An update of the two NSABP studies was recently published by Wapnir et al. The goal of the update was to evaluate long-term invasive ipsilateral in-breast recurrence outcomes in the two studies. The update confirmed previous findings: mortality from DCIS is low regardless of treatment, and recurrence risk is highest in patients who do not receive radiation therapy or tamoxifen.

Standard treatment for DCIS includes breast-conserving surgery, often involving wire or radioactive seed localization; whole-breast radiation therapy; and tamoxifen for localized DCIS. Simple mastectomy and sentinel node biopsy are recommended for extensive or multicentric DCIS and for women in whom adequate cosmesis cannot be achieved because of breast size.

When DCIS accompanies invasive disease, it is called muticentric or multifocal and how to treat such patients is controversial. The consensus remains that mastectomy is standard of care, although more recent retrospective studies suggests that conservative treatment with breast preservation may be adequate (B. Fisher, 2011). There also remains a controversy whether  MRI should be used to identify DCIS and make surgical decisions accordingly.

While a lumpectomy is not inappropriate, it should not be performed without a discussion with the patient and advising her of the need  for radiation and the risk of finding multicentric disease, that would require additional resections or a completion mastectomy.

Cuzick J, Sestak I, Pinder SE, et al. Effect of tamoxifen and radiotherapy in women with locally excised ductal carcinoma in situ: long-term results from the UK/ANZ DCIS trial. Lancet Oncol. 12(1):21-9, 2011.

Wapnir IL, Dignam JJ, Fisher B, et al. Long-term outcomes of invasive ipsilateral breast tumor recurrences after lumpectomy in NSABP B-17 and B-24 randomized clinical trials for DCIS. J Natl Cancer Inst. 103(6):478-88, 2011.

Bernard Fisher  Role of Science in the Treatment of Breast Cancer When Tumor Multicentricity is Present J Natl Cancer Inst. 2011;103(17):1292-1298

Kane RL, Virnig BA, Shamliyan T, Wang SY, Tuttle TM, Wilt TJ. The impact of surgery, radiation, and systemic treatment on outcomes in patients with ductal carcinoma in situ. J Natl Cancer Inst Monogr. 2010(41):130-3, 2010.

Swati Kulkarni Management of DCIS—A Work in Progress ONCOLOGY. Vol. 25 No. 9, 2011

Currently, guidelines indicate MRI for screening of women at high risk based on family history or for clarifying diagnostic dilemmas that are unable to be clarified by mammography and ultrasound. Some physicians adopt the strategy of using MRI to decide between a mastectomy and lumpectomy, when DCIS is present. The reasoning is that if widespread DCIS is found, a mastectomy would be performed rather than a lumpectomy. This strategy has not been formally evaluated and is not recommended by guidelines. A clinical trial is ongoing: Breast MRI as a Preoperative Tool for DCIS, NCT00605982. The purpose of this study is to see how often MRI can find other areas of cancer in women with one area of breast cancer, and to determine how having the MRI test affects their treatment.  The study also aims to follow women who enter the study over a 10-year period to determine how often the breast cancer comes back.

ACR says: ” Invasive carcinoma and ductal cardinoma in situ (DCIS) – Breast MRI may be useful to determine the extent of disease and the presence of multifocality and multicentricity in patients with invasive carcinoma and ductal carcinoma in situ (DCIS). MRI can detect occult disease up to 15% to 30% of the time in the breast containing the index malignancy. MRI determines the extent of disease more accurately than standard mammography and physical examination in many patients. It remains to be conclusively shown that this alters recurrence rates relative to modern surgery, radiation, and systemic therapy.”

REFERENCES:

Kuhl CK, Schrading S, Bieling HB, et al. MRI for diagnosis of pure ductal carcinoma in situ: A prospective observational study. Lancet. 2007;370(9586):485-492.

http://www.acr.org/SecondaryMainMenuCategories/quality_safety/guidelines/breast/MRI_Breast.pdf – 2008

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