Decreased Absolute Counts of T Lymphocyte Subsets and Their Relation to Disease in Squamous Cell Carcinoma of the Head and Neck

Abstract

Results: Patients with SCCHN had significantly lower absolute numbers of CD3؉ CD4؉, and CD8؉ T cells than normal controls. However, no differences in the percentages of T-cell subsets between patients and normal controls were observed. Patients with active disease had significantly lower CD3؉ and CD4؉ T-cell counts than those with NED. Patients who had NED after surgery and radiotherapy had the lowest T-cell counts among the NED cohort. Patients who had NED for >2 years did not recover their T-cell counts, and the T-cell imbalance was evident many years after curative surgery. The tumor-node-metastasis (TNM) stage or site of the disease was not related to the absolute T-cell count. Patients with recurrent disease at the time of blood draw tended to have the lowest CD4؉ T-cell counts. Conclusions:Patients with SCCHN have altered lymphocyte homeostasis, which persists for months or years after curative therapies.

Characteristics of CD4+CD25+ regulatory T cells in the peripheral circulation of patients with head and neck cancer

“…We have previously reported a decrease in absolute CD4 þ T-cell counts in patients with SCCHN relative to age-matched NC (Kuss et al, 2004a). In the cohort of patients studied here, the mean absolute CD4 þ T-cell count was 6107350 mm À3 , which is significantly lower than the normal mean count of 10057360 mm 3 (Kuss et al, 2004a).…”

“…The CD4 þ T-cell subset of lymphocytes was previously studied by us in patients with SCCHN Kuss et al, 2004a). We found that the absolute count of circulating CD4 þ T cells was significantly decreased in these patients (Kuss et al, 2004a).…”

“…In the cohort of patients studied here, the mean absolute CD4 þ T-cell count was 6107350 mm À3 , which is significantly lower than the normal mean count of 10057360 mm 3 (Kuss et al, 2004a). It was, therefore, important to determine whether the low absolute counts of circulating CD4 þ T cells could be explained by their apoptosis.…”

“…This observation supports our hypothesis that lymphocyte homeostasis disrupted by the presence of tumour fails to normalise following successful therapy. Immune abnormalities, including depressed absolute lymphocyte counts (Kuss et al, 2004a), elevated percentages of CD8 þ cells undergoing early apoptosis (Hoffmann et al, 2002), and signalling defects , persist for weeks or years after curative therapies in patients with NED. It appears that the enrichment in circulating T reg is also a persistent immune alteration that does not normalise following therapy.…”

“…We found that the absolute count of circulating CD4 þ T cells was significantly decreased in these patients (Kuss et al, 2004a). While the pool of naïve CD4 þ CD45RO-CD27 þ T cells was significantly smaller in patients than in age-matched normal controls (NC), the pool of memory CD4 þ CD45RO þ T cells was significantly expanded .…”