CD98 expression is associated with poor prognosis in resected non-small-cell lung cancer with lymph node metastases

The purpose of this study was to evaluate the prognostic value of L-type amino acid transporter 1 (LAT1) and 4F2 heavy chain (CD98) expression in resectable non-small-cell lung cancer (NSCLC) patients with N1 and N2 nodal involvement.

A total of 220 consecutive patients were retrospectively reviewed. Immunohistochemical expression of LAT1, CD98, Ki-67 labeling index, vascular endothelial growth factor (VEGF), and microvessel density (MVD) was correlated with clinical features and prognosis of patients after complete resection of the tumor.

Positive expression of LAT1 and CD98 was recognized in 60% (132/220) and 47% (103/220), respectively (P = 0.021). A positive rate of LAT1 expression was significantly higher in squamous cell carcinoma (SQC) (91%; 65/71) and large cell carcinoma (LCC) (82%; 9/11) than in adenocarcinoma (AC) (42%; 58/138). Moreover, a positive rate of CD98 expression was also significantly higher in SQC (76%; 54/71) and LCC (73%; 8/11) than in AC (30%; 42/138). LAT1 expression was significantly correlated with CD98, Ki-67 labeling index, VEGF, and MVD. The 5-year survival rates of LAT1-positive and LAT1-negative patients and CD98-positive and CD98-negative patients, were 43% and 48% (P = 0.1043), respectively and 39% and 50% (P = 0.0239), respectively. Multivariate analysis confirmed that positive expression of CD98 was an independent factor for predicting a poor prognosis.

In our limited series, CD98 is a pathological factor that predicts prognosis in resectable adenocarcinoma patients with N2 disease.