TOXICITY & LOCAL CONTROL IN HEAD & NECK CA RADIOTHERAPY

1. Dr. Gopa Ghosh M.D.
Associate Professor(Radiotherapy)
Chirayu Medical College & Hospital, Bhopal
Co Authors:
1.Dr.Gaurav Gupta.
2.Dr.Anupam Malviya
CLINICAL OUTCOME OF IMRT vs 3D-CRT in Head
& Neck Cancer- A retrospective comparison

2. Background & objectives
 With greater control on dose distribution within the target, IMRT allows
higher possibility to sculpt radiation dose thereby improving the
therapeutic ratio.
 PARSPORT was the first trial comparing IMRT with conventional
radiotherapy in H&N cancer, which showed reduction in severe
xerostomia but no difference in non xerostomia toxicity. 24months
follow up showed no difference in loco regional or overall survival.
 Objectives:
 To compare clinical outcome in terms of toxicity profile and local
control (LC) of IMRT with 3D CRT in head and neck cancer
retrospectively.
 Compare our observations with results of other similar studies.

3. PATIENTS AND METHODS
 Between 2013 to 2015, 40 patients of cancer buccal mucosa and alveolus received post-
operative (19) or definitive (21) RT by IMRT.
 RT doses were between 60-70 Gray @ 2 Gray/ fraction, with concurrent Cisplatin
chemotherapy in around 73%.
 Patient outcomes i.e. toxicities and LC were analyzed for significance of results
retrospectively from patient records. .CSS analyzed with kaplan-meir curves
 IMRT cohort was compared to 42 conventionally irradiated (3DCRT) definitive or
postoperative patients.
Indications of post- op Radiotherapy in H&N ca:
 Close( <5mm) or positive margin, ECE , PNI, LVSI
 Advanced T-stage,2 or more lymph node involved, Invasion of soft tissues of neck
,recurrence.
Prognosis following post- op RT depends:
 Risk group, ,Interval between surgery and RT(<51 days) [VikramB, Hinnerman et al,
Rosenthal et al]
 Overall duration of treatment ,Surgery to completion of RT(<101 days).
 Dose of Radiotherapy ≥ 60 Gy [Schiff et al, Ang et al.] ]

4. PATIENT CHARACTERISTICS
Characteristics Number (%)
IMRT 3DCRT
N 40 42
Age/sex ratio 31-65/ 4:1 21-77/4:1
Sub site
1.Buccalmucosa
2.Alveolus
26
14
30
12
T-STAGE: 1-2 11 11
3-4 29 31
Overall stage: II 3 (7.5) 2 (4.7)
III 10 (25) 10 (23.8)
IVA
20 (50) 22 (52.3)
IVb
7 (17.5) 8 (19.04)
CRT
(chemoradiotherapy)
29(73%) 31 (74%)

5. ACUTE & LATE TOXICITY %(IMRT/CRT)RTOG
AUTHOR
S
FUP
in mo.
MUCOSITIS DERMATITIS DYSPHAGIA
(ACUTE/LAT
E)
XEROSTOMIA
(ACUTE/LATE
)
Present
study
24 Gr-II
60/72.5
p-0.34
Gr-III
40/57.5
p-0.17
Gr-II
92.5/87.5
p-0.7
Gr-III
7.5/12.5
p-0.7
Gr -II
57.5/ 85
p-0.013
Gr1
7.5/10
Gr- II
45/72.5
p-0.023
Gr I –II
27.5/57.5
Nutting et
al
24 - - - 29/83
p-0.0001-
Wen
cheng et
al
36 - - 21/59
p-0.02
36/82
p-0.01
Lambrec
het et al
35 32/44
p-0.03
- - 23/68
p<0.001

6. LRC-Definitive versus Post-op. approach with IMRT compared to 3DCRT
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 6 12 18 24 30 36
Post-Op. 3D-CRT
Post-Op. IMRT
Definitive IMRT
Definitive 3D-CRT
Researchers DFS
IMRT/3DCRT %
P-value FUP in
years
Present study 89/79 0.0001 2
James .B.Yu
et al
60/58.8 0.45 3
Vassillis et al 83.6/74.4 0.024 3
Beth.M. et al 84/66 0.01 3

7. CONCLUSION
 In the present study ,IMRT is associated with a significantly lower
incidence of Grade 2 or greater xerostomia, acute toxic effects to skin and
mucosa. Less feeding tube use during radiotherapy compared to 3DCRT.
 Postoperative IMRT of ca. buccal mucosa and alveolus resulted in better
LC of all the assessed subgroups, possibly owing to better PTV
coverage/lesser treatment breaks. Definitely irradiated patients showed
similar LC in both arms
 Improved LC rates with postoperative IMRT, reduced late toxicities like
xerostomia and dysphagia may supports its early implementation
especially in the post-operative setting
 Our study sums-up that IMRT reduces severe late xerostomia and
dysphagia without compromising tumour control.
 Meticulous planning and higher integral dose are areas of concern.

8. Thank
you.