Molina Burgos R, Millán Salvador J M, Oltra Soler J S, Jiménez Cruz J F
Servicio de Urología, Hospital Universitario La Fe, Valencia.
Actas Urol Esp. 2003 Sep;27(8):618-28. doi: 10.1016/s0210-4806(03)72984-2.
Taking into account the precocity of the genetic alterations in the carcinogenesis of the bladder tumors, the valuation of these changes at a level of 9p 21-22 by means of microsatellite markers could be useful for the diagnostic and follow-up.
To evaluate the use of microsatellite markers and the utility of loss of heterozigosity (LOH) and microsatellite instability (MSI) in exfoliated cells from urine sediment. This observation offers the possibility of tumor detection by examining the DNA of urinary sediment.
We amplified with PCR the DNA of urine and blood samples from 160 patients with bladder cancer. We analysed LOH/MSI in cells from urinary sediment using four microsatellite markers of 9p 21-22 (D9S747-D9S171-D9S162-IFNA) and one from chromosome 4 (D4S243). The urinary cytology was used as comparative method and histological examination of tissue obtained by transurethral resection (TUR) as reference diagnostic. We calculated the sensitivity and specificity of this method and if there was some correlation between stage and grade tumoral.
We could use 150 samples correctly. In 111 samples we found LOH/MSI (sensitivity 74%). The cytology was positive only in 60 patients (sensitivity 40%). We found a bigger number of microsatellite alterations (AM) in superficial tumors (sensibility 77.3% vs. 28.8% for the cytology) and these were significant when comparing tumors GI-II vs. GIII (MSI p < 0.001--LOH p < 0.004). The marker with more sensibility was D4S243 with 40%. One patient with prostate carcinoma and another one with chronic cystitis gave false positive results.
The study of LOH/MSI in bladder tumors with 5 microsatellites markers, according to our results showed a sensibility of 74%. The biggest number in LOH/MSI was found in superficial tumors and GI-GII tumors. Although we cannot discard the cystoscopy study in the diagnostic and follow-up, the sensitivity of the urine cytology is better and could be one alternative diagnostic as a non-invasive procedure.
考虑到膀胱肿瘤致癌过程中基因改变的早熟性，通过微卫星标记在9p 21 - 22水平评估这些变化可能对诊断和随访有用。
评估微卫星标记的使用以及尿液沉淀物中脱落细胞的杂合性缺失（LOH）和微卫星不稳定性（MSI）的效用。该观察结果提供了通过检测尿液沉淀物DNA进行肿瘤检测的可能性。
我们用PCR扩增了160例膀胱癌患者尿液和血液样本的DNA。我们使用9p 21 - 22的四个微卫星标记（D9S747 - D9S171 - D9S162 - IFNA）和来自4号染色体的一个标记（D4S243）分析尿液沉淀物细胞中的LOH/MSI。尿液细胞学用作比较方法，经尿道切除术（TUR）获得的组织的组织学检查用作参考诊断。我们计算了该方法的敏感性和特异性，以及肿瘤分期和分级之间是否存在某种相关性。
我们可以正确使用150个样本。在111个样本中我们发现了LOH/MSI（敏感性74%）。细胞学仅在60例患者中呈阳性（敏感性40%）。我们在浅表肿瘤中发现了更多的微卫星改变（AM）（敏感性77.3%，而细胞学为28.8%），并且在比较G1 - II期肿瘤与GIII期肿瘤时这些差异具有统计学意义（MSI p < 0.001 - LOH p < 0.004）。敏感性最高的标记是D4S243，为40%。一名前列腺癌患者和另一名慢性膀胱炎患者给出了假阳性结果。
根据我们的结果，用5个微卫星标记研究膀胱肿瘤中的LOH/MSI显示敏感性为74%。在浅表肿瘤以及G1 - GII期肿瘤中发现的LOH/MSI数量最多。虽然我们不能在诊断和随访中放弃膀胱镜检查，但尿液细胞学的敏感性更高，并且作为一种非侵入性程序可以作为一种替代诊断方法。
