved freely Weight loss

88 Side Effects/Recovery One year out from treatment: Eating well Swallowing fairly well Had dry mouth No sore throat No ear pain No cough He is very active in delivering phone books

89 Patient Satisfaction Claustrophobic Had trouble with the mask and being in the bore the first 3 days Near the end of treatment patient felt treatment was almost not worth the effort 3 months/6 months/1 year later patient was very satisfied with the experience as a whole

90 How does it affect your facility s workflow?

91 OPINIONS

92 Opinions of Radiation Therapist (22) TomoTherapy Fear of losing patient set-up skills MVCT for every patient can add up Time Dose Boring Nothing to do while patient is being treated but watch the patient for movement NEGATIVE Uncomfortable not being able to see the movement of the gantry and MLC s If plan is changed tomo does not update the remaining fractions Takes time for patient to come out of bore in case of emergency The image quality could be better It would be nice if kv imaging were available Varian Trilogy Needs a button that automatically takes the gantry and collimator to the zero position The image quality of the Port Films are not very good Clearance issues with the electron cone at 100 SSD Software crashes too often Can take up to 10 minutes to correct

93 Opinions of Radiation Therapist POSITIVES TomoTherapy Extremely easy to operate compared to other machines Better treatment capabilities for pediatrics Dose is tracked by time and MUs Same amount of time for every fraction Can choose to avoid areas when doing a scan Varian Trilogy Can see patient with few obstructions Can see movement of gantry, colli, and MLC s during treatment Standard workhorse with solid imaging basics

94 Opinions of Dosimetrists (5) TomoTherapy Can not do adaptive planning as well as the Varian Trilogy Can not treat overly wide treatment fields When planning Have to consider images quality of MVCT Can not see TACE or gold seeds NEGATIVES Varian Trilogy Patients can be accessed by multiple users Plans can be altered by other user when saved without your knowledge

95 Opinions of Dosimetrists POSITIVES TomoTherapy Excellent with long treatment fields Works well for midline structures ie. Liver, Spine, Varian Can treat a wider scope of diseases Planning system is user friendly i.e. Eclipse s has a better resolution when contouring Can create plans using automatic computer interpolation

96 Opinions of Radiation Oncologists (5) NEGATIVES TomoTherapy Seem to have side effects with prone anal plans Length of the treatment times MVCTs are harder to read for image guidance Varian Trilogy Can not adjust for roll Does not treat long fields uniformly

97 Opinions of Radiation Oncologists TomoTherapy Better at concave structures Ie: head and neck Fewer setup variables on a day to day basis Fewer opportunities for errors ie. Wedges, gantry angle, table angle Plans look better than Varian on large treatment volumes MVCTs are good for pts with hardware after surgery TOMO can adjust for roll POSITIVES Varian Trilogy Varian can do almost any treatment Can adjust for Yaw Easier for creating plans

98 Opinions of Physicists (6) NEGATIVES TomoTherapy QA s take longer Not able to use the same Isocenter for every patient s QA Have to go back into the room and reset for each patient s QA No clear separation for service mode Needs dose technique options for MVCT Adjust for scanning different body thickness Drawing tools for structures are bad Software support for film and water scanner could be improved Image quality could be better Adaptive planning too complex Software tries to do too much Weekly chart checks have to be manually put into ARIA Corrected if have latest software version of Aria and Tomo Varian Trilogy CBCT s algorithm can be 10% or more off Can not use image for planning Very difficult for commissioning All the systems have to be integrated IMRT (Rapid Arc) is not as good as TomoTherapy Better if it could handle more data Then able to do more than 3 Arcs There is more beam modulation with its step and shoot than its Arcs Limited to about 9 fields» Leakage/Time Can t handle the same amount of modulation Only good enough for prostate

99 Opinions of Physicists TomoTherapy Inverse planning easier than other s MVCT superior to CBCT Can be used for planning High degree of beam modulation Can manipulate beam more POSITIVES Varian Trilogy Easy well established QA system Planning tools are very user friendly Can treat nearly any type of cancer efficiently

100 Opinions of Patients TomoTherapy Tomo bore can cause some claustrophobia Tomo can be loud Because of the cooling fans and leaf movement Varian Trilogy Gantry head is intimidating Creaking noise of gantry Worry it will fall

101 Conclusion Both the TomoTherapy and Varian Trilogy machines have their positives and negatives The biggest complaints with the TomoTherapy: Poor imaging Lack of flexibility with the software The biggest complaints with the Varian Trilogy: Glitches in the software Causing down time Inability to treat long fields Without feathering or matching The most mentioned positives about TomoTherapy: Not having to worry about the gantry and table position during treatment Ability to treat long fields The most mentioned positives about the Varian Trilogy: It can handle almost any type of treatment You can see the actual field on the patient

102 Bibliography IMAGES Thank you to 1. Varian 2. Novalis 3. Accuray (Kelly McDonald) 4. Coworkers 5. Chief therapist 6. Onocologists 7. Physists 8. Dosimitrists

103 Contact Info