ESTRO 36 Abstract Book

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S574 ESTRO 36 2017
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Purpose or Objective
To report our finding that image-based diagnosis of
recurrent nasopharyngeal carcinoma (rNPC) may not be
real recurrence，the "phantom tumor" phenomenon.
Material and Methods
From January 2010 to July 2016, we collected 16 cases of
image-based diagnosis of recurrent nasopharyngeal
carcinoma who have been subsequently confirmed to be
not genuine recurrence by pathological biopsy or by the
absence of EB viral load & long-term follow-up. Analysis
was conducted for imaging features and clinical
manifestations of these patients with images mimicking
recurrence or residual lesion.
Results
There are 2 types of image patterns of this “phantom
tumor”phenomenon. The most common one is
characterized by extensive skull base lesions (11/16), and
the other one is persistent or residual primary lesion
(5/16). 13 cases were confirmed by pathological diagnosis
(13/16), with histological findings of necrosis,
inflammation, or granulation tissue. 3 cases had no
pathological proof (3/16) and were judged to have no real
recurrence/residual tumour by negative EBV DNA copy
number as well as physical & fiberoscopic results. EBV viral
load is 0 in 93.8%（15/16）of patients, and one did not
have EBV viral load test.Nasopharyngeal necrosis by
nasopharyngoscopy was noted in 56.3%（9/16）of
patients, and cranial nerve palsy by physical examination
in 43.8%（7/16）of patients.
Conclusion
Image-based diagnosis of recurrent nasopharyngeal
carcinoma ，especially images showing extensive skull
base involvement，is unreliable, especially in T4 NPC
patients. Some of these lesions are not real recurrence but
benign pathological changes of the skull base including
necrosis, inflammation or granulation tissue. Images
showing persistent or residual primary lesions may also be
misleading.Biopsy must be conducted with every effort to
confirm recurrence or residual tumor. Without a
pathological confirmation, the possibility of a “phantom
tumor”is likely, and the final diagnosis must be made
taking into account of endoscopic findings & EBV viral
load. A second irradiation of a patient with a phantom
tumor must be avoided which is certain to bring some
irreparable damages or death to the patients.
EP-1049 Intensity-Modulated Radiotherapy(IMRT)
could provide better outcomes for nasopharyngeal
carcinoma.
P. Pattaranutaporn1, N. Ngamphaiboon2, T. Chureemas 2,
J. Juengsamarn2, S. Lukerak 2, R. Sophonsakulchot2, C.
Jiarpinitnun1
1 Faculty of Medicine Ramathibodi Hospital- Mahidol
University, Division of Radiation Oncology- Department
of Radiology, Bangkok, Thailand
2 Faculty of Medicine Ramathibodi Hospital- Mahidol
University, Division of Medical Oncology- Department of
Medicine, Bangkok, Thailand
Purpose or Objective
Intensity-Modulated Radiotherapy(IMRT) has shown
significant benefits for nasopharyngeal carcinoma in term
of normal tissues sparing especially for the salivary glands.
However, its benefit on treatment outcomes was
controversy. This study was aimed to determine the
treatment outcome benefits of IMRT over conventional
radiotherapy in nasopharyngeal carcinoma.
Material and Methods
Stage I-IVb Nasopharyngeal carcinoma patients who
treated with definitive radiation or chemoradiation at our
hospital between 2007 and 2014 were identified through
the cancer registry database. Patient characteristics,
radiotherapy, chemotherapy and medical records were
retrospectively reviewed. Locoregional failure, distant
failure and survival were analyzed in overall population
and by radiation technique (Conventional vs IMRT).
Results
From 2007 to 2014, a total of 187 stage I-IVb
nasopharyngeal carcinoma patients were treated with
definite radiation or chemoradiation at our hospital. Of
these, 107 and 80 patients were treated with conventional
radiotherapy and IMRT, respectively. Conventional
radiotherapy was mostly 3D conformal radiotherapy with
20 patients (18.69%) were 2D radiotherapy. Patient's
characteristics and tumor stage were generally similar in
both groups except patients with conventional
radiotherapy had earlier year of treatment. Median
follow-up time for survival were 64.7 and 37.8 months for
conventional and IMRT groups. Radiation therapy was
delivered in 180-200cGy per fraction for conventional
radiotherapy. IMRT was usually delivered with
Simultaneous Integrated Boost (SIB) technique with
radiation dose per fraction ranged between 163-220cGy
per fraction. Median total radiation dose were 7020cGy for
conventional group and 6996cGy for IMRT group. 94.12% of
patients received concurrent chemoradiation. 3-year
locoregional failure (LRF) were 11.34% and 5.91% for
conventional and IMRT group, respectively (p=0.2082).
Disease-free survival (DFS) was marginal significant
difference between conventional and IMRT group, 3-year
DFS were 71.46% and 80.96% (p=0.0762). However, 3-year
overall survival (OS) was not significant difference
between conventional and IMRT group at 76.13% and
81.83%, respectively (p=0.2856).
Conclusion
In our experience, IMRT showed marginal significant DFS
benefit and trended to have better locoregional control
and overall survival.
EP-1050 Prognostic factors analysis in advanced
SCCHN treated by induction chemotherapy/local
therapy
C. Wu1, H.Y. Hsieh2, Y.C. Liu2, W.Y. Wang3, J.C. Lin 2
1Changhua Show-Chwan Memorial Hospital, Radiation
Oncology department, Changhua, Taiwan
2Taichung Veterans General Hospital, Radiation
Oncology, Taichung, Taiwan
3Hung Kuang University, Nursing, Taichung, Taiwan
Purpose or Objective
To investigate the prognostic factors in patients with
advanced squamous cell carcinoma of the head and neck
(SCCHN) who received a novel weekly induction
chemotherapy (IndCT) followed by local therapy
(surgery/radiotherapy).
Material and Methods
Fifty patients with stage III/IV SCCHN were enrolled.
Outpatient IndCT consisted of an uniform 4-drug regimens
(cisplatin 60 mg/m2, day 1; docetaxel 50 mg/m2, day 8;
5-fluorouracil 2500 mg/m2 + leucovorin 250 mg/m2, day
15; epirubicin 30 mg/m2 + methotrexate 30 mg/m2, day
22; repeated every 4 weeks for 3-4 cycles). After finishing
IndCT, local therapy including surgery, radiotherapy,
concurrent chemoradiotherapy, or bio-radiotherapy was
administered. Univariate and multivariate Cox
proportional hazard model were used to identify
significant prognostic factors. Analyzed variables included
patient’s characteristics (age, gender, performance
status), tumor factors (primary site, pathological
differentiation, T-stage, N-stage), treatment factors
(chemotherapy, surgery, radiotherapy) and pre-treatment
FDG PET scan parameters (SUVmax of primary tumor,
metabolic tumor volume [MTV], total lesion glycolysis
[TLG]).
Results
After a median follow-up of 25 months, 13 patients
experienced locoregional recurrence, 1 distant
metastasis, and 1 both locoregional recurrence and distant