Sim S J, Glassman A B, Ro J Y, Lee J J, Logothetis C J, Liu F J
Division of Laboratory Medicine, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Ann Clin Lab Sci. 1996 Nov-Dec;26(6):487-95.
Small cell carcinoma (SCC) of the prostate is a rare and recently recognized subtype of prostate cancer. The neuroendocrine component of the prostate carcinoma is becoming more frequently detected in classic adenocarcinoma of the prostate. Clinically, these tumors represent a considerable portion of so called androgen independent prostatic carcinomas. It has been hypothesized that the neuroendocrine cells being admixed with adenocarcinoma is selected and emerges as a hormone refractory carcinoma after the androgen blockade. The SCC shows a spectrum from a mixed adenocarcinoma with SCC component to the extreme case of pure SCC. Characteristically, prostatic SCC shows low measurable serum level of traditional prostate tumor marker, prostatic specific antigen (PSA). Instead, SCC secretes several neural peptides and calcitonin (CT) is one of them. The usefulness of serum CT as a neuroendocrine marker was evaluated retrospectively in 16 patients with SCC of the prostate (5 pure SCCs and II combined adenocarcinoma and SCCs). The serum CT was measured by radioimmunoassay. In all the patients, serum CT level was measured after SCC was diagnosed histologically. All 16 patients presented with advanced tumor with extensive metastasis. Nine (56 percent) out of 16 cases showed elevated serum CT (range 42 approximately 2,654 pg/ml) and chemically supported the diagnosis of SCC. Owing to the retrospective nature of the study, the serum CT was measured only once in most of the cases, and the value of monitoring the disease progress or the responsiveness to the chemotherapy could not be evaluated. Survival analysis by logrank test did not show statistically significant prognostic value of serum CT in SCCs of the prostate. However, patients with extremely high serum CT level tend to have poor survival. Future studies are needed for further evaluation of serum CT as a disease monitor and prognostic marker in SCC of the prostate. Serum CT may have a role as a tumor marker in the early diagnosis of SCC of the prostate, which often is not diagnosed until the advanced stage.
前列腺小细胞癌（SCC）是一种罕见且最近才被认识的前列腺癌亚型。前列腺癌的神经内分泌成分在经典的前列腺腺癌中越来越频繁地被检测到。临床上，这些肿瘤占所谓雄激素非依赖性前列腺癌的相当一部分。据推测，与腺癌混合的神经内分泌细胞在雄激素阻断后被选择并演变成激素难治性癌。SCC表现出从具有SCC成分的混合腺癌到纯SCC的极端情况的一系列表现。典型的是，前列腺SCC显示传统前列腺肿瘤标志物前列腺特异性抗原（PSA）的血清水平可测量值较低。相反，SCC分泌几种神经肽，降钙素（CT）就是其中之一。对16例前列腺SCC患者（5例纯SCC和11例腺癌与SCC合并病例）进行回顾性评估血清CT作为神经内分泌标志物的效用。通过放射免疫测定法测量血清CT。在所有患者中，在组织学诊断SCC后测量血清CT水平。所有16例患者均表现为晚期肿瘤并伴有广泛转移。16例病例中有9例（56%）血清CT升高（范围为42至约2654 pg/ml），从化学角度支持SCC的诊断。由于该研究的回顾性性质，大多数病例中血清CT仅测量一次，无法评估监测疾病进展或化疗反应性的价值。通过对数秩检验进行的生存分析未显示血清CT在前列腺SCC中有统计学意义的预后价值。然而，血清CT水平极高的患者往往生存较差。需要进一步的研究来进一步评估血清CT作为前列腺SCC疾病监测和预后标志物的作用。血清CT可能在前列腺SCC的早期诊断中作为肿瘤标志物发挥作用，前列腺SCC通常直到晚期才被诊断出来。
