Primary signet ring cell carcinoma (PSRCC) of the prostate is an extremely rare variant of prostatic adenocarcinoma. A PubMed search of the English language literature from January 2000 to June 2020 using the keywords “signet ring cell carcinoma” and “prostate,” identified 20 cases of PSRCC of the prostate. On the basis of the combined data from this study and the literature review, 21 such patients were evaluated for clinical characteristics, histologic diagnoses, special and immunohistochemical staining, and treatment. The mean age at the diagnosis was 68.47 years (range 50–85 years). The prostate-specific antigen (PSA) levels varied from 0.19 to 6658 ng/mL, with a mean of 509.15 ng/mL. Most (50%) presented with Stage 3 cancer. The most common Gleason grade group was 5 (Gleason score 9 to 10), seen in 61.5%. The extent of signet ring cell involvement of the specimen when reported was documented as more than 20% of the tumor-containing signet ring cells, with a range of 25%–90%. For pathologic diagnosis, the most common special stains performed were periodic acid–Schiff and Alcian blue, and among the immunohistochemical stains, the most common were PSA, CK20, and prostate-specific acid phosphatase. A detailed clinicoradiological and pathological workup is essential to rule out primary from other common sites, in view of its grave prognosis and lack of an established treatment protocol.

前列腺原发性印戒细胞癌（PSRCC）是前列腺腺癌的一种极其罕见的变体。PubMed 使用关键词“印戒细胞癌”和“前列腺”对 2000 年 1 月至 2020 年 6 月的英文文献进行了检索，发现了 20 例前列腺 PSRCC。根据本研究和文献综述的综合数据，对 21 名此类患者的临床特征、组织学诊断、特殊和免疫组织化学染色以及治疗进行了评估。诊断时的平均年龄为 68.47 岁（范围 50-85 岁）。前列腺特异性抗原 (PSA) 水平范围为 0.19 至 6658 ng/mL，平均值为 509.15 ng/mL。大多数 (50%) 患有 3 期癌症。最常见的格里森等级组为 5 级（格里森评分为 9 至 10），占 61.5%。报告时，标本中印戒细胞受累的程度被记录为超过 20% 的含肿瘤印戒细胞，范围为 25%–90%。对于病理诊断，最常见的特殊染色是高碘酸希夫和阿尔新蓝，免疫组化染色中最常见的是PSA、CK20和前列腺特异性酸性磷酸酶。鉴于其严重的预后和缺乏既定的治疗方案，详细的临床放射学和病理学检查对于排除其他常见部位的原发性病变至关重要。