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Advances in Radiotherapy
& Nuclear Medicine Hypofractionated radiotherapy in craniopharyngioma

craniopharyngioma presents no gender difference but a intensity-modulated RT technique (H-IMRT) technique.
bimodal age pattern in the 5 – 15 and 50 – 75 age groups. For the conventional RT scheme, delivered through HT,
Headache, visual problems, endocrine abnormalities, doses of 50 and 55 Gy in 25 – 30 fractions were chosen
and failure to thrive are the most common symptoms of to treat the post-operative residual tumor. The cystic
craniopharyngioma. These symptoms appear a year before component and the boundaries of the pre-operative
2
diagnosis due to the organic growth of the tumor. tumor extent with a margin of 1 – 5 mm were taken
Neuroimaging, such as magnetic resonance imaging into consideration, depending on the accuracy of the
(MRI) of the brain or computed tomography (CT), is treatment planning images and the proximity to critical
the cornerstone of diagnosis for craniopharyngioma. structures, especially the optic chiasm. Therefore, both
2
Suprasellar calcifications and cystic lesions are usually pre-operative and post-operative multi-sequence MRI
present on diagnostic imaging. The endocrine system must images were used by rigid registration with planning
be assessed, and the necessary tests must be carried out CT images. Due to the high accuracy of planning with
before treatment can be planned. Radical resection has HT daily MV CT, a reduction of the margins could be
been the cornerstone of craniopharyngioma treatment for achieved. Furthermore, during RT, daily cone-beam
several decades and is associated with a relapse rate of 20 CT allows superficial monitoring of intratumoral cystic
– 30% after radical resection. In contrast, the recurrence changes without MRI. For CK planning, the same rigid
3-5
rate after incomplete resection is approximately 70%. fusions were used, but with smaller margins (0 – 2 mm)
6
Despite being the ideal treatment, complete resection is from gross tumor volume (GTV) to planning target
difficult to achieve in many cases due to the proximity volume (PTV) due to intrafractional tracking with 6D
of the tumor to critical structures such as optic pathway, skull tracking system. A thermoplastic mask was used in
hypothalamus, and pituitary. Therefore, currently, there is combination with image guidance techniques to ensure
no consensus regarding the optimal treatment. However, immobilization and treatment accuracy. In addition,
7
results presented in a published paper have drawn an patients with compressive symptoms underwent surgical
increasing attention to radiotherapy (RT) being a feasible decompression before radiation to prevent worsening of
treatment for craniopharyngioma. 3 compressive symptoms due to radiation-induced edema.
External beam radiation therapy (EBRT) is used for In this article, the term “SRT” refers to five-fraction
unresectable, residual, or recurrent disease. Total doses stereotactic treatment and the term “HFRT” refers to 15
of 45 – 55 Gy are typically delivered with conventional fractions. Patients treated with HT received an average
fractionation. Conventional RT, hypofractionated RT of 50 and 55 Gy RT in 25 and 30 fractions (conventional
3
(HFRT), and stereotactic RT (SRT) options for EBRT schedule), respectively. Of the six patients treated with
have been described in the literature. At present, data CK, three patients received an average of 22 – 25 Gy in
8,9
on HFRT and SRT options using modern RT equipment five fractions; three patients received an average of 40 –
remain limited. This paper aims to share our limited but 42 Gy in 15 fractions as HFRT. The prescribed isodose line
long-term experiences with craniopharyngioma patients. (IDL) was between 71% and 80% in CK. For CK planning,

2. Materials and methods homogeneity and conformity indices for PTV were 1.16 –
1.41 and 1.11 – 1.39, respectively.
2.1. Patient characteristics
2.3. Ethical considerations
This is a single-institutional retrospective study. Patients
up to 30 years of age who had received post-operative or This study was conducted in adherence with the tenets
definitive RT following a diagnosis of craniopharyngioma of the Declaration of Helsinki. Informed consent was
were included in the trial. The data of the eight consecutive obtained from all participants. Ethical approval for the
patients with craniopharyngioma treated with RT in our study was given by the Institutional Ethics Committee with
radiation oncology department, Dr. Abdurrahman Yurtaslan approval number 2022-05/89 on May 12, 2022.
Ankara Oncology Training and Research Hospital radiation 2.4. Statistical analysis
oncology clinic between 2009 and 2019 were obtained from
or through the institutional electronic database, patient Analyses were performed using SPSS version 22. Median,
records, telephone calls, and face-to-face visits. mean, minimum, and maximum values were used as
descriptive variables. An analysis of overall survival (OS)
2.2. RT techniques and progression-free survival (PFS) was performed using
Six patients were treated with CyberKnife (CK) the Kaplan–Meier test. For PFS, death, local recurrence, or
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and two with Tomotherapy (HT) using the helical distant recurrence was considered an event.

Volume 2 Issue 2 (2024) 2 doi: 10.36922/arnm.3041