Investigation of systemic treatment effectiveness as A retrospective after the diagnosis of brain metastasis in non-metastatic small cell lung cancer

Purpose: The aim of this study was to investigate the demographic, histological and clinical characteristics of patients diagnosed with brain metastasis in metastatic non-small cell lung cancer, and to investigate the prognostic factors of treatment. In addition, it was aimed to analyze the effects of treatment on patient brain metastasis and systemic disease in patients who received chemotherapy or target therapy after brain metastasis. Method: In this study, files of 388 patients diagnosed with non-small cell lung cancer who were followed-up in Dicle University Faculty of Medicine Research and Practice Hospital Internal Diseases Medicine Oncology Department between January 1, 2010 and January 31, 2020 were scanned. Among these patients 167 patients were analyzed. Patient files and clinical characteristics were examined, prognostic factors of the case and treatment were investigated, and life analyzes were performed. The histopathological type, stage, driver mutation status, metastasis time, metastasis sites, radiotherapy status and the first treatment and control time after brain metastasis were examined. Overall survival was calculated from the detection of brain metastasis to the last control or patient death date. Results: 135 of the patients in our study (80.8%) males and 32 (19.2) were female. The median age of the patients was 63 years (29-90), and the most common histopathological type was adenocarcinoma (80.2%). 123 patients (73.7%) were metastatic at the time of diagnosis. Brain metastasis was present in 64 patients (38.3%) at the time of diagnosis. The median survival was 4.83 months in all patients. The ECOG score (OS: 5,38 months ECOG 0-1-2 group, 2,16 months ECOG 3-4, p=0,009), extracranial metastasis status (Overall survival extracranial metastasis present 3,5 months, non-present group 8,9 months, p<0,001), and the number of extracranial metastasis (Overall survival ≤2 number of extracranial metastasis group 6,9 months, >2 number of extracranial metastasis group 3,22 months, p=0,003) were found to be effective in the survival of the patients. Only lung metastasis presence were found to be significant in extracranial organ involvement (Overall survival: group without lung metastasis 6,76 months, group with lung metastasis 3,31 months, p<0,001). Survival was significantly longer for patients who received cranial radiotherapy for the second time (Overall survival: the group that received second time whole brain radiotherapy 17,6 months, the group didnt received second time brain radiotherapy 4,07 months, p=0,002) and for the group who received more than 2 line chemothreapy after brain metastasis (Overall survival: the group received less than 2 line chemotherapy 3,5 months, the group received more than 2 line chemotherapy 16,78 months, p<0,001). Treatment after brain metastasis was shown to have a significant effect on patient survival, and survival was found to be 8.67 months in the group receiving treatment and 2.95 months in the group not receiving treatment (p <0.001). Conclusion: Non-small cell lung cancer brain metastasis have a significant effect on patient survival, and it has been observed that systemic therapy in addition to surgery and radiotherapy significantly affects the patient's survival. Independent factors affecting survival are whether systemic therapy is administered or not [(HR: 0.553 (95% CI: 0.372-0.821), p = 0.003) and extracranial organ metastasis [(HR: 1.561 (95% CI: 1.009-2.416), p = 0.046 ] has been determined. Keywords: Non-small cell lung cancer, brain metastasis, prognosis