Prognostic Impact of Histologic Subtype in Non-Small Cell Lung Cancer Patients Treated with Gamma Knife Radiosurgery: Retrospective Analysis of 104 Patients
AIM: In this study, factors affecting survival, local failure, distant brain failure, whole brain failure and whole-brain radiation therapy
(WBRT) free survival according to histological subtypes were investigated in patients with brain metastases from non-small cell lung
MATERIAL and METHODS: Patients with positive pathology reports for adenocarcinoma (ACA) and squamous cell carcinoma
(SCC) were included in the study. Seventy-eight ACA and 26 SCC patients were included in the study. Patients with previous history
of cerebral metastasis surgery and WBRT were excluded from the study.
RESULTS: The median survival was calculated as 12.6 months for patients with ACA and 5.9 months for patients with SCC.
One-year distant brain failure was calculated as 65.1% in ACA patients and 39.6% in SCC patients. One-year whole brain failure
was calculated as 58.1% in ACA patients and 39.6% in SCC patients. The one-year freedom from WBRT rate was calculated as
72.8% in ACA patients and 56.3% in SCC patients. SCC histology was considered as a significant factor in deterioration of overall
survival in multivariate analysis. SCC histology, the increase in the number of metastases and RPA class were factors that caused
an increase in distant brain failure. Also, SCC histology, the increase in the number of metastases and RPA class were factors that
caused an increase in whole brain failure.
CONCLUSION: SCC histology may be an important prognostic factor for overall survival. Also, due to high distant brain failure rate
in SCC histology, WBRT can be added to treatment early.