Management of Ductal Carcinoma In Situ (DCIS) and Lobular Carcinoma In Situ (LCIS)

You may consider answering the following multiple choice questions before reading the information provided.  The answers are given at the bottom of the page.

Q1: A 47 year old woman underwent breast reduction surgery. Pathology revealed evidence of lobular carcinoma in situ. All the following are treatment option except?

1. Observation.
2. Five years of tamoxifen.
3. Bilateral mastectomy.
4. Adjuvant radiation therapy.

Q2: A 53 year old woman underwent screening mammogram examination that showed microcalcification suspicious for malignancy. Core biopsy revealed ductal carcinoma in situ with positive resection margin. All the following are the treatment option except?

1. Wider excision with negative margin and radiation therapy.
2. Mestectomy.
3. Wider excision with negative margin and radiation therapy and chemotherapy.
4. Wider excision with negative margin and radiation therapy and 5 years of tamoxifen.

Q3: Most common presenting manifestation of DCIS is?

1. A palpable mass.
2. Nipple inversion.
3. Skin changes.
4. Microcalcification on mammographic examination.

Q4: All of the following statements are correct except?

1. LCIS is a true precursor lesion for the development of invasive ductal or lobular breast cancer.
2. Mastectomy is a curative therapy for DCIS in over 98% of cases.
3. For DCIS the risk of development of invasive cancer dependent on the histologic grade, lesion size, and the width of the resection margin in women undergoing breast conserving therapy.
4. Lumpectomy and radiation therapy produced long term results identical to the results obtained after a total mastectomy in the management of DCIS.

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Management of Ductal Carcinoma In Situ (DCIS) and Lobular Carcinoma In Situ (LCIS)

Breast carcinomas can be divided into two major groups:

·  In situ carcinoma: The tumor cells remain confined to the ducts or lobules and there is no invasion into the surrounding stroma.
·  Invasive carcinoma: The tumor cells invade the breast stroma and have the potential to metastasize.

The in situ carcinomas of the breast are either ductal carcinoma in situ (also known as intraductal carcinoma) or lobular carcinoma in situ.

Ductal Carcinoma In Situ (DCIS)
·  DCIS is considered to be a direct precursor of invasive breast cancer. It is also a marker of an increased risk of development of invasive cancer in the ipsilateral or contralateral breast.
·  The risk of development of invasive cancer varies and dependent on the histologic grade, lesion size, and age; and the width of the resection margin in women undergoing breast conserving therapy.


Clinical Features
·  Ninety percent of women with mammographically detected DCIS have occult microcalcification on mammographic examination.
·  Less common findings include a mass, prominent ducts, or other soft tissue changes.

Classification
·  DCIS has been conventionally classified according to architectural pattern (ie, comedo, cribriform, micropapillary, papillary and solid types).
·  The newer classification systems for DCIS are based on histologic factors that correlate with risk of local recurrence.
·  The University of Southern California/Van Nuys Prognostic Index (USC/VNPI) incorporates lesion size, age, histologic features, and surgical margin width as a measure of predicting outcome in patients with DCIS.

Management

Mastectomy

·  Mastectomy is curative in over 98% of cases. It is a treatment of choice in extensive disease that cannot be encompassed within a cosmetically acceptable resection.

Breast Conservation Therapy (BCT)

·  No randomized trial has compared mastectomy to BCT for the treatment of DCIS. Nevertheless, the results of several randomized trials have shown that lumpectomy and radiation therapy produced long term results identical to the results obtained after a total mastectomy.
·  Axillary lymph node dissection is not indicated but for larger noninvasive tumor (>5cm) or higher-risk DCIS some experts recommend sentinel lymph node examination due to risk of underlying microinvasive cancer.

Tamoxifen

·  The available trials are conflicting as to the benefit of tamoxifen in DCIS.
·  The NSABP B-24 trial showed that adding 5 years of tamoxifen to BCT (lumpectomy and radiation therapy) was associated with 44% relative reduction in risk of ipsilateral invasive cancer1. Subsequent report suggested that the benefit of tamoxifen in DCIS was confined to the estrogen receptor positive subset.
·  Tamoxifen can be considered for women with high risk DCIS for additional local prophylaxis.

Lobular Carcinoma In Situ (LCIS)
·  LCIS has been associated with a substantially increased risk of development of invasive breast cancer. In contrast to DCIS, LCIS is considered to be a risk factor, rather than a true precursor lesion for the development of invasive ductal or lobular breast cancer.
·  The absolute risk is approximately 1% per year, and appears to be life-long. The risk to each breast is approximately equal and approaches 15% within ten to fifteen years.

Clinical Features
·  LCIS is not a palpable lesion.
·  LCIS does not have a characteristic mammographic appearance.
·  LCIS usually is an incidental finding in breast tissue removed for another reason.

Management

Treatment options for LCIS include careful surveillance, chemoprevention with a selective estrogen receptor modulator (SERM), or bilateral prophylactic mastectomy.

Re-excision

·  Wide surgical excision with histologically negative margins is not needed since LCIS is often multicentric. Nevertheless in about 15-38% cases diagnosis may be upgraded to DCIS or invasive cancer and most experts recommend a wire-localized excisional biopsy if LCIS was diagnosed by a core needle biopsy to exclude underlying DCIS or invasive cancer.

Surveillance

·  Careful observation with history and physical examination every 6 to 12 months, and annual screening mammography is preferred option for many women with LCIS to avoid treatment related adverse effects.

Selective Estrogen Receptor Modulators (SERMS)

·  Five years of a SERMS such as tamoxifen (20 mg daily) or raloxifene (60 mg daily) is an acceptable alternative for women with LCIS.
·  In the NSABP P1 trial, in women with LCIS, 5 years of tamoxifen was associated with 56% relative reduction in the risk of development of invasive breast cancer2. Tamoxifen however has been associated with 2.4 relative risk of development of uterine cancer and 1.9 relative risk of experiencing a thromboembolic event.
·  The NSABP P2 (STAR) trial suggests that raloxifene has similar efficacy as tamoxifen in reducing the incidence of invasive breast cancers in high-risk women with a significantly lower risk of thromboembolism and uterine cancer3. However, raloxifene is not as effective as tamoxifen against noninvasive breast cancers.

Prophylactic Bilateral Mastectomy

·  Despite high risk for developing invasive breast cancer compared with general population, most women will not develop invasive cancer within their lifetime. Therefore, the decision to pursue prophylactic surgery must be highly individualized.

Key Points
·  DCIS and LCIS are non-invasive cancers that predict the subsequent risk of development of invasive cancer.
·  Unlike LCIS, DCIS is a true precursor lesion for the development of invasive cancer.
·  Treatment options for DCIS include mastectomy or breast conservative the rapt (Lumpectomy and radiation) with or without 5 years of tamoxifen.
·  Treatment options for LCIS include observation, chemoprevention with 5 years of tamoxifen or raloxifene, or bilateral mastectomy.

References

1. Fisher B; Dignam J; Wolmark N; Tamoxifen in treatment of intraductal breast cancer: National Surgical Adjuvant Breast and Bowel Project B-24 randomised controlled trial. Lancet 1999 Jun 12;353(9169):1993-2000.

2. Fisher B, Costantino JP, Wickerham DL, et al. Tamoxifen for the prevention of breast cancer: current status of the National Surgical Adjuvant Breast and Bowel Project P-1 study. J Natl Cancer Inst 2005 Nov 16;97(22):1652-62.

3. Vogel VG, Costantino JP, Wickerham DL,Effects of tamoxifen vs raloxifene on the risk of developing invasive breast cancer and other disease outcomes: the NSABP Study of Tamoxifen and Raloxifene (STAR) P-2 trial. JAMA 2006 Jun 21;295(23):2727-41.

 

Multiple choice question answers:

Q1:     Answer: 4

Q2:     Answer: 3

Q3:     Answer: 4

Q4:     Answer: 1