Page 114 - Read Online

Youbi et al. Management of choroidal metastasis using external beam radiotherapy

metastases, probably due to anatomical reasons volume CTV was the posterior uvea-choroid of the eye.
and blood vessel supply. The treatment of these The planning target volume PTV represented CTV with
[3]
tumor localizations is not yet standardized but is a margin varying between 0.5 cm and 1 cm. The use
based mostly on external radiotherapy, which with its of magnetic resonance imaging (MRI) and merge it
sophisticated new techniques allows better results with the dosimetric scanner could help delineating the
while protecting healthy organs around. [4,5] We target volume with precision for a better planning of
conducted a retrospective study and synthesis of the the treatment plan which will make it possible to give a
literature to determine the interest of radiotherapy in large dose to the target volume to be treated (choroid)
the management of choroidal metastases. and sparing the risky organs beside it [Table 2].

METHODS Statistical analysis
SAS JMP 11 software (SAS Institute Inc. Cary, NC,
®
Patient characteristics USA) was used for statistical analysis. An overall
We reviewed the cases of 28 patients treated in our description of the population was carried out. For
center in the period between August 1996 to June qualitative data, numbers and percentages were
2015 and presenting choroidal metastases in a context calculated. Quantitative data, median or mean by
of solid cancer, excluding melanomas. All information normality, as well as extreme values with minimum
regarding the date and site of the primary tumor, status and maximum were estimated. Fisher’s exact test
of the primary at the time when choroidal metastasis was used to determine the association between two
was diagnosed, date of choroidal metastatsis diagnosis, qualitative variables with a significance level P < 0.05.
symptoms, localization and number of lesions in the
eye, radiation treatment and technical parameters RESULTS
was collected. All the ophthalmological examinations
were done in the ophthalmology department of our Patients had cancer of breast (n = 15), lung (n = 9),
center, and then sent to our department for oncological ovarian (n = 1), kidney (n = 1), prostate (n = 1), with
management by radiotherapy [Table 1]. an unknown primitive at the moment of the diagnosis
(n = 1). The median age was 58 years [extreme (E):
Radiotherapy 34 to 71 years]. Our cohort contained 19 women and
For each patient, excluding those treated in two- 9 men (sex ratio = 0.47). The tumor stage before the
dimensional radiotherapy (2D), a scanner with a slice discovery of choroidal metastases was metastatic for
thickness of 2.5 mm was performed in treatment 48% of the patients. Eye involvement was unilateral
position using a thermoformed contention mask
to maintain a reproducible position throughout the Table 2: Results of external beam radiotherapy in our
treatment. Treatment plan was performed using the cohort
ECLIPSE TM treatment planning system (VARIAN , Characteristics Effective
®
Palo Alto, CA, USA). The treatment was delivered with Total dose (splitting)
a VARIAN CLINAC Linear Accelerator. The doses 20 (4) Gy 4
®
20 (5) Gy
1
varied from 20 Gy to 50 Gy with a fractionation of 3 Gy 24 (4) Gy 2
to 5 Gy in two-dimensional 2D (n = 5), conformational 30 (3) Gy 18
30.5 (2.5) Gy
1
3D (n = 21), intensity modulation (n = 2). The most used 37.5 (3.5) Gy 1
prescription regimen consisted of delivering 30 Gy 50 (4) Gy 1
Irradiation techniques
into 10 fractions of 3 Gy (n = 18). The clinical target IMRT 2
2D 5
3D 21
Table 1: Clinical characteristics Acute toxicity
No toxicity 22
Characteristics Effective Headache grade 1 4
Gender Eye pain grade 1 1
Man 9 Radiodermitis grade 1 1
Women 19 Latetoxicity
Medianage 58 years (34-75 years) No toxicity 28
Primary tumor localization Improvement of initial ophthalmologic symptoms
Lung 9 Yes 13
15
No
Breast 15 Visual improvement based on dose
Ovarian 1 20 (4) Gy 2 (50%)
Kidney 1 20 (5) Gy 1 (100%)
Prostate 1 24 (4) Gy 1 (100%)
Unknown primitive 1 30 (3) Gy 7 (35%)
Tumor stage before discovery 30.5 (2.5) Gy 0 (0%)
Localized 13 37.5 (3.5) Gy 1 (100%)
Metastatic 15 50 (4) Gy 1 (100%)
106 Journal of Cancer Metastasis and Treatment ¦ Volume 3 ¦ June 30, 2017