3466 - Multiple primary cancers (MPC) in a series of lung cancer (LC) patient: incidence and outcome

Background

The number of cancer survivors has increased as a result of significant progress in prevention, diagnosis and treatment of malignant tumors and the incidence of MPC in surviving cancer patients (p) is also rising. This study investigates the co-occurrence of MPC among p diagnosed with lung cancer (LC).

Methods

Review of clinical data of all consecutive patients with histologically confirmed LC visited at our institution between October 2017 and January 2018.

Results

Out of 933 p, two primary cancers occurred in 115 cases (12%), including 25 p (3%) with three primary cancers. Patients with MPC were predominantly males (69%), smokers (85%) and 20% had known family history. Median age at the first tumor was 61 years (44-85). LC occurred as first neoplasm in 21% of the cases, as subsequent neoplasm in 64% and as two consecutive primary neoplasm in 15%. Most common cancer previous to LC diagnosis was colorectal in 23%, breast in 22%, prostate in 19%, head and neck in 12% and bladder in 11%. Treatment received for first cancer included surgery in 79%, chemotherapy in 50% and radiotherapy in 30%. Second tumor was prostate in 22%, bladder in 22%, colorectal in 19%, breast in 19% and head and neck in 8%. Surgery was performed in 66% of the cases with second cancer. Overall, median time from diagnosis of first to second neoplasm was 4 years (2.9 -5.2), without significant differences if primary tumor was LC or another neoplasm (p = 0.39). Of note, 25% had diagnosis of second primary cancer within 1 year. Smoking was significantly associated with shorter time to diagnosis of a second neoplasm (3.4 years vs 4.7 years for non-smokers, p = 0.03). With a median follow up of 2 years after diagnosis of second neoplasm, the 2-year survival rate was 93.7% (88.8-98.7%). Having a second cancer within 3 years significantly increased the risk of death (HR = 7.7, p = 0.02).

Conclusions

In our series, the frequency of the co-occurrence of MPC among LC p is 12%, indicating that surveillance strategies are recommended. Many p are treated with curative intent. Smoking increased risk of second primary, and diagnosis within 3 years of follow-up associates with poor outcome.

Clinical trial identification

Legal entity responsible for the study

Vall d'Hebron Institute Oncology.

Funding

Has not received any funding.

Editorial Acknowledgement

Disclosure

All authors have declared no conflicts of interest.