Does Pleural Invasion Lead to Worse Outcomes in Early NSCLC?

TOPLINE:

In patients with small, peripheral non–small cell lung cancer (NSCLC), visceral pleural invasion leads to worse disease-free and recurrence-free survival as well as higher rates of recurrence, regardless of the extent of surgical resection, new data show. However, the presence of visceral pleural invasion does not appear to significantly affect overall survival.

METHODOLOGY:

• Previous research has shown that lobar and sublobar resections are associated with similar outcomes in patients with peripheral NSCLC who have small tumors (≤ 2 cm). However, the impact of visceral pleural invasion on recurrence risk and survival outcomes in this population remains unclear.
• Researchers conducted a secondary analysis of the CALGB 14src5src3 clinical trial, which included 697 patients with clinical stage T1aNsrc NSCLC (median age, 67.8 years) who were randomly assigned to undergo either lobar or sublobar resection.
• In this post hoc analysis, patients were stratified and compared based on the absence (n=566) or presence (n=113) of visceral pleural invasion. (Clinical tumor size was ≤ 2 cm for all patients, though pathologically determined tumor size exceeded 2 cm for 83 patients overall.)
• The primary outcome was disease-free survival. Secondary outcomes were overall survival, recurrence-free survival, and the rates of locoregional and systemic recurrence. The median follow-up was 7 years.

TAKEAWAY:

• Patients with visceral pleural invasion had significantly worse disease-free survival at 5 years (53.3%) than those without invasion (65.9%).
• Patients with visceral pleural invasion had worse disease-free survival, regardless of the extent of parenchymal resection. The 5-year disease-free survival was 66.3% after lobectomy and 65.6% after sublobar resection in patients without visceral pleural invasion (hazard ratio [HR], 1.src1; P=.96) and 53.1% vs 53.5%, respectively, in those with visceral pleural invasion (HR, 1.src3; P=.92). This finding held when restricting the analysis to patients with pathologically determined tumors (size ≤ 2 cm).
• Patients with visceral pleural invasion experienced higher rates of disease progression (41.6% vs 27.6% in those without invasion; P=.srcsrc2) and distant recurrence rates (23.9% vs 14.6%, respectively; P=.src1). Locoregional recurrence rates were also higher (15.src% vs 1src.8%, respectively) but not significantly so (P=.19). Notably, more than 5src% of recurrences were systemic.
• The presence of visceral pleural invasion was associated with worse recurrence-free survival at 5 years (73.1% vs 58.2%; P=.src1). However, the 5-year overall survival rates were similar between those with and without invasion (74.7% vs 8src.5%; P=.31).

IN PRACTICE:

The presence of visceral pleural invasion was associated with high recurrence rates, which were “not mitigated by larger parenchymal resections, suggesting the presence of micrometastatic disease at diagnosis despite the small tumor size and absence of nodal metastases,” the authors noted.

SOURCE:

The study, with Nasser Altorki, MD, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York City, was published online in JAMA Oncology.

LIMITATIONS:

The unplanned exploratory design limited the generalizability of the study findings. The trial was underpowered to detect the differences in survival based on pathologic staging. The lack of central pathologic review limited definitive conclusions.

DISCLOSURES:

The study was supported by the National Cancer Institute of the National Institutes of Health and partly by Covidien/Tyco/Ethicon. Several authors reported receiving grants and personal fees and having other ties with various sources.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.