Long-term outcome from a study on the prevention of postoperative recurrence in patients with renal cell carcinoma: could PBL be a predictor of postoperative recurrence in patients postoperatively treated with IFN-gamma?

Abstract

This study examined the outcome of postoperative recurrence therapy on renal cell carcinoma (RCC) prevention involving treatment with single doses of interferon-gamma (IFN-gamma). From 1990-2000, 37 patients with no distant metastasis at the time they underwent a nephrectomy were enrolled in this investigation. Subcutaneous IFN-gamma was administered once a week. Total and differential white blood cells were counted before the pre-administration of IFN-gamma and then monthly thereafter for all patients. Blood lymphocyte subsets were analyzed phenotypically by direct immunofluorescence. Disease-free survival rates (DFSR) at 5 and 10 years were 81.7% and 75.9%, respectively. To clarify the effects of preoperative peripheral blood lymphocyte (PBL) and NK activity on DFSR, we categorized the patients into two groups according to the median number of PBL before the administration of IFN-gamma. Except for CD11b, PBL level had no effect on DFSR. Multiple logistic regression analysis showed that CD11b levels greater than 16.5% were associated with 25.35 odds ratio increase in the risk of postoperative recurrence. A multivariate analysis found that CD11b may be an independent factor for postoperative recurrence. In terms of preventing postoperative recurrence, our results showed that an elevated CD11b level may indicate patients who can benefit from further combination therapy.

[目的]腎細胞癌術後再発に対するインターフェロンγの単剤投与の有用性について検討した.[対象と方法]1990～2000年までの間に原発巣摘除時に転移病巣のない腎細胞癌37例を対象とした.インターフェロンγを毎週連続で皮下投与して末梢血のリンパ球の分画について, 投与前, 投与後各1ヵ月ごとにflow cytometryを用いて検討した.[結果]37例中7例に再発が認められ, 非再発率は5年が81.7%, 10年が75.9%であった.術後再発に関わる影響を調べるため末梢血リンパ球とNK活性について投与前の中央値でおのおの2群に分けた.CD11bとNK活性を除いて術後再発に関連は認められなかった.多変量解析の結果, 投与前CD11bが16.5%以上だと16.5%未満の症例に比較して25.35倍術後再発が高く, 逆に投与前NK活性が13%以上の症例は0.25倍術後再発が減少する.[結語]多変量解析の結果術後に補助療法としてインターフェロンγ投与した症例では, CD11bとNK活性が術後再発に関わる独立した因子であることが判明した.また腎細胞癌の術後再発予防という観点からCD11bが高く, NK活性が低い症例には, さらなるcombination therapyが必要と考えられる(著者抄録)