Essay Example on Leiomyosarcomas are a group of rare heterogeneous malignant Tumours

Leiomyosarcomas are a group of rare heterogeneous malignant tumours arising from smooth muscle mesenchyme The tumour may arise at any site however the uterus gastrointestinal tract and soft tissues are the most frequently affected Within the lung the disease most commonly occurs as a consequence of distant metastasis however may originate within the lung as a discrete disease entity which is exceptionally rare We present the case of a 66 year old gentleman who presented with dyspnoea and was found to have an incidental pulmonary nodule in which a biopsy subsequently confirmed an extremely rare primary pulmonary leiomyosarcoma Leiomyosarcomas are a group of heterogeneous tumours which arise from the mesenchyme of smooth muscle 

The most common sites of origin include the uterus gastrointestinal tract and soft tissues In the lung the disease most frequently arises as a consequence of distant metastasis from a primary lesion elsewhere however it may arise as a distinct disease entity within the lung which is extremely rare Primary pulmonary leiomyosarcoma was first described by Davidsohn et al in 1903 and accounts for less than 0 5 of all primary lung malignancies 1 2 Whilst patients may present with similar symptoms to other more commonly encountered bronchogenic tumours many patients remain asymptomatic and are identified incidentally Although radiological investigation plays a pivotal role in establishing the diagnosis the findings are often nonspecific with pulmonary leiomyosarcomas presenting a solitary well defined nodules as was the case with our patient 3 As such a definitive diagnosis can only be established by careful pathological examination of a tumour specimen combined with immunohistochemical staining to ascertain a likely site of origin Due to the high prevalence of pulmonary nodules often detected incidentally following routine chest radiography or computerised tomography this case therefore highlights the importance of considering a primary pulmonary leiomyosarcoma in any patient presenting with a pulmonary nodule particularly in those patients who enter a nodule surveillance pathway as early detection and resection has demonstrated more favourable outcomes and improved rate of survival Leiomyosarcomas are a group of heterogeneous malignant tumours which originate in the smooth muscle mesenchyme and most often arise within the uterus soft tissues and gastrointestinal tract Primary pulmonary leiomyosarcoma PPL of the lung is extremely rare and accounts for less than 0 5 of all malignant lung neoplasms 1 Within the lung PPL may originate from the smooth muscle cells of the parenchyma bronchial walls or pulmonary arteries and is classified according to the site of origin 4 The intrapulmonary type is the most common type 5 

Pulmonary leiomyosarcomas demonstrate a wide spectrum of differentiation and histologically are grossly characterised with a firm grey or white surface 4 Microscopically malignant spindle cells are observed with slender cigar shaped nuclei arranged in interweaving fascicles 8 Low grade tumours are characterised by low mitotic rates and absence of cellular atypia necrosis and haemorrhage whereas high grade tumours have marked cellular atypia high mitotic rates with significant haemorrhage and necrosis present 7 Immunohistochemistry plays an essential role in differentiating PPL from primary bronchogenic tumours alongside identifying the source of smooth muscle and usually stain positive for actin smooth muscle actin desmin vimentin and negative for carcinoembryonic antigens cytokeratin neuroendocrine filaments S100 proteins and leukocyte common antigens 4 6 Due to the rarity of the disease the treatment of PPL has not yet been standardised Current treatment modalities include surgical resection chemotherapy and radiotherapy For small solitary well differentiated tumours if amenable complete surgical resection is considered curative For larger tumours preoperative radiotherapy may be indicated to decrease tumour size prior to attempting surgical resection 6 In those not amenable to surgical resection then palliative chemotherapy and radiotherapy remains the modality of choice Despite this the prognosis remains poor with 5 year survival approaching only 35 9