Adenosquamous Carcinoma Lung-CT

50 year male with cough and CT showed a large well defined regular, heterogeneously enhancing , peripheral , broadbased , noncalcifying, nonnecrotised SOL with no defintie bronchus cutoff. The medial and proximal lung of upper lobe displays airbronchogram. Mediastinal lymphadenopathy of moderate size is suggested in paratracheal and precarinal region with possible involvement of ipsilateral hilum. Ribcage, pleuralmargin, soft tissues, rest of the lung fields and adrenal glands are normal along with supraclavicular regions. CT value suggests solid lesion consistent with mass lesion

CT guide FNAC suggested adenosquamous carcinoma

AdenoSquamous carcinoma is unusual and rare pulmonary malignancy with two distinct cell types. Constitutes only 0.4 to 4% of all pulmonary malignancies.

Etiology: can arise from damaged parenchyma posibly from pneumoconiosis, and radiaiton fibrosis

Histology was defined by WHO in 1982 , modified by japanese lung society recently with suggestion of atleast 10% of microscopic appearance from both adeno and squmous components This can arise by collison of two adjacent tumours and yet distinct tumours , or as some consider as high grade mucoepidermoid ca with high squamous content or adenoca with squamous metaplasia

Studies-Mass Gen Hosp reports them to be peripheral in 83%, right lung involv in 63%,size varying from 7 to 65 mm with presence of cavitation in only 14%. It has been recently reported in chest journal presenting as multiple cavitating nodules mimicking infections . Prognosis is generaly considered poor with nagasaka et al reporting 6.2%survival at 5 yrs compared to appx 42% each for adeno and squamous varieties amongst review involving 1400 cases.

Case Submitted by – Dr Sudheer , Dr Krishnamohan and Dr MGK Murthy