Page 43 - ARNM-2-2

Advances in Radiotherapy
& Nuclear Medicine Hypofractionated radiotherapy in craniopharyngioma

34%, and 40% patients, respectively. In our study, visual The strategy for treatment should be determined while
and neurological functions of the included patients were considering the possibility of tumor recurrence even
not negatively affected, and we found that one patient’s use after achieving GTR. In addition, performing surgery
5,15
of endocrine medication increased slightly and another for craniopharyngioma necessitates significant technical
patient continued to gain weight. The higher 5-year experience. According to one of the largest surgical series,
PFS rate in our study, compared to the referenced study 95.6% of craniopharyngiomas with a diameter between
(85.7% vs. 78%), may be attributed to the use of modern 3 and 6 cm were totally resected, while only 58.8% of
imaging methods in all patients. The study also revealed tumors with a diameter larger than 6 cm were completely
that OS- and event-free survival did not reach a plateau removed. 16
before 9 years, likely due to late relapses. As our study had Craniopharyngioma has a high recurrence rate 17,18
a median follow-up period of only 6 years, we were unable when complete resection is not achievable. Therefore,
to obtain information on longer-term survival rates. In RT is preferred after partial resection due to the local
3
the study by Regine et al., which evaluated the long-term aggressive behavior of craniopharyngioma. In their study
results of craniopharyngioma management, a noticeable on the surgical results of craniopharyngioma, Shi et al.
increase in local control at doses of 55 Gy and above was found that out of 167 patients who underwent total tumor
noted. The authors suggested keeping the conventional removal, 23 (13.7%) experienced tumor recurrence within
dose above 55 Gy. Furthermore, it has been reported that an average of 1.8 years. In contrast, out of 32 patients
16
treatment-related complications increase significantly at who underwent subtotal or partial resection, 24 (75%)
doses of 61 Gy and above. For the cases included in this experienced recurrence within an average of 0.5 years. The
13
study, since the tumor was always adjacent to the optic mean follow-up time for the 204 patients was 2.1 years,
chiasm, we administered doses that the optic pathways raising the question of whether the recurrence rate could
could tolerate, with the hope that full vision and existing be higher with longer follow-up periods. In addition, the
endocrine functions can be preserved to a large extent.
study reported a mortality rate of 3.9% within 1 month after
There is currently no consensus regarding the standard surgery, which is an improvement compared to previous
treatment for craniopharyngioma. A recent study by surgical series. 17-21 It is worth noting that no patients were
Zhang et al., which analyzed 1218 craniopharyngioma lost to follow-up in the early period after RT in our study.
14
patients, found no significant difference in OS or cause- The treatment for craniopharyngioma can result in
specific death rates between patients who received only
RT, those who underwent subtotal resection (STR) plus complications that fall into four categories: pituitary,
hypothalamic, visual, and general neurosurgical.
22
RT, or those who underwent gross total resection (GTR) Therefore, the most anticipated side effects of treatment
plus RT. In addition, the study found that only RT was are headache, visual, somatic, cognitive, and endocrine
superior, in terms of survival, to subtotal resection. Despite system problems resulting from the tumor’s location. If the
being the ideal outcome for surgery, complete resection craniopharyngioma is located near functional structures
is difficult to achieve in many cases due to the proximity such as the optic pathway, it is treated with fractionated
of the lesion to critical structures such as optic pathway,
hypothalamus, and pituitary gland. In a retrospective study SRT or other RT methods to prevent the side effects
12
conducted by Tsugawa et al., 20.2% out of the 242 patients of aggressive surgery. A study conducted at Princess
7
included underwent GTR as the first operation, 75.2% Margaret Hospital found that 53 patients who received
underwent partial resection, 4.5% had biopsy only, and 50 Gy in 25 fractions, either postoperatively or as salvage
RT, had a higher incidence of new endocrinopathies and
29.8% of the patients required multiple operations before visual dysfunction after surgery alone than after RT. The
23
RT with Gamma Knife was applied. In our patient cohort, present study did not identify any chronic side effects,
before RT, only 1 patient (12.5%) achieved GTR, 1 patient
(12.5%) was inoperable, 6 patients (75%) had undergone except for a slight increase in hormone doses in one patient
partial resection, and 3 patients had undergone 2 or more and continued weight gain in another patient after RT.
operations (37.5%). The patient who underwent GTR had There were no reported decreases in vision, and in fact,
a recurrence 1 year after the first operation, before RT. improvement was observed in two patients. However, it is
Therefore, all patients in the current study had gross disease important to note that one of these patients passed away
nd
7
before EBRT. In Tsugawa et al.’s study on SRT, the 5-year in the 2 year after receiving RT (40 Gy/15 fractions, CK)
OS and PFS rates were 92.5% and 62.2%, respectively. In without tumor.
our study, the OS and PFS rates for 5 years were both 85.7%. Cysts are also reported to have regrown during the
All eight of our patients were progression-free at the end of several weeks of fractionated RT. One of our patients’
24
the follow-up period, and only one death occurred. tumor’s cystic components regrew within a month after

Volume 2 Issue 2 (2024) 6 doi: 10.36922/arnm.3041