Background: The acquisition of immune reaction in the peripheral blood is expected to play a critical role in the prevention of tumor progression. However, the clinical role of the circulating immune response against human cancer remains unclear.
Methods: Serum samples from 68 consecutive patients who underwent resection for pulmonary adenocarcinoma were obtained before the operation. The serum levels of interferon gamma and interleukin 4 were measured and the impact on the clinical features was assessed. According to the predominance of the cytokine levels, the patients were classified into 4 groups: interferon gamma only (T(H)1), interleukin 4 only (T(H)2), both (T(H)0), and neither (T(H)X).
Results: In the T(H)1 group, 18 of 22 patients (81.8%) were free from lymph node metastasis, whereas 5 of 7 patients (71.4%) in the T(H)2 group had lymph node involvements. As a result, 62 patients underwent complete resection, with 9 of 19 patients (47.3%) in the T(H)1 group having recurrence, but no relapse of the disease appearing in the T(H)2 group during the observation period. The disease-free interval for the T(H)2 group was significantly longer than that for the T(H)1 group (44.2 mo vs 26.1 mo, P =.03).
Conclusions: Assessing the serum T(H) profile on the basis of the predominance of the serum interferon gamma or interleukin 4 is important to presume the ongoing responses of T cells against the tumor burden.