The purpose of this study was to investigate possible differences in the primary in situ cellular immune response between patients with and without relapse of Stage IB cervical squamous cell carcinoma.Paraffin-embedded tissue from 40 patients (20 with and 20 without relapse) was evaluated. Sections were immunostained for CD1a + , CD3 + , CD4 + , CD8 + , CD20 + , CD45RA + , CD45RO + , CD57 + , CD68 + and GrB + cells. Immune cell profile densities were estimated using stereology.We found significantly lower densities of CD3 + , CD4 + , CD8 + and CD57 + cells (both intra- and peritumoral) in tissue from patients who had relapse. Also densities of intratumoral CD1a + cells and peritumoral CD20 + , CD45RA + and CD45RO + cells were significantly lower among patients with relapse.This study demonstrates striking differences in the cellular immune response between patients with and without relapse within 5 years. The results are of potential value in adjuvant immunotherapy and prediction of prognosis.