The prognoses of patients with
non-small-cell lung cancer (NSCLC) harboring
anaplastic lymphoma kinase (ALK) gene rearrangement have dramatically improved with the use of ALK
tyrosine kinase inhibitors. Although immunological and nutritional markers have been investigated to predict outcomes in patients with several
cancers, their usefulness in targeted
therapies is scarce, and their significance has never been reported in patients receiving first-line treatment with
alectinib. Meanwhile, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (PLR) has been investigated during
crizotinib treatment. This multicenter retrospective study evaluated 42 consecutive Japanese patients with ALK-positive NSCLC who received first-line treatment with
alectinib. Immunological and nutritional markers were evaluated at baseline and 3 weeks after
alectinib introduction, and their significance in predicting progression-free survival (PFS) was explored. PFS duration was significantly associated with baseline PLR (hazard ratio (HR): 2.49, p = 0.0473), systemic immune-
inflammation index (SII; HR: 2.65, p = 0.0337), prognostic nutrition index (PNI; HR: 4.15, p = 0.00185), and the 3-week values for SII (HR: 2.85, p = 0.0473) and PNI (HR: 3.04, p = 0.0125). Immunological and nutritional markers could be useful in predicting the outcomes of first-line treatment with
alectinib. Since PLR and SII consist of platelet counts, platelet count could be an important constituent of these markers.