Surgical outcomes of second primary lung cancer after the extrapulmonary malignancy

Abstract

Objective: To study the surgical outcomes of patients with a second primary lung cancer after the extrapulmonary malignancy.

Materials and methods: Patients who underwent surgical resection for lung cancers between January 2005 and December 2014 were reviewed. Clinical data, imaging characteristics of tumors, surgical approaches, and outcomes were analyzed with a mean follow-up of 97 months.

Results: Of 1075 patients, 166 (15.4%) had a second primary lung cancer after extrapulmonary malignancy. There were no differences in overall 5-year survival rates (81.8% for the group of lung cancer vs. 72.9% for the second primary lung cancer group, p = 0.069) and 5-year disease-free survival (70.1% for the lung cancer group vs. 70.3% for the second primary lung cancer group, p = 0.863) between the two groups. Gender, performance status, tumor size, and maximum standard uptake value (SUVmax) were significantly different between the two groups. After propensity-score matching analysis, patients in the group with lung cancers had better 5-year overall survival (88.1% vs. 72.1% for the group with second primary lung cancers, p = 0.016) and 5-year disease-free survival (80.6% vs. 70.3% for the group with second primary lung cancers; p = 0.054). In the second primary lung cancer group, the patients with preceding breast or thyroid cancers had better prognoses than did those with other extrapulmonary malignancy.

Conclusions: Second primary lung cancers following extrapulmonary malignancies were not uncommon. Surgical resection is considered for early stage secondary primary lung cancer after meticulous work up and result in fair outcome.

Keywords: Prognosis; Second lung cancer; Surgery.

Fig. 1

a Overall survival (OS) curves for the first and second lung cancer groups. The 5-year OS was 81.8% for the lung cancer group, and 72.9% for the second lung cancer group (log-rank test; p = 0.069). b The 5-year disease-free survival (DFS) rates were 70.1% for the lung cancer group vs. 70.3% for the second lung cancer group (log-rank test; p = 0.863)

Fig. 2

a OS curves after stratifying for surgical procedure. Anatomic resection produced a 5-year OS of 82.0% for the lung cancer group, and 71.8% for the second lung cancer group (log-rank test; p = 0.063). b For those undergoing sublobar resection, there was 5-year OS of 82.5% for the lung cancer group, and 73.2% for the second lung cancer group (log-rank test; p = 0.795)

Fig. 3

a Disease-free survival (DFS) curves after stratifying for surgical procedure. Anatomic resection gave a 5-year DFS of 66.6% for the lung cancer group, and 63.9% for the second lung cancer group (log-rank test; p = 0.957). b Sublobar resection produced a 5-year DFS of 83.4% for the lung cancer group and 94.2% for the second lung cancer group (log-rank p = 0.222)

Fig. 4

Results are shown after PSM analysis of age, tumor size, and stage. a The 5-year OS was 88.1% for the lung cancer group, and 72.9% for second lung cancer group (log-rank test; p = 0.016). b The 5-year DFS was 80.6% for the lung cancer group and 70.3% for the second lung cancer group (log-rank test; p = 0.054)

Fig. 5

Cancer-specific survival curves for patients who developed a second lung cancer. a The 5-year OS for patients with breast cancer was 76.7%; 43.1% for those with a GI tract cancer, 86.9% for those with GU tract cancer; 100% for those with thyroid cancer; 46.7% for those with HCC, and 77.8% for those with other types of cancers (log-rank test; p = 0.008). b The 5- year DFS for patients with breast cancer was 73.1%; 58.9% for those with GI tract cancer, 76.9% for those with GU tract cancer; 87.5% for those with thyroid cancer; 54.7% for those with HCC; and 64.4% for those with other types of cancers (log-rank test; p = 0.498)