metastatic cancer is usually found in the bone , which is the third most common site of cancer metastasis .
metastatic bone cancer often occurs in the axial skeleton such as pelvis , ribs , skull , and vertebrae .
metastatic cancer of the limbs is frequently found at the proximal end of long bones such as the proximal end of the humerus and femurs .
metastatic cancer of the limbs inevitably causes pain , limb dysfunction and formation of a bump , or even results in pathological fracture .
these complications significantly influence the quality of life ( qol ) and affect the performance of adjunctive therapies , including chemotherapy and radiotherapy , which may further influence the survival time and the prognosis of these patients [ 46 ] .
non - surgical treatment is a major strategy for the treatment of multiple metastatic bone cancers of limbs , and , in addition to radiation ( external beam radiation , radiopharmaceuticals ) , adjunctive therapies include bisphosphonates and chemotherapeutic agents , ablative techniques ( radiofrequency ablation [ rfa ] and cryoablation ) , inhibitors of rank - rankl interaction ( eg , denosumab ) , hormonal therapies , and interventional techniques ( eg , kyphoplasty ) . for patients developing pathological fracture at the limbs , palliative surgical treatment is frequently adopted in which the lesions are removed completely , followed by filling of bone cement and fixation with plates and screws or intramedullary nails [ 911 ] .
these treatments may relieve the pain , but are less beneficial for the recovery of limb function , and weight - bearing walking is usually not possible using a crutch or a walker , so these patients often have poor qol [ 1214 ] . for patients with solitary metastatic bone cancer of the limbs , palliative surgical treatment is often clinically preferred . in the present study ,
solitary metastatic bone cancer of the limbs was treated according to the principles for the treatment of primary bone cancer . en bloc resection
was performed , followed by limb - salvage reconstruction of bone defects and limb function . to analyze the effectiveness of this strategy ,
the pain , qol , limb function , tumor - free survival and operative complications were evaluated .
from 2007 to 2010 , a total of 27 patients with solitary metastatic bone cancer were treated in our department , including 15 males and 12 females , with a mean age of 588.58 years ( range : 4375 years ) .
follow - up was carried out for 16.157.47 months ( range : 631 ) ( t=1.073 , p=0.294 ) .
the primary cancers included lung cancer in 7 patients , renal carcinoma in 6 , breast cancer in 5 , prostate cancer in 2 , endometrial carcinoma in 1 , thyroid cancer in 1 , colon cancer in 1 , rectal cancer in 1 , liver cancer in 1 , glioma in 1 , and gastric cancer in 1 patient .
metastatic bone cancer was detected 8~123 months ( mean : 42.2033.61 months ) after diagnosis of primary cancers in 20 patients , but metastatic bone cancer as the first sign facilitating the diagnosis of primary cancers was detected in 7 patients .
the cancer metastasis sites included the proximal end of the femur in 11 patients , proximal end of the humerus in 6 , middle part of the humerus in 3 , scapula in 2 , middle part of the femur in 2 , distal end of the femur in 1 , middle part of the ulna in 1 , and proximal end of the tibia in 1 patient .
the complaints included simple pain in 10 patients , pain and bump in 6 , and pathological fracture in 7 patients .
four patients had no complaints and metastatic bone cancer was identified by routine ect or pet .
limb - salvage surgery was performed in all patients according to the principles for the treatment of primary bone cancer .
artificial prosthetic replacement was performed in 21 patients , simple resection in 2 , reconstruction with allogeneic bones in 2 , inactivated bone replantation in 1 , and removal of hemi - cortex of the bone , filling of bone cerement , and internal fixation in 1 patient . in 7 patients , primary
cancer and metastatic bone cancer were identified simultaneously and then a one - stage operation was carried out for resection of primary cancer and metastatic cancer simultaneously . according to the enneking s staging system
, wide resection was done in 19 patients and marginal resection in 8 patients . in 21 patients , post - operative systemic chemotherapy and/or local radiotherapy
were performed , of whom 7 patients receiving marginal resection underwent local radiotherapy post - operatively .
qol and pain were evaluated before and after surgery in 21 patients . pain was assessed with the 10-point scale before and 1 month after surgery .
the qol was assessed with the sf-36 scale   before and 3 months after surgery .
post - operative limb function was evaluated with the american musculoskeletal tumor society ( msts ) system 3 months after surgery .
quantitative data with normal distribution were expressed as mean  standard deviation to describe the central tendency or discrete tendency .
the scores of pain , qol , and limb function were compared with the t test .
tumor - free survival was defined as the time from the end of surgery to the presence of new lesions .
from 2007 to 2010 , a total of 27 patients with solitary metastatic bone cancer were treated in our department , including 15 males and 12 females , with a mean age of 588.58 years ( range : 4375 years ) .
follow - up was carried out for 16.157.47 months ( range : 631 ) ( t=1.073 , p=0.294 ) .
the primary cancers included lung cancer in 7 patients , renal carcinoma in 6 , breast cancer in 5 , prostate cancer in 2 , endometrial carcinoma in 1 , thyroid cancer in 1 , colon cancer in 1 , rectal cancer in 1 , liver cancer in 1 , glioma in 1 , and gastric cancer in 1 patient .
metastatic bone cancer was detected 8~123 months ( mean : 42.2033.61 months ) after diagnosis of primary cancers in 20 patients , but metastatic bone cancer as the first sign facilitating the diagnosis of primary cancers was detected in 7 patients .
the cancer metastasis sites included the proximal end of the femur in 11 patients , proximal end of the humerus in 6 , middle part of the humerus in 3 , scapula in 2 , middle part of the femur in 2 , distal end of the femur in 1 , middle part of the ulna in 1 , and proximal end of the tibia in 1 patient .
the complaints included simple pain in 10 patients , pain and bump in 6 , and pathological fracture in 7 patients .
four patients had no complaints and metastatic bone cancer was identified by routine ect or pet .
limb - salvage surgery was performed in all patients according to the principles for the treatment of primary bone cancer .
artificial prosthetic replacement was performed in 21 patients , simple resection in 2 , reconstruction with allogeneic bones in 2 , inactivated bone replantation in 1 , and removal of hemi - cortex of the bone , filling of bone cerement , and internal fixation in 1 patient . in 7 patients , primary
cancer and metastatic bone cancer were identified simultaneously and then a one - stage operation was carried out for resection of primary cancer and metastatic cancer simultaneously . according to the enneking s staging system
, wide resection was done in 19 patients and marginal resection in 8 patients . in 21 patients , post - operative systemic chemotherapy and/or local radiotherapy
were performed , of whom 7 patients receiving marginal resection underwent local radiotherapy post - operatively .
the qol was assessed with the sf-36 scale   before and 3 months after surgery .
post - operative limb function was evaluated with the american musculoskeletal tumor society ( msts ) system 3 months after surgery .
quantitative data with normal distribution were expressed as mean  standard deviation to describe the central tendency or discrete tendency . the scores of pain , qol , and limb function were compared with the t test .
tumor - free survival was defined as the time from the end of surgery to the presence of new lesions .
all procedures were performed successfully , and no patient died during the follow - up period .
post - operative prosthesis dislocation occurred in 1 patient and closed reduction was successfully carried out .
deep venous thrombosis was found in 3 patients of whom inferior vena cava filter was placed in 2 and systemic anti - coagulation therapy done in 1 patient .
pulmonary infection was controlled following anti - infection therapy in 1 patient . as shown in table 2 , the score of pain was 6.853.11 and 1.260.81 before and 1 month after surgery , respectively , indicating that the post - operative pain was markedly improved ( t=9.978 , p<0.001 ) .
the qol score was 38.3013.05 and 65.7810.65 before and 3 months after surgery , respectively , revealing the quality of life was dramatically improved following surgery ( t=18.550 , p<0.001 ) .
the post - operative score of limb function ranged from 17 to 30 ( mean : 233 ) ( t=1.450 , p=0.016 ) .
activities of daily living recovered in all patients . for patients with metastatic bone cancer in lower limbs , they could walk with or without a walker . regarding cancer control ,
as shown in figure 1 , log rank testing revealed there was no significant difference in the tumor - free survival between patients receiving wide resection and marginal resection ( =0.121 , p=0.728 ) .
he was admitted due to pain and presence of pain and bump at the right hip for 2 months . on examination ,
a mass was found in the right lung and subsequent pathological examination revealed lung cancer .
radical resection for lung cancer and marginal resection of the bone cancer were performed ( figure 2 ) .
case 2 : male , 56 years old , prostate cancer concomitant with pathological fracture at proximal end of bilateral femurs . en bloc resection of the bone cancer and bilateral prosthetic replacement were performed ( figure 3 ) .
pathological fracture at the left humerus was found and subsequent pathological examination confirmed renal carcinoma . left radical nephrectomy and en bloc resection of cancer at the left humerus were performed , followed by artificial prosthetic replacement ( figure 4 ) .
case 17 : male , 62 year old , swelling and pain at left forearm 2 years after resection of rectal cancer .
implantation of inactivated bone and internal fixation with plates were performed after marginal resection of the bone cancer ( figure 5 ) .
all procedures were performed successfully , and no patient died during the follow - up period .
post - operative prosthesis dislocation occurred in 1 patient and closed reduction was successfully carried out .
deep venous thrombosis was found in 3 patients of whom inferior vena cava filter was placed in 2 and systemic anti - coagulation therapy done in 1 patient .
as shown in table 2 , the score of pain was 6.853.11 and 1.260.81 before and 1 month after surgery , respectively , indicating that the post - operative pain was markedly improved ( t=9.978 , p<0.001 ) .
the qol score was 38.3013.05 and 65.7810.65 before and 3 months after surgery , respectively , revealing the quality of life was dramatically improved following surgery ( t=18.550 , p<0.001 ) .
the post - operative score of limb function ranged from 17 to 30 ( mean : 233 ) ( t=1.450 , p=0.016 ) .
activities of daily living recovered in all patients . for patients with metastatic bone cancer in lower limbs
regarding cancer control , no local recurrence occurred in these 27 patients during the follow - up period .
as shown in figure 1 , log rank testing revealed there was no significant difference in the tumor - free survival between patients receiving wide resection and marginal resection ( =0.121 , p=0.728 ) .
he was admitted due to pain and presence of pain and bump at the right hip for 2 months . on examination ,
a mass was found in the right lung and subsequent pathological examination revealed lung cancer .
radical resection for lung cancer and marginal resection of the bone cancer were performed ( figure 2 ) .
case 2 : male , 56 years old , prostate cancer concomitant with pathological fracture at proximal end of bilateral femurs . en bloc resection of the bone cancer and bilateral prosthetic replacement were performed ( figure 3 ) .
pathological fracture at the left humerus was found and subsequent pathological examination confirmed renal carcinoma . left radical nephrectomy and en bloc resection of cancer at the left humerus were performed , followed by artificial prosthetic replacement ( figure 4 ) . case 17 : male , 62 year old , swelling and pain at left forearm 2 years after resection of rectal cancer .
implantation of inactivated bone and internal fixation with plates were performed after marginal resection of the bone cancer ( figure 5 ) .
the bone is the third most common site of cancer metastasis , following lung and liver .
in addition to the limbs , the spine is also a common site of cancer metastasis . in the present study
, we primarily focus on the surgical treatment of metastatic bone cancer of the limbs .
comprehensive therapy is preferred for the metastatic bone cancer , including surgical intervention , chemotherapy , radiotherapy and other conservative therapies .
metastatic bone cancer is a systemic disease , thus surgical therapy is usually performed on the basis of other adjunctive therapies .
the majority of metastatic bone cancers are predominantly derived from lung cancer and breast cancer , followed by renal carcinoma , thyroid cancer and prostate cancer [ 1820 ] .
metastatic bone cancer from lung cancer / renal carcinoma is usually characterized by osteolytic lesions , thus patients with this disease are susceptible to pathological fracture , and surgical intervention is required .
metastatic bone cancer from breast cancer / prostate cancer is usually osteogenic , especially in patients with prostate cancer .
when compared to patients with osteolytic lesions , those with osteogenic lesions seldom develop pathological fracture ; conservative therapy is often performed and surgical intervention less often required . in the present study , 1 patient with prostate cancer developed metastatic bone cancer and subsequent pathological fracture at the proximal end of bilateral femurs .
thus , for metastatic bone cancer patients with osteogenic lesions , the risk for pathological fracture should also be paid attention to , especially in those with intertrochanteric lesions .
patients with a mirels score of 9 are regarded to have high risk for fracture , and active prophylactic surgery is required . for patients developing pathological fracture , determination of surgical intervention is done based on the general conditions : tolerance to surgery , time from identification of primary disease to metastatic bone cancer , disease progression , expected survival time , extent of post - operative qol improvement , and post - operative limb function .
generally , surgical intervention should be considered for patients with favorable general condition , able to tolerate surgery , having no progression of primary disease , with expected survival time of longer than 6 months , and having poor qol due to pathological fracture .
once surgical intervention is determined for the treatment of pathological fracture , the requirements are similar to those in the treatment of primary bone cancer .
the reconstruction should be beneficial for the rapid recovery of limb function or partial load - bearing .
usually , artificial prosthetic replacement is performed in patients with lesions near the joint ; implantation of allogeneic bone or inactivated cancer - bearing bone , followed by internal fixation with plates , is recommended for patients with lesions at the bone shaft or non - weight - bearing site . in the present study ,
lesions were mainly found at the site near the joint , and thus artificial prosthetic replacement was the major strategy for the treatment ; the post - operative limb function was markedly improved . for pathological fracture , surgical treatment aims to relieve the pain and improve the qol and limb function . in the present study
results demonstrate that post - operative pain , qol , and limb function were dramatically improved .
however , for patients with multiple bone metastases , surgical intervention is unable to achieve wide resection or resection of foci , and is usually highly invasive . under this condition , patients usually have high surgical risk .
wide resection was performed in the majority of patients and a minority of patients received marginal resection .
post - operative local radiotherapy was also carried out as an adjunctive therapy , achieving favorable control of local tumors .
in addition , statistical analysis showed there was no significant difference in the tumor - free survival time between patients receiving wide vs. marginal resection .
this demonstrates that only systemic treatment is an effective strategy to improve the survival of cancer patients .
nevertheless , the wide or marginal resection of the cancer plays an important role in the control of local cancer and pain , and improvement of qol and limb function . in our study ,
metastatic bone cancer was the first sign in 7 patients and further examinations identified primary diseases .
of these patients , 6 received 1-stage resection of primary cancer and metastatic bone cancer simultaneously .
the remaining patient had prostate cancer and pathological fracture at the proximal end of the bilateral femurs .
bilateral lesions were resectable and treatment was similar to that in patients with solitary metastatic bone cancer .
one - stage resection of lesions at bilateral femurs was performed , followed by joint replacement , and endocrine therapy was done as a treatment for primary prostate cancer . for patients with resectable primary and metastatic lesions
, post - operative chemotherapy and/or radiotherapy is recommended , which may significantly delay disease progression in the tumor - free survival time , elevate survival rate and improve qol .
this should be done in the presence of completely resectable primary and metastatic lesions . for these patients , resection of a single lesion may pronouncedly affect the effectiveness of adjunctive therapy and survival of cancer - bearing patients .
for patients with solitary metastatic bone cancer of the limbs , limb salvage surgery with wide or marginal resection is beneficial for the improvement of post - operative pain , qol and limb function .
in addition , the control of local cancer is also favorable and the local recurrence rate not influenced . for patients with metastatic bone cancer with concomitant primary cancer , 1-stage resection of both lesions is recommended , which may delay disease progression and improve the survival rate . in our study ,
the time of follow - up was relatively short , and the effect of limb salvage surgery on the overall survival needs to be further investigated in studies with long - term follow - up .
 summarybackgroundto evaluate the pain , quality of life ( qol ) , and limb function of patients after en bloc resection of solitary metastatic bone cancer in the limbs.material/methodsa total of 27 patients with solitary metastatic bone cancer in the limbs were recruited . 
 all these patients underwent limb - salvage surgery with en bloc resection of the metastatic tumor . 
 pain and qol were evaluated before and after surgery . 
 pain was assessed with a 10-point scale before and 1 month after surgery . 
 the qol was evaluated with the sf-30 scale before and 3 months after surgery . 
 limb function was evaluated with the musculoskeletal tumor society scale ( msts ) 3 months after surgery . 
 follow - up was performed for 6~31 months ( mean : 16.157.47 months).resultsall procedures were successfully performed . 
 post - operative complications were found in 6 patients , including incision infection , prosthesis dislocation , deep vein thrombosis , and pulmonary infection . the pain score before and 1 month after surgery was 6.853.11 and 1.260.81 , respectively , indicating obvious improvement ( t=9.978 , p<0.001 ) . the qol score before and 3 months after surgery was 38.3013.05 and 65.7810.65 , respectively , indicating pronounced improvement ( t=18.550 , p<0.001 ) . 
 the mean post - operative msts score was 233 ( range : 1730 ) ( t=1.450 , p=0.016 ) . 
 no local recurrence was observed in any patient during the follow-up.conclusionslimb salvage surgery with wide or marginal resection for solitary metastatic bone cancer may significantly improve the pain , qol , and limb function , but there is no difference in local control between wide and marginal resection . 
Background
Material and Methods
General data
Surgical procedures
Post-operative evaluation
Statistical analysis
Results
Postoperative complications
Evaluation of pain, QOL and limb function
Local recurrence
Representative cases
Discussion
Conclusions