mesenchymal breast neoplasms are rare . sarcoma is a heterogeneous neoplasm arising from mesenchymal cells .
breast sarcomas are rare neoplasms derived from non- epithelial elements of the gland and represent < 1% of all breast cancers   estimated as 45 new cases per 10 million women .
most cases of breast sarcoma are secondary to radiotherapy due to increasing use of breast radiation after breast - conserving treatment . about 1 of 300 patients receiving radiotherapy for breast cancer can be expected to develop sarcoma .
only a few hundred cases of breast sarcomas have been reported in the literature making the diagnosis difficult .
we present a rare case of lymphatic metastases of primary spindle cell sarcoma of the breast .
forty - three per cent occur in the extremities with two - thirds of them in the lower limb and one - third in the upper limb .
thirty - four per cent of sarcomas are intra - abdominal consisting of 19% visceral and 15% retroperitoneal lesions .
several histological subtypes of breast sarcomas have been described as case series or case reports due to the multiple different cells present in the mesenchymal tissue of the mammary gland , such as endothelial , muscle and fat cells . the most common subtypes are malignant fibrohistiocytoma , fibrosarcoma , angiosarcoma and spindle cell sarcoma .
less common subtypes are liposarcoma , leiomyosarcoma , rhabdomyosarcoma , osteosarcoma , synovial sarcoma , neurosarcoma , stromal sarcoma , chondrosarcoma and hemangiopericytoma .
angiosarcomas appear to be the commonest histological subtype in radiation - induced sarcomas of the breast [ 4 , 5 ] .
the main risk factor for the development of breast sarcomas is previous radiation treatment for breast carcinoma and non - hodgkin 's lymphoma .
other recognized factors are chronic lymphoedema , exposure to vinyl chloride and artificial implants   as well as li - fraumeni syndrome through a p53 mutation .
a 45-year - old healthy caucasian female patient presented in the emergency department with sudden onset of left breast erythema . on examination , she had an oedematous , tender , erythematous left breast with areas of blistering , epidermolysis and necrosis .
an ultrasound scan revealed the presence of gas and fluid - filled pockets . the laboratory risk indicator for necrotising fasciitis score
can be utilized to risk stratify patients presenting with signs of cellulitis to determine the likelihood of necrotizing fasciitis .
a score > 6 of 13 indicates that necrotizing fasciitis should be seriously considered . in this case , a score of 8 was allocated for serum sodium of 126 mmol / l , haemoglobin of 6.6 g / dl and c - reactive protein of 306.7 mg / l .
her other biochemical markers were normal , including serum creatinine of 68 mol / l , plasma glucose of 8.8 mmol / l and a leukocyte count of 11.5  10/l .
a provisional diagnosis of necrotizing fasciitis was made , and the patient was referred to the breast surgeons .
the histopathology demonstrated that the breast was partially replaced by a partly cystic and partly solid necrotic lesion .
a microscopic examination showed an atypical undifferentiated spindle cell lesion with a fascicular architecture , pleomorphism and marked mitotic activity with areas of ulceration and necrosis ( figs  1 and 2 ) .
the initial set of immunostains performed showed that tumour cells were negative for cytokeratins ( fig . 
3 ) , s100 and lca . the tumour cells showed diffuse and strong vimentin positivity ( fig . 
further immunocytochemical labelling showed weak expression of cd99 , patchy strong expression of cd10 and patchy weak expression of smooth muscle actin .
cytokeratins ( cam 5.2 ) and ema were expressed and there was no tumour - specific expression of cd34 , desmin or myogenin .
fluorescent in - situ hybridization analysis failed to demonstrate evidence of a t(x:18 ) translocation using the lys - syt break apart probe .
the diagnosis of a grade 3 undifferentiated spindle cell sarcoma was made and although the tumour was reported to have a clear resection margin ( 5 mm ) in most areas , the presence of necrosis and granulation tissue reaching the deep margin made the status of the margin uncertain . 

figure  1:photomicrograph 4 h&e ; spindle cell tumour with areas of haemorrhage and necrosis . 

figure  2:photomicrograph 40 h&e ; pleomorphic spindle cells in fascicles with several mitoses . 

computed tomography scan demonstrated left axillary lymphadenopathy and a small left - sided basal effusion . following discussion of the case at the multidisciplinary meeting , radical completion mastectomy was recommended .
reconstruction was with a split thickness skin graft by the plastic surgery team prior to her radiotherapy treatment ( fig . 
necrotizing fasciitis is a highly lethal infection that causes rapidly spreading necrosis of fascia and subcutaneous tissues , sometimes involving muscle and skin .
treatment is with haemodynamic support of sepsis , broad spectrum antibiotics , intravenous immunoglobulin and extensive debridement .
following debridement in this patient , sections from the specimen demonstrated an undifferentiated spindle cell sarcoma with areas of haemorrhage and necrosis , contrary to the initial presentation of presumed necrotizing fasciitis .
the treatment for breast sarcomas is planned by a multidisciplinary team and follows the treatment model of sarcomas in other locations .
localized tumours should be treated by complete excision , while mastectomy should be performed for more sizeable tumours .
adequate surgical excision seems to be one of the most important prognostic factors along with the tumour 's diameter and grade .
axillary dissection is unnecessary for breast sarcomas , as they rarely metastasize via the lymphatic system .
while chemotherapy is the mainstay of treatment for advanced systemic disease , radiotherapy has a role in lymphatic metastasis and preventing loco - regional recurrence .
the reported 5-year survival in patients with breast sarcomas varies between 40 and 91% in different studies .
 breast sarcomas are rare neoplasms arising from the few epithelial elements of the gland . 
 it represents much < 1% of all breast cancer . of the heterogeneous group of sarcomas , 
 the more common subtypes include spindle cell sarcoma . 
 the main risk factor for the development of breast sarcomas is previous radiation therapy following breast - conservation surgery for breast cancer or non - hodgkin 's lymphoma . 
 we report on an idiopathic presentation of spindle cell sarcoma in an otherwise healthy middle - aged woman . 
 an emphasis is made on the rare occurrence of lymphatic metastasis . 
 we discuss our recommended management strategy with particular reference to the benefit of multidisciplinary team decision - making . 
INTRODUCTION
CASE REPORT
DISCUSSION