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post - operative chemotherapy has shown the benefit in the cases of residual disease after initial surgery and metastatic disease in the literature . we have presented the case of a 70-days old male child with primary infantile fibrosarcoma of the left lung and distant metastasis of skull .
the aim of this publication was to highlight the role of adjuvant chemotherapy to improve outcome of infantile fibrosarcoma with residual tumor and / or metastatic disease .
fibrosarcoma has shown as heterogenous group of malignant mesenchymal origin tumor that has classified as non - rhabdomyosarcoma soft tissue sarcoma ( nrsts ) ( 1 - 5 ) .
fibrosarcoma has accounted for about 5% of pediatric nrsts and for approximately 25% to 30% of soft tissue malignancies in children younger than 1 year ( 6 , 7 ) . according to the pog staging system for nrsts ,
a fibrosarcoma has considered infantile fibrosarcoma ( ifs ) if it has occurred in 4 years old children or younger ( 8) .
because fibrosarcoma in young children was considerably less aggressive and most curable than the elder children , it has labeled " infantile fibrosarcoma " ( ifs ) ( 1 - 6 ) .
fibrosarcoma most commonly has presented at the extremities , trunk , and head / neck ( 9 ) .
primary pulmonary fibrosarcoma was extremely rare lung neoplasm that has accounted for about 12% of all pulmonary tumors in infants and young children ( 10 ) .
fibrosarcoma of the lung could arise from the trachea , bronchus , pulmonary parenchyma or pulmonary artery ( 10 ) .
pulmonary fibrosarcoma has diagnosed , following ruling out more common causes of lung masses , such as bronchogenic cyst , adenomatoid malfunction , and sequestration of the lung through clinical findings and imaging studies .
our case was a 70-days old male child that has presented with respiratory distress and cyanosis following breastfeeding .
the patient has admitted with initial diagnosis of pneumonia and subsequently an antibiotic therapy has initiated .
a chest radiography has shown an opacity in the lower part of the left lung .
a computerized tomography ( ct ) of the thorax has revealed a well - defined heterogeneously enhancing mass measuring 45 mm  40 mm in the lower lobe of the left lung ( figure 1a and 1b ) .
differential diagnoses has proposed by radiological service has included pulmonary sequestration and congenital adenomatoid malformation .
the exploration has revealed a mass measuring 50 mm  40 mm  20 mm , involving the lower lobe of the left lung , having a solid appearance .
after installing chest tube , infant has supported through mechanical ventilation during the post - operative period and has discharged from pediatric intensive care unit after 4 days with no further problems with respiratory distress .
macroscopic examination has consisted of a lung lob measuring 50  40  20 mm .
cross - section shown a gray - white well circumscribed soft to firm mass with irregular brown border .
histological examination of tissue sections has revealed proliferation of neoplastic cells in lung tissue ( figure 2 ) .
there was atypical proliferation of spindled to fusiform cells have arranged in interlacing long fascicules .
the neoplastic cells has shown little pleomorphism , scanty cytoplasm with indistinct cell borders and have separated by interwoven collagen fibers and have arranged in a parallel fashion .
the tumor cells were positive for vimentin but non - reactive for cytokeratin , s-100 protein , a smooth muscle actin , and desmin .
metastatic workups including radionuclide bone scan and skull ct examinations have taken after initial surgery .
increased skeletal has up taken of the skull bones have detected by ( tc)-99m - labeled methylene diphosphonate ( mdp ) ( figure 3a ) .
skull ct examinations have revealed bone lesions without brain parenchymal disease ( figure 3b ) .
there was a residual tumor measuring 5  7 mm dimensions on subsequent chest ct scan after surgery .
post - operation adjuvant chemotherapy has planned to treat residual disease and distant bone metastasis .
chemotherapy regimen has included ( va : vincristine 0.025 mg / kg day 1 ; actinomycin d 7.5 g / kg days 1 - 5 ) .
he has received 12 cycles of va regimen supported with granulocyte colony - stimulating factor ( g - csf ) .
the infant has routinely assessed for liver , renal , cardiac and pulmonary functions through physical examination and laboratory investigations during the chemotherapy treatment . after completing 12 cycles of va regimen
, there was no any sign of residual tumor on ct of the thorax . during the follow - up ,
fdg - active metastatic lesion was normal on fdg - pet imaging after 12 cycles of va regimen .
he has grown up as a 21-months old boy without any sign of recurrence by radiological and physical examinations and has been off therapy since 18 months . during this time
ifs has more seen among infants younger than two years of age ( 11 ) . according to existing information , ifs has rather affected limbs ( especially the distal part ) , trunk ( including shoulder and pelvic girdles ) and head and neck ( 12 - 17 ) . in histological terms , ifs was similar to the adult type , but clinical presentations of the disease in these two age groups had obvious differences ( 18 , 19 ) .
furthermore , in genetic terms , ifs has characterized by chromosomal translocation ( 15 , 18 ) ( p13 , q25 ) , which has led to etv6-ntrk3 fusion gene ( 20 , 21 ) .
prognosis and long - term survival has much better in ifs compared to adults ( 1 , 6 , 18 , 19 ) .
the main treatment of fibrosarcoma has involved complete surgical resection of tumor ( 11 - 15 , 22 - 25 ) possibility of complete resection of the tumor has increased chances of recovery and non - recurrence of disease . however , it was not always possible to perform complete resection , like masses in head and neck , or metastatic development of primary disease when using chemotherapy , before or after biopsy or tumor resection , which led increasing recovery and survival rates ( 22 - 29 ) .
currently , there were several reports in the literature on the effective role of adjuvant chemotherapy after tumor resection in the treatment of infantile fibrosarcoma ( table 2 ) .  
abbreviations : m , male ; f , female ; c , cure ; r , relapse ; d , dead ; l , limb ; t , trunk ; r - p , retro - peritoneal ; h , head ; n , neck .
( 13 ) on 40 patients with ifs , recurrence of disease was 37.5% . in this report , only surgery and radiotherapy have used in treatment of the patients .
loh et al . ( 23 ) has reported , based on dana farber cancer institute results , use of adjuvant chemotherapy has increased cure rate in infants with fibrosarcoma .
orbach et al . ( 24 ) has reported a retrospective analytical study on the outcome of ifs treatment in europe between 1979 and 2005 , of the 56 patients , 34 ( 60.7% ) have received adjuvant chemotherapy , and recurrence rate was 18% .
inthis analytical study , use of chemotherapy has improved outcome of the patients . in the other reports , use of adjuvant chemotherapy has also led to increased cure rate in infants with fibrosarcoma ( 25 - 30 ) . in mayo clinic report , of the 27 patients have operated , 4 underwent amputation ( 13 ) . as highlighted by orbach , ( 24 ) and kupeli ( 28 ) reduced amputation rate with preoperative chemotherapy , have followed by delayed surgery clearly has shown positive role of chemotherapy .
few reports have been published on primary pulmonary fibrosarcoma ( 31 - 34 ) . in most of these reports ,
surgery was the first line of treatment , and in cases where complete tumor resection was not possible or in presence of distant metastasis , use of adjuvant chemotherapy has increased long - term survival of patients .   in the most published reports ,
chemotherapy regimens have included vincristine and actinomycin d , with or without cyclophosphamide ( 22 - 25 ) .
chemotherapy regimens that have included doxorubicin , ifosfamide , and etoposide have also been used , although these drugs might be more toxic , particularly to young children .
savas et al . ( 31 ) has reported a 12-year - old boy with primary bronchopulmonaryfibrosarcoma .
successful treatment has achieved with surgical resection of the tumor followed by adjuvant chemotherapy and radiotherapy .
picard et al . ( 32 ) , has reported an eight - year - old boy with primary endobronchialfibrosarcoma .
he has received preoperative chemotherapy , followed by delayed complete tumor resection . in the two - year follow - up , no sign of recurrence has observed .
( 33 ) has reported a one - day - old male infant with congenital pulmonary fibrosarcoma . he has presented with respiratory distress and radiographic opacity in the middle part of the right lung .
( 34 ) has reported 5 cases of bronchopulmonaryfibrosarcoma in newborns and children up to 11 years of age at diagnosis .
after complete tumor resection in 4 cases , and in 4 - 9 years follow - up , no sign of recurrence has observed .
primary pulmonary fibrosarcoma would be an extremely rare tumor of lung in the pediatric age group .
in radiological terms , it was in the form of a fine mass , or lobule , and could not be differentiated from other more common pulmonary masses .
use of post - operation adjuvant chemotherapy in the cases of infantile fibrosarcoma could improve long - term survival especially in presence of residual tumor after surgery and metastatic disease .
introduction : pulmonary fibrosarcoma has been an extremely rare tumor in children . 
 wide surgical resection of infantile fibrosarcoma would be the treatment of choice.case presentation : post - operative chemotherapy has shown the benefit in the cases of residual disease after initial surgery and metastatic disease in the literature . 
 we have presented the case of a 70-days old male child with primary infantile fibrosarcoma of the left lung and distant metastasis of skull.conclusions:the aim of this publication was to highlight the role of adjuvant chemotherapy to improve outcome of infantile fibrosarcoma with residual tumor and / or metastatic disease .