Radiation Oncology/Breast/LCIS

Risk of invasive cancer SEER data, 2005 (1973-98) - 16110014 — "Bilateral risk for subsequent breast cancer after lobular carcinoma-in-situ: analysis of surveillance, epidemiology, and end results data." Chuba PJ et al. J Clin Oncol. 2005 Aug 20;23(24):5534-41. Incidence of invasive carcinoma 7.1% at 10 yrs, 18% at 25 yrs. 46% ipsilateral / 54% contralateral. Higher proportion of cancers with ILC than in the general population (23.1% vs 6.5%). Conclusion: LCIS is associated with increased risk of subsequent invasive breast cancer, which can occur with roughly equal probability in either breast. Prevention of invasive cancer P-1 prevention trial See page at Prevention for detail. 43% risk reduction with tamoxifen overall (46% for those with LCIS). Surgery alone NSABP - 14716756 — "Pathologic findings from the National Surgical Adjuvant Breast and Bowel Project: twelve-year observations concerning lobular carcinoma in situ." Fisher ER et al. Cancer. 2004 Jan 15;100(2):238-44. Analysis of previous NSABP trial. 12-year results of 180 pts treated with surgical excision only. IBTR in 14.4% and CBTR in 7.8%. 9 of 26 IBTR and 10 of 14 CBTR were invasive, mostly invasive lobular carcinoma. Conclusion: LCIS is an indolent disease and can be managed with conservative surgery LCIS concurrent with breast carcinoma U. Michigan; 2006 (1989-2003) 16329136 -- "Is lobular carcinoma in situ as a component of breast carcinoma a risk factor for local failure after breast-conserving therapy? Results of a matched pair analysis." (Ben-David MA, Cancer. 2006 Jan 1;106(1):28-34.) Retrospective. 64 pts with Stage 0-II (DCIS or invasive ca.) breast carcinoma with LCIS as a component of the primary tumor. Compared with matched controls (LCIS-). Conclusion: The extent of LCIS and its presence at the margins did not reduce the excellent rates of local control after BCS+RT. The data suggest that LCIS in the tumor specimen, even when multifocal, should not affect selection of patients for BCS and whole-breast RT. Pleomorphic LCIS Uncommon (12% of LCIS cases). May be associated with invasive carcinoma (usually invasive lobular) 25% of the time. Biologically can behave similar to high grade DCIS. Treatment is controversial. Some recommend complete excision with negative margins (see NCCN Guidelines 2011-1). 2013: Review 23357705 Full text -- "Challenges in the management of pleomorphic lobular carcinoma in situ of the breast." (Masannat YA, Breast. 2013 Apr;22(2):194-6.) 2012: Case report - 22037287 Full text -- "Pleomorphic lobular carcinoma in situ: treatment options for a new pathologic entity." (Murray L, Clin Breast Cancer. 2012 Feb;12(1):76-9.) 2011: MDACC - 21631266 -- "Clinical implications of margin involvement by pleomorphic lobular carcinoma in situ." (Downs-Kelly E, Arch Pathol Lab Med. 2011 Jun;135(6):737-43.) Conclusion: "This is the first series, to our knowledge, that evaluates margin status in patients with PLCIS and documents recurrence. Recurrent PLCIS was identified at a rate similar to low- or intermediate-grade ductal carcinoma in situ. Therefore, known methods of local control, including surgical excision with negative margins (2 mm), may be the appropriate treatment in these patients." Reviews 2011 (MSKCC) Full text -- "Recommendations for Women With Lobular Carcinoma In Situ (LCIS)" (Oppong BA, Oncology. 2011 Oct 12;25(11)