Survival Varies Little by Surgery Type in NSCLC With Micro Lesions

While low dose computed tomography has made it easier to detect small lung cancer lesions, that has not yet translated into significant new research to guide surgical decisions for patients with second primary non-small cell lung cancer (NSCLC) lesions with diameters of 2 cm or less.

In a new report in Surgery Today, investigators including corresponding author Shanqui Li, PhD, of the Peking Union Medical College in China, report on the outcomes of more than 500 cases in which patients had second primary NSCLC lesions of less than 2 cm in diameter. The authors compared the efficacy of 3 types of surgery—wedge resection, lobectomy, and segmentectomy—to see how survival and other outcomes varied based on treatment types.

Li and colleagues said a significant amount of research has looked at how best to treat patients with NSCLC in general. For instance, the data suggest that NSCLC cases with small lesions are best treated with lobectomy, but segmentectomy and wedge resection were indicated if lobectomy was not suitable in an individual case.

However, they said the evidence is inadequate to make recommendations for the subset of patients who have second primary NSCLC with small lesions.

“There is still limited evidence about whether lobectomy or sublobar resection is better, and the risk factors are unknown,” they said.

Li and colleagues therefore decided to query the Surveillance, Epidemiology, and End Results (SEER) database in search of patients with second primary NSCLC less than 2 cm in diameter. Cases were limited to those diagnosed between 2004 and 2015, and cases with T stages of T1.

A total of 568 patients were found. The investigators then used a series of analytical techniques to determine which types of surgery were most effective. The analysis showed a number of demographic factors were linked with patient prognosis, including age, sex, grade, and lymph node ratio. However, they found that the type of surgery a patient received did not significantly affect patient outcomes.

Li and colleagues then used the 4 prognostic factors to develop a nomogram model to visualize the prognosis for the patients.

Although the overall outcomes for patients suggested that survival did not vary significantly between surgical-type groups, Li and colleagues decided to undertake a propensity score matching process in order to minimize selection bias that might have been introduced due to uneven distribution of patients between the groups. That process confirmed that there were no significant survival differences between the surgical procedure groups. However, it did show that patients in the segmentectomy group had significantly higher cancer-specific survival rates compared with those in the lobectomy group.

“Thus, segmentectomy is recommended over lobectomy, but there is still not enough evidence to prove the effectiveness of other surgical procedures,” they wrote.

Li and colleagues said their study was limited by the inability to fully validate their findings against other databases, since other databases lacked the necessary information. They also noted that their study was retrospective in nature and conducted before the wide use of video-assisted thoracic surgeries, a factor that may impact survival rates.

Reference:

Wang Z, Wu Y, Huang J, Xie F, Gong L, Li S. Surgical strategies for patients with second primary non-small cell lung cancer lesions 2 cm or less in diameter. Surg Today. Published online May 6, 2022. doi:10.1007/s00595-022-02464-0