Lung

Question 1

For treatment purposes NSCLC can be divided into Early and Late based on:

Answer 1

1) Early = <Stage III
2) Late Stage III
Stage III is node +ve or T4 disease,
with the exception that T1-2 w/ +ve N1 node (i.e. Ipsilateral peribronchial and/or ipsilateral hilar LNs = stations 10–14) is stage II (i.e early).

Question 2

Define stage III NSLC

Answer 2

1) Either T4 = >7cm OR Satellite nodules in different lobes ipsilateral lung, or invasion: thoracic structures beyond pericardium, phrenic n. or chest wall (these are T3)
2) Any nodal disease, except N1 with only T1 (<=3cm) or T 2 (>3cm, <=5cm - without invasion)

Question 3

In NSCLC contrast the definition of T3 and T4 disease:

Answer 3

In T3 disease, any satellite nodule needs to be within the same lobe
In T4 in different lobes same lung
Invasion in T3 is pleura, chest wall, or phrenic nerve. T4 is any other structure.
Size: T4 is >7cm, T3 is >5cm to =7cm.

Question 4

A 60yro moderate smoker is found on screening to have a 5.0cm upper lobe lesion, subsequent PET demonstrating only the primary lesion and a single ipsilateral peribronchial node. What is the grade? What is the most likely Tx

Answer 4

T2 (=5cm, not invasive therefore T2)
Peribronchial is an N1 node.
T2N1M0 = stage IIB = Early.

Surgery - VATS lobectomy and MLND
- Ginsberg (1991) would suggest 88% cancer free survival (vs 75% w/wedge)
Adjuvant chemo - As per LACE - adds ~5% OS benefit at 5 years (for stage II/III)

NB: except in Japanese cohort no CTx benefit for 1A, 1B benefit is debated. 1B = 3.1-4cm (ie. T2a), T2b (4.1-5) = stage IIA….

Question 5

In NSCLC define “peripheral tumour”

Answer 5

“peripheral tumour” = more than 2cm from bronchial bifurcation.

Question 6

Define the “N1 nodes”

Answer 6

Ipsilateral peribronchial and/or ipsilateral hilar LNs (stations 10–14)

Question 7

Poor prognostic factors for NSCLC:

Answer 7

Stage, weight loss >5% in 3 months, KPS <90, age >70, +LVSI, marital status

Question 8

Indications for PORT in NSCLC

Answer 8

1) +ve margins in early stage disease. PORT is not indicated in completely resected stage I-II patients as per meta-analysis.
2) Stage III - Lung ART RCT study looked at N2 disease - found no benefit (DFS or OS) to PORT 54/30 in completely resected N2 disease. PORT-C study confirms this. OS at 3yrs is about 80%

Question 9

For stage III NSLC patients not fit for chemo or radiation what fractionations are available? Comment on any advantages?

Answer 9

60/30 = conventional

Various hypofractions have been studied, with phase III/RCT suggesting no clear benfit to either.
60/15, 45/15, 30/10.
E.g recent Northwestern trial compared 60/30 to 60/15 in terms of superiority (for stage II&III, no CTx) - no clear benefit, but trend favouring hypo, also had less acute grd II toxicities - which may be good for frail Pts.

Question 10

For early- stage NSCLC What are the outcomes with conventional RT (give doses)

Answer 10

Historically conventional RT gave LC around 40% to 60%, with 30-40% of patients died within 2 years. Old evidence of dose escalation to 70.2 Gy and hypofractionation (60 Gy/15 fx)

Question 11

For late stage NSCLC treated w/CTxRT, does dose escalation offer any benefit?

Answer 11

Bradley, RTOG 0617 (2015) Prospective RCT, 60 Gy/30 fx VS 74 Gy/37 fx with concurrent carboplatin AUC 2/paclitaxel weekly.

74 Gy is harmful and not superior.

Question 12

For late-stage NSCLC, what is the benefit of adj immunotherapy

Answer 12

PACIFIC trial established the benefit of adj Durvalumab. Median PFS increased by 1 yesr (from 6 months to 17). OS at 3yrs increased by 13% (57%vs 44%)

Question 13

2 most common paraneoplastic syndromes associated with NSCLC, Give MOA, Ix and Tx:

Answer 13

1) Hypercalceamia of malignancy (most common): Sx: Stones, Bonesm Abdo moans and psych groans (lethargy/fatigue/mood changes/cog). In SCC PTH receptor-like protein PTHrP, other mechanisms osteolytic mets, PTH secretion, GCSF.
Ix: Serum ionised C, Alb, Ca, [PTH], other: ECG, LDH, RFTs
Tx: Isotonic saline (reverse hypovolemia, improve clearance) 24-48hrs, refractory give bisphosphantes (e.g Zoledronic acid) 2-4 days for effect.
2) SIADH (1%NSCLC, 10-45% SCLC)

Question 14

For early NSLC what is the benefit of SABR compared with conventional (give evidence):

Answer 14

TROG CHisel

Question 15

Why is it important to investigate the mediastinum in early-stage NSCLC. Compare the sensitivities of the different methods of Ix

Answer 15

Tx decisions based on node status. Reliable staging of mediastinum is essential.
PET/CT has sensitivity of 79% (CT staging 60%)
Investigation of the mediastinum via either mediastinoscopy or EBUS can improve this.
(see other slide)

Question 16

Mediastinoscopy vs EBUS

Question 17

Side effects of lung SABR:

Answer 17

Short-term:
Likely to be very well tolerated. May experience fatigue, cough, erythema over treatment site.

Long-term:
Lung scarring/fibrosis - with (likely) subclinical decrease in DLCO
Chest wall discomfort or pain adjacent treatment site. With increased risk of rib fractures.
Pleural effusion,
Randomised control data for SABR suggests pneumonitis is more a volume effect and is very unlikely given patient’s PTV.
Second malignancy.

General other location dependent (i.e. not this patient) effects:
Pericarditis
Brachial plexopathy

Question 18

Outline a suitable dose/technique for a patient with T1b RUL lung SCC which is more than 2cm from bronchi bifurcation and chest wall.

Answer 18

Curative intent EBRT - SABR VMAT technique 30Gy/1# (or 54/3 preferred) to the RUL lesion, encompassing an iGTV and PTV. Prescribed to 100% isodose.

Pre sim:
Optimise competence/compliance and communication. Involve psych, social and cultural support to achieve this.

Sim:
Supine, arms above head, immobilisation w/vac bag, knee and neck supports
3D and 4D fine slice (<=3mm) CT from above SCF to below diaphragm
Free breathing, with other options (Gating) available if significant motion.

ITV created on MIP tumour in lung windows, then viewed in the 4-D dataset to ensure that all tumour is contained within the ITV throughout respiration.

Treatment
Dose delivered with soft 4DCT target matching. And respiratory monitoring.