Increased Copy Number of Anaplastic Lymphoma Kinase Gene Signal in Lung Carcinomas: Is it Significant?

The anaplastic lymphoma kinase gene re-arrangement which is present in 3-5% cases of non small cell lung cancer is a somatic gene re-arrangement. The gold standard for the identification of this gene re-arrangement is fluorescence in situ hybridization. Many variant hybridization patterns have been documented. We present a case of polysomy of ALK gene in the absence of ALK gene re-arrangement in a 45 year old female who presented with brain metastasis. This is a rare case of polysomy of ALK gene reported in a non small cell lung carcinoma. It may be indicative of a worse prognosis and may predict high metastatic potential in these tumors.