Approach

Ductal carcinoma in situ (DCIS) in women is typically asymptomatic and diagnosed during routine screening mammography. Less commonly, women with DCIS may present with a breast lump, nipple discharge, or Paget disease of the breast. Lobular carcinoma in situ (LCIS) is usually discovered incidentally, often in conjunction with other clinically identified malignant or benign lesions such as fibroadenoma, cysts, papilloma, papillomatosis, fat necrosis, or breast abscesses.

There are no classic mammographic findings for LCIS, whereas DCIS often presents with clustered microcalcifications.[2]​​

Clinical assessment

DCIS and LCIS are typically asymptomatic.

Rarely, DCIS may present as an eczematous-like rash on the nipple if presenting as Paget disease. In the absence of medical attention, a woman may present with ulceration. Other uncommon presenting symptoms of DCIS include nipple discharge or a breast lump.

The first symptom in males diagnosed with DCIS is generally bloody nipple discharge.[50]

Imaging

National Comprehensive Cancer Network (NCCN) guidelines recommend digital breast tomosynthesis (three-dimensional mammography) alongside conventional two-dimensional mammography for screening and diagnosis, which may reduce the need for additional imaging.[51]​​

A mammographic finding in one breast of clustered microcalcifications and absence of a soft-tissue abnormality indicates DCIS. Calcifications may be linear, branching, or bizarre in comedo DCIS. Noncomedo DCIS may not be calcified or may present as fine granular powdery calcifications.

LCIS does not have classic mammographic findings.

If microcalcifications are not detected by mammography, then compression mammography, mammographic magnification views, ultrasonography, and/or magnetic resonance imaging (MRI) may be considered. For nonspecific lesions, magnification views, with or without ultrasound, are generally performed. To differentiate cystic from solid lesions, ultrasound is performed.

Mammographic sensitivity is lower in women with dense breasts, therefore supplemental imaging (e.g., ultrasound, MRI) may be warranted in these women.[51][52][53]​​[54]

MRI may be especially helpful in detecting high-grade DCIS.[44]​​​[55][56]​​​​​​​​​​​​​​​​​​​ Although MRI can accurately detect additional lesions and contralateral cancer not identified using conventional imaging in primary breast cancer, MRI findings should be pathologically verified because of the high false-positive rate.[57][58]​​​ Do not routinely order MRI in patients with a new diagnosis of breast cancer.[59][60]​​ Although breast MRI can be useful in select patients to aid treatment decisions, there is a lack of evidence that routine use of MRI in new breast cancer patients lessens cancer recurrence, death from cancer or the need for reoperation after lumpectomy surgery.​[59]​ Breast MRI should not be used routinely for the preoperative workup of patients with DCIS.[61][62][63]

Do not perform positron emission tomography, computed tomography, or radionuclide bone scans in the staging of early breast cancer at low risk for metastasis; there is no evidence of benefit in asymptomatic individuals with newly identified DCIS.​[60][64]​​

Biopsy

Core needle or excisional biopsy techniques are used when breast cancer is suspected. The choice depends on the purpose of the procedure.

Core needle biopsy

Often a good option. However, results are only diagnostic and not definitive, and may underestimate the extent of disease.[65] Architecturally, papillomas can cause false-positives. Furthermore, many breast malignancies contain elements of both in situ and invasive carcinoma. As such, a core biopsy demonstrating one component does not exclude the other. Stereotactic (mammographically guided) core needle biopsy is the diagnostic procedure of choice in the setting of microcalcifications, as it is nearly as accurate as excisional biopsy, with fewer complications.[66] Ultrasound-guided core biopsy is preferred if a nonpalpable mass is found on imaging.

Excisional biopsy

Provides a complete diagnosis and the opportunity for treatment. However, it is associated with poorer cosmesis than needle biopsies, is more costly, and requires surgery.

Excisional biopsy is recommended:[51]

  • If core needle biopsy cannot be performed

  • When core needle biopsy results are indeterminate, or benign and discordant with imaging

  • For nonclassic LCIS (pleomorphic or florid)

  • For select patients with classic LCIS (if core needle biopsy results discordant with imaging or based on level of suspicion)

Pathologic analysis of biopsy

Necessary for scoring by nuclear grade and architecture.

Ductal lavage or nipple aspirate fluid collection analysis may prove to be useful for diagnosis.[67] However, concomitant use of detection markers may be required to improve sensitivity (e.g., basic fibroblast growth factor). More evidence is needed.

Sentinel lymph node biopsy

Sentinel lymph node biopsy (SLNB) should be strongly considered if the patient is undergoing mastectomy, or if tumor excision occurs in an anatomic location making it difficult to perform a future SLNB.[68] Performing an SLNB after mastectomy is impractical. Guidelines do not recommend SLNB in women with DCIS who are undergoing breast-conserving surgery.[68][69]

Hormone receptor testing

Estrogen and progesterone receptor status is measured by immunohistochemical staining of fixed tumor tissue. Results can help guide treatment.[70]

Genetic evaluation

Genetic counseling and germline testing for high-penetrance breast cancer susceptibility genes (e.g., BRCA1, BRCA2, CDH1, PALB2, PTEN, STK11, and TP53) should be considered for women at high risk for hereditary breast cancer (e.g., based on personal and/or family history).[49][71][72][73][74]

Genetic testing for a specific pathogenic variant can be carried out, if known; germline multigene panel testing is recommended if the variant is unknown.[49][75] Selection of the specific multigene panel should take into account the patient's personal and family history. Results can inform prognosis and may highlight risk among family members.​

If there are existing genetic test results, do not order a duplicate test unless there is uncertainty about the existing result, for example the result is inconsistent with the patient’s clinical presentation or the test methodology has changed.[76]

See Primary invasive breast cancer (Screening) topic for specific criteria for genetic counseling and testing.

Use of this content is subject to our disclaimer