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Breast specialists report no clear consensus on management of LCIS (lobular carcinoma in situ), generally considered a pre-cancerous condition that may indicate a patient's future risk of developing invasive breast cancer in either breast. Nearly 120 breast specialists responded to a survey conducted August 2007 on their practices regarding LCIS and pleomorphic LCIS.
Overall, about 70% of all respondents will usually or always recommend an excisional biopsy for LCIS. For patients with LCIS, only a small percentage of respondents would recommend mastectomy, sentinel node biopsy, or axillary lymph node dissection. The percentage of respondents recommending these procedures increases considerably for patients with pleomorphic LCIS, which is generally considered to be more aggressive.
The findings, published in the ASBD Advisor issue 2, 2007, is available online at http://www.asbd.org.
Significance and Treatment of LCIS (excerpts)
http://www.femalepatient.com/html/cme/articles/032_10_053.asp
For many years, ductal and lobular carcinoma in situ of the breast represented a ?gray area? with regard to diagnosis, risk, and treatment. Recently, however, data are emerging that can help women and their surgeons make better informed, evidence-based treatment decisions.
Lobular carcinoma in situ refers to a disorderly proliferation of epithelial cells confined to the terminal ductal-lobular units of breast tissue. It is considered to be the culmination of a spectrum of atypical lobular hyperplasia (ALH) or lobular neoplasia.
First identified in 1942, LCIS has been described as multicentric, bilateral breast change?an indolent lesion of low malignancy that increases a woman?s lifetime risk of breast cancer by 12-fold. There is a 7% incidence of invasive breast cancer within 10 years of diagnosis; subsequent breast cancers can occur as late as 15 years postdiagnosis. No distinctive mammographic characteristics have been identified for LCIS or ALH. In the past, treatment ranged from close observation to bilateral prophylactic mastectomy.
Currently, a diagnosis of LCIS or ALH is most often made on core needle biopsy triggered by a mammographic abnormality, raising questions about the necessity of surgical excision. Reports of the incidence of preinvasive or invasive cancer?all after core needle biopsy findings of lobular neoplasia?range from 2% to 50%, but most studies show a risk of 15% to 20%. For example, 13 breast malignancies (four preinvasive, nine invasive) were identified in 28 patients who underwent excision for lobular neoplasia, with similar findings in five of 21 patients undergoing excision or observation for LCIS or ALH. Ductal carcinoma in situ or invasive cancer was diagnosed in four of 13 LCIS and five of 20 ALH patients who underwent excision; this study included a review of the literature describing 39 breast cancers in 284 patients (16%) with ALH, and 50 breast cancers in 255 patients (19%) with LCIS. Another review of 159 cases of ALH or LCIS noted invasive cancer in 19% of patients. These findings indicate an underestimation of breast disease by core needle biopsy in cases of lobular neoplasia. As LCIS and ALH do not have distinctive mammographic appearances, this undersampling error suggests that these lesions must be excised.
In the past local excision of LCIS was discouraged due to the purported bilateral tendency of the disease, but this may have been overstated. In a study of 252 women diagnosed with ALH, 50 developed invasive cancer?68% in the ipsilateral breast and 24% in the contralateral breast (3:1).
Chemoprophylaxis of invasive cancer is an option for patients with ALH or LCIS. Lobular neoplastic epithelial cells are usually estrogen-receptor-positive. The National Surgical Adjuvant Breast and Bowel Project conducted a prevention trial using tamoxifen, and of the subjects with LCIS, tamoxifen reduced the risk of breast cancer by 56%. Among patients with ALH, 23 in the placebo group developed cancer versus three in the tamoxifen group. Statistically significant adverse effects included an increased incidence of endometrial cancer and pulmonary emboli among women over age 50 years.
A subsequent trial compared tamoxifen with raloxifene for chemoprophylaxis. It found similar breast cancer risk reductions for both drugs, with a trend toward fewer cases of thromboembolism and endometrial cancer in raloxifene users (Figure 4). However, raloxifene was not shown to prevent DCIS or preinvasive breast cancer, whereas tamoxifen did.
Lobular neoplasia, which includes LCIS and ALH, confers an elevated lifetime risk of breast cancer. Due to the risk of sampling error with core needle biopsy, consideration should be given to complete excision. The potential for an underlying malignancy is 20% to 50%. Additionally, the patient should be counseled regarding her lifetime elevated risk of breast cancer, and offered chemoprophylaxis after a careful evaluation of risks and benefits.
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