Elshami M.Elamin, MDMedical Oncologist

Central Care Cancer Centerwww.cccancer.comWichita, KS, USA

www.cccancer.com

LCIS

Clusters of ductules or acini filled, distorted and distended by proliferating epithelial cells.

Normal mammogram

Non palpable, incidental finding at biopsy

Multifocal, multicentric, bilateral

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LCIS

Associated with lobular and tubular carcinomas

Decrease after menopause

Risk of invasive cancer is low 21% in 15yrs

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Treatment

Surgery: Excision with close observation Ipsilateral mastectomy without LN

dissection + biopsy of contralateral breast Bilateral mastectomy

Especially if BRCA mutation or strong FH Observation Tamoxifen or Raloxifene No role for RT

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Pleomorphic LCIS

Pleomorphic LCIS is aggressive variant May behave as DCIS Consider complete excision with negative

margins

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DCIS

Presents as palpable mass

Abnormal mammogram 72% = microcalcifications 10% = tissue density, 12% both

Peak incidence: 51 - 59 yrs

> 4.5 cm DCIS has 42% incidence of invasion

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Histologic subtypes of DCIS

High N G Microinvasion

Micropapillary 20% 30% Papillary 7% 7% Comedo (Her2/neu +) 89% 63% Solid, Cripriform 0% 0%

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Multicentricity/Multifocality

Multicentricity: Second separate DCIS at least 5 cm from

primary site 25% in microscopic, 37% in palpable DCIS More common in micropapillary

Multifocality: Within same quadrant or within 5 cm of

primary site

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Diagnosis of DCIS

Multiview mammography + US Characteristic mammographic findings

Diffuse, Linear, extensive pleomorphic calcifications

FNA is not ideal Needle localization biopsy +/- specimen

radiography

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Before starting treatment

Careful pathologic evaluation for: Negative marginsType and sizeMultifocality and microinvasionAll suspicious areas

Consider specimen radiographyPost-Excision mammography

Whenever uncertainty about adequacy of excision

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SLND and DCIS

Complete ALND is not required in the absence of invasive component or proven mets

Consider SLND if: The pt is to be treated with mastectomy

or excision in anatomic location compromising the performance of future SLND

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Lumpectomy

Wide excision + RT 5-20% local failure 50% of recurrences are invasive Patients with low risk could be treated

with lumpectomy alone Wide excision alone for favorable histology

10-22% local failure rate

Schmitt NEJM 1988, Lagios Cancer 1989

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Re-resection to obtain a negative margins

Mastectomy if negative margins are not feasible

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MastectomyMastectomy

Mastectomy +/- SLND +/- Reconstruction Non-palpable DCIS:

Mastectomy without axillary dissection 100% long term survival

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Patients found to have invasive disease at mastectomy or re-excision:

Should be managed as stage I or II LN staging

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DCIS surgical margins

Margins >10 mm Widely accepted as negative May cause less cosmetic outcome

Margins < 1 mm is considered inadequate At chest wall or skin do not mandate re-excision May treat with higher boast dose of RT

Margins 1-10 mm The wider the margins associated with lower

local recurrence

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Risk of recurrence of DCIS

Palpable mass Larger size Higher Grade Close or involved margins Age <50

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DCIS post-surgical treatment

Ipsilateral breast: Tamoxifen X 5yrs

Following L/RT especially if ER +ve Benefit for ER negative is uncertain

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LumpectomyLumpectomy

Excision + RT NSABP-B-17 (Lumpectomy + RT)

5Y EFS: 84.4% vs 75.8% (P 0.001) No change in OS

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DCIS: Recurrence Rate

Noninv % Inv % Excision alone 11 14 Excision + RT 4 5

Surg Oncol Clin North Am 2:75,1993

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NSABP B-24

Tamoxifen followin L/RT: 5% absolute reduction in recurrence risk 37% reduction in relative risk of recurrence

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Update of B17 and B 24

Lumpectomy/RT/Tam: RT reduce invasive recurrence by 59% Tam add 27% reduction RT/Tam reduce invasive recurrence by 70%

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DCIS post-surgical treatment

Contalateral breast: Counseling regarding consideration of

Tamoxifen for risk reduction

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NSABP Breast cancer preventive trial

Tamoxifen reduce invasive cancer by 75% Tamoxefin reduces benign breast disease

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Thanks