NCCN VERSION 2 2015

NCCN Guidelines Version 2.2015 Breast Cancer

NCCN Guidelines Index Breast Cancer Table of Contents Discussion

patients with pleomorphic LCIS are lacking, due in part to a paucity of histologic categorization of variants of LCIS. Therefore, recommendations on the treatment of pleomorphic LCIS as a distinct entity of LCIS have not been made by the panel. Patients with a confirmed diagnosis of LCIS should be counseled regarding reducing the risk of developing invasive cancer (see NCCN Guidelines for Breast Cancer Risk Reduction ). Surveillance Follow-up of patients with LCIS includes interval history and physical examinations every 6 to 12 months. Annual diagnostic mammography is recommended in patients being followed with clinical observation; see also the NCCN Guidelines for Breast Cancer Screening and Diagnosis . Patients receiving a risk reduction agent should be monitored as described in the NCCN Guidelines for Breast Cancer Risk Reduction . The recommended workup and staging of DCIS includes: history and physical examination; bilateral diagnostic mammography; pathology review; and tumor ER determination. Genetic counseling is recommended if the patient is considered to be at high risk for hereditary breast cancer as defined by the NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast and Ovarian . Although HER2 status is of prognostic significance in invasive cancer, its importance in DCIS has not been elucidated. To date studies have either found unclear or weak evidence of HER2 status as a prognostic indicator in DCIS. 40-43 The NCCN Panel concluded that knowing the Ductal Carcinoma in Situ (Stage 0, Tis, N0, M0) Workup

Workup Recommended workup includes history and physical examination, diagnostic bilateral mammography, and pathology review. Primary Treatment Controversy exists regarding whether an open surgical excision should be performed of the region of LCIS diagnosed by core biopsy and that is not associated with a mammographic structural abnormality or residual mammographic calcifications. Small retrospective studies have concluded that excision following the diagnosis of LCIS on core needle biopsy is not necessary. 30-32 Other studies have shown that 17% to 27% of patients with LCIS diagnosed by core needle biopsy are upgraded to having invasive cancer or DCIS after larger excisional biopsy. 33-37 Based on core needle biopsies, it may be possible to identify subsets of patients with LCIS who can be safely spared a surgical excision. 32 There are some data of small groups of patients suggesting that LCIS subtypes, including pleomorphic LCIS and LCIS associated with necrosis, carry a risk for associated invasive carcinoma similar to DCIS. Therefore, according to the NCCN Panel, it is reasonable to perform surgical excision of LCIS found in a core biopsy to exclude an associated invasive cancer or DCIS. More than 4 foci of LCIS may also increase the risk for upstaging on surgical biopsy. 38 The NCCN Panel recommends that LCIS of the usual type (involving <4 terminal ductal lobular units in a single core) found on core biopsy, as a result of routine screening for calcifications and without imaging discordance, may be managed by imaging follow-up. There is evidence to support the existence of histologically aggressive variants of LCIS (eg, “pleomorphic” LCIS), which may have a greater potential than classic LCIS to develop into invasive lobular carcinoma. 39 Clinicians may consider complete excision with negative margins for pleomorphic LCIS. However, outcome data regarding treatment of

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