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ESTRO 36 2017
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department, Saint-Petersburg, Russian Federation
6
Dr. Berezin Medical Center, Radiology department,
Saint-Petersburg, Russian Federation
7
Russian Scientific Center Of Radiology And Surgical
Technologies, Radiation Therapy department, Saint-
Petersburg, Russian Federation
Purpose or Objective
Locoregional recurrence is a major cause of death in
patients with squamous cell carcinoma of the head and
neck (HNSCC). At the moment, there are no clear
recommendations and standards regarding the timing,
total doses and dose tolerance of normal tissues to re-
exposure. Based on limited studies on the re-irradiation
with high total doses, we evaluated the tolerability and
clinical outcomes of high-dose chemo-reirradiation with
simultaneous integrated boost.
Material and Methods
18 patients with histologically confirmed locoregional
recurrence of HNSCC, received chemo-reirradiation.
Median time after primary radiotherapy course was 60
months. The treatment volumes and total doses were
formed as follows: GTV (primary lesion and involved lymph
nodes, delineated on CT, MRI and
18
F-FDG PET-CT) + CTV
(0.5-1.0 cm) + PTV (0.3-0.5 cm) was treated to the total
dose equivalent to 66-70 Gy of conventional fractionation,
the high-risk lymph nodes (if indicated, PTV 0.5 cm) to 60
Gy, the low-risk lymph nodes (if indicated, PTV 0,5 cm) –
equivalent to 50 Gy. Single doses to these volumes were
2.14-2.21 Gy, 2.0 Gy and 1.8 Gy, respectively. Radiation
treatment was once a day, five days a week, 6 weeks long
(30 fractions). Varian Eclipse v.10 was used for treatment
planning (IMRT and VMAT); patients were treated on
Varian Clinac 2100 and Varian TrueBeam STx. According to
the literature, in a year after primary irradiation almost
complete recovery of normal tissue tolerances is
observed. Tolerances of organs at risk were not exceeded.
IGRT was used for patient positioning. Patients received
cisplatin every three weeks, 100 mg/m
2
.
Results
16 of 18 patients received full course of radiation therapy
without a break. Radiation toxicity manifested with grade
2-3 oral and pharyngeal mucositis and grade 2 radiation
epidermitis. After one month, almost complete relief of
radiation mucositis and dermatitis was observed. One
patient took a break of 7 days after 25th fraction due to
the development of grade 3 mucositis and grade 3
dysphagia. Late toxicity were grade 2 xerostomia in 1
patient (recurrent tumor, located near the parotid
salivary glands), chronic atrophic sinusitis - in 2 patients
(recurrence in the ethmoidal labyrinth and maxillary
sinus). In 14 patients, who received re-irradiation with a
total dose of more than 60 Gy, partial response was
observed at the first follow-up examination (MRI) at 1
month after treatment. Two patients showed
stabilization. Median follow-up was 11 months (from 2 to
20). One year overall survival was 48%. The cause of death
in two patients was disease progression (distant
metastases), two patients died from complications related
to the treatment (elderly patients, who developed grade
3 dysphagia and subsequent septic complications).
Conclusion
Using technique of SIB with IMRT/VMAT during curative
chemo-reirradiation of recurrent HNSCC is available with
maintaining satisfactory tolerability. Local control rate is
quite encouraging, and late toxicity is at acceptable rates.
EP-1044 survival and functional outcome after
treatment for primary base of tongue cancer
S. Park
1
, Y. Cho
1
, J. Lee
1
, K.C. Keum
1
, C.G. Lee
1
1
Yonsei university college of medicine, Radiation
oncology, Seoul, Korea Republic of
Purpose or Objective
The preservation of speech and swallowing function in the
treatment of base of tongue (BOT) cancer is critical issue.
At present, BOT cancer patients treated with either
surgery followed by postoperative radiotherapy or
definitive RT without consensus of optimal treatment. The
purpose of this study is to compare the clinical and
functional outcome in patients with primary BOT cancer
who received definitive radiotherapy or surgery followed
by radiotherapy.
Material and Methods
Between January 2002 and June 2016, a total number of
99 patients with stage I-IVB primary BOT squamous cell
carcinoma underwent either definitive radiotherapy (RT
group, n=43) or surgery followed by radiotherapy (SRT
group, n=56). In the RT group, 28 patients (65.1%) were
treated with concurrent chemotherapy and 11 patients
(25.6%) with induction plus concurrent chemotherapy. In
the SRT group, 18 patients (32.1%) received concurrent
chemotherapy. Median radiation doses of the RT group and
SRT group were 70 Gy (range, 63-76 Gy) and 63 Gy (range,
45-68.4 Gy), respectively. Radiotherapy was performed
using both 3-demensional conformal RT (3D CRT, n=30)
and Intensity modulated RT (IMRT, n=69). Among patients
in SRT group, 31 patients (55.4%) were treated with wide
excision, 18 (32.1%) with partial glossectomy, and 7
(12.5%) with total glossectomy. Expression of p16 was
available in 53 patients (53.5%). Among these, 38 patients
(71.7%) had p16 positive and 15 patients (28.3%) had p16
negative BOT cancer.
Results
The median age of patients was 59 years (range, 36-96).
There were more patients that had advanced T stage (T3-
4) disease (58.1% vs. 37.5%, p=0.041) and received
chemotherapy (90.6% vs. 35.7%, p=0.001) in RT group than
those in SRT group. At a median follow up of 36.1 months
(range, 0.8-178.4), 5-year overall survival (OS) and disease
free survival (DFS) were 74.6% and 69.6%, respectively.
Respect to treatment group, 5-year OS and DFS in both RT
group and SRT group were 71% vs. 77.2% (p=0.941) and 65%
vs. 72.9% (p=0.805), respectively. In univariate analysis, T
stage (OS: p=0.041, DFS: p=0.008), RT modality (OS:
p=0.004, DFS: p=0.002) and p16 expression (OS: p=0.009,
DFS: p=0.009) were observed prognostic factors related to
both OS and DFS. In multivariate analysis, OS showed
significant difference according to p16 expression (p16
negative vs. p16 positive, HR 0.152, 95% CI 0.028-0.816,
p=0.028). Regarding DFS, p16 expression (p16 negative vs.
p16 positive, HR 0.261, 95% CI 0.073-0.936, p=0.039)
showed significant effect in multivariate analysis.
Dysphagia and voice alteration (severe than grade 2) were
more frequently observed in SRT group than RT group
(19.6% vs. 2.3%, p=0.009).
Conclusion
Even with more advanced disease, patients in RT group
showed comparable survival outcome with better
functional preservation to those in SRT group.
EP-1045 L Glutamine in reducing severity of oral
mucositis due to chemoradiation in head and neck
cancer
V. Pareek
1
, R. Bhalavat
2
, M. Chandra
2
1
Jupiter Hospital- Thane, Radiation Oncology, Mumbai,
India
2
Jupiter Hospital, Radiation Oncology, Thane, India
Purpose or Objective
The incidence of mucositis in the oral cavity, pharynx and
larynx is high among patients with head and neck cancer
(HNC) receiving chemo-radiotherapy (CRT), resulting in
significant pain and impairment of quality of life. The
present study investigated whether L-glutamine
(glutamine) decreases the severity of mucositis in the oral
cavity, pharynx and larynx induced by CRT
Material and Methods