giant cell tumor ( gct ) accounts for about 7 to 10% of all cases of primary spinal tumors .
patients with gct are usually diagnosed in the third or fourth decade of life , and there is a slight female preponderance152325 ) .
gct usually occurs in the metaepiphyseal ends of the long bone , and it rarely occurs in the spine2611 ) .
savini et al.28 ) reported that only 2.9% of all gct incidences occur in the spine , and goldenberg et al.14 ) reported that spine involvement is 1.3% in a study of 218 cases of gct .
a research conducted by mayo clinic reported incidence of up to 6.5% of gct in the spine27 ) .
gct in the spine usually involves sacrum , but it also occurs in other parts of the spine .
gct is classified as benign tumor histopathologically , but it had a locally aggressive tendency . and , if it is incompletely excised , it shows a high recurrence rate .
there is a reason for a relatively worse prognosis in gct patients , compared to other benign primary spinal tumor patients7826 ) .
many studies reported from 10 to 40% local recurrence rate after spinal gct treatment , depending on surgical protocols46141821 ) . in case of recurrence
, excision is conducted when another operation is possible . if re - operation is considered difficult , radiation therapy ( rt ) is introduced . generally ,
however , due to the characteristics of spine , there is a possibility of neural or vascular injury , which will result in difficult wide en bloc excision10 ) .
some authors reported that rt is not effective in local tumor control and has a risk of malignant transformation of gct15252728 ) .
recent studies reported chemotherapy as effective in case of recurrence or when there are complications1591329 ) .
the objective of this study is to obtain the results of treatment gct in the spine .
in addition , we analyzed whether local recurrence is influenced by surgical protocols , or rt .
the subjects of our study were 242 patients treated for gct from 2000 to 2012 . patients with involved gct spine were 19 cases , and incidence rate was 7.9% .
the median age at their first diagnosis was 31 years ( range , 14 to 39 years ) .
fourteen tumors were located in the sacrum , one in cervical , one in thoracic , and three in lumbar spine .
all the lesions were single and localized at the original spine except one , which originated in the sacrum extending into the coccyx .
the median follow - up period was 92 months ( range , 18 to 163 months ) .
main symptom of the patients with gct was pain , and the average visual analogue scale ( vas ) was 7 ( range , 5 to 9 ) .
only one out of 19 showed motor weakness initially caused by spinal cord compression at thoracic spine . for initial treatment ,
6 out of 19 patients underwent gross total removal ( gtr ) , and 13 patients underwent subtotal removal ( str ) .
adjuvant rt was performed in 12 cases , 2 cases in gtr group and 10 cases in str group .
we analyzed the recurrence rate and recurrence free period ( rfp ) for gct in the spine after the treatment .
in addition , we analyzed the difference of the recurrence rate according to the surgical protocol and rt .
we did not consider the effect of the treatment for the patients with recurrence after the initial treatment .
chi - square tests were used for categorical variables , and student 's t - tests were used for continuous and ordinal variables , as appropriately . a p value 0.05 ( two - tailed )
the data were compiled and analyzed with the software package spss , version 18.0 ( spss inc . , chicago , il , usa ) .
during the follow - up period , 7 out of 19 patients had local recurrence , at 36.8% rate .
an average recurrence free period was 14 months ( range , 4 to 34 months ) for the patients with recurrence .
median recurrence free period of all patients was 84 months ( 95% ci , from 4 to 163 months ) ( fig .
gtr group did not have any recurring patients , while 7 out of 13 patients who received str had local recurrence ( table 2 ) , which is statistically significant ( p=0.024 ) .
this implies that gtr is the most important method of treatment for controlling the tumor .
as for the local control effect of radiation therapy , the average recurrence free period of the group that underwent radiation therapy was 112 months ( 95% ci , from 74 to 150 months ) , which was longer than that of the group without radiation therapy , for 65 months ( 95% ci , from 47 to 83 months ) ( fig .
because there was a statistically significant difference between rt group and non - rt group ( p=0.041 ) , we considered that radiation may be effective in local control of tumors .
four patients underwent re - operation , 2 patients underwent re - operation and rt , and 1 patient underwent radiosurgery .
gtr was possible in only one out of 6 patients who underwent re - operation .
all patients reported relieved pain after the treatment according to vas ( range , 0 to 5 ) .
nine out of 19 patients were pain - free during the follow - up period .
the patient with motor weakness showed incomplete recovery after surgery , although the improvement was not functional and bladder dysfunction remained .
neurological complication after surgery occurred in 3 out of 19 patients , including bladder or bowel dysfunctions .
all the patients who experienced complications had gct in the sacrum . until the final follow - up period
, 18 out of 19 patients remained alive without recurrence , and 1 patient with pulmonary metastasis expired due to pulmonary complication .
female 31-year - old patient visited our hospital with pain in buttock that lasted for 4 months . magnetic resonance ( mr )
the patient underwent str , and the pathologic examination revealed to be gct . on computed tomography scan ( ct ) after the operation showed remnant tumor on the ventral side of s2 spinal canal ( fig .
four months after the initial operation , mr image showed the progression of the tumor extending to the left side ( fig .
ninety - four months after re - operation , the tumor did not recur ( fig .
33-year - old male patient complained lower back pain and radiating pain into both legs for 4 months .
sunnyvale , ca , usa ) radiosurgery was done to the remnant tumor located in front of the sacrum ( fig .
the patient 's pain was relieved and he has been stable for 68 months ( fig .
female 31-year - old patient visited our hospital with pain in buttock that lasted for 4 months . magnetic resonance ( mr )
the patient underwent str , and the pathologic examination revealed to be gct . on computed tomography scan ( ct ) after the operation showed remnant tumor on the ventral side of s2 spinal canal ( fig .
four months after the initial operation , mr image showed the progression of the tumor extending to the left side ( fig .
ninety - four months after re - operation , the tumor did not recur ( fig .
33-year - old male patient complained lower back pain and radiating pain into both legs for 4 months .
sunnyvale , ca , usa ) radiosurgery was done to the remnant tumor located in front of the sacrum ( fig .
the patient 's pain was relieved and he has been stable for 68 months ( fig .
female 31-year - old patient visited our hospital with pain in buttock that lasted for 4 months . magnetic resonance ( mr ) image showed a huge enhancing mass involving the sacrum ( fig .
the patient underwent str , and the pathologic examination revealed to be gct . on computed tomography scan ( ct ) after the operation showed remnant tumor on the ventral side of s2 spinal canal ( fig .
four months after the initial operation , mr image showed the progression of the tumor extending to the left side ( fig .
ninety - four months after re - operation , the tumor did not recur ( fig .
33-year - old male patient complained lower back pain and radiating pain into both legs for 4 months .
sunnyvale , ca , usa ) radiosurgery was done to the remnant tumor located in front of the sacrum ( fig .
the patient 's pain was relieved and he has been stable for 68 months ( fig .
the gct usually involves the end of long bone as femur ( 23% ) , tibia ( 21% ) , and fibula ( 5% ) around knee , and a few other arise from the spine ( range , 3% to 7%)24 ) .
it is reported that there is a slight female preponderance in spinal gct152325 ) . in our study , the incidence of spinal gct was 7.9% , and the male to female ratio is 1 to 0.9 .
however , gct in the spine is not easy to remove totally because of lack of accessibility and adjacent important neural and vascular structures10 ) . in case of incomplete excision
, rt can be considered , but rt for gct is still controversial1516252728 ) . wide or marginal excision of the tumor or en bloc resections may yield in a lower recurrence rate .
liljenqvist et al.20 ) stated on malignant tumors of the spine that en bloc spondylectomy enables wide or marginal resection in most cases with acceptable morbidity .
compared to a degree of resection , the textbook showed average of 50% ( from 35 to 70% ) in curettage alone and from 10 to 15% recurrence rate in en bloc resection24 ) .
campanacci et al.6 ) reported a recurrence rate of 27% after intralesional curettage versus rates of 8% and 0% after marginal or wide resection , respectively .
fidler reported successful result of only one recurrence in 9 consecutive patients who underwent en bloc resection12 ) . in a larger series , 10 of 32 patients who had intralesional curettage recurred within 16 months postoperatively and none of 2 patients with en bloc resection recurred15 ) .
regardless of its surgical resection , 25 to 28% of recurrence rate showed in other series152728 ) . according to kim et al.16 ) , 32.4% of recurrence rate in curettage and 11.1% of rate in en bloc resection ( overall 27.1% ) was16 ) . in our study , gtr was defined as cases in which all the involved structures were removed completely .
average recurrence rate of all patients was 36.8% , with 0% recurrence rate in gtr group , and 53.8% in str group .
the surgical protocols showed a statistically significant difference ( p=0.024 ) , implying gross total resection as more desirable .
we performed gtr rather than en bloc wide excision but there was no recurrence case during the median follow up period 92 months .
in addition , 14 out of 19 cases located in the sacrum . en bloc resection of the sacrum is much more complicated than that of the thoracolumbar spine .
most report about en bloc spondylectomy for gct mentioned above localized in the thoracolumbar spine . in case of the recurrence ( case 4 ) , the patient received additional surgery and rt .
considering the morbidity of en bloc wide excision in spinal gct , grt is not worse than en bloc wide excision . in the early 2000s
, str and rt was used to treat spinal gct in our hospital , which was the reason for high recurrence rate .
later , str was considered not effective for local control of gct , which led to a wider use of gtr .
however , recent studies insisted that rt is not only a useful adjuvant treatment modality after incomplete removal of tumors but also an effective therapy as a sole treatment of gct of the spine15252728 ) .
hart et al.15 ) reported that 8 out of 36 patients received rt as an initial treatment before surgery , no case except one recurred .
four patients had rt after recurrence , and only 1 patient experienced re - recurrence .
kim et al.16 ) reported that regardless of surgical protocols , 29 out of 96 cases had received rt and only 3 cases ( 10.3% ) of recurrence occurred . in 67 cases without rt , 23 cases ( 34.3% ) of recurrence occurred , which is significant statistically ( p=0.031)16 ) . in our study , although recurrence rate was 42% after rt , average recurrence free period was 112 months for rt group , and 65 months for non - rt group , with statistical significance ( p=0.041 ) .
even after recurrence , additional rt or radiosurgery after re - operation yielded good results .
rt seems to be a good treatment modality for delaying recurrence and locally controlling the tumor .
distant metastasis of gct is reported to be about 2 to 9%17 ) . in our study , only 1 out of 19 patients ( 5% ) had pulmonary metastasis .
bertoni et al.3 ) mentioned that rt or chemotherapy may be useful to treat pulmonary metastasis of gct .
other adjuvant therapies , such as a cryotherapy that had cure rate 92% in marcove 's first series and a preoperative embolization that was performed in five patients with result of no recurrence , were mentioned in these series . however a relatively large number of patients is not studied yet22 ) .
lee et al.19 ) reported that bone cement injection offers an adjuvant strategy that may enhance the efficacy of treatment for gct when complete en bloc spondylectomy is difficult .
balke et al.1 ) mentioned that most inoperable sacral gcts that had repeatedly recurred did not increase in size with no further recurrence was seen .
although the role of bisphosphonates for treatment of gct is still unknown , the administration of bisphosphonates can be considered in complicated cases and metastasis .
thomas et al.29 ) reported that 35 patients of gct were treated with denosumab , 30 cases were effective for tumor control after 25 weeks . in branstetter et al.5 ) study , 17 out of 20 patients were examined at various stages of treatment to distinguish clinical benefits from denosumab such as improved functional status or reduced pain .
gct in the spine is difficult to resect completely due to the special structure of the spine and the invasive nature of the tumor .
bloc wide excision is a well known a treatment of choice in order to manage gcts .
however , en bloc wide excision of the gct in the spine is not easy without damaging neurovascular structures .
the authors performed gross total removal rather than en bloc wide excision and obtained results . in case of str , rt was beneficial in delaying tumor recurrence .
 objectivethe treatment of giant cell tumor ( gct ) is mainly performed surgically . 
 however , gct in spine seems difficult to treat because of the limited surgical accessibility and proximity . in this report 
 , we analyzed the outcome of gct treatment in spine.methodsbetween 2000 and 2012 , 19 patients received treatment for gct in spine . 
 median age at their first diagnosis was 31 years , 10 patients were male , and 9 female . 
 fourteen tumors were located in the sacrum , 1 in cervical , 1 in thoracic and 3 in lumbar spine . as primary treatment , gross total removal ( gtr ) was done in 6 patients , and subtotal removal ( str ) in 13 patients . 
 radiation therapy ( rt ) as an adjuvant therapy was performed in 2 cases in gtr group and 10 cases in str group.resultsduring the follow - up , 7 patients had local recurrence ( 36.8% ) . 
 the average period until recurrence after primary treatment was 14 months . 
 no recurrence was detected in gtr group . 
 recurrence was noted in 7 out of 13 patients who underwent str . 
 these differences were statistically significant ( p=0.024 ) . 
 a median of recurrence free period ( rfp ) was 84 months . 
 also average rfp of the rt group was 112 months , and non - rt group was 65 months . 
 these differences were statistically significant ( p=0.041).conclusiontreatment of choice for gct in spine is a complete removal of tumor without neurological deficits . in case of incomplete removal , radiation therapy may be a useful adjuvant treatment modality . 
INTRODUCTION
MATERIALS AND METHODS
RESULTS
Case presentation
Case 1
Case 2
DISCUSSION
CONCLUSION