Impact of prior extrapulmonary cancer on survival after lung cancer: a systematic review and meta-analysis

OBJECTIVE: This review aimed to examine the impact of previous extrapulmonary malignancies on the overall survival (OS) of lung cancer patients.MATERIALS AND METHODS: The online databases of PubMed, Embase, Scopus, and Web of Science were explored for studies published up to 22nd December 2022 and comparing out-comes of first lung cancer vs. second primary lung cancer with a history of previous extrapulmonary malignancy. Studies were to report ad-justed data on OS. Meta-analysis was performed in a random-effects model.RESULTS: Nine retrospective studies were eligible. A total of 267,892 lung cancer patients with prior extrapulmonary malignancy and 1,351,245 primary lung cancer patients were analyzed in the studies. Meta-analysis of all studies showed that prior extrapulmonary malignancy results in poor OS in lung cancer patients as compared to those with no history of such cancer (HR: 1.27 95% CI: 1.07, 1.50 I2=83%). The results did not change on sensitivity analysis. No publication bias was noted.CONCLUSIONS: The result of this meta -analysis indicates that a history of prior extrapulmonary malignancy results in poor OS in patients with lung cancer. Caution is needed in the interpreta-tion of the results owing to high interstudy hetero-geneity. Further research is needed to assess how factors like the type of extrapulmonary malignan-cy, time interval of diagnosis, cancer stage, and treatment modality impact this relationship.