Lagios M D, Silverstein M J
Breast Cancer Consultation Service, St. Mary's Medical Center, San Francisco, USA.
Surg Oncol Clin N Am. 1997 Apr;6(2):385-92.
A combined database of 342 patients with DCIS treated by lumpectomy alone versus lumpectomy and radiation therapy with a median 82-month follow-up is summarized in this joint study. Reproducible subtype classification and common methods of mammographic-pathologic correlation and complete tissue processing are unique features of this database, and they permit outcome to be analyzed by pathologic subtype, size, and margine status. Striking differences are noted in local control rates analyzed by subtype, which were largely independent of irradiation (see Table 1). Analysis of local recurrence-free survival restricted to those cases with a 10 mm or larger free margin width revealed no significant differences between the irradiated and nonirradiated groups. The local recurrence rates were 5% in those treated by lumpectomy alone and 4.5% in those treated by lumpectomy and irradiation (Table 4). Although differences in local recurrence rates for DCIS with a 10 mm plus free margin, with or without irradiation, were noted, they were not large. For DCIS patients with adequate (10 mm or more) or intermediate (1-9 mm) margin width, there was a reduction in local recurrence limited to the high-grade subtype (group III) with radiation therapy; an absolute 8% reduction for those with adequate margins and 11% for those with intermediate margins, but the difference was significant only for the latter group (Table 5). However, no significant differences were noted for the lower grade DCIS subtypes (groups I and II). For DCIS patients with inadequate margins (i.e., less than 1 mm), irradiation provided no benefit for local control. We conclude that an adequate surgical excision for DCIS, defined as a free margin of 10 mm or more, largely makes moot the question of local control related to pathologic subtype and treatment modality. Specifically, adequately excised high-grade (group III) DCIS received a benefit for local control from radiation therapy of only 8% within the median follow-up period. This difference is not significant. The impact of DCIS size or extent on local recurrence is much smaller than margin width (see Table 3). Significant differences achieved by radiation therapy were demonstrable only for the smallest size group (15 mm or less) in the highgrade subtype (group III). Differences in local recurrence rates for low and intermediate subtypes (group I and II) based on radiation therapy could not be demonstrated within the three size categories used in the study. We conclude that although adequate margins are more difficult to achieve for larger or more extensive DCIS, size alone is not a prohibition to breast conservation.
这项联合研究总结了一个包含342例仅接受肿块切除术与接受肿块切除术加放射治疗的导管原位癌（DCIS）患者的综合数据库，中位随访时间为82个月。可重复的亚型分类、乳腺X线摄影-病理相关性的常用方法以及完整的组织处理是该数据库的独特特征，它们使得能够按病理亚型、大小和切缘状态分析结果。按亚型分析的局部控制率存在显著差异，这些差异在很大程度上与放疗无关（见表1）。对切缘宽度为10毫米或更大的病例的局部无复发生存率分析显示，放疗组与未放疗组之间无显著差异。仅接受肿块切除术的患者局部复发率为5%，接受肿块切除术加放疗的患者局部复发率为4.5%（表4）。虽然注意到切缘宽度为10毫米及以上的DCIS无论是否接受放疗，其局部复发率存在差异，但差异不大。对于切缘宽度足够（10毫米或更多）或中等（1 - 9毫米）的DCIS患者，放疗仅使高级别亚型（III组）的局部复发有所减少；切缘足够的患者绝对降低了8%，切缘中等的患者绝对降低了11%，但仅后一组差异有统计学意义（表5）。然而，低级别DCIS亚型（I组和II组）未观察到显著差异。对于切缘不足（即小于1毫米）的DCIS患者，放疗对局部控制无益处。我们得出结论，对于DCIS，定义为切缘宽度10毫米或更多的充分手术切除在很大程度上使与病理亚型和治疗方式相关的局部控制问题变得没有实际意义。具体而言，在中位随访期内，充分切除的高级别（III组）DCIS从放疗中获得的局部控制益处仅为8%。这种差异无统计学意义。DCIS大小或范围对局部复发的影响远小于切缘宽度（见表3）。放疗仅在高级别亚型（III组）中最小尺寸组（15毫米或更小）显示出显著差异。在该研究使用的三个大小类别中，未显示低级别和中级别亚型（I组和II组）基于放疗的局部复发率差异。我们得出结论，虽然对于更大或范围更广的DCIS更难获得足够的切缘，但仅大小本身并非保乳的禁忌证。
