subcuteneous swelling as metastases are an uncommon presenting feature for primary solid tumors like lung cancer usually in the range of 1.52.6% .
it is important to distinguish such metastases from a soft - tissue mass as they may represent the first clinical sign of an occult tumor . in this report
, we describe an unusual case of small - cell lung cancer metastasizing to his anterior chest , back and left arm as soft tissue nodule at the time of initial diagnosis ; an aggressive cancer which has a poor prognosis owing to its late presentation .
a 64-year - old male , chronic smoker presented in the medicine outpatient department with complaints of breathlessness , loss of weight , multiple swellings on the chest , back and left arm since 2 months .
there was no history of trauma , pulmonary tuberculosis , chronic obstructive pulmonary disease , bronchial asthma , ischemic heart disease , hypertension or diabetes . on examination , there were firm , variegated and no tender cystic swellings on the anterior chest , back and left arm ( figure 1 ) .
the hemoglobin was 9.6 g% , total leukocyte count was 6300/cmm with a differential of 45% neutrophils , 37% lymphocytes , 17% monocytes and 1% eosinophils , in the peripheral smear .
serum calcium , phosphorus and alkaline phosphatase were 13.2 mg% , 4.0 mg% and 7.2 bodansky unit , respectively .
fine needle aspiration cytology of the swelling from chest showed small cell lung carcinoma seen as small round cells in rosettes and nests with high n / c and pepper salt chromatin ( 40 , pap .
computerized tomography of the chest showed pleural effusion , rib fracture with multiple small hypoechoic shadow suggestive of lung cancer ( figure 3 ) .
he was referred to radio - oncology department for further management but he refused due to non - affordability .
figure 2small cell lung carcinoma seen as small round cells in rosettes and nests with high n / c and pepper salt chromatin ( 40 , pap .
stain ) . small cell lung carcinoma seen as small round cells in rosettes and nests with high n / c and pepper salt chromatin ( 40 , pap .
figure 3computerized tomography of the chest showing pleural effusion and rib fracture with multiple small hypoechoic shadow , suggestive of lung cancer .
computerized tomography of the chest showing pleural effusion and rib fracture with multiple small hypoechoic shadow , suggestive of lung cancer .
small cell lung cancer results from bronchial epithelial cells , which are relatives of kultchitsky cells , a type of intestinal epithelial cell .
it is much lower compared to adenocarcinomas ( 2.95% ) and squamous cell carcinomas ( 1.16% ) of the lung .
the disease most frequently metastasizes to the central nervous system , bone marrow and suprarenal glands .
small cell lung cancer may be accompanied by paraneoplastic syndromes , superior vena cava syndromes , compressions to the spinal cord and , very rarely , skin metastases . although they can occur in any part of the skin , most common sites for cutaneous metastases are chest , back , abdomen , and scalp .
diagnosis may be delayed by several months , unless the skin lesion grows rapidly or other sites such as the lung or liver are affected by the tumor 's spread .
early recognition of tumor from a suspicious skin lesion may lead to initiation of treatment before widespread metastases occur . in our case ,
the metastasis in the form of subcutaneous swelling was found simultaneously with the primary lung tumor , facilitating diagnosis .
although at the time of initial presentation he also had pleural effusion and rib fracture . moreover in this case nature of swelling was not suspicious rather it looked like lipoma and on aspiration cytology it was metastasis from small cell lung cancer .
the basic metastatic course can occur in the following steps : detachment from the primary tumor followed by invasion , intravasation into a vessel , circulation , stasis within a vessel , extravasation , invasion into recipient tissue bed , and proliferation . in conclusion , as seen in this case of rare unexpected skin metastasis of small cell lung carcinoma , which lack a pathognomonic physical appearance , like rapid enlargement , ulceration , tender , physicians should be vigilant about this entity .
any skin lesions in the form of swelling should be evaluated meticulously and biopsies should be done to exclude metastases in the clinical scenario of breathlessness , chest pain and loss of weight especially in old age . because in this case though both primary and metastasis were detected at the same time , earlier diagnostic anticipation about this cuteneous swelling could have different and better prognosis .
 subcutaneous swelling as first clinical presentation of small cell lung carcinoma is uncommon and rarely reported in literature . 
 this case highlights a rare presentation in which subcutaneous swelling was the first clinical manifestation of a small cell carcinoma of lung which also had metastasis to rib bone , muscle and pleural involvement as pleural effusion . 
 we describe the case of a 64-year - old male patient who presented with dyspnea , pleuritic pain , loss of weight and nodule on his anterior chest , back and left arm suspicious of lipoma . 
 biopsies revealed small cell carcinoma of lung . 
 this case demonstrates the meticulous work up of subcutaneous swelling in the clinical scenario of breathlessness , chest pain and loss of weight . 
Introduction
Case Report
Discussion