123P - Incidence and outcomes of anaplastic lymphoma kinase (ALK) and ROS 1 positive advanced NSCLC: A real world experience

Background

A novel fusion gene of EML4-ALK and ROS 1 has been identified in a subset of non-small-cell lung cancers (NSCLCs). Patients with the ALK-EML4 and ROS1 fusion gene demonstrate unique clinicopathological characteristics and treatment with targeted therapy led to improved survivals.

Methods

Data of advanced NSCLC patients diagnosed between 2016 and 2022 with ALK and ROS1 positivity were analyzed. Detection of ALK was done by IHC or fluorescent in situ hybridization (FISH) and ROS1 was done by FISH.

Results

A total of 776 advanced NSCLC patients between 2016 and 2022 were tested for ALK of which 63(8.1%) were positive. The median age at presentation was 50 years (range,19-80 years). Of 63 patients, 34(54%) were males and 29(46%) were females. Cough (83%) was the most common symptom at presentation followed by dyspnea (73%), anorexia (59%) weight loss (59%) and chest pain (43%). The median duration of symptoms was 3 months. 44(86%) patients were never smokers and 9(14%) patients had history of smoking or tobacco usage. The most common site of metastases was opposite lung(59%), bone(50%) followed by pleural effusion(41%). Brain metastasis were seen in 13(21%) patients. Detection of ALK positivity was done by IHC and FISH in 45(72%) and 18(28%) patients respectively. Of 63 patients, 52 patients received atleast 4 months of treatment and were assessed for survival. First-line therapy was crizotinib, chemotherapy followed by maintenance crizotinib, ceritinib, alectinib in 40(77%), 4(7.7%), 6(11.5%) and 2(3.8%) patients. The median PFS was 16 months (range, 4-52). At a median follow up of 14 months, the 1-year progression free and overall survival was 71% and 75%. The 2 year and 3 year OS were 54% and 30% . Out of 322 patients tested for ROS1, 9(2.8%) were positive for ROS1 translocation and received first-line therapy with Crizotinib. The one year PFS and OS were 75% and 89%.

Conclusions

ALK and ROS1 positivity was seen in 8.1% and 2.8% of advanced NSCLC patients. Majority of patients were never smokers. Opposite lung and bone were the most common site of metastases. 3/4^th of the patients had one-year survival rate and the survival rates in the real world are better than reported in the randomized studies. Crizotinib is well tolerated in majority of patients.

Editorial acknowledgement

Clinical trial identification

Legal entity responsible for the study

Nizam's Institute of Medical Sciences.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.