Euscher Elizabeth, Sui Dawen, Soliman Pamela, Westin Shannon, Ramalingam Preetha, Bassett Roland, Malpica Anais
Departments of Pathology (E.E., P.R., A.M.) Biostatistics (D.S., R.B.) Gynecologic Oncology and Reproductive Medicine (P.S., S.W.), The University of Texas MD Anderson Cancer Center, Houston, Texas.
Int J Gynecol Pathol. 2018 May;37(3):242-251. doi: 10.1097/PGP.0000000000000415.
Sentinel lymph node (SLN) sampling may provide staging information without exposing patients to risks of lymph node dissection. There is no consensus protocol for optimal pathologic handling of these specimens. This study compares 2 ultrastaging protocols of SLN in endometrial carcinoma (EC). All SLN were serially sectioned perpendicular to the long axis in 2 mm intervals and entirely submitted for routine hematoxylin and eosin (H&E) processing. SLN negative by routine processing had ultrastaging (US) by one of the following: method 1 (M1), 5 H&E levels at 250 μm intervals with 2 unstained slides at each level; pankeratin immunohistochemistry (IHC) performed on level 1 in cases with negative H&E levels or method 2 (M2), 1 H&E level + 2 unstained slides cut 250 μm into the tissue block; pankeratin IHC performed in cases with negative H&E. Histologic subtype, numbers of SLN, positive SLN, non-SLN, positive non-SLN, and metastasis size were recorded. A total of 178 patients had 527 SLNs (1-16 per case; median, 2 SLN) sampled during hysterectomy for the following EC histotypes: endometrioid International Federation of Gynecology and Obstetrics grade 1/2, 117 (66%); endometrioid International Federation of Gynecology and Obstetrics grade 3, 18 (10%); serous, 20 (11%); carcinosarcoma, 11 (6%); clear cell, 9 (5%); and undifferentiated, 3 (2%). In all, 172 patients had ultrastaging: M1=65; M2=58. In total, 33 patients were SLN positive. Twenty-seven had SLN submitted for US: M1=11; M2=16. Eleven patients had additional SLN detected by US: M1=5; M2=6. Of these, 8 were patients whose SLN were only detected by US representing an increase of 32% in number of patients with positive SLN. Six patients (M1=2; M2=4) with negative SLN had a positive non-SLN. Mean size of ultrastage-detected metastasis was 0.24 mm for M1 and 0.38 mm for M2. Statistical analysis comparing M1 and M2 detected no statistically significant associations with respect to number of positive SLN detected, size of metastasis or false-negative rate and method. The methods performed similarly for both low-grade and high-grade EC. A more comprehensive US protocol had no significant advantages over a single wide interval and IHC in this study population. A pankeratin IHC stain enhances metastasis detection. Additional studies are required to further test this limited protocol as well as to evaluate the clinical significance of the low volume disease detected by ultrastaging.
前哨淋巴结（SLN）取样可在不使患者面临淋巴结清扫风险的情况下提供分期信息。对于这些标本的最佳病理处理尚无共识方案。本研究比较了子宫内膜癌（EC）中SLN的两种超分期方案。所有SLN均垂直于长轴以2毫米间隔连续切片，并全部送检进行常规苏木精和伊红（H&E）处理。常规处理为阴性的SLN通过以下方法之一进行超分期（US）：方法1（M1），以250微米间隔进行5个H&E水平切片，每个水平有2张未染色切片；在H&E水平为阴性的病例中，在第1水平进行全角蛋白免疫组织化学（IHC）检测；或方法2（M2），1个H&E水平+2张从组织块中切取250微米的未染色切片；在H&E为阴性的病例中进行全角蛋白IHC检测。记录组织学亚型、SLN数量、阳性SLN、非SLN、阳性非SLN和转移灶大小。共有178例患者在子宫切除术中对527个SLN（每例1 - 16个；中位数为2个SLN）进行了取样，用于以下EC组织学类型：国际妇产科联盟1/2级子宫内膜样癌，117例（66%）；国际妇产科联盟3级子宫内膜样癌，18例（10%）；浆液性癌，20例（11%）；癌肉瘤，11例（6%）；透明细胞癌，9例（5%）；未分化癌，3例（2%）。共有172例患者进行了超分期：M1 = 65例；M2 = 58例。总共有33例患者SLN阳性。27例患者的SLN送检进行US检查：M1 = 11例；M2 = 16例。11例患者通过US检测到额外的SLN：M1 = 5例；M2 = 6例。其中，8例患者的SLN仅通过US检测到，这使得SLN阳性患者数量增加了32%。6例（M1 = 2例；M2 = 4例）SLN阴性的患者有阳性非SLN。M1检测到的超分期转移灶平均大小为0.24毫米，M2为0.38毫米。比较M1和M2的统计分析显示，在检测到的阳性SLN数量、转移灶大小或假阴性率以及方法方面，没有统计学上的显著关联。对于低级别和高级别EC，这两种方法表现相似。在本研究人群中，更全面的US方案与单个宽间隔和IHC相比没有显著优势。全角蛋白IHC染色可提高转移灶检测率。需要进一步的研究来进一步测试这个有限的方案，并评估超分期检测到的低容量疾病的临床意义。
