33 Special Types of Invasive Breast Carcinoma: Diagnostic Criteria ...

LCIS vs DCIS
• Patients with lobular ca have � risk for bilateral disease
(~1/3 rd of cases [9-69%]).
• Yet, pts with ductal carcinoma ALSO have ↑ risk of
bilateral disease (~1/6 th of cases [1-25%]).
• A related issue - ipsilateral multicentricity:
R t d i 2/3 rds Reported in ~2/3 f LCIS [42 86%]
rds for LCIS [42-86%].
Reported in ~1/3 rd for DCIS [23-46%].
• DCIS currently considered amenable to local-regional
therapies - LCIS is not, because of the latter’s greater
risk of multicentricity & bilaterality.
• Ottesen reported follow-up study of 69 patients with
pure LCIS and 19 patients with LCIS + DCIS treated
with excision only (AJSP 17:14-21,1993).
• Some (i.e., LCIS + DCIS cells) were found close and
merging, with individual CIS cells indistinguishable in
junctional zone.
• Thus, “LCIS occurring with DCIS (22%) makes a
theory of coincidence unlikely, but rather indicates a
relation between the two.”
•Of LCIS cases, 20% had both small (type A) and large
(type B) nuclei (i.e., large or type B cells are DCIS-like).
10/8/2011
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