前立腺癌における腫瘍マーカー(前立腺性酸性ホスファターゼ,γ-セミノプロテイン,前立腺特異抗原)の検討

Abstract

1979年から1987年までに, 治療前にPAP, γ-Sm, PAのいずれかを測定した前立腺癌200例および前立腺肥大症179例を対象として, PAP, γ-Sm, PAの有用性を比較検討した.1)前立腺癌の検出率は, PA, γ-Sm, PAPの順に高かった.2)前立腺肥大症の特異性はPAP, γ-Sm, PAの順に高いため, 前立腺癌の診断効率はPAPが最も優れ, ついでγ-Sm, PAが最も低値であった.3) PAPとγ-Smとを併用することによる検出率の上昇は若干名のみあり, またPAP, γ-Sm, PAを併用することによる検出率の上昇は認められず, cut off値を10 ng/mlと高く設定しても少数例のみ認められた.併用することにより, 特異性が低下するために, 診断効率はPAP単独よりも低値となったので, 診断面での併用測定の有用性は大きなものではなかった.4)未治療前立腺癌において, PAPとγ-Smとの間には相関がなく, γ-SmとPAとの間は低かったが, PAPとPAとの間は高い相関を示した.5)再燃例の検討において, PAPは再燃時約9割が異常値を示した.PAP正常例の大多数はγ-Sm, PA共異常値を示したので, 複数マーカー測定の意義を認めた

The levels of prostatic acid phosphatase (PAP), gamma-seminoprotein (gamma-Sm) and prostate specific antigen (PA) were determined in the serum of 200 untreated patients 28 patients with reactivated prostatic cancer and 179 patients with benign prostatic hypertrophy (BPH) from 1979 to 1987. PAP and gamma-Sm were determined using an Eiken and Chugai kit, respectively and PA was assayed using an Eiken or Travenol kit. The sensitivity of PAP, gamma-Sm and PA respectively in the untreated prostatic cancer cases was 0, 0% and 67%, for Stage A1, 25, 17 and 100% for Stage A2, 23, 50 and 60% for Stage B, 62, 81 and 94% in Stage C, 58, 67 and 90% for Stage D1, 86, 88 and 100% for Stage D2. The specificity of PAP, gamma-Sm and PA is 89, 69 and 43%, respectively. The efficiency of PAP was the highest at all stages as a whole, but when compared at each stage, gamma-Sm was the highest at Stages B and C. The sensitivity of simultaneous assays of PAP and gamma-Sm was slightly increased, but sensitivity was not increased by simultaneous use of three markers. The efficiency of a simultaneous assay was lower than that of a single assay with PAP. However, combined determination of gamma-Sm or PA with PAP was found to be useful for monitoring the clinical course of the reactivated patients. Correlation between PAP and PA levels was high, but that between gamma-Sm and PA levels was low. There was no correlation between PAP and gamma-Sm levels. In conclusion, PAP is the most valuable marker for prostatic cancer, and gamma-Sm is of value for use in combination with PAP. However, an additional PA assay was not found to be of advantage.