2d and 3d planning in lung
TRANSCRIPT
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Planning Meet
2D and 3D Planning in Lung
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Lung Cancer
Most commonly diagnosed cancer world wide.Also leading cause of cancer related deaths.
Treatment depends upon Type, Stage of the
disease & GC of patient.
50 60% pts. Require RT at least once while45% of pts. receive RT as initial t/t.
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TMH Data (2007) 861 new cases. (5.3%)
M:F = 3.7:1 Median age = 56.9/52.8
Histology : SCC 055/861
Adenoca 336/861
SCC 206/861 NCSLC 099/861
Others 165/861
Only 37% cases are localised. 26% - distant mets. 3- locoregionally advanced.
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ANATOMY OF LUNG
Oblique fissure: extends fromthe lung surface to the hilum
Horizontal fissure: extendsfrom the anterior margin into
oblique fissure.
Rt lung: three lobes
Lt lung: two lobes, middle oneis replaced by lingula
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BRONCHOPULMONARY SEGMENTS
APICAL
ANTERIOR
POSTERIOR
MEDIAL
LATERAL
UL
ML
ANT BASAL
LA T BASAL
POST BASAL
MED BASAL
LL
APICAL
ANTERIOR
SUP SEG
INF SEG
LIN
ANTERO
BA
POSTERIOR
BASAL
LATERAL
BASAL
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LYMPH NODE MAP:Nomenclature*
*American College of Surgeons
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Lymphatic drainage
Right upper lobe
Tracheobronchial LN
Left upper lobe venous angle of same side as w
as opposite side.
Rt and lt lower lobe - subcarinal nodes and to Rt
superior mediastinum and directly into inferior
mediastinum
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STAGING Tx : primary tumour can not be assessed
T0 : no evidence of primary tumour.
T1 : tumour 3cm, involves main bronchus >2cm distal to carina, invades visceral pleura asso atelectasis or obstructive peumonitis not inv entire lung
T3 : invades diaphragm, mediastinal pleura, parietal pericardium, bronchus
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Nx : Regional lymph can not be assessed
N0 : No regional lymph nodal metastasis
N1 : Mets to ipsilateral peribronchial and/or ipsilateral hilar, andintrapulmonary nodes.
N2 : Mets to ipsilateral mediastinal and/or subcarinal nodes
N3 : Mets to contralateral mediastinal, contralateral hilar, ipsilateral orcontralateral scalene, or supreclavicular lymph nodes
M0 : No distal mets.
M1 : Distal mets present
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STAGE GROUPING
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WORK UP
Clinical history, Physical Examination
Performance Status, h/o wt loss
Hematological : CBC, Biochem, Sr. Alk Po4, LDH
Endoscopic findings
Imaging : X ray chest, CECT, PET/PET-CT Pleural fluid cytology if PE
Assessment of Cardiopulmonary function
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PET is now standard component of staging in nan
metastatic NSCLC pts. Considered superior to CT in determining TNM stage
Although CT with its better spatial resolution remains th
standard assessment
WORK UP
Modality Sensitivity Specificity PPV NPV
CT 57% 82% 56% 83%
PET 84% 89% 79% 93%
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HISTOLOGIC TYPES OF LUNG CANCER
2 major types:
Small-cell lung cancer
Nonsmall-cell lung cancer, which is further subdivide
into:
1. squamous cell carcinoma,
2. adenocarcinoma, and
3. large-cell carcinoma.
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Origin and characteristics
Squamous cell lung cancer: commonest type in males,
central origin, manifests early
Adenocarcinoma: commonest type in females, peripherorigin, manifests late
Large cell lung cancer: least common type, peripheral o
Small cell lung cancer: most aggressive type, central or
spreads quickly
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RT PLANNING
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POSITIONING AND IMMOBILIZATION
Pt taken on couch after explaining procedure and taking consent.
Immobilization done in supine position
Arms: Lateral
Above head
Neck: Neutral position and chin to SSN distance should be recorded
Normal breathing
Various immobilization boards can be used for better reproducible positVac lock can be used.
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Beam arrangement
AP/PA parallel opposed
Most commonly used
Lower integral dose to rest of the lung
Simple Comfortable
Easily reproducible
Spinal cord shielding
Post spinal block
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Radiotherapy treatment portals
Central
upper
lobe
periphera
upper
lobe
Ipsilateral supraclav to be included
Inferior margin 5-6 cm below carina
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No need to treat ipsilateral supraclav area
If mediastinal nodes are involved then ipsilateralSCF should be treated
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Phase II
Only primary tumour and
ipsilateral hilum with margin
for organ uncertainties.
To reduce dose to cord
To reduce dose to other critical structures
Field arrangement like ant + post oblique or both
oblique can be used
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Radiation dose
Radical (definitive) RT in stage I/II NSCLCmedically unfit patients for surgery
60 64 Gy / 30 32 #/ 6 7 wks
Phase I : 40 Gy / 20 # / 5 wks across mediastinum
Phase II : 10 Gy / 5 # off cord with 2 cm margin to
tumour
Phase III: 10 Gy / 5 # with 1 cm margin to tumour
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POST OP ADJUVANT RADIOTHERAPY IN EARLY
STAGE NSCLC STAGE I/II
Residual disease after lung resection
Resection with positive margins
Positive lymph node status
DOSE
50-54 Gy/ 25-27 fr/ 5-6 weeks
Phase I: 40 Gy/ 20 fr across the mediastinum
Phase II: 10-14 Gy/ 5-7 fr/2 cm margin (off cord).
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Radical Radiation therapy in stage III/IV NSCLC
Dose and fractionation
60-64 Gy/ 30-32 fr/ 6-7 weeks
Phase I : 40 Gy/ 20 fr/ 5 weeks across the
mediastinum
Phase II : 10 Gy/ 6 fr/ 2 cm margin to tumour (off
cord)
Phase III : 10 Gy/ 6 fr/ 1 cm margin to tumour.
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3D PLANNING
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Conformal techniques / 3DCRT
What is the need ?
Toxicity major problem
Dose escalation
some possibility
Already compromised CARDIOPULMONARY functio
because of Smoking, Cardiac morbidity , COPD,
Atelectasis.
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NORMAL TISSUE TOLERANCE TD 5/5
STRUCTURE 1 / 3 2 / 3 3 / 3SELECETEEND POIN
SPINALCORD 5000 5000 4700 MYLITIES
LUNG 4500 3000 1750
RADIATION
PNEUMON
HEART 6000 4500 4000 PERICARD
ESOPHAGUS 6000 5800 5500 STRICTUR
BRACHIALPLEXUS 6200 6000 6000
NERVEDAMAGE
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NORMAL TISSUE TOLERANCE TD 50
STRUCTURE 1 / 3 2 / 3 3 / 3
SPINAL
CORD 7000 7000 ----
LUNG 6500 4000 2450
HEART 7000 5500 5000
ESOPHAGUS 7200 7000 6000
BRACHIAL
PLEXUS 7700 7600 7500
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DATA ACQUISITION
Positioning and immobilization.
Reference markers placed
CT scan taken in treatment position. Contrast should be used.
Extends from thyroid cartilage to umbililcus
Slice thickness 5mm.
Spiral mode preferred over seq. mode
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STEPS Select proper window
Normal critical structures contoured first
GTV to be drawn
CTV and PTV to be generated
Images and RT structures then transferred to TPS.
Planning done.
Plan evaluation
DRR generated after plan approval.
DRR matched with sim / port film.
EPID taken for verification.
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IMPACT OF CT WINDOW LEVEL
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IMPACT OF PET ON RT PLANNING
PTV increased in 64% (detected nodes)decreased in 36% (exclusion of atelectasis)
(Erdi et al 2002)
Average reduction of PTV by 29%
Average reduction of V20 by 27%(Vanuytsel et al. 2000)
Interobserver variability reduced:
mean ratio of GTV without PET: 2.31
mean ratio of GTV with PET: 1.56
(Caldwell 2001)
IMPACT OF PET ON RT PLANNING
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Impact of PET: Atelectasis
IMPACT OF PET ON RT PLANNING
IMPACT OF PET ON RT PLANNING
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Impact of PET: PTV
IMPACT OF PET ON RT PLANNING
C O O
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Impact of PET: PTV
IMPACT OF PET ON RTPLANNING
IMPACT OF PET ON RT PLANNING
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Limiting factors of PET
-Resolution 4-8mm (depending on scanner and institution)
-Registration errors (esp. with software based fusion)
-Threshold value (SUV) individually to be determined
Summary:
PET is a promising complementary tool in RT planning of NSCLC. Its
for staging has been established and preliminary reports suggest that
may lead to more consistent definition of GTV in RT planning. Howeve
still not clear, whether this will translate into better survival.
IMPACT OF PET ON RT PLANNING
VOLUMES
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VOLUMES
GTV: Primary and Nodal disease as per Clinico
radiological findings
CTV: GTV + margins for subclinical disease
PTV: CTV + Margins for Set up error and Organ
motion ( Internal + External)
CTV t th b li i l i i di
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CTV to encompass the subclinical microscopic diseas
is difficult to define
Rarely mentioned in literature. Depends upon histological type and tumour volume.
Proposed margin : 5 15 mm
TMH: 0.7-1.0 cm margin around GTV
Microscopic extension Adeno Squamos
mean value 2.69mm 1.48mm
5mm margin covers: 80% 91%
margin to cover 95% 8mm 6mm
Phase1: Gross + Subclinical disease + PTV marginPhase2: Gross disease + PTV margin
(Giraud 2000):
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RT-Planning Defining the CTV
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RT-Planning Defining the CTV
Subclinical lymph nodes (ENI)
-high risk of nodal spread in lung cancer
-but value of ENI is not proven
Reasons against ENI:
-less than 20% locally controlled 1y after RT with conventional
dose (Arriagada 1991)
-need for more intense treatment to gross tumour-large volumes prevent dose escalation (normal tissue tolerance)
-small primary tumor and small total tumor volume predictive
(Basaki 2006, RTOG 93-11 2008)
-modern chemotherapy regimens may lead to better control of
microscopic disease
RT Pl i D fi i th PTV
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Created by adding margin to CTV
Based on institutional experience
Factors to be taken into account Set up uncertinties
Internal organ motion Respiration
Cardiac motion
Tumour location in lung
Fixation to adjacent structures
RT-Planning Defining the PTV
RT Pl i D fi i th PTV
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RT-Planning Defining the PTV
Reducing respiration induced errors:
Size of movement dependent on:- tumour location in the lung
- fixation to adjacent structures
- lung capacity and oxygenation
- patient fixation and anxiety
Average movement in normal breathing:- Upper lobe 0 - 0.5cm- Lower lobe 1.5 - 4.0cm- Middle lobe 0.5 - 2.5cm- Hilum 1.0 - 1.5cm
Steppenwoold
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SOME EXAMPLES
UPPER / MIDDLE LOBE TUMOUR AND
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UPPER / MIDDLE LOBE TUMOUR AND
HEART DOSES
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UPPER LOBE TUMOUR
MIDDLE LOBE CENTRAL TUMOUR
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(HEART)
MIDDLE LOBE TUMOUR (CORD
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MIDDLE LOBE TUMOUR (CORD
IMRT : non uniform dose intensity maps
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IMRT : non uniform dose intensity maps
Variabledoseacrossthefield
toachieveaspecificallydesignedintensitypattern
Sumofallfieldsin3Dspacedelivershighdosestoirregularlyshapedvolumes
ReducesV20 Non
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CONCERNS LIMITING USE OF IMRT Increased volume of lung receiving low dose of radiatio
resulting in more chances of radiation pneumonitis anddecrease in DLCO.
Impact of tumour motion.
Tissue inhomogeneity requires high degree of accuracdose calculaiton.
Although dosimetrically superior there is no robustevidence to suggest that it improves the health outcom
RESPIRATORY GATING
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RESPIRATORY GATING Technique to counteract the effect of target volume motion due to resp
Defines a physical window and delivers radiation when tumour passes radiation portal
Good compliance and pul. Functions
Video monitor and analyser characterizes breathing pattern and identifirange of chest wall motion.
Correlation of this data with tumour motion in simulation.
Create treatment that gates the treatment beam on when the tumour faplaned beam aperture.
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4D CT BASED RESPIRATION GATED RT
Treatment beam fixed in spaceand gated to turn ononly when
the target (or surrogate signal) comes into the pre-planned area
TOXICITIES
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TOXICITIES
Oesophagitis
Radiation pnemonitis acute / late
Radiation mylities
Brachial plexus injury
OESOPHAGITIS
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Concurrent chemotherapy and V60 weresignificantly associated with grade III esophagitis
LUNG TOXICITY For grade I RP
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LUNG TOXICITY
Related to both dose
and volume effect
Acute complication radiation pneumonitis
Late complication fibrosis
Severely debilitating
and fatal
For grade I RP
KPS
Tumour location
No previous surgeConcomitant
chemotherapy
gender
For grade II RP
High MLD
V20
, V30
MY SECONDLAST SLIDE
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MY SECONDLAST SLIDE
DONT use dose escalation and highly conformaltechniques such as IMRT for lung cancer until tumourmotion can be taken into account !
In the meantime ...
-Outline GTV as best as possible -Construct CTV based on the literature
-Construct PTV based on measured tumour motion andknown setup uncertainty.
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MONDAY SEMINAR 11/01/09
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MONDAY SEMINAR 11/01/09
Early Stage NSCLC: Stage I, II
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y g g ,
Standard of care = Surgery
Relapse rate 35%-50% in St. I
Relapse rate 40%-60% in St. II
Adjuvant radiotherapy ? Adjuvant chemotherapy ?
Adjuvant Radiotherapy
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Adjuvant Radiotherapy
Port meta-analysis Trialist Group. Lancet 1998;352:257
9 randomised trials of postoperative RT versus surger
(2128 patients)
21% relative increase in the risk of death with RT
Reduction of OS from 55% to 48% (at 2 years)
Adverse effect was greatest for Stage I,II
St.III (N2): no clear evidence of an adverse effect
Adjuvant Radiotherapy
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j py
Conclusion
Postoperative RT should not be used outside of
clinical trial in Stage I, II lung cancer, unless surg
margins are positive and repeated resection is nfeasible.
Adjuvant Chemotherapy
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Adjuvant Chemotherapy
Undetectable microscopic metastasis at diagnosis
Individual trials have not shown a significant benefi
Meta-analysis BMJ 1995;311:899:
Alkylating agents had an adverse effect
Cisplatin-based therapy:
13% reduction in risk of death (not significant)
P t ti Ch d R di th
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Postoperative Chemo- and Radiothe
ECOG-Trial: 488 patients with stage II, IIIA RT alone (50.4 Gy) versus
RT + 4x Cisplatin/Etoposid
Median survival 39 vs 38 months (ns) TRM 1.2 vs 1.6% Local recurrence 13 vs 12%
Keller et al. NEJM 2000;343:12
Cisplatin-based Adjuvant Chemotherapy(International Adjuvant Lun Cancer Trial Collaboratvie Gro
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(International Adjuvant Lung Cancer Trial Collaboratvie Gro
Randomised trial of 3-4 cycles of cisplatin-based
CT vs observation in patients with St. II, III LC
CT no CT
5-Y. DFS 39.4% 34.3% p
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Adjuvant Chemotherapy Conclusion:
One should consider the use of adjuvantplatinum-based chemotherapy in patients witstage I,II or IIA NSCLC
Locally advanced NSCLC
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Locally advanced NSCLC
Thoracic irradiation is the mainstay oftreatment for inoperable stage III dise
Its curative potential is extremely poor5-year survival rates 3-5%
Locally advanced NSCLC
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Locally advanced NSCLC
A meta-analysis of 22 randomised studishowed a beneficial effect of CT addedRT 10% reduction in risk of death per year
Small absolute survival benefit:4% after 2 years2% after 5 years
NSCLC Collaborative Group. BMJ 1995;311:
Neoadjuvant Therapy
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Neoadjuvant Therapy Pancoast`s tumor, vertebral invasion
Combined neoadjuvant CT-RT should be considered
Tumors with ipsilateral mediastinal spread (N2 Poor survival with surgery alone
2 small randomised trials showed a benefit of neoadjuvacombined CT-RT
Roth et al. JNCI 1994;86:673
Phase II trials report good results of neoadjuvant CT
SAKK Studies
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SAKK Studies SAKK 16/00
Preoperative CRT vs CT in NSCLC stage IIIA CT: 3 cycles docetaxel and cisplatin (D1,22,43) RT: 3 weeks of RT (44 Gy in 22 fractions)
SAKK 16/01 Preoperative CRT in NSCLC pts with operable
stage IIIB disease The same regimen as 16/00
Metastasis
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M40-50% at diagnosis
70% during follow-up
NSCLC: chemotherapy combinations
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NS L ch moth rapy com nat ons
Regimes
Cisplatin+Paclitaxel
Cisplatin+Gemcitabine
Cisplatin+Docetaxel
Carboplatin+paclitaxel
Results (n=1155 pts.)
Response rate 19%
Median survival 8 mont
1-year survival 33% 2-year survival 11%
Schiller et al. NEJM 2002;34
Conclusion: Combined-Modality Therapy forStage III Disease
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Stage III Disease
Adding CT to radiation therapy improves survival and alterscourse of this disease
Phase III studies suggest improvement in both local contro
survival with concomitant CT-RT
Combined CT-RT should be the standard of care of patient
good PS and minimal weight loss
The absolute gain from combined CT-RT is still modest
The role of surgery following induction CT-RT is for patien
with unresectable Cancer is being explored
Small-cell Lung Cancer (SCLC)
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g ( )
15-20% of all lung cancer
Incidence: 15/100000/year
Men : women = 5 : 1
SCLC
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Rapid local and metastatic spread Mediastinal lymph node metastasis in most
cases
Median Survival in untreated patients 2-3
months Superior vena caval obstruction and
paraneoplastic syndromes (SIADH, Cushin
Association with smoking
SCLC Staging
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g g Limited Disease
Confined to:
One hemithorax Mediastinum
Ipislateral hilarand supraclavicularnodes
Extensive Disease
Malignant pleuraand pericardeffusion
Contralateral hilaand supraclaviculanodes
SCLC Therapy
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py No surgery; SCLC is a systemic disease
Chemotherapy is the standard of care Cisplatin+Etoposid
Limited stage SCLC: Bimodality therapywith chemotherapy and radiotherapy
SCLC Therapy
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py
The addition of thoracic RT significantly improsurvival in patients with LS-SCLC
Meta-analysis. Pignon et al. NEJM 1992;327:1618
14% reduction in the mortality rate
5.4% benefit in terms of OS at 3 years
Early use of RT with CT improves cure rates
SCLC Therapy
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py
The actuarial risk of CNS metastasis develo2 years after CR of SCLC is 35%-60%
Prophylactic cranial Irradiation is recommend
for pts. With LS-SCLC in CR
Meta-analysis: Auperin et al. NEJM;1999:341 PCI: 5.4% greater absolute survival at 3 year
SCLC Results
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Limited Disease:
Remission rate 80-90% CR 50-60%
Median Survival 18-20 months 2-year Survival 40% 5-year Survival 15-25%
SCLC Results
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Extensive Disease:
Remission rate 70-80% CR 20-30%
Median Survival 8-10 months 2-year Survival < 10%
FLUROSCOPY
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Average movement with respiration in each patient should berecorded
Eikberg et al : 200 patients2.4 cm in ML directions3.9 cm in cranioquadal directions
Huang et al :distal hilum 1 1.5 cmarch 0-0.5lower lobe 1.5 4 cmmid lobe 0.5 2.5 cm
TUMOUR EDGE DEFINITION
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Visual interpretation of PET images.
arbitrarily windowing, may lead significantly different appar
tumour volumes
Automatic Image segmentation methods based on SUV eithe
as an absolute SUV.
a SUVmax of 2.5 is often used as a threshold for the distinction betwmalignant and benign lesions.
threshold value (a percentage of SUV max)
40% to 50% of the maximum uptake
15% for moving targets
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Important role in differentiating disease from benigpulmonary nodule and from atelectasis.
As ENI is not routinely delivered, PET CT may helin identification of involved nodal areas.
Despite better tumour volume deliation and reductof interobserver variation there is not enough robuevidence to suggest that it improves the outcome.