Guidi A J, Connolly J L, Harris J R, Schnitt S J
Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA.
Cancer. 1997 Apr 15;79(8):1568-73.
The presence of tumor at the inked margins (IMs) of breast specimens is associated with an increased risk of local recurrence after breast-conserving therapy for invasive breast carcinoma and ductal carcinoma in situ (DCIS). Given the importance of margin status, some have advocated the use of shaved margins (SMs) as a means of conducting a more complete examination of the specimen margins than could be done with sections taken perpendicular to the IMs. However, it is not known whether these two methods of margin assessment provide comparable information.
To address this issue, the authors studied 22 consecutive breast reexcision specimens (10 DCIS, 6 infiltrating ductal carcinomas, and 6 infiltrating lobular carcinomas) in which the specimen surfaces were inked, the margins were shaved, and tumor was present in at least one of the SM sections. A total of 199 SMs were examined. The SMs were originally embedded in a way that permitted histologic sections to be cut opposite the inked surface. Sections of SM stained with hematoxylin and eosin (H & E) were reviewed and scored for the presence and extent (number of low-power fields) of cancer. The remaining tissue from the SM was then removed from the blocks, cut perpendicular to the IM, and reembedded to permit visualization of tumor in relation to the IM. Sections were then cut from two different levels of each reembedded block and stained with H & E. An SM was considered positive if tumor was present anywhere on the section. An IM was considered positive when tumor extended to the inked surface.
Although all 22 excisions had at least 1 positive SM, tumor was present at an IM in only 12 specimens (55%). Among 69 positive SMs, the corresponding IM was positive in only 42 (61%). The likelihood of a positive IM increased with the number of low-power fields of involvement by invasive carcinoma or DCIS on the SM, as follows: 19% with 1 low power-field, 67% with 2 low-power fields, and 97% with > or = 3 low-power fields (all P < 0.02). When the SM was negative, the corresponding IM was negative in 98% of cases.
Many patients with positive SMs do not have positive IMs. A positive SM more reliably predicts a positive IM when tumor involves > or = 3 low-power fields of the SM. The authors conclude that the clinical implications of a positive SM may not be the same as those of a positive IM. Clinical outcome studies are needed to define further the implications of positive SMs. [See editorial counterpoint on pages 1453-8 and reply to counterpoint on pages 1459-60, this issue.]
乳腺标本的墨染切缘（IMs）处存在肿瘤与浸润性乳腺癌和原位导管癌（DCIS）保乳治疗后局部复发风险增加相关。鉴于切缘状态的重要性，一些人主张使用剃除切缘（SMs）作为一种比垂直于IMs取材切片能更全面检查标本切缘的方法。然而，尚不清楚这两种切缘评估方法所提供的信息是否具有可比性。
为解决这一问题，作者研究了连续22例乳腺再次切除标本（10例DCIS、6例浸润性导管癌和6例浸润性小叶癌），这些标本表面进行了墨染，切缘进行了剃除，且在至少一张SM切片中发现肿瘤。共检查了199个SMs。SMs最初的包埋方式允许在与墨染面相对的位置切取组织学切片。对苏木精和伊红（H&E）染色的SM切片进行复查，并对癌症的存在情况和范围（低倍视野数量）进行评分。然后将SM剩余的组织从蜡块中取出，垂直于IM进行切割，重新包埋以观察肿瘤与IM的关系。接着从每个重新包埋蜡块的两个不同层面切片，并用H&E染色。如果切片上任何位置存在肿瘤，则该SM被视为阳性。当肿瘤延伸至墨染面时，IM被视为阳性。
尽管所有22例切除标本中至少有1个阳性SM，但仅12例标本（55%）的IM处存在肿瘤。在69个阳性SMs中，相应的IM仅42个为阳性（61%）。IM为阳性的可能性随着SM上浸润性癌或DCIS累及的低倍视野数量增加而增加，如下：1个低倍视野时为19%，2个低倍视野时为67%，≥3个低倍视野时为97%（所有P<0.02）。当SM为阴性时，98%的病例中相应的IM为阴性。
许多SMs阳性的患者IMs并非阳性。当肿瘤累及SM的≥3个低倍视野时，阳性SM更可靠地预测阳性IM。作者得出结论，阳性SM的临床意义可能与阳性IM不同。需要进行临床结局研究以进一步明确阳性SMs的意义。[见本期第1453 - 1458页的编辑观点及第1459 - 1460页对观点的回应。]
