Rosen's Breast Pathology, 4e

395

Ductal Carcinoma In Situ

therapy. Ciatto et al. 56 reported that infiltrating carcinoma developed in the ipsilateral breast in 7 of 55 women (12.7%) treated only by local excision or quadrantectomy. The DCIS had been detected through routine examinations or mam- mographic screening in Florence, Italy, from 1968 to 1988. The length of follow-up was not stated. Several population-based prospective analyses of exci- sional surgery alone have been reported. The largest series, from Denmark, consisted of 112 women with a median follow-up of 53 months. 369 Recurrent invasive carcinoma occurred in 5 women (4.4%), and 19 (17%) had recurrent DCIS. The initial lesions ranged from 1 to 80 mm, with a median size of 10 mm. Features favoring recurrence were large nuclear size, lesion size greater than 10 mm, and the presence of comedonecrosis regardless of the histologic sub- type (solid, micropapillary, or cribriform). Papillary lesions, of which there were few, had a high recurrence rate whether or not comedonecrosis was present. Heterogeneity of growth pattern was found in all but 3 of the 112 lesions. Margin sta- tus, evaluable in only about one-third of the cases, did not appear to be a good predictor of recurrence. Recurrences occurred in 33% of cases with negative margins. Review of 132 patients with DCIS diagnosed in Malmo, Sweden, re- vealed that 3 of 21 women (14%) treated by breast-conserv- ing surgery alone developed ipsilateral invasive carcinoma after a median follow-up of 7 years. 370 Two additional studies described the follow-up of women with DCIS detected in regional mammography screening programs and treated by excisional surgery alone. Arnes- son et al. 371 identified 38 women with lesions detected with a single-view mammography technique, who were treated only by “sector resection” with negative margins. After a median follow-up of 60 months, five (13%) patients had recurrent carcinoma consisting of two invasive and three intraductal lesions. The primary lesions associated with recurrence were 3 to 15 mm in size. Cribriform DCIS pre- ceded the two invasive lesions, whereas comedocarcinoma was followed by recurrent DCIS. Carpenter et al. 372 reported on 28 women with lesions detected through screening mammography and clinical examination. Treatment con- sisted of quadrantectomy or segmental resection. No data were given about margin status. After a median follow-up of 38 months, five recurrences detected mammographically as microcalcifications in the region of prior excision con- sisted of one invasive and four intraductal lesions. There was no significant association between the development of recurrent carcinoma and the size of the primary lesions, the size of the excisional biopsy specimen, or the presence of multifocality. Schwartz et al. 373 selected patients with mammographi- cally detected nonpalpable or incidentally discovered DCIS for treatment by excision alone. Patients were eligible for inclusion if the mammographic diameter of the area of cal- cifications did not exceed 25 mm. Comedocarcinoma was present to some extent in 51% of the lesions and was the pre- dominant type in 29%. At least two subtypes of DCIS were present in 41% of the cases. The excisions were not consis- tently studied for margin status. After a median follow-up

recurrence 5 years after biopsy. The other patient was found to have recurrent micropapillary carcinoma 8.8 years after biopsy. In this series, the observed frequency of subsequent carcinoma was 4.3 times (90% CI, 1.1 to 11.1) the expected risk, somewhat higher for nonmicropapillary (5.4) than for micropapillary (3.9) DCIS. Data from a retrospective review of 1,877 biopsies clas- sified as benign in the Nurses’ Health Study were reported in 2007. 147 Previously unrecognized DCIS was identified in 13 specimens (0.7%). Four were classified as low, six as in- termediate, and three as high nuclear grade. Architecturally, seven were cribriform, and three were each solid and micro- papillary. Carcinoma was clinically diagnosed subsequently in the ipsilateral breast in 10 (77%) of the 13 patients after intervals of 2 to 18 years. DCIS was diagnosed in four cases, 2 to 6 years after the initial biopsy that was interpreted as be- nign, and six patients were found to have invasive carcinoma after 4 to 18 years. Three patients who did not have clinically diagnosed subsequent carcinoma had follow-up of 21 to 27 years. When compared with women with nonproliferative fibrocystic changes, the odds ratio for the development of subsequent carcinoma was 20.1 (95% CI, 6.1 to 66.5), and for invasive carcinoma it was 13.5 (95% CI, 3.7 to 49.7). Prior to the emergence of clinical trials, little information was available prospectively about the treatment of DCIS by breast-conserving excision. In 1982, Lagios et al. 267 reported that 3 (15%) of 15 patients treated for DCIS by local exci- sion developed recurrences in the ipsilateral breast during follow-up averaging 44 months. An expanded series consist- ing of 79 patients with average follow-up of 48 months was reported in 1989. 366 Eight patients had developed recurrent carcinoma, four entirely intraductal, and four invasive. Seven of eight recurrences in the breast were in patients with com- edocarcinoma or cribriform carcinoma with comedonecro- sis. The eighth recurrence was associated with “intraductal carcinoma with anaplasia.” Further information about this series was reported in 1994. 367 At that time, the local failure rate in the conserved breast was 14.7% after a mean follow- up of 106 months. Half of the recurrences were described as “minimally invasive carcinomas,” and the others were intraductal. When correlated with histologic features of the initial lesion, the recurrence rate for DCIS of high nuclear grade with comedonecrosis was 30.5%, and for those with intermediate nuclear grade it was 10%. There were no breast recurrences in patients with low-grade DCIS. After follow-up averaging 39 months, Fisher et al. 368 found a breast recurrence rate of 23% in 22 patients with DCIS treated by excisional biopsy alone. These patients had been entered into a clinical trial for invasive carcinoma in which one of the randomized treatments was excision alone, and the diagnosis was corrected to DCIS during a subsequent pathology review. The same report described recurrences in 2 (7%) of the 29 women with retrospectively diagnosed DCIS who had been randomized to receive radiation Breast Conservation by Excision Only—Prospective Data