ALK Gene Rearrangemnet in Lung Adenocarcinoma

Abstract

Objective: To assess the frequency of ALK gene rearrangement among patients presenting with lung adenocarcinoma at tertiary care hospital of Karachi, Pakistan.

Study Design: Prospective longitudinal study

Place and Duration of Study: Department of Medical Oncology, Jinnah Postgraduate Medical College Karachi, Pakistan from May 2019 Mar 2020.

Methodology: Total 185 patients with confirmed diagnosis of stage IV lung adenocarcinoma who were unresectable and metastatic of age 20-75 years of either gender were included in the study using non-probability consecutive sampling technique. Patients were subjected for ALK mutation analysis using fluorescent in situ hybridization technique.

Results: Out of 185 patients, the ALK rearrangements were found positive in 27 tumors whereas it was negative in 158 tumors. Among ALK positive cases, majority of the patients were of aged less than 50 years (n=18, 66.7%).The statistically significant difference was found between age and ALK gene rearrangement (p<0.05). Whereas no statistically significant relationship was found between ALK rearrangements and gender, ethnicity and smoking status (p>0.05).

Conclusion: The results showed positive rearrangement of ALK gene in 15% of the patients which is in contrast to 7% patients found in western studies. ALK gene testing has become standard of care in patients of adenocarcinoma who are EGFR negative so that treatment like ALK gene inhibitors such as alectinib, brigatinib, ceritinib, crizotinib, and lorlatinib can be tailored accordingly.